TWI909306B - Non-oriented electrical steel sheet - Google Patents

Abstract

The non-directional electromagnetic steel plate of this case has a specified chemical composition, and when the surface parallel to the steel plate is observed using EBSD, the total area S _tot , the area of the {411} oriented grains S ₄₁₁ , the area of the {100} oriented grains S ₁₀₀ , the area of the oriented grains with a Taylor factor M exceeding 2.9 according to formula (2) S _tyl , the total area of the oriented grains with a Taylor factor M less than 2.9 S _tra , the average KAM value K ₄₁₁ of the {411} oriented grains, and the average KAM value K _tyl of the oriented grains with a Taylor factor M exceeding 2.9 satisfy formulas (3) to (7). M＝(cosϕ×cosλ) ^-1 (2) S ₄₁₁ /S ₁₀₀ ＞1.00 (3) 0.20≦S _tyl /S _tot ≦0.85 (4) 0.05≦S ₄₁₁ /S _tot ≦0.80 (5) S ₄₁₁ /S _tra ≧0.50 (6) K ₄₁₁ /K _tyl ≦0.990 (7)

Description

Non-directional electromagnetic steel plate

Field of Invention This invention relates to a non-directional electromagnetic steel plate.

Background of the Invention Non-directional electromagnetic steel sheets, such as those used in motor cores, require excellent magnetic properties in the direction parallel to their surface, such as low iron loss and high magnetic flux density.

For this purpose, it is advantageous to control the aggregate structure of the steel plate so that the easy magnetization axis (<100> orientation) of the crystals is aligned in the direction within the plate surface. Regarding this aggregate structure control, many techniques for controlling the {100} orientation, {110} orientation, {111} orientation, etc., have been disclosed, such as those described in Patents 1 to 5.

Various methods have been developed as a means of controlling aggregate structure, including the technique of utilizing strain-induced grain growth. Strain-induced grain growth under specific conditions can suppress aggregation in the {111} orientation, which does not have a good magnetization axis within the plate surface. Therefore, it has been effectively used in non-directional electromagnetic steel plates. These techniques are disclosed in patent documents 6-10, etc.

However, while the learned method can suppress the accumulation in the {111} direction, the {110}<001> direction (hereinafter, the Gaussian direction) will grow. The magnetic properties in one direction of the Gaussian direction are superior to those in {111}, but the overall circumferential magnetic properties are hardly improved. Therefore, the learned method suffers from the problem of failing to obtain superior magnetic properties in the overall circumferential aspect.

Furthermore, in order to achieve excellent magnetic properties across the entire circumference, patents 11-13 disclose techniques for developing the {100} crystal orientation or the {411} crystallization method in a compositional system that produces a γ→α phase transformation. Regarding these techniques, by assembling a steel composition with a low γ→α phase transformation temperature and transforming it at a low temperature, a fine-grained α phase structure is achieved at the hot roll forming time point. From the viewpoint of lowering the transformation temperature, delaying recovery recrystallization, and promoting strain accumulation, γ-stabilizing elements such as Mn, Cu, and Ni are actively added. However, Mn is known to be a segregating element. If the amount added increases, segregation will occur in the center of the hot roll plate thickness, which will cause the hot roll plate to crack during cold rolling.

[Previous Art Documents] [Patent Documents] [Patent Document 1] Japanese Patent Application Publication No. 2017-193754 [Patent Document 2] Japanese Patent Application Publication No. 2011-111658 [Patent Document 3] International Publication No. 2016/148010 [Patent Document 4] Japanese Patent Application Publication No. 2018-3049 [Patent Document 5] International Publication No. 2015/199211 [Patent Document 6] Japanese Patent Application Publication No. Hei 8-143960 [Patent Document 7] Japanese Patent Application Publication No. 2002-363713 [Patent Document 8] Japanese Patent Application Publication No. 2011-162821 [Patent Document 9] Japanese Patent Application Publication No. 2013-112853 [Patent Document 10] Japanese Patent Publication No. 4029430 [Patent Document 11] International Publication No. 2021/095846 [Patent Document 12] International Publication No. 2021/095851 [Patent Document 13] International Publication No. 2021/095880

Summary of the Invention [Problem to be Solved by the Invention] This invention addresses the aforementioned problems by providing a non-directional electromagnetic steel plate with a chemical composition that suppresses Mn and ensures appropriate amounts of Cu and Ni to avoid rollability issues. Furthermore, it possesses excellent magnetic properties with low in-plane anisotropy and omnidirectional average magnetic properties.

[Methods for Solving the Problem] The inventors have researched a technique for forming a suitable aggregate structure for non-directional electromagnetic steel plates by utilizing strain-induced grain growth. Specifically, they focused on the fact that grains in the {411}<uvw> orientation (hereinafter referred to as the {411} orientation) are similar in size to grains in the {100}<uvw> orientation (hereinafter referred to as the {100} orientation) and are less prone to strain. That is, by increasing the number of grains in the {411} orientation compared to the {100} orientation during the strain-induced grain growth stage, strain-induced grain growth is achieved primarily through the {411} orientation grains consuming the {111} orientation grains, while simultaneously suppressing the development of the {100} orientation grains. This allows for the production of an omnidirectional electromagnetic steel plate with the {411} orientation as the dominant orientation. It can be seen that if the development of the {100} orientation grains is sufficiently suppressed, and the {411} orientation is predominantly used, the overall circumferential average magnetic properties (average along the roll direction, width direction, directions at 45 degrees relative to the roll direction, and directions at 135 degrees relative to the roll direction) can be improved.

Furthermore, the inventors have studied a method to ensure that there are more grains in the {411} orientation than in the {100} orientation during the stage before strain-induced grain growth occurs. The method found is as follows: for steel grades with low contents of Mn, Ni, or Cu, hot rolling is performed under specific conditions, followed by cold rolling and annealing, and then cold rolling again at a low shrinkage rate (quenching and tempering rolling), and finally annealing.

Based on this knowledge and understanding, the inventors conducted further in-depth research and came up with various forms of invention as shown below.

(1) One embodiment of the non-directional electromagnetic steel plate of the present invention has the following chemical composition: by mass%, it contains C: less than 0.0100%, Si: 1.50% to 4.00%, sol.Al: 0.0001% to 1.0%, S: less than 0.0100%, N: less than 0.0100%, Mn: more than 0.10%, one or more of Mn, Ni, and Cu: total less than 2.50%, Mo: 0.0% to less than 2.5%, Cr: 0.0% to less than 2.5%, Ti: 0.000% to 0.005%, Nb: 0.000% to 0.005%, Sn: 0.000% to 0.400%, Sb: 0.000% to 0.400%. P: 0.000%～0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%～0.0100%, with C content (in mass%) set as [C], Mo content as [Mo], Cr content as [Cr], Mn content as [Mn], Ni content as [Ni], Cu content as [Cu], Si content as [Si], sol.Al content as [sol.Al], and P content as [P]. In this case, the transformation temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C, and the remainder consists of Fe and impurities; Furthermore, when observing the surface parallel to the steel plate surface using EBSD, the total area is set to S _tot. The area of the {411} orientation grain is set as S ₄₁₁ , the area of the {100} orientation grain is set as S ₁₀₀ , the area of the orientation grain with a Taylor factor M exceeding 2.9 according to the following formula (2) is set as _Styl , the total area of the orientation grains with a Taylor factor M less than 2.9 is set as _Stra , the average KAM value of the {411} orientation grain is set as K ₄₁₁ , and the average KAM value of the orientation grains with a Taylor factor M exceeding 2.9 is set as K _tyl . In this case, the following formulas (3) and (4) to (7) are satisfied. Ar ₃ (℃)＝1020-325×[C]+33×[Si]+287×[P]+80×[sol.Al]-120×([Mn]+[Mo]+[Cu])-46×([Cr]+[Ni])・・・(1) M＝(cosϕ×cosλ) ^-1・・・(2) S ₄₁₁ /S ₁₀₀ ＞1.00・・・(3) 0.20≦S _tyl /S _tot ≦0.85・・・(4) 0.05≦S ₄₁₁ /S _tot ≦0.80・・・(5) S ₄₁₁ /S _tra ≧0.50・・・(6) K ₄₁₁ /K _tyl ≦0.990・・・(7) Here, in equation (2), ϕ represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal. (2) The non-directional electromagnetic steel plate of one embodiment of the present invention has the following chemical composition: by mass%, it contains C: less than 0.0100%, Si: 1.50% to 4.00%, sol.Al: 0.0001% to 1.0%, S: less than 0.0100%, N: less than 0.0100%, Mn: more than 0.10%, one or more of Mn, Ni, Co, Pt, Pb, Au, and Cu: total less than 2.50%, Mo: 0.0% to less than 2.5%, Cr: 0.0% to less than 2.5%, Ti: 0.000% to 0.005%, Nb: 0.000% to 0.005%, Sn: 0.000% to 0.400%, Sb: 0.000% to 0.400%. P: 0.000%～0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%～0.0100%, and the C content in mass% is set as [C], Mo content as [Mo], Cr content as [Cr], Mn content as [Mn], Ni content as [Ni], Cu content as [Cu], Si content as [Si], sol.Al content as [sol.Al], and P content as [P]. At this time, the transformation temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C, and the remainder consists of Fe and impurities; Furthermore, when observing the surface parallel to the steel plate surface using EBSD, the total area is set as S. The area of the {411} oriented grain is set _as S ₄₁₁ , the area of the {100} oriented grain is set as S ₁₀₀ , the area of the oriented grain with a Taylor factor M exceeding 2.9 according to the following formula (2) is set as S _tyl , the total area of the oriented grains with a Taylor factor M less than 2.9 is set as S _tra , the average KAM value of the {411} oriented grain is set as K ₄₁₁ , and the average KAM value of the oriented grains with a Taylor factor M exceeding 2.9 is set as K _tyl . In this case, the following formulas (3) and (4) to (7) are satisfied. Ar ₃ (℃)＝1020-325×[C]+33×[Si]+287×[P]+80×[sol.Al]-120×([Mn]+[Mo]+[Cu])-46×([Cr]+[Ni])・・・(1) M＝(cosϕ×cosλ) ^-1・・・(2) S ₄₁₁ /S ₁₀₀ ＞1.00・・・(3) 0.20≦S _tyl /S _tot ≦0.85・・・(4) 0.05≦S ₄₁₁ /S _tot ≦0.80・・・(5) S ₄₁₁ /S _tra ≧0.50・・・(6) K ₄₁₁ /K _tyl ≦0.990・・・(7) Here, in equation (2), ϕ represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal. (3) The non-directional electromagnetic steel plate of one embodiment of the present invention has the following chemical composition: by mass%, it contains C: less than 0.0100%, Si: 1.50% to 4.00%, sol.Al: 0.0001% to 1.0%, S: less than 0.0100%, N: less than 0.0100%, Mn: more than 0.10%, one or more of Mn, Ni, and Cu selected: total less than 2.50%, Mo: 0.0% to less than 2.5%, Cr: 0.0% to less than 2.5%, Ti: 0.000% to 0.005%, Nb: 0.000% to 0.005%, Sn: 0.000% to 0.400%, Sb: 0.000% to 0.400%. P: 0.000%～0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%～0.0100%, with C content (in mass%) set as [C], Mo content as [Mo], Cr content as [Cr], Mn content as [Mn], Ni content as [Ni], Cu content as [Cu], Si content as [Si], sol.Al content as [sol.Al], and P content as [P]. In this case, the transformation temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C, and the remainder consists of Fe and impurities; Furthermore, when observing the surface parallel to the steel plate surface using EBSD, the total area is set to S _tot. The area of the {411} orientation grain is set as S ₄₁₁ , the area of the {100} orientation grain is set as S ₁₀₀ , the area of the orientation grain with a Taylor factor M exceeding 2.9 according to the following formula (2) is set as _Styl , and the total area of the orientation grains with a Taylor factor M of less than 2.9 is set as _Stra . In this case, the following formulas (8) to (11) are satisfied. Ar ₃ (℃)＝1020－325×[C]＋33×[Si]＋287×[P]＋80×[sol.Al]－120×([Mn]＋[Mo]＋[Cu])－46×([Cr]＋[Ni])・・・(1) M＝(cosϕ×cosλ) ^-1・・・(2) S ₄₁₁ /S ₁₀₀ ＞2.00・・・(8) S _tyl /S _tot ＜0.55・・・(9) S ₄₁₁ /S _tot ＞0.30・・・(10) S ₄₁₁ /S _tra ≧0.60・・・(11) Here, in formula (2), ϕ represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal. (4) The non-directional electromagnetic steel plate of one embodiment of the present invention has the following chemical composition: by mass%, it contains C: less than 0.0100%, Si: 1.50% to 4.00%, sol.Al: 0.0001% to 1.0%, S: less than 0.0100%, N: less than 0.0100%, Mn: more than 0.10%, one or more of Mn, Ni, Co, Pt, Pb, Au and Cu: total less than 2.50%, Mo: 0.0% to less than 2.5%, Cr: 0.0% to less than 2.5%, Ti: 0.000% to 0.005%, Nb: 0.000% to 0.005%, Sn: 0.000% to 0.400%, Sb: 0.000% to 0.400%. P: 0.000%～0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%～0.0100%, with C content (in mass%) set as [C], Mo content as [Mo], Cr content as [Cr], Mn content as [Mn], Ni content as [Ni], Cu content as [Cu], Si content as [Si], sol.Al content as [sol.Al], and P content as [P]. In this case, the transformation temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C, and the remainder consists of Fe and impurities; Furthermore, when observing the surface parallel to the steel plate surface using EBSD, the total area is set to S _tot. The area of the {411} orientation grain is set as S ₄₁₁ , the area of the {100} orientation grain is set as S ₁₀₀ , the area of the orientation grain with a Taylor factor M exceeding 2.9 according to the following formula (2) is set as _Styl , and the total area of the orientation grains with a Taylor factor M of less than 2.9 is set as _Stra . In this case, the following formulas (8) to (11) are satisfied. Ar ₃ (℃)＝1020－325×[C]＋33×[Si]＋287×[P]＋80×[sol.Al]－120×([Mn]＋[Mo]＋[Cu])－46×([Cr]＋[Ni])・・・(1) M＝(cosϕ×cosλ) ^-1・・・(2) S ₄₁₁ /S ₁₀₀ ＞2.00・・・(8) S _tyl /S _tot ＜0.55・・・(9) S ₄₁₁ /S _tot ＞0.30・・・(10) S ₄₁₁ /S _tra ≧0.60・・・(11) Here, in formula (2), ϕ represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal.

[Invention Effects] According to the aforementioned description of this invention, a non-directional electromagnetic steel plate can be provided. This plate has a chemical composition that suppresses the addition of Mn and ensures appropriate amounts of elements such as Cu and Ni to avoid rollability problems. Furthermore, it possesses excellent magnetic properties with low in-plane anisotropy and excellent circumferential (all-directional) average magnetic properties.

Forms for Implementing the Invention The non-directional electromagnetic steel sheet of this embodiment is manufactured by performing hot rolling, cold rolling, intermediate annealing, and tempering rolling processes on steel having the chemical composition described later. Furthermore, another embodiment of the non-directional electromagnetic steel sheet of the invention is manufactured by performing cold rolling, intermediate annealing, tempering rolling, and final annealing processes on steel having the chemical composition described later. This embodiment of the non-directional electromagnetic steel sheet achieves rollability by limiting the amount of Mn added to a low level, further adjusting the composition, and then optimizing the hot rolling conditions to form an appropriate α-processed grain structure during the hot rolling stage. This allows the {411} oriented grains to develop during subsequent cold rolling and intermediate annealing processes. By ensuring that the {411} oriented grains outnumber the {100} oriented grains in the stage before strain-induced grain growth, strain-induced grain growth primarily results in the {411} oriented grains consuming the {111} oriented grains, while simultaneously suppressing the development of {100} oriented grains, thereby manufacturing a non-directional electromagnetic steel sheet with the {411} oriented orientation as the predominant orientation. The final annealing following temper rolling induces strain in the steel sheet, promoting both strain-induced and/or normal grain growth. Furthermore, by sufficiently suppressing the development of grains in the {100} orientation, the {411} orientation is enriched. This effectively reduces the in-plane anisotropy of the magnetic properties and improves the overall circumferential (all-directional) average.

Furthermore, the steel sheet after tempering and quenching is related to the original sheet after strain-induced grain growth and normal grain growth. Hereinafter, regardless of whether it is before or after final annealing, the steel sheet after tempering and quenching, strain-induced grain growth and normal grain growth are all described as non-directional electromagnetic steel sheets.

Furthermore, in the non-directional electromagnetic steel sheet of this embodiment, by making the number of grains centered at the {411} orientation (hereinafter referred to as {411} orientation grains) greater than the number of grains at the {100} orientation in the metal structure of the steel sheet before temper rolling, the {411} orientation grains are further increased during the subsequent temper rolling and final annealing processes, thereby improving the overall magnetic properties. In addition to the process described above, {411} orientation grains can also be increased before temper rolling.

First, the chemical composition of the non-directional electromagnetic steel sheet and the material used in the manufacturing method of this embodiment, namely the directional electromagnetic steel sheet, will be explained. Since the chemical composition does not change during rolling or heat treatment, the chemical composition of the directional electromagnetic steel sheet used as the material is the same as the chemical composition of the non-directional steel sheet obtained through each step. In the following explanation, the unit "%" for the content of each element in the non-directional electromagnetic steel sheet or steel refers to "mass %", unless otherwise specified.

Furthermore, in this specification, the numerical range indicated by "~" refers to the range including the values recorded before and after "~" as both the lower and upper limits. Also, it is obvious that the elements of the following embodiments can be combined separately. Furthermore, in the embodiments of this invention, "non-directional electromagnetic steel plate" naturally includes steel plates in coil or cut form, and also includes steel plates processed into specific shapes as materials for motor cores and other products (components), and steel plates further laminated after processing to form motor cores.

First, the chemical composition of the non-directional electromagnetic steel sheet and the steel used in the manufacturing method of the present invention will be explained. In the following description, the unit of content of each element in the non-directional electromagnetic steel sheet or steel, "%", refers to "mass %", unless otherwise specified. Furthermore, the chemical composition of the non-directional electromagnetic steel sheet indicates the content when the base material, excluding the coating, is set to 100%. Furthermore, in the numerical ranges described in this specification, the upper limit of one numerical range can be replaced by the upper limit of another numerical range, or by the values disclosed in the embodiments. Within the range of values specified in this specification, the lower limit of one range may be replaced by the lower limit of another range, or by the values disclosed in the embodiments.

The non-directional electromagnetic steel plate of this embodiment has the following chemical composition, which is capable of producing the ferroferro-Vostian ferrotransformation (hereinafter referred to as the α-γ transform), and by mass%, contains: C: 0.0100% or less, Si: 1.50% to 4.00%, sol.Al: 0.0001% to 1.0%, S: 0.0100% or less, N: 0.0100% or less, Mn: 0.10% or more, one or more of Mn, Ni, and Cu: totaling less than 2.50%, Mo: 0.0% to less than 2.5%, Cr: 0.0% to less than 2.5%, Ti: 0.000% to 0.005%, Nb: 0.000% to 0.005% Sn: 0.000%–0.400%, Sb: 0.000%–0.400%, P: 0.000%–0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%–0.0100%, further wherein the contents of C, Si, P, sol.Al, Mn, Mo, Cu, Cr, and Ni satisfy the conditions specified below, and the remainder consists of Fe and impurities.

In the non-directional electromagnetic steel plate of this embodiment, it is preferred to contain a total of less than 2.50% of one or more of Mn, Ni, Co, Pt, Pb, Au and Cu.

Examples of impurities include those contained in raw materials such as ores or waste, and those contained in the manufacturing process.

(C: Below 0.0100%) C increases iron loss or causes magnetic aging. Therefore, the lower the C content, the better. This phenomenon is particularly pronounced when the C content exceeds 0.0100%. Therefore, the C content is set below 0.0100%. Lowering the C content also helps to uniformly improve the magnetic properties in all directions within the plate surface. Furthermore, there is no particular lower limit for the C content; however, considering the cost of decarburization during refining, it is preferable to set it above 0.0005%.

(Si: 1.50%～4.00%) Si increases electrical resistance, reduces eddy current losses, lowers iron losses, or increases the voltage drop ratio, thus improving the workability of the stamped core. If the Si content is less than 1.50%, these effects cannot be fully achieved. Therefore, the Si content is set at 1.50% or higher. On the other hand, if the Si content exceeds 4.00%, the magnetic flux density decreases, or the excessive increase in hardness reduces workability, or cold rolling becomes difficult. Therefore, the Si content is set at 4.00% or lower.

(sol.Al: 0.0001%～1.0%) Sol.Al increases resistance, reduces eddy current losses, and lowers iron losses. Sol.Al also helps to increase the relative magnitude of magnetic flux density _B50 relative to saturation magnetic flux density. If the sol.Al content is less than 0.0001%, these effects cannot be fully obtained. Furthermore, Al also has a desulfurization promoting effect during steelmaking. Therefore, the sol.Al content is set at 0.0001% or more. On the other hand, if the sol.Al content exceeds 1.0%, the magnetic flux density decreases, or the voltage drop ratio decreases, resulting in reduced workability. Therefore, the sol.Al content is set at 1.0% or less. Moreover, sol.Al refers to acid-soluble Al that is soluble in acids, not _oxides such as _Al₂O₃ .

Here, the magnetic flux density B ₅₀ is the magnetic flux density in a magnetic field of 5000 A/m.

(S: 0.0100% or less) S is not an essential element, for example, it exists in steel as an impurity. S precipitates as fine MnS, thus inhibiting recrystallization and grain growth during annealing. Therefore, the lower the S content, the better. When the S content exceeds 0.0100%, the increase in iron loss and decrease in magnetic flux density caused by inhibiting recrystallization and grain growth become particularly significant. Therefore, the S content is set to be 0.0100% or less. Furthermore, there is no particular limitation on the lower limit of the S content; considering the cost of desulfurization treatment during refining, it is preferable to set it to 0.0003% or more.

(N: Below 0.0100%) Like C, N degrades magnetic properties; therefore, a lower N content is better. Thus, the N content is set below 0.0100%. Furthermore, while there is no specific lower limit for the N content, considering the cost of denitrification during refining, it is preferable to set it above 0.0010%.

(Selected from one or more of Mn, Ni, and Cu: total not exceeding 2.50%) If the total content of Mn, Ni, and Cu exceeds 2.5%, the anisotropy of the magnetic properties increases. Therefore, the total content of Mn, Ni, and Cu is set to be less than 2.5%. The reason for the increased anisotropy is not yet clear, but it is believed to be due to its influence on the slip deformation of the granular iron region, promoting the formation and recrystallization of the {100} orientation. Furthermore, from this perspective, the increase in the content of alloying elements is preferably 2.3% or less. There is no particular limitation on the lower limit of the total content of Mn, Ni, and Cu; for example, it can be set to 0.10% or more, or 0.50% or more, or 1.00% or more, and further, it can be set to 2.00% or more.

(Selected from one or more of Mn, Ni, Co, Pt, Pb, Au, and Cu: total not exceeding 2.50%) Besides Mn, Ni, and Cu, Co, Pt, Pb, and Au also increase the anisotropy of magnetic properties. Therefore, in this embodiment, it is preferable to control the total content of these elements to not exceeding 2.50%. Furthermore, since these elements reduce magnetic flux density, it is preferable to set the total content to not exceeding 2.00%. There are no particular restrictions on the lower limit of the total content of Mn, Ni, Co, Pt, Pb, Au, and Cu; for example, it can be set to 0.10% or more, 0.50% or more, or 1.00% or more, and further, 2.00% or more. In particular, the alloying cost of Co, Pt, Pb, and Au is high; therefore, their active addition should be avoided. Furthermore, considering that controlling the transformation point _{of Ar3} is a characteristic of this embodiment, it is preferable to control the transformation point of _Ar3 by containing Mn, Ni, and Cu. Therefore, the total amount of Co, Pt, Pb, and Au does not reach 0.5%, and more preferably is below 0.1%. In further respects, the mixing is controlled within the range of unavoidable elements, so there is no need to add them actively (it can be set to 0%).

Furthermore, the non-directional electromagnetic steel plate and steel of this embodiment meet the following conditions as conditions for generating α-γ transformation. That is, the C content (in mass %) is set as [C], the Mo content as [Mo], the Cr content as [Cr], the Mn content as [Mn], the Ni content as [Ni], the Cu content as [Cu], the Si content as [Si], the sol.Al content as [sol.Al], and the P content as [P]. At this time, the transformation temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C.

Ar ₃ (℃)＝1020-325×[C]+33×[Si]+287×[P]+80×[sol.Al]-120×([Mn]+[Mo]+[Cu])-46×([Cr]+[Ni])・・・(1)

When the aforementioned equation (1) is not satisfied, even if α-γ transformation occurs, the transformation point is not within a suitable temperature range. Therefore, even if the manufacturing method described later is used, sufficient magnetic flux density cannot be obtained. If the transformation point _{of Ar3} does not reach 750°C, the temperature of the hot roll will become low, thus the deformation resistance will increase, the load on the roll mill will become too large, and the amount of element added will increase. Therefore, the toughness of the hot roll plate and the cold roll plate will also decrease. Therefore, 750°C is taken as the lower limit. On the other hand, if the transformation point of Ar ₃ exceeds 1050°C, the temperature of the hot roller becomes too high, thus requiring extremely high heating, which increases the load on the heating furnace, or it becomes a composition system that does not produce γ→α transformation. Therefore, 1050°C is set as the upper limit.

(Mn: 0.10% or more) Mn lowers the transformation point of _Ar3 , enabling grain refinement of the hot-rolled sheet in the composition system of the non-directional electromagnetic steel sheet of this embodiment through phase transformation. Mn is an element that increases the electrical resistance of steel and reduces iron loss. Therefore, it contains 0.1% or more Mn. From this perspective, it is preferable to contain 0.5% or more Mn. More preferably, it is 1.0% or more. On the other hand, Mn is an element that is prone to segregation. If the content increases, segregation will lead to cracking during cold working. Moreover, it will reduce the saturation magnetic flux density, thus hindering the increase of the magnetic flux density of the steel sheet. Furthermore, excessive formation of MnS leads to reduced cold workability. Therefore, the upper limit of Mn content is set to less than 2.5%. The upper limit of Mn content is preferably below 2.3% by mass, and more preferably 2.0% by mass.

(The total amount of Cu and the aforementioned elements does not reach 2.5%) Like Mn, Cu is an element that increases the electrical resistance of the steel plate and reduces iron loss. It also lowers the transformation point of _Ar3 . In the chemical composition of the non-directional electromagnetic steel plate of this embodiment, it is an element that can achieve particle size reduction in hot-rolled steel plates through phase transformation. However, if the Cu content is high, the increase in recrystallization temperature will adversely affect the formation of the aggregate structure during annealing after cold rolling, and become a cause of embrittlement during hot working. Moreover, it will also reduce the saturation magnetic flux density and hinder the increase of the magnetic flux density of the steel plate. Therefore, this needs to be taken into account. Furthermore, by adding Ni at more than half the amount of Cu, the embrittlement caused by Cu during hot working can be reduced. There is no upper limit to the Cu content; it is set to be less than 2.5%. However, the upper limit of the Cu content is preferably 1.5% by mass or less, and more preferably 1.0% by mass or less. There is no particular restriction on the lower limit of the Cu content; for example, it can be set to 0.01% or more.

(The total amount of Ni and the aforementioned elements does not reach 2.5%) Similarly, Ni, like Mn, increases the electrical resistance of the steel plate and reduces iron loss. Ni further lowers the A3 transformation point, enabling grain refinement through phase transformation in the chemical composition of the non-directional electromagnetic steel plate of this embodiment. However, if the Ni content is too high, the manufacturing cost increases due to Ni's high price. Furthermore, it reduces the saturation magnetic flux density, hindering the increase of the steel plate's magnetic flux density. Therefore, these factors should be considered when designing the content. There is no upper limit to the Ni content; it is set to be less than 2.5%. Preferably, the upper limit of the Ni content is 1.0% by mass or less, and more preferably 0.7% by mass or less. There is no particular limitation on the lower limit of the Ni content; for example, it can be set to 0.01% or more.

(Mo: 0.0% to less than 2.5%) Mo is an element that lowers the transformation point of _Ar3 and, in the chemical composition of the non-directional electromagnetic steel sheet of this embodiment, enables the finer particle size of the hot-rolled sheet through phase transformation. Therefore, Mo can be included as needed, preferably at 0.1% or more. On the other hand, containing more than 2.5% Mo will significantly reduce cold workability; therefore, the Mo content is set to less than 2.5%.

(Cr: 0.0% to less than 2.5%) Cr lowers the transformation point of _Ar3 . In the chemical composition of the non-directional electromagnetic steel sheet of this embodiment, it is an element that can achieve particle size refinement of hot-rolled steel sheets through phase transformation, and it also has the effect of strength adjustment or corrosion resistance. In addition, it has the effect of particularly improving high-frequency characteristics. Therefore, Cr can be included as needed, preferably at 0.1% or more. On the other hand, excessive Cr will saturate the effect, increase the raw material cost, and reduce the saturation magnetic flux density, hindering the increase of the magnetic flux density of the steel sheet. Therefore, the Cr content is set to less than 2.5%.

(Ti: 0.000%～0.005%) Ti, existing in solid solution or as TiN, suppresses recrystallization and helps achieve finer grain size in Vostian iron. Therefore, Ti can be included as needed, preferably at 0.001% or more. On the other hand, if the Ti content exceeds 0.005%, various precipitates such as TiN, TiS, and TiC will form, deteriorating iron loss characteristics; therefore, the content is set to 0.005% or less.

(Nb: 0.000%～0.005%) Nb, existing in solid solution or as NbN, inhibits recrystallization, contributing to the miniaturization of Vostian iron grains. Therefore, Nb can be included as needed, preferably at 0.001% or more. On the other hand, if the Nb content exceeds 0.005%, various precipitates such as NbN and NbC will form, deteriorating iron loss characteristics; therefore, the content is set to 0.005% or less.

(Sn: 0.000%～0.400%, Sb: 0.000%～0.400%, P: 0.000%～0.400%) Sn or Sb improves the microstructure of steel after cold rolling and recrystallization, increasing its magnetic flux density. Therefore, these elements can be included as needed; however, excessive amounts will make the steel brittle. Therefore, the Sn and Sb contents are both set to 0.400% or less. P can also be included to ensure the hardness of the recrystallized steel sheet; however, excessive amounts will lead to embrittlement. Therefore, the P content is set to 0.400% or less.

When further effects such as imparting magnetic properties are desired, it is preferable to contain one or more of the following: Sn, Sb, and P, selected from the group consisting of 0.020% to 0.400% Sn, 0.020% to 0.400% Sb, and 0.020% to 0.400% P.

(Selected from one or more elements in the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000% to 0.0100%) Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd react with sulfur in the molten steel during casting to form sulfides, oxysulfides, or both. Hereinafter, Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd are sometimes collectively referred to as "coarse precipitate-forming elements." The particle size of precipitates from coarse precipitate-forming elements is approximately 1 μm to 2 μm, much larger than the particle size (approximately 100 nm) of fine precipitates such as MnS, TiN, AlN, TiC, and NbC. Therefore, these fine precipitates adhere to the precipitates of coarse precipitate-forming elements, making it difficult to suppress recrystallization and grain growth during annealing processes such as intermediate annealing. To fully achieve these effects, the total content of coarse precipitate-forming elements is preferably 0.0005% or more. However, if the total content of these elements exceeds 0.0100%, the amount of sulfides or oxysulfides, or both, becomes excessive, suppressing recrystallization and grain growth during annealing processes such as intermediate annealing. Therefore, the total content of coarse precipitate-forming elements is set to 0.0100% or less.

In this embodiment, the remaining portion of the chemical composition other than those mentioned above may be Fe and impurities. Impurities refer to elements mixed in during the steel raw materials and/or steelmaking process. Furthermore, other elements may be included to replace a portion of Fe without impairing the effects of the invention. For example, less than 0.10% of B, O, V, Bi, W, and Y may be included. Moreover, the total amount of impurities is preferably less than 5.00%, and more preferably less than 1.00%.

The chemical composition can be determined using the following methods. The chemical composition can be determined using common analytical methods for steel. For example, the chemical composition can be determined using ICP-AES (Inductively Coupled Plasma-Atomic Emission Spectrometry). Specifically, under conditions based on a pre-prepared calibration curve, a sample taken from a steel plate is measured using a specified measuring apparatus to identify the chemical composition. C and S can be determined using combustion-infrared absorption, N can be determined using inert gas melting thermal conductivity, and O can be determined using inert gas melting-non-dispersive infrared absorption. In cases where the surface has an insulating film, it can be mechanically removed using a minitor before analysis.

Secondly, the thickness of the non-directional electromagnetic steel plate of this embodiment will be explained. There is no particular limitation on the thickness of the non-directional electromagnetic steel plate of this embodiment. The thickness of the non-directional electromagnetic steel plate of this embodiment is preferably 0.10 to 0.50 mm. Generally, the thinner the plate, the lower the iron loss, but the lower the magnetic flux density. In this regard, if the plate thickness is 0.10 mm or more, the iron loss becomes even lower, and the magnetic flux density becomes even higher. Furthermore, if the plate thickness is 0.50 mm or less, low iron loss can be maintained.

Next, the metal structure of the non-directional electromagnetic steel plate of this embodiment will be explained. Hereinafter, the metal structure of each embodiment of the non-directional electromagnetic steel plate will be specified based on the metal structure after tempering and rolling and the metal structure after final annealing.

First, the specific metal structure and the specific method thereof will be explained. The metal structure specified in this embodiment is specified in a cross section parallel to the surface of the steel plate, and is specified in the following steps.

First, the sample was ground until 7/8 of its thickness was reached, exposing the 1/8 thickness section. The ground surface (the surface after 1/8 of the steel plate was ground) was observed using SEM at an accelerating voltage of 25kV and a magnification of 1000x via EBSD (Electron Back Scattering Diffraction). Regarding the observation field, the sample after tempering and rolling was set at 500μm × 500μm, and the sample after relaxation annealing was set at 2000μm × 2000μm. Observations could be made at several locations within these divided sections. Regarding the step interval during measurement, the sample after tempering and rolling was set at 0.3μm, and the sample after relaxation annealing was set at 2.0μm. Based on EBSD observation data, the following types of areas and KAM (Kernel Average Misorientation) values are obtained using conventional methods. The area in each direction can be calculated by using IPF (Inverse Pole Figure) from the EBSD observation field of view. The KAM value can be obtained by calculating the azimuth difference between measurement points using software such as OIM Analysis. In this invention, OIM Analysis 7.3 is used, and the tolerance included in the KAM value is set to less than 5° of the azimuth difference from adjacent pixels. The azimuth difference between the ^1st neighbor measurement points is calculated, and the average of the obtained values is used as the KAM value. Furthermore, the setting "Set zero point kernel to maximum misorientations" is retained as the default value and selected.

S _tot : Total area (observation area) S _tyl : Total area of grains with a Taylor factor M exceeding 2.9 according to Equation (2) S _tra : Total area of grains with a Taylor factor M less than 2.9 according to Equation (2) S ₄₁₁ : Total area of grains in the {411} orientation S ₁₀₀ : Total area of grains in the {100} orientation K _tyl : Average KAM value of grains with a Taylor factor M exceeding 2.9 according to Equation (2) K ₄₁₁ : Average KAM value of grains in the {411} orientation Here, the orientation margin of the crystal plane orientation is set to 10°. Furthermore, in the following, when recording a specific crystal plane orientation, the orientation margin will also be set to 10°. That is, a grain having a face orientation within ±10° of the specific face orientation described in this invention is considered to have that specific crystal orientation.

Here, the Taylor factor M is based on the following equation (2). M＝(cosϕ×cosλ) ^-1・・・(2) ϕ: the angle between the stress vector and the sliding direction vector of the crystal λ: the angle between the stress vector and the normal vector of the sliding surface of the crystal

Assuming that the aforementioned Taylor factor M is the Taylor factor of the crystal sliding deformation occurring on the sliding surface {110} or {112}, and the sliding direction <111>, then no deformation occurs in the width direction of the plate, but compression deformation occurs in the thickness direction and elongation deformation occurs in the rolling direction.

Here, we explain the method for determining the Taylor factor using SEM-EBSD data and OIM Analysis 7.3. Based on the chart creation function of OIM Analysis 7.3, select (Taylor Factor) as the object (Type). The detailed conditions for determining the Taylor factor are as described above. As the phase of the sliding system, select Iron (Alpha). As the sliding system, input the following two values: Sliding surface: 101, Sliding direction: 11-1, CRSS: 0.2 Sliding surface: 112, Sliding direction: 11-1, CRSS: 0.2 Furthermore, if the sliding surface and sliding direction are selected with a product of 0, the same result can be obtained even if the numerical order and signs are different. The CRSS (Critical Resolved Shear Stress) value is the same in both sliding systems. The Deformation Gradient is input as the tensor of the following roll deformation: RD, TD, ND RD 1 0 0 TD 0 0 0 ND 0 0 -1 The Taylor factor of all measured points under these conditions is calculated in the form of a histogram. Based on this result, the area fraction of oriented grains with a Taylor factor of 2.9 or higher and those with a Taylor factor below 2.9 can be converted.

Secondly, in the following implementation methods 1 to 2, the characteristics are defined by the aforementioned area and KAM value.

(Implementation Method 1) First, the microstructure of the non-directional electromagnetic steel sheet after temper rolling is explained. This microstructure accumulates sufficient strain to induce strain-induced grain growth, and can be positioned in the early stage before strain-induced grain growth occurs. The characteristics of the microstructure of the steel sheet after temper rolling are generally determined by the orientation of the grains in the target orientation and the conditions related to strain accumulation sufficient to induce strain-induced grain growth.

Regarding the non-directional electromagnetic steel plate of Embodiment 1, the area of the grains in each direction satisfies the following formulas (3) and (4) to (6). S ₄₁₁ /S ₁₀₀ ＞1.00・・・(3) 0.20≦S _tyl /S _tot ≦0.85・・・(4) 0.05≦S ₄₁₁ /S _tot ≦0.80・・・(5) S ₄₁₁ /S _tra ≧0.50・・・(6)

As for the preferred orientation grains for growth, the {411} orientation grains have been described as the center. However, there are many other orientation grains, which, like the {411} orientation grains, have relatively small Taylor factors and are less prone to accumulating processing strain, and can preferentially grow during strain-induced grain growth. Among them, the {100} orientation is an orientation that is easily found in non-directional electromagnetic steel sheets. This orientation grains compete with the preferred {411} orientation grains. On the other hand, the orientation of this orientation grains is not easily controlled randomly within the steel sheet surface. If strain-induced grain growth leads to the development of the {100} orientation, an undesirable situation occurs where the in-plane anisotropy of the steel sheet increases. Therefore, in Embodiment 1, it is stipulated that the presence ratio of {411} oriented grains is ensured in orientations where the Taylor factor is relatively small and processing strain is not easily accumulated. The area ratio S ₄₁₁ / S ₁₀₀ exceeds 1.00. That is, the presence of {411} oriented grains is greater than that of {100} oriented grains. If, on the basis of sufficiently suppressing the development of {100} oriented grains, {411} oriented grains are the dominant orientation, the magnetic properties of the entire circumference average (average of the roll direction, width direction, direction at 45 degrees relative to the roll direction, and direction at 135 degrees relative to the roll direction) are improved. Preferably, the area ratio S ₄₁₁ / S ₁₀₀ is 2.0 or higher, and more preferably, the area ratio S ₄₁₁ / S ₁₀₀ is 3.0 or higher.

There is no particular upper limit to the area ratio S ₄₁₁ / S _100. For the purposes of this invention, it is perfectly acceptable even if the presence of {100} orientation grains is zero and the value of the area ratio S ₄₁₁ / S ₁₀₀ is infinitely large. However, in practice, having zero {100} orientation grains would introduce a significant manufacturing load; therefore, the area ratio S ₄₁₁ / _{S 100 is} preferably 20 or less, _and more preferably 10 or less.

Furthermore, _Styl represents the quantity of orientations with a relatively large Taylor factor. During strain-induced grain growth, orientations with small Taylor factors and low processing strain accumulation tend to grow preferentially, while simultaneously eroding the growth of orientations with large Taylor factors and accumulated processing strain. Therefore, a certain amount of _Styl is necessary for the development of specific orientations through strain-induced grain growth. In Embodiment 1, the area ratio _Styl / _Stot is specified to be 0.20 or higher relative to the _total area. If the area _{ratio Styl / Stot} is less than 0.20, the target crystal orientation will not be fully developed through strain-induced grain growth. The area ratio _Styl /S _tot is preferably above 0.30, and even better above 0.50.

The upper limit of the area ratio S _{_tyl} /S_{_tot} is related to the amount of grains in the strain-induced grain growth step described below, but this condition is not simply determined by the ratio of the preferred growth orientation to the eroded orientation. First, as mentioned below, since the area ratio S_₄₁₁ /S _{_tot} of {411} oriented grains to be developed by strain-induced grain growth is 0.05 or higher, the area ratio S_{_tyl}/S_{_tot} must be 0.95 or lower. However, if the amount of area ratio S_{_tyl} /S _{_tot} is too large, the {411} oriented grains will not grow preferentially due to the strain relationship described later. The relationship with strain will be described in detail later. In Embodiment 1, the area ratio _Styl / _Stot is 0.85 or less. Preferably, the area ratio _Styl / _Stot is 0.75 or less, and more preferably 0.70 or less.

In the strain-induced grain growth step described below, the {411} orientation grains are preferentially grown. The {411} orientation is an orientation with a relatively small Taylor factor and is less prone to accumulating processing strain, and this orientation can preferentially grow in the strain-induced grain growth step. In Embodiment 1, {411} orientation grains must exist, and in Embodiment 1, the area ratio S ₄₁₁ / S _tot of the {411} orientation grains is set to 0.05 or higher. If the area ratio S ₄₁₁ / S _tot of the {411} orientation grains does not reach 0.05, the {411} orientation grains will not fully develop with the help of subsequent strain-induced grain growth. The area ratio S ₄₁₁ / S _tot is preferably 0.10 or higher, and even better is 0.20 or higher.

The upper limit of the area ratio S _₄₁₁ /S _{_tot} depends on the amount of grains in the {411} orientation that should be consumed by strain-induced grain growth. In Embodiment 1, the area ratio S_{_tyl}/S_{_tot} of orientations with a Taylor factor exceeding 2.9 that should be consumed by strain-induced grain growth is above 0.20, therefore, the area ratio S_₄₁₁ /S _{_tot} becomes below 0.80. However, when the amount of {411} orientation grains present before strain-induced grain growth is low, the advantage of grain growth becomes significant, and the {411} orientation grains can be more developed. Taking this into account, the area ratio of S ₄₁₁ /S _tot is preferably below 0.60, even better below 0.50, and further preferably below 0.40.

The {411} oriented grain has been described as the preferred orientation for growth, but many other oriented grains, like the {411} oriented grain, have relatively small Taylor factors and are less prone to accumulating processing strain, and can preferentially grow during strain-induced grain growth. These oriented grains compete with the preferred {411} oriented grain. On the other hand, such oriented grains are less numerous than those in the steel plate with the easy magnetization axis direction (<100> direction) being {411}, or it is difficult to selectively randomize the orientation within the steel plate. Therefore, if such orientations develop due to strain-induced grain growth, the magnetic properties deteriorate, or the anisotropy within the steel plate increases, resulting in undesirable conditions. Therefore, in Embodiment 1, it is specified that the presence ratio of {411} oriented grains is ensured in orientations with relatively small Taylor factors and where processing strain is not easily accumulated.

The area of oriented grains with a Taylor factor of 2.9 or less (including oriented grains considered to compete with {411} oriented grains in strain-induced grain growth) is set to S _{_tra} . Furthermore, as shown in Equation (6), the area ratio S_₄₁₁ /S _{_tra} is set to 0.50 or more to ensure the growth advantage of {411} oriented grains. If the area ratio S_₄₁₁ /S _{_tra} is less than 0.50, the {411} oriented grains will not fully develop with the aid of strain-induced grain growth. The area ratio S_₄₁₁ /S _{_tra} is preferably 0.80 or more, and more preferably 0.90 or more. On the other hand, there is no need to specifically limit the upper limit of the area ratio S ₄₁₁ / S _tra , and the orientation grains with a Taylor factor of 2.9 or less can all be {411} orientation grains (S ₄₁₁ / S _tra = 1.00).

In Embodiment 1, in addition to the crystal orientation described above, by combining the strain described below, the {411} orientation grains can be reliably grown, resulting in superior magnetic properties. In Embodiment 1, the strain-related requirements must satisfy the following equation (7). K ₄₁₁ / K _tyl ≦0.990・・・(7)

The requirements related to strain are defined by equation (7). Equation (7) is the ratio of the strain (average KAM value) accumulated in the {411} oriented grain to the strain (average KAM value) accumulated in the oriented grain with a Taylor factor exceeding 2.9. Here, the KAM value is the oriented difference between adjacent measurement points within the same grain, and the KAM value is higher in areas with more strain. From a crystallographic point of view, for example, in the case of compressive deformation in the thickness direction under planar strain in a plane parallel to the thickness direction and the rolling direction, i.e., in the case of simply rolling steel plates, the ratio of K ₄₁₁ to K _tyl , K ₄₁₁ / K _tyl, is usually less than 1. However, in reality, due to the constraints of adjacent grains, the presence of precipitates within the grains, and further, the influence of macroscopic deformation changes, including contact with tools (rollers, etc.) during deformation, the strain resulting from the crystal orientation observed in the microscopic form exhibits a wide variety of morphologies. Therefore, it is difficult to observe the influence of purely geometric orientation caused by the Taylor factor. Furthermore, for example, even grains with the same orientation can exhibit very large variations depending on grain size, grain morphology, the orientation or size of adjacent grains, the state of precipitates, and their position in the thickness direction. Moreover, even within a single grain, the strain distribution can vary significantly due to the formation of deformation zones near grain boundaries, within the grain, and other factors.

Taking this variation into account, in Embodiment 1, to obtain superior magnetic properties, _K411 / _Ktyl is set to 0.990 or less. If _K411 / _Ktyl exceeds 0.990, the specificity of the region to be eroded is lost, thus strain-induced grain growth is less likely to occur. _K411 / _Ktyl is preferably 0.970 or less, and more preferably 0.950 or less.

In the metal microstructure of the non-directional electromagnetic steel sheet after temper rolling in Embodiment 1, there is no particular lower limit on the grain size. This is because the relationship with grain size is not close when appropriate strain-induced grain growth is achieved through subsequent final annealing. That is, whether appropriate target strain-induced grain growth is achieved largely depends on the chemical composition of the steel sheet, the relationship between the amount (area) of grains in each crystal orientation, and the relationship between the amount of strain in each orientation.

However, if the grain size becomes too large, although strain-induced grain growth may occur, it will be difficult to induce sufficient grain growth within the actual temperature range. Furthermore, if the grain size becomes too large, it will be difficult to avoid deterioration of the magnetic properties. Therefore, the actual average grain size is preferably set to 300 μm or less. More preferably, it is 100 μm or less, further preferably 50 μm or less, and even more preferably 30 μm or less. The finer the grain size, the easier it is to identify the development of the target crystal orientation achieved by strain-induced grain growth, when the crystal orientation and strain distribution are properly controlled. However, if the grain size is too fine, as mentioned above, during the strain-imparting processing, the constraint of adjacent grains makes it difficult to form differences in the amount of strain per crystal orientation. From this perspective, the average grain size is preferably 3 μm or more, more preferably 8 μm or more, and even more preferably 15 μm or more.

(Implement 2) In Embodiment 1 above, the characteristics of the steel plate are defined by specifying the strain of the steel plate according to the KAM value. In contrast, in Embodiment 2, the steel plate obtained by further grain growth after annealing the steel plate described in Embodiment 1 for a sufficiently long time is specified. The strain-induced grain growth of this steel plate is essentially complete, and the strain is almost completely eliminated. Therefore, the characteristics of this steel plate are excellent. That is, the {411} orientation grains grow by means of strain-induced grain growth, and further, normal grain growth is carried out through final annealing until the strain is almost completely eliminated. The resulting steel plate has a stronger aggregation in the {411} orientation. In Embodiment 2, the crystal orientation and grain size of the steel plate obtained by heat treatment using the steel plate described in Embodiment 1 (i.e., the non-directional electromagnetic steel plate obtained by final annealing of a non-directional electromagnetic steel plate rolled by tempering and quenching rollers) are explained.

The crystal orientation of the steel plate obtained after final annealing satisfies the following formulas (8) to (11). The reason is that, for the non-directional electromagnetic steel plate after tempering and rolling, the numerical range of formula (8) is different from that of formula (3). By inducing grain growth through strain generated during the final annealing process, the {411} orientation grains grow further and their area increases, thereby improving the circumferential average (average of the rolling direction, width direction, direction at 45 degrees relative to the rolling direction, and direction at 135 degrees relative to the rolling direction) magnetic properties. Regarding the non-directional electromagnetic steel plate after heat-quenching and tempering, the values in equations (9) to (11) differ from those in equations (4) to (6). Grain growth is induced by strain generated during the final annealing process. The {411} orientation grains further grow, increasing their area. Furthermore, the {411} orientation grains with a Taylor factor exceeding 2.9 are primarily consumed by the {411} orientation grains, thus further reducing their area. S ₄₁₁ / S ₁₀₀ > 2.00・・・(8) S _tyl / S _tot < 0.55・・・(9) S ₄₁₁ / S _tot > 0.30・・・(10) S ₄₁₁ / S _tra ≧ 0.60・・・(11)

In Embodiment 2, the area ratio S_{_tyl} /S _{_tot} is set to less than 0.55. The total area S_{_tyl} can also be zero. The upper limit of the area ratio S _{_tyl} /S_{_tot} is determined as one of the parameters representing the degree of growth progress of {411} orientation grains. An area ratio S _{_tyl}/S_{_tot} of 0.55 or higher indicates that orientation grains with a Taylor factor exceeding 2.9 that should be consumed during the strain-induced grain growth stage have not been sufficiently consumed. In this case, the magnetic properties are not sufficiently improved. The area ratio S _{_tyl} /S _{_tot} is preferably 0.40 or lower, more preferably 0.30 or lower. The lower the area ratio S _{_tyl} /S _{_tot}, the better; therefore, no lower limit is specified, and it can also be 0.00.

Furthermore, in Embodiment 2, the area ratio S ₄₁₁ / S _tot is set to be greater than 0.30. If the area ratio S ₄₁₁ / S _tot is less than 0.30, the magnetic properties are not sufficiently improved. The area ratio S ₄₁₁ / S _tot is preferably 0.40 or more, and more preferably 0.50 or more. The case where the area ratio S ₄₁₁ / S _tot is 1.00 refers to a crystalline structure consisting entirely of {411} oriented grains, without any grains in other orientations, but this case is also considered in Embodiment 2.

In Embodiment 2, similarly to Embodiment 1, the relationship between the {411} oriented grains that compete with the {411} oriented grains during strain-induced grain growth is also important. When the area ratio S ₄₁₁ / S _tra is sufficiently large, the advantage of {411} oriented grain growth is also ensured under normal grain growth conditions after strain-induced grain growth, and the magnetic properties become good. If the area ratio S ₄₁₁ / S _tra is less than 0.60, the {411} oriented grains will not fully develop with the aid of strain-induced grain growth. Under normal grain growth conditions after strain-induced grain growth, oriented grains with small Taylor factors other than the {411} oriented grains will have grown to a considerable size, and the in-plane anisotropy of the magnetic properties will also increase. Therefore, in Embodiment 2, the area ratio S ₄₁₁ / S _tra is set to 0.60 or higher. The area ratio S ₄₁₁ / S _tra is preferably 0.70 or higher, and more preferably 0.80 or higher. On the other hand, there is no need to specifically limit the upper limit of the area ratio S ₄₁₁ / S _tra , and oriented grains with a Taylor factor of 2.9 or lower can also be {411} oriented grains.

Furthermore, there is no particular limitation on the range of average grain size. However, if the average grain size becomes too large, it will be difficult to avoid the deterioration of magnetic properties. Therefore, similar to Embodiment 1, in Embodiment 2, the actual average grain size of the relatively large grains, i.e., the {411} oriented grains, is preferably set to 500 μm or less. The average grain size of the {411} oriented grains is more preferably 400 μm or less, further preferably 300 μm or less, and even more preferably 200 μm or less. On the other hand, regarding the lower limit of the average grain size of the {411} orientation grains, assuming that sufficient eugenic growth of the {411} orientation is ensured, the average grain size of the {411} orientation grains is preferably 40 μm or more, more preferably 60 μm or more, and even more preferably 80 μm or more.

[Characteristics] The non-directional electromagnetic steel sheet after final annealing, due to the controlled chemical composition and metal structure as described above, achieves excellent magnetic properties (low iron loss) not only in the roll direction and width direction, but also on a circumferential average (average of the roll direction, width direction, direction at 45 degrees relative to the roll direction, and direction at 135 degrees relative to the roll direction). The aforementioned roll direction and width direction refer to the roll direction and width direction of the obtained non-directional electromagnetic steel sheet.

Of the three directions in which the non-directional electromagnetic steel plate of Embodiment 2 forms an angle of 0°, 45°, and 90° with respect to the rolling direction, the magnetic characteristics in the 45° direction are the best. In Embodiment 2, the magnetic characteristics in the 45° direction are the average of the magnetic characteristics in the two directions forming an angle of +45° and -45° with respect to the rolling direction.

When measuring the magnetic flux density of the non-directional electromagnetic steel plate of Embodiment 2, the magnetic flux density _B50 relative to the 45° direction of the rolling direction is preferably 1.75T or higher. Furthermore, in the non-directional electromagnetic steel plate of Embodiment 2, a high magnetic flux density relative to the 45° direction of the rolling direction allows for the acquisition of a magnetic flux density with low in-plane anisotropy and high overall circumferential (all-directional) average.

In the non-directional electromagnetic steel plate of Embodiment 2, when the magnetic flux density _B50 in the rolling direction is set to _B50L , the magnetic flux density _B50 in the direction at 45° relative to the rolling direction is set to _B50D , and the magnetic flux density _B50 in the direction at 90° relative to the rolling direction is set to _B50C , it is found that the magnetic flux density anisotropy is relatively high _{in B50D} and relatively low in _B50L and _B50C .

In the non-directional electromagnetic steel plate of Embodiment 2, it is preferable to use the average value of _B50D , _B50L and _B50C to satisfy the following formula (A).

｜B _50D －(B _50L ＋B _50C )/2｜≦0.2・・・(A)

There is no particular restriction on the lower bound of the left-hand side of the aforementioned equation (A), but it is preferable to be zero.

Magnetic flux density can be measured as follows: cut out a 55mm square sample from the direction of 45° or 0° relative to the roller direction, and measure it using a single-plate magnetic measuring device.

Magnetic measurements can be performed using the methods described in JIS C 2550-1 (2011) and JIS C 2550-3 (2019), or using the methods described in JIS C 2556 (2015). Furthermore, when the sample is too small to be measured using the methods described in the aforementioned JIS standards, the electromagnetic circuit can be used with a device capable of measuring a 55mm square sample or even smaller samples according to JIS C 2556 (2015).

Next, an example of the manufacturing method of the non-directional electromagnetic steel sheet of this embodiment will be described. The non-directional electromagnetic steel sheet of this embodiment is obtained by the following manufacturing method, which includes: hot rolling step, cold rolling step, intermediate annealing step, tempering rolling step, and final annealing step. The preferred conditions for each step will be described below. In this embodiment, the Ar ₃ temperature is the alteration temperature Ar ₃ (°C) specified by the aforementioned formula (1).

(Hot Rolling Step) In the hot rolling step, steel meeting the above chemical composition is hot-rolled to produce hot-rolled steel sheets. The hot rolling step includes a heating process and a rolling process.

The steel is, for example, a steel billet manufactured by conventional continuous casting, and the steel with the aforementioned composition is manufactured using well-known methods. For example, molten steel is produced using a converter or electric furnace. The produced molten steel is then subjected to secondary refining using degassing equipment to produce molten steel with the aforementioned chemical composition (the chemical composition does not undergo substantial changes in subsequent steps). Using the molten steel, steel billets are cast by continuous casting or ingot casting. The cast steel billets can also be rolled in sections.

During the heating process, it is preferable to heat the steel having the above-mentioned chemical composition to 1000–1200°C. Specifically, the steel is placed in a heating furnace or soaking furnace and heated inside the furnace. There is no particular limitation on the holding time at the aforementioned heating temperature in the heating furnace or soaking furnace, for example, it is 30–200 hours.

In the rolling process, heated steel is rolled through multiple passes to produce hot-rolled steel plates. Here, "pass" refers to the compression of the steel plate as it passes through a rolling mill with a pair of working rollers. Hot rolling can be performed, for example, using a tandem rolling mill with multiple rolling mills arranged in a row (each rolling mill has a pair of working rollers) to perform multiple passes, or using a reversible rolling mill with a pair of working rollers to perform multiple passes. From a productivity standpoint, it is preferable to use a tandem roller mill to perform multiple rolling passes.

The rolling process (roughing and final rolling) involves heating the aforementioned steel to perform hot rolling. The steel is, for example, a billet manufactured by conventional continuous casting. The billet is heated to a temperature above _Ar3 , within the range where the steel microstructure forms the γ phase. Hot rolling begins within the temperature range where the steel microstructure forms the γ phase (hereinafter, this temperature range is sometimes referred to as the γ zone). Except for the required number of passes, including the final rolling pass, all other passes are performed in the γ zone. The required number of passes, including the final rolling pass, are performed within the temperature range where the steel microstructure contains the α phase (hereinafter, this temperature range is sometimes referred to as the α zone), thus completing the hot rolling process. Generally, rough rolling and the section before and after final rolling are performed in the γ zone, and final rolling is performed in the α zone. In this embodiment, the shrinkage rate within the temperature range above _Ar3 temperature and below _Ar3 + 20°C before the final rolling in the α zone is set to 10% or more. Furthermore, regarding the shrinkage rate within the temperature range above the final rolling temperature FT but below the Ar ₃ temperature, taking into account the case of multiple rolling passes, it is set to a total of 15% or more. Moreover, the final rolling temperature FT refers to the surface temperature of the hot-rolled steel sheet immediately after final rolling. There is no particular limitation on the lower limit of the final rolling temperature FT; for example, it can be set to above Ar ₃ temperature - 100°C.

Rolling within a temperature range exceeding _Ar3 +20°C before the final rolling in the α region has almost no impact on the grain size of the pre-transformed γ grains. After transformation, coarse pre-transformed α grains are formed, which is unrelated to the aggregation towards the {411} crystal orientation in the final product. If the rolling rate within a temperature range above _Ar3 temperature and below _Ar3 +20°C before the final rolling in the α region is less than 10%, the strain accumulation of the pre-transformed γ grains towards the α region is insufficient, resulting in coarse pre-transformed α grains, making it difficult for aggregation towards the {411} crystal orientation to occur in the final product. The rolling rate within the temperature range above _Ar3 temperature and below _Ar3 +20℃ is preferably set to 15% or higher, and more preferably 20% or higher. There is no upper limit for the total rolling rate; setting it above 40% would result in excessive load on the rolling mill, so 40% is preferred as the upper limit. If the total rolling rate within the temperature range above the final rolling temperature FT in the α region but below _Ar3 temperature does not reach 15%, the processing strain in the α region cannot be sufficiently accumulated in the processed α grains after the phase transformation of the self-processed γ grains, making it difficult to achieve aggregation towards the {411} crystal orientation in the final product. The shrinkage rate within the temperature range above FT and below Ar ₃ is preferably set to 20% or more, and more preferably 25% or more. There is no upper limit specified for the total shrinkage rate; setting it above 40% would result in excessive load on the roll mill, therefore, 40% is preferred as the upper limit. In this embodiment, the shrinkage rate RR0 during hot rolling is defined as follows: Shrinkage rate RR0 (%) = (1 - Plate thickness after rolling within the temperature range during hot rolling / Plate thickness before rolling within the temperature range during hot rolling) × 100

The aforementioned lower limit temperature for the α-zone roller rolling is not specifically limited. If the roller rolling temperature decreases, the load on the roller rolling mill increases. Therefore, it is preferable to set it above 600°C. Furthermore, since the temperature drop caused by roller contact and cooling lubricant competes with the temperature rise caused by the processing process, it is considered that the aforementioned roller rolling temperature may be higher or lower than the specified judgment temperature (Ar ₃ temperature, or Ar ₃ + 20°C) during the processing of the roller rolling pass. In this embodiment, this situation is handled in the following manner. During the rolling process, the temperature on the infeed side is set to TPI (°C) and the plate thickness on the infeed side is set to TCI (mm). The temperature on the outfeed side is set to TPO (°C) and the plate thickness on the outfeed side is set to TCO (mm). Furthermore, it is assumed that the changes in plate thickness and temperature during the rolling process change linearly. That is, it is assumed that when the plate thickness at a specific time point during the rolling process is set to TCa (mm) and the temperature is set to TPa (°C), the following formula always holds true during the rolling process. (TCa－TCO)/(TCI－TCO)＝(TPa－TPO)/(TPI－TPO) Therefore, even if the specified judgment temperature (Ar ₃ temperature, or Ar ₃ + 20℃) is reached during the rolling process, the plate thickness at that point in time can still be determined. That is, the plate thickness TCa (mm) when a specific temperature TPa (℃) is reached midway through the rolling process can be obtained by the following formula: TCa＝TCO＋(TCI－TCO)×(TPa－TPO)/(TPI－TPO).

Here, it should be noted that the aforementioned assumption also presupposes that the exit temperature of the rolling pass is higher than the inlet temperature. That is, even if the steel plate whose inlet temperature TPI of that pass does not reach the Ar ₃ temperature rises in temperature due to the heat generated during processing in that pass, and exits at an outlet temperature TPO above the Ar ₃ temperature, it is determined that rolling in the γ zone (temperature range above Ar ₃ temperature and below Ar ₃ + 20°C) required by this invention was performed in the latter half of that pass. Furthermore, it is also conceivable that temperature variations interspersed with the Ar ₃ temperature can occur in multiple passes. In this case, in this embodiment, the rolling condition in the α zone is defined as "the final rolling process in the α zone". Furthermore, the rolling conditions in zone γ are defined as the rolling process in zone γ before the aforementioned "final rolling process in zone α". That is, when the rolling temperature changes after hot rolling begins in zone γ according to the sequence γ zone (start of hot rolling) ⇒ zone α1 ⇒ zone γ1 ⇒ zone α2 ⇒ zone γ2 ⇒ zone α3 (end of hot rolling), the steel plate of the present invention can be obtained as long as zone α3 and zone γ2 meet the conditions of this embodiment.

The rolling temperature in each pass can be measured, for example, using thermometers installed on the inlet or outlet side of the rolling mill used for the target pass. Furthermore, it is not necessary to install thermometers at all positions on the inlet and outlet sides of the rolling mill within the temperature range of this invention; the rolling temperature at intermediate rolling mills can be calculated based on the actual temperatures of appropriately installed thermometers before and after them. Currently, hot rolling typically uses this calculated temperature for control. Moreover, the final rolling temperature FT is preferably set to below Ar ₃ temperature.

Subsequently, the hot-rolled steel sheet is coiled without undergoing hot-roll annealing. The coiling temperature is preferably above 450°C but below 650°C. By coiling the hot-rolled steel sheet after hot rolling at a temperature above 450°C but below 650°C, the strain introduced by hot rolling in the α-zone is moderately mitigated. This allows for the refinement of the crystalline structure before cold rolling, influencing the recrystallization behavior during intermediate annealing. During the intermediate annealing stage, the development of the {411} crystalline orientation is promoted more than that of the {100} crystalline orientation. It can achieve the effect of enriching the {411} crystal orientation with excellent magnetic properties during expansion. The winding temperature is preferably 500℃～600℃, and even more preferably 520℃～580℃.

(Cold Rolling Step) In the cold rolling step, the hot-rolled steel sheet after the cooling step is cold-rolled to obtain a cold-rolled steel sheet. Specifically, after hot rolling, the hot-rolled steel sheet is pickled and then cold-rolled. During cold rolling, it is preferable to set the shrinkage rate to 80%–92%. Furthermore, a higher shrinkage rate facilitates the growth of grains with the {411} crystalline orientation through subsequent expansion, but this deteriorates the sheet shape and makes operation more difficult.

Furthermore, during cold rolling, it is preferable to perform at least one pass of rolling with a roll ratio of 5.0 or less. By setting the roll ratio to 5.0 or less, additional shear strain is introduced, promoting the formation of the {411} crystal orientation during cold rolling. From this perspective, it is preferable to set it to 4.5 or less, and even more preferably to set it to 4.0 or less. There is no specific lower limit for the roll ratio, but it is difficult to control it below 1.0; therefore, it is preferable to use this as the lower limit. Furthermore, the roll ratio is defined by the following formula (a): Γ＝ld/hm・・・(a) Where, the symbols in the aforementioned formula (a) are defined as follows: Γ: Roller profile ratio ld: Projected contact arc length hm: Average plate thickness

Furthermore, the aforementioned ld and hm are calculated from the following equations (b) and (c): ld＝√(R×(H－h))・・・(b) hm＝(H＋2h)/3・・・(c) However, the symbols in the aforementioned equations (b) and (c) are defined as follows: R: Roll radius H: Infeed plate thickness (thickness of the plate before entering the mill in that pass) h: Outfeed plate thickness (thickness of the plate when leaving the mill in that pass)

(Intermediate Annealing Step) In the intermediate annealing step, the cold-rolled steel sheet undergoes intermediate annealing. In this embodiment, the intermediate annealing temperature is controlled to be below 900°C. Preferably, the intermediate annealing temperature is set below 800°C, and more preferably below 750°C. If the intermediate annealing temperature is above 900°C, excessive grain growth will occur, making it difficult to achieve accumulation towards the {411} crystalline orientation, even with the subsequent temper rolling and final annealing. Furthermore, if the intermediate annealing temperature is too low and sufficient recrystallization is not achieved, the growth of grains with the {411} crystalline orientation will be inhibited even with the subsequent temper rolling and final annealing. Therefore, the intermediate annealing temperature is preferably set to 600°C or higher, and more preferably 700°C or higher. The temperatures described here are based on continuous annealing, and the intermediate annealing time is preferably within the range of 5–120 seconds. This annealing temperature and time range is considered suitable because the {411} grains, which are generated in large quantities before the cold rolling step, grow appropriately through expansion, and are then placed in a state conducive to strain-induced grain growth through the tempering and final annealing processes described later.

(Temperature Rolling Step) In the temperer rolling step, the steel sheet after the aforementioned intermediate annealing step is subjected to temperer rolling. As mentioned above, if temperer rolling and annealing are performed while the {411} crystal orientation is already enriched through expansion, the grains with the {411} crystal orientation will further grow. The reason lies in the following property: by temper rolling, strain does not easily accumulate in grains with the {411} crystalline orientation, but easily accumulates in grains belonging to the {111}<112> or {111}<110> orientation groups, which are called γ-fibers and have the {111} plane orientation. During the subsequent annealing process, grains with less strain and the {411} crystalline orientation will, driven by strain difference, erode these γ-fiber orientation grains. This erode phenomenon driven by strain difference is called strain-induced grain boundary migration (hereinafter referred to as SIBM). The shrinkage rate of the temper rolling is preferably set to 5% and not exceeding 25%. If the shrinkage rate is less than 5%, the strain is too small, and therefore, strain-induced grain boundary migration (hereinafter referred to as SIBM) will not occur during subsequent annealing, and grains with the {411} crystalline orientation will not increase in size. On the other hand, if the shrinkage rate is 25% or more, the strain becomes excessive, resulting in recrystallization nucleation (hereinafter referred to as nucleation), that is, new grains are generated from grains with the γ-fiber orientation. Most of the grains generated in this nucleation are grains with the γ-fiber orientation, thus the magnetic properties deteriorate. From the viewpoint of increasing the average magnetic flux density within the plate surface and reducing anisotropy, the shrinkage rate of the tempered roller is preferably set to 5% to 15%.

Furthermore, when the non-directional electromagnetic steel plate has the strain distribution as described above, it is preferable to adjust the shrinkage rates of the cold rolling and the tempering rolling to make 5 < RR2 < 25 when the shrinkage rate (%) during tempering rolling is set to RR2.

Here, the shrinkage rate RR1 (%) during cold rolling is defined as follows: Shrinkage rate RR1 (%) = (1 - Plate thickness after the final pass of cold rolling / Plate thickness before the first pass of cold rolling) × 100 Furthermore, the shrinkage rate RR2 (%) during temper rolling is defined as follows: Shrinkage rate RR2 (%) = (1 - Plate thickness after the final pass of temper rolling / Plate thickness before the first pass of temper rolling) × 100

(Final Annealing Step) In the final annealing step, the steel sheet after the aforementioned tempered and quenched roll is subjected to final annealing. This final annealing generates SIBM driven by the strain difference in each crystal orientation produced by the tempered and quenched roll. Grains in the {411} crystal orientation, which is the target of this invention, will grow preferentially, and the {411} crystal orientation aggregation of the steel sheet will be improved. Those skilled in this technique can simultaneously monitor the formation of SIBM (Self-Induced Intake) and appropriately set the annealing conditions. For example, for continuous annealing, annealing at 700–950°C for 1–100 seconds can be used; for batch annealing, annealing at 650–850°C for 0.5–2 hours can be used, but there are no particular limitations.

The non-directional electromagnetic steel plate of this embodiment can be manufactured in the manner described above. However, this manufacturing method is one example of a method for manufacturing the non-directional electromagnetic steel plate of this embodiment, and is not a limitation thereof.

The non-directional electromagnetic steel sheet of this embodiment can be manufactured using the above method. Furthermore, the final annealing step can be performed by the steel sheet manufacturer, for example, after tempering and rolling, in the form of a steel coil or a cut sheet. Alternatively, the final annealing step can be omitted after tempering and rolling, and the motor manufacturer can process the steel sheet into a specified shape for the motor core, stack it, and then perform the final annealing in the core shape. In the latter case, it can also be performed as a "relaxation annealing" process normally performed by the motor manufacturer on the motor core. Furthermore, the final annealing can also be performed by both the steel plate manufacturer and the motor manufacturer, in the form of two or more final annealing processes. By adjusting the final annealing after tempering and rolling, the residual strain, grain size, and the degree of development of the {411} orientation can be adjusted. Steel plates with a high residual strain or relatively small grain size have high strength, especially for non-directional electromagnetic steel plates used as rotor cores, which suppress deformation caused by centrifugal force generated with the rotation of the core, thus being superior. On the other hand, steel plates that adequately relieve strain and result in coarse grains are preferable, especially for use as non-directional electromagnetic steel plates in stator cores, as they suppress iron loss.

Steel components made from the non-directional electromagnetic steel plate of this embodiment can be used, for example, in the core of a rotating motor. In this case, flat plates are cut from the non-directional electromagnetic steel plate of this embodiment and these flat plates are appropriately laminated to manufacture the core used in the rotating motor. Because the core uses a non-directional electromagnetic steel plate with excellent magnetic properties, iron losses are suppressed, resulting in a rotating motor with excellent torque. Steel components made from the non-directional electromagnetic steel plate of this embodiment can also be used in products other than the core of a rotating motor, such as the cores of linear motors or stationary mechanisms (reactors or transformers). Implementation Examples

Secondly, embodiments are presented to specifically illustrate the non-directional electromagnetic steel plate of the present invention. The embodiments shown below are merely one example of the non-directional electromagnetic steel plate of the present invention, and the non-directional electromagnetic steel plate of the present invention is not limited to the following examples.

Ingots with the compositions shown in Table 1 are produced by casting molten steel. Furthermore, "Co, etc." in Table 1 indicates the content of Co, Pt, Pb, and Au. The produced ingots are then hot-rolled under the conditions shown in Table 1 to obtain hot-rolled sheets. Next, cold-rolled sheets are obtained under the conditions shown in Table 1.

The aforementioned cold roll sheet was subjected to intermediate annealing for 30 seconds at the temperature shown in Table 2 in an environment without oxidizing gas, and then subjected to a second cold roll (tempering roll) at the shrinkage rate shown in Table 2.

Secondly, to study the aggregate structure, a portion of the steel plate was cut off and thinned to 7/8 of its original thickness. The machined surface (the ground surface after grinding 1/8 of the steel plate from the plate side) was then subjected to EBSD observation (step interval: 0.3 μm) according to the above procedure. Based on the EBSD observation, the area and average KAM value of the oriented grains for the types shown in Table 3 were determined.

Furthermore, as a final annealing process, the steel plate was annealed at 800°C for 2 hours. 55mm square specimens were collected from the steel plate after final annealing as test samples. At this time, specimens with one side parallel to the rolling direction and specimens tilted at 45 degrees relative to the rolling direction were collected. A shearing machine was also used to collect the samples. Next, to study the aggregate structure, a portion of the steel plate was cut off, and the cut specimen was thinned to 7/8 of its thickness. The machined surface (the ground surface after grinding 1/8 of the steel plate from the plate side) was subjected to EBSD observation (step interval: 2.0 μm) according to the above procedure. Using EBSD observation, the area and average KAM value of the oriented grains for the types shown in Table 3 were determined. Furthermore, according to JIS C2556 (2015), the magnetic flux density _B50L in the rolling direction _, the magnetic flux density _B50D at 45° relative to the rolling direction _{, and} the magnetic flux density _B50C at 90° relative to the rolling direction were measured. The measurement results are shown in Table 3. Moreover, the "average value" shown in Table 3 is the circumferential average value of the magnetic flux density _B50 (the average value of the magnetic flux density _B50 in the rolling direction, the direction at 90° relative to the rolling direction, and the direction at 45° (135°) relative to the rolling direction).

Furthermore, the rollability is evaluated as follows: Within a 1m length region centered on the following locations: 10m from the top of the outermost edge of the cold-rolled coil (at the top), 1/2 the length of the coil from the top of the outermost edge (at the middle), and 10m from the bottom of the innermost edge (at the bottom) in the length direction, a total of two or more cracks exceeding 1cm in length appearing on both ends of the coil in the width direction is rated "N". All other conditions are rated "Y". Furthermore, while this embodiment uses cold-rolled steel coils as the evaluation object for rollability, when evaluating steel plates cut from cold-rolled coils, the width-direction end faces can also be observed at three or more different positions along the length (rolling direction) of the steel plate, similar to the aforementioned method. For example, observations can be made within approximately 1/10 of the total length of the steel plate, centered at positions approximately 1/10, 1/2, and 9/10 of the length in the length direction. The total length of the steel plate can be set to 1 meter or more.

[Table 1-1] Chemical composition (the remainder consists of Fe and impurities) Steel C Si sol.Al S N P Mn Cu Ni Mn, Cu, Ni combined [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] A01 0.0018 2.80 0.02 0.002 0.0018 0.010 2.40 1.30 0.70 4.40 A02 0.0052 3.60 0.17 0.004 0.0036 0.020 2.40 0.02 0.01 2.43 A03 0.0089 3.00 0.43 0.005 0.0016 0.010 2.40 0.02 0.02 2.44 A04 0.0043 2.80 0.15 0.004 0.0025 0.030 1.60 0.40 0.30 2.30 A05 0.0018 2.50 0.15 0.007 0.0018 0.010 2.10 0.02 0.01 2.13 A06 0.0011 2.10 0.23 0.004 0.0044 0.040 0.30 1.30 0.70 2.30 A07 0.0036 3.40 0.31 0.003 0.0018 0.010 2.40 0.02 0.02 2.44 A08 0.0023 2.80 0.15 0.004 0.0053 0.120 2.40 0.03 0.01 2.44 A09 0.0032 2.50 0.15 0.004 0.0018 0.020 2.40 0.02 0.03 2.45 A10 0.0061 2.40 0.46 0.002 0.0026 0.010 0.70 0.04 0.02 0.76 A11 0.0018 2.10 0.10 0.004 0.0018 0.030 0.30 0.02 0.03 0.35 A12 0.0023 2.80 0.15 0.001 0.0032 0.010 1.40 0.50 0.30 2.20 A13 0.0044 2.40 0.82 0.004 0.0018 0.010 3.35 0.05 0.01 3.41 A14 0.0022 1.90 0.06 0.002 0.0020 0.080 0.50 0.06 0.01 0.57 A15 0.0026 2.30 0.03 0.003 0.0019 0.020 2.30 0.03 0.02 2.35 A16 0.0021 1.90 0.20 0.003 0.0022 0.010 3.50 0.02 0.01 3.53 A17 0.0025 2.50 0.30 0.007 0.0092 0.010 2.20 0.05 0.03 2.28 A18 0.0021 1.90 0.10 0.002 0.0023 0.350 1.90 0.06 0.03 1.99 A19 0.0018 3.10 0.01 0.05 0.0023 0.009 1.30 0.04 0.03 1.37 A20 0.0026 3.00 0.30 0.008 0.0024 0.010 1.00 0.80 0.50 2.30 A21 0.0025 2.30 0.12 0.007 0.0021 0.010 0.50 0.03 0.02 0.55

[Table 1-2] Steel Co et al. Mn, Cu, Ni, Co, Pt, Pb, Au total Ti Nb Mo Cr Sn Sb Mg, etc. Ar3 [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] [Quality%] ℃ A01 4.40 - 640 A02 2.43 0.0050 Ca: 0.002, Ce: 0.002 866 A03 Co: 0.05 2.49 0.0036 - 862 A04 2.30 0.0050 0.0031 - 878 A05 2.13 0.0042 Mg: 0.005 862 A06 2.30 0.0015 0.1 - 890 A07 Pb: 0.02 2.46 0.0023 0.03 - 867 A08 2.44 0.0036 Ba: 0.002, Zn: 0.002 866 A09 2.45 0.0011 Pr: 0.002 827 A10 0.76 0.0023 1.5 867 A11 0.35 0.0010 Sr: 0.002, Cd: 0.002 1066 A12 2.20 0.0009 2.1 788 A13 3.41 0.0043 758 A14 0.57 0.0023 0.5 La: 0.002, Nd: 0.002 982 A15 2.35 0.0033 0.02 - 823 A16 3.53 0.0019 - 678 A17 Pt: 0.01 2.29 0.0008 857 A18 1.99 0.0015 954 A19 Au: 0.01 1.39 0.0032 963 A20 2.30 0.0013 0.1 906 A21 0.55 0.0010 Sr: 0.002, Cd: 0.002 1043

[Table 2-1] perverted point Hot Roller Steps Cold Roller Steps Intermediate annealing step Tempered roller rolling steps Final annealing step No. Steel Ar3 temperature heating temperature Compressibility of Ar3+20℃ to Ar3℃ The shrinkage rate did not reach the Ar3 to FT. Final rolling temperature (FT) winding temperature Shrinkage rate RR1 Roller shape ratio Annealing temperature T1 Roller shrinkage rate RR2 Annealing temperature T2 [℃] [℃] [%] [%] [℃] [℃] [%] [-] [℃] [%] [℃] 1 A01 640 1150 twenty one 25 610 400 89 4.3 700 10 800 2 A02 866 1150 20 twenty four 835 570 89 4.1 700 10 800 3 A03 862 1150 19 25 830 570 89 4.2 700 10 800 4 A04 878 1150 20 26 850 570 90 4.3 700 10 800 5 A05 862 1150 18 25 830 570 89 4.2 700 10 800 6 A06 890 1150 20 twenty four 865 570 89 4.2 700 10 800 7 A07 867 1150 twenty two 25 835 570 89 4.2 700 10 800 8 A08 866 1150 20 25 835 570 88 4.1 700 10 800 9 A09 827 1150 19 twenty three 800 570 89 4.2 700 10 800 10 A10 867 1150 20 25 835 570 89 4.1 700 10 800 11 A11 1066 1200 twenty one twenty four 1035 570 89 4.2 700 10 800 12 A12 788 1150 20 25 760 570 89 4.2 700 10 800 13 A13 758 1150 twenty one 26 730 570 89 4.3 700 10 800 14 A14 982 1150 20 25 950 570 89 4.2 700 10 800 15 A15 823 1150 20 twenty four 790 570 89 4.2 700 10 800 16 A16 678 1150 twenty two 25 650 450 89 4.2 700 10 800 17 A17 857 1150 18 twenty three 830 550 90 4.2 700 10 800 18 A18 954 1150 twenty one twenty four 920 550 90 4.3 700 10 850 19 A19 963 1150 20 twenty two 890 500 90 4.2 700 10 800 20 A20 906 1150 20 twenty four 870 500 90 4.1 700 10 780 twenty one A21 1043 1200 twenty one twenty four 998 570 89 4.2 700 10 800

[Table 2-2] perverted point Hot Roller Steps Cold Roller Steps Intermediate annealing step Tempered roller rolling steps Final annealing step No. Steel Ar3 temperature heating temperature Compressibility of Ar3+20℃ to Ar3℃ The shrinkage rate did not reach the Ar3 to FT. Final rolling temperature (FT) winding temperature Shrinkage rate RR1 Roller shape ratio Annealing temperature T1 Roller shrinkage rate RR2 Annealing temperature T2 [℃] [℃] [%] [%] [℃] [℃] [%] [-] [℃] [%] [℃] twenty two A02 866 1150 7 27 825 570 90 4.1 700 12 800 twenty three A02 866 1150 19 25 830 570 75 4.1 700 12 800 twenty four A02 866 1150 25 17 830 570 90 4.1 700 12 800 25 A02 866 1150 twenty one 10 835 570 90 4.1 700 12 800 26 A02 866 1150 20 25 835 400 90 4.1 700 12 800 27 A02 866 1150 19 26 830 680 90 4.1 700 12 800 28 A02 866 1150 20 twenty four 830 570 90 4.1 700 3 800 29 A02 866 1150 twenty one 25 830 570 90 4.1 550 7 800 30 A02 866 1150 20 26 830 570 90 4.1 700 30 800 31 A15 823 1150 14 30 790 570 90 4.2 700 12 800 32 A15 823 1150 19 25 790 570 90 4.2 1000 12 800 33 A15 823 1150 20 twenty four 790 570 90 8.9 700 12 800 34 A15 823 1150 20 twenty three 790 550 82 4.2 700 10 800 35 A15 823 1100 20 28 730 500 90 4.1 700 10 850 36 A15 823 1150 twenty three 25 780 570 95 4.9 700 10 800 37 A15 823 1150 11 15 800 600 85 4.3 680 0 800 38 A15 823 1150 20 25 790 500 89 4.3 700 twenty three 800

[Table 3-1] No. Observation results of EBSD after heat treatment and rolling EBSD observation results after annealing at 800℃ for 2 hours Magnetic properties after annealing at 800℃ for 2 hours Roller properties Remarks S ₄₁₁ /S _{100 Styl} / St _tot S ₄₁₁ /S _tot S ₄₁₁ /S _tra K ₄₁₁ /K _tyl S ₄₁₁ /S _{100 Styl} / St _tot S ₄₁₁ /S _tot S ₄₁₁ /S _tra B50L B50D B50C average value Left side of formula (A) [-] [-] [-] [-] [-] [-] [-] [-] [-] [T] [T] [T] [T] [T] 1 0.91 0.72 0.14 0.49 0.980 1.67 0.36 0.27 0.42 1.520 1.772 1.490 1.639 0.267 N Comparative example 2 1.82 0.56 0.32 0.73 0.979 3.40 0.11 0.76 0.86 1.601 1.735 1.556 1.657 0.156 Y Invention Example 3 1.78 0.58 0.30 0.71 0.979 3.93 0.06 0.81 0.84 1.605 1.761 1.571 1.674 0.174 Y Invention Example 4 2.13 0.65 0.24 0.69 0.984 4.00 0.07 0.83 0.90 1.641 1.776 1.615 1.702 0.147 Y Invention Example 5 1.56 0.69 0.21 0.67 0.978 3.10 0.06 0.75 0.80 1.606 1.758 1.571 1.673 0.170 Y Invention Example 6 1.67 0.63 0.25 0.67 0.982 3.54 0.04 0.79 0.82 1.628 1.740 1.592 1.675 0.130 Y Invention Example 7 2.01 0.54 0.33 0.72 0.980 4.08 0.12 0.73 0.83 1.605 1.755 1.575 1.672 0.165 Y Invention Example 8 1.89 0.60 0.27 0.66 0.980 4.25 0.04 0.85 0.89 1.592 1.762 1.566 1.671 0.183 Y Invention Example 9 1.92 0.44 0.42 0.75 0.979 4.08 0.11 0.79 0.88 1.602 1.763 1.571 1.675 0.177 Y Invention Example 10 1.73 0.56 0.32 0.73 0.983 3.02 0.10 0.74 0.82 1.621 1.777 1.577 1.688 0.178 Y Invention Example 11 0.97 0.92 0.02 0.25 0.978 1.23 0.32 0.25 0.37 1.540 1.692 1.512 1.609 0.166 Y Comparative example 12 1.69 0.73 0.18 0.68 0.980 2.42 0.12 0.63 0.72 1.635 1.745 1.591 1.679 0.132 Y Invention Example 13 1.01 0.83 0.10 0.59 0.987 1.98 0.10 0.63 0.70 1.550 1.755 1.544 1.651 0.208 N Comparative example 14 1.87 0.59 0.28 0.68 0.985 3.54 0.07 0.81 0.87 1.596 1.768 1.555 1.672 0.193 Y Invention Example 15 1.92 0.55 0.32 0.70 0.980 3.66 0.11 0.74 0.83 1.628 1.773 1.584 1.690 0.167 Y Invention Example 16 0.98 0.82 0.02 0.11 0.980 1.76 0.54 0.28 0.61 1.549 1.726 1.502 1.626 0.201 N Comparative example 17 1.67 0.75 0.16 0.64 0.979 3.10 0.41 0.36 0.61 1.592 1.735 1.559 1.655 0.160 Y Invention Example 18 1.02 0.68 0.26 0.81 0.980 3.58 0.05 0.73 0.77 1.608 1.739 1.547 1.658 0.162 Y Invention Example 19 1.59 0.65 0.33 0.94 0.978 3.26 0.15 0.75 0.88 1.620 1.735 1.552 1.661 0.149 Y Invention Example 20 1.53 0.59 0.38 0.93 0.980 2.10 0.21 0.67 0.85 1.592 1.738 1.592 1.665 0.146 Y Invention Example twenty one 1.08 0.83 0.18 1.06 0.980 2.15 0.33 0.42 0.63 1.588 1.721 1.579 1.652 0.138 Y Invention Example

[Table 3-2] No. Observation results of EBSD after heat treatment and rolling EBSD observation results after annealing at 800℃ for 2 hours Magnetic properties after annealing at 800℃ for 2 hours Roller properties Remarks S ₄₁₁ /S _{100 Styl} / St _tot S ₄₁₁ /S _tot S ₄₁₁ /S _tra K ₄₁₁ /K _tyl S ₄₁₁ /S _{100 Styl} / St _tot S ₄₁₁ /S _tot S ₄₁₁ /S _tra B50L B50D B50C average value Left side of formula (A) [-] [-] [-] [-] [-] [-] [-] [-] [-] [T] [T] [T] [T] [T] twenty two 0.89 0.72 0.15 0.53 0.989 1.60 0.27 0.46 0.63 1.550 1.736 1.509 1.633 0.207 Y Comparative example twenty three 1.01 0.16 0.45 0.53 0.979 1.02 0.52 0.25 0.52 1.553 1.592 1.585 1.581 0.023 Y Comparative example twenty four 1.75 0.49 0.36 0.70 0.979 2.90 0.19 0.62 0.77 1.589 1.732 1.555 1.652 0.160 Y Invention Example 25 0.92 0.69 0.18 0.57 0.979 1.58 0.12 0.76 0.86 1.555 1.750 1.508 1.641 0.219 Y Comparative example 26 0.76 0.69 0.17 0.52 0.991 1.27 0.29 0.61 0.86 1.577 1.733 1.515 1.640 0.187 Y Comparative example 27 0.82 0.55 0.21 0.47 0.990 1.34 0.13 0.75 0.86 1.589 1.752 1.502 1.649 0.207 Y Comparative example 28 1.51 0.62 0.23 0.60 1.030 2.79 0.55 0.29 0.64 1.525 1.588 1.555 1.564 0.048 Y Comparative example 29 1.82 0.89 0.17 1.57 0.979 1.72 0.38 0.18 0.29 1.553 1.592 1.586 1.581 0.023 Y Comparative example 30 0.96 0.73 0.38 1.40 1.013 1.83 0.11 0.23 0.26 1.580 1.620 1.550 1.593 0.055 Y Comparative example 31 1.92 0.58 0.30 0.70 0.980 3.26 0.07 0.76 0.82 1.592 1.758 1.552 1.665 0.186 Y Invention Example 32 0.89 0.66 0.02 0.06 1.001 1.24 0.14 0.71 0.83 1.562 1.623 1.562 1.593 0.061 Y Comparative example 33 0.92 0.51 0.26 0.53 0.989 1.97 0.11 0.49 0.55 1.589 1.750 1.503 1.648 0.204 Y Comparative example 34 1.12 0.22 0.57 0.73 0.980 2.01 0.27 0.45 0.06 1.582 1.723 1.572 1.650 0.146 Y Invention Example 35 1.01 0.20 0.77 0.96 0.970 3.36 0.15 0.44 0.52 1.593 1.725 1.505 1.637 0.176 Y Invention Example 36 2.30 0.21 0.83 1.04 0.978 1.95 0.42 0.31 0.53 1.572 1.605 1.598 1.595 0.020 Y Comparative example 37 1.15 0.52 0.36 0.75 0.980 2.02 0.58 0.31 0.74 1.590 1.695 1.610 1.648 0.095 Y Comparative example 38 2.02 0.49 0.33 0.65 0.986 2.11 0.15 0.55 0.65 1.605 1.709 1.592 1.654 0.111 Y Invention Example

Furthermore, for steel plate No. 12, the sample was thinned to half its original thickness, and EBSD observation was performed on its machined surface according to the above-mentioned procedures. The area of the oriented grains and the average KAM value for the types shown in Table 4 were determined. The results, magnetic properties, and rollability are presented together in Table 4.

[Table 4] No. Measurement location Observation results of EBSD after heat treatment and rolling EBSD observation results after annealing at 800℃ for 2 hours Magnetic properties after annealing at 800℃ for 2 hours Roller properties Remarks S ₄₁₁ /S _{100 Styl} / St _tot S ₄₁₁ /S _tot S ₄₁₁ /S _tra K ₄₁₁ /K _tyl S ₄₁₁ /S _{100 Styl} / St _tot S ₄₁₁ /S _tot S ₄₁₁ /S _tra B50L B50D B50C average value Left side of formula (A) [-] [-] [-] [-] [-] [-] [-] [-] [-] [T] [T] [T] [T] [T] 12 7/8 thick 1.69 0.73 0.18 0.68 0.980 2.42 0.12 0.63 0.72 1.635 1.745 1.591 1.679 0.132 Y Invention Example 1/2 thick 1.73 0.73 0.17 0.63 0.992 2.40 0.13 0.64 0.74 [Industry-level applicability]

According to the present invention, an omnidirectional electromagnetic steel plate with small in-plane anisotropy and excellent circumferential (all-directional) average magnetic properties can be provided, which is of great industrial use.

Furthermore, the entire invention of Japanese Patent Application No. 2023-001935 is incorporated herein by reference. All documents, patent applications, and technical standards described in this specification are incorporated herein by reference to the same extent as in cases where each document, patent application, and technical standard is incorporated herein by reference individually and independently.

(without)

Claims (4)

A non-directional electromagnetic steel plate has the following chemical composition: by mass percentage, it contains C: less than 0.0100%, Si: 1.50% to 4.00%, sol.Al: 0.0001% to 1.0%, S: less than 0.0100%, N: less than 0.0100%, Mn: more than 0.10%, one or more of Mn, Ni, and Cu selected: total not exceeding 2.50%, Mo: 0.0% to less than 2.5%, Cr: 0.0% to less than 2.5%, Ti: 0.000% to 0.005%, Nb: 0.000% to 0.005%, Sn: 0.000% to 0.400%, Sb: 0.000% to 0.400%. P: 0.000%～0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%～0.0100%, with C content (in mass%) set as [C], Mo content as [Mo], Cr content as [Cr], Mn content as [Mn], Ni content as [Ni], Cu content as [Cu], Si content as [Si], sol.Al content as [sol.Al], and P content as [P]. In this case, the metamorphic temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C, and the remainder consists of Fe and impurities. Furthermore, when using EBSD to observe the ground surface parallel to the steel plate surface and after grinding 1/8 of the steel plate side, the total area is set as S _tot , the area of the {411} oriented grains is set as S ₄₁₁ , the area of the {100} oriented grains is set as S ₁₀₀ , the area of the oriented grains with a Taylor factor M exceeding 2.9 according to the following formula (2) is set as S _tyl , the total area of the aforementioned oriented grains with a Taylor factor M less than 2.9 is set as S _tra , the average KAM value of the {411} oriented grains is set as K ₄₁₁ , and the average KAM value of the aforementioned oriented grains with a Taylor factor M exceeding 2.9 is set as K _tyl . In this case, the following formulas (3) and (4) to (7) are satisfied; Ar ₃ (℃)＝1020-325×[C]+33×[Si]+287×[P]+80×[sol.Al]-120×([Mn]+[Mo]+[Cu])-46×([Cr]+[Ni])・・・(1) M＝(cosϕ×cosλ) ^-1・・・(2) S ₄₁₁ /S ₁₀₀ ＞1.00・・・(3) 0.20≦S _tyl /S _tot ≦0.85・・・(4) 0.05≦S ₄₁₁ /S _tot ≦0.80・・・(5) S ₄₁₁ /S _tra ≧0.50・・・(6) K ₄₁₁ /K _tyl ≦0.990・・・(7) Here, in equation (2), ϕ represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal. A non-directional electromagnetic steel plate has the following chemical composition (by mass%): C: less than 0.0100%, Si: 1.50%–4.00%, sol.Al: 0.0001%–1.0%, S: less than 0.0100%, N: less than 0.0100%, Mn: more than 0.10%, one or more of Mn, Ni, Co, Pt, Pb, Au, and Cu: total not exceeding 2.50%, Mo: 0.0%–not exceeding 2.5%, Cr: 0.0%–not exceeding 2.5%, Ti: 0.000%–0.005%, Nb: 0.000%–0.005%, Sn: 0.000%–0.400%, Sb: 0.000%–0.400%. P: 0.000%～0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%～0.0100%, with C content (in mass%) set as [C], Mo content as [Mo], Cr content as [Cr], Mn content as [Mn], Ni content as [Ni], Cu content as [Cu], Si content as [Si], sol.Al content as [sol.Al], and P content as [P]. In this case, the metamorphic temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C, and the remainder consists of Fe and impurities. Furthermore, when using EBSD to observe the ground surface parallel to the steel plate surface and after grinding 1/8 of the steel plate side, the total area is set as S _tot , the area of the {411} oriented grains is set as S ₄₁₁ , the area of the {100} oriented grains is set as S ₁₀₀ , the area of the oriented grains with a Taylor factor M exceeding 2.9 according to the following formula (2) is set as S _tyl , the total area of the aforementioned oriented grains with a Taylor factor M less than 2.9 is set as S _tra , the average KAM value of the {411} oriented grains is set as K ₄₁₁ , and the average KAM value of the aforementioned oriented grains with a Taylor factor M exceeding 2.9 is set as K _tyl . In this case, the following formulas (3) and (4) to (7) are satisfied; Ar ₃ (℃)＝1020-325×[C]+33×[Si]+287×[P]+80×[sol.Al]-120×([Mn]+[Mo]+[Cu])-46×([Cr]+[Ni])・・・(1) M＝(cosϕ×cosλ) ^-1・・・(2) S ₄₁₁ /S ₁₀₀ ＞1.00・・・(3) 0.20≦S _tyl /S _tot ≦0.85・・・(4) 0.05≦S ₄₁₁ /S _tot ≦0.80・・・(5) S ₄₁₁ /S _tra ≧0.50・・・(6) K ₄₁₁ /K _tyl ≦0.990・・・(7) Here, in equation (2), ϕ represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal. A non-directional electromagnetic steel plate has the following chemical composition: by mass percentage, it contains C: less than 0.0100%, Si: 1.50% to 4.00%, sol.Al: 0.0001% to 1.0%, S: less than 0.0100%, N: less than 0.0100%, Mn: more than 0.10%, one or more of Mn, Ni, and Cu selected: total not exceeding 2.50%, Mo: 0.0% to less than 2.5%, Cr: 0.0% to less than 2.5%, Ti: 0.000% to 0.005%, Nb: 0.000% to 0.005%, Sn: 0.000% to 0.400%, Sb: 0.000% to 0.400%. P: 0.000%～0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%～0.0100%, with C content (in mass%) set as [C], Mo content as [Mo], Cr content as [Cr], Mn content as [Mn], Ni content as [Ni], Cu content as [Cu], Si content as [Si], sol.Al content as [sol.Al], and P content as [P]. In this case, the metamorphic temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C, and the remainder consists of Fe and impurities. Furthermore, when using EBSD to observe the ground surface parallel to the steel plate surface and after grinding 1/8 of the steel plate side, the total area is set as S _tot , the area of the {411} oriented grains is set as S ₄₁₁ , the area of the {100} oriented grains is set as S ₁₀₀ , the area of the oriented grains with a Taylor factor M exceeding 2.9 according to the following formula (2) is set as S _tyl , and the total area of the aforementioned oriented grains with a Taylor factor M of less than 2.9 is set as S _tra . In this case, the following formulas (8) to (11) are satisfied; Ar ₃ (℃)＝1020－325×[C]＋33×[Si]＋287×[P]＋80×[sol.Al]－120×([Mn]＋[Mo]＋[Cu])－46×([Cr]＋[Ni])・・・(1) M＝(cosϕ×cosλ) ^-1・・・(2) S ₄₁₁ /S ₁₀₀ ＞2.00・・・(8) S _tyl /S _tot ＜0.55・・・(9) S ₄₁₁ /S _tot ＞0.30・・・(10) S ₄₁₁ /S _tra ≧0.60・・・(11) Here, in formula (2), ϕ represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal. A non-directional electromagnetic steel plate has the following chemical composition (by mass%): C: less than 0.0100%, Si: 1.50%–4.00%, sol.Al: 0.0001%–1.0%, S: less than 0.0100%, N: less than 0.0100%, Mn: more than 0.10%, one or more of Mn, Ni, Co, Pt, Pb, Au, and Cu: total not exceeding 2.50%, Mo: 0.0%–not exceeding 2.5%, Cr: 0.0%–not exceeding 2.5%, Ti: 0.000%–0.005%, Nb: 0.000%–0.005%, Sn: 0.000%–0.400%, Sb: 0.000%–0.400%. P: 0.000%～0.400%, and selected from one or more of the group consisting of Mg, Ca, Sr, Ba, Ce, La, Nd, Pr, Zn, and Cd: totaling 0.0000%～0.0100%, with C content (in mass%) set as [C], Mo content as [Mo], Cr content as [Cr], Mn content as [Mn], Ni content as [Ni], Cu content as [Cu], Si content as [Si], sol.Al content as [sol.Al], and P content as [P]. In this case, the metamorphic temperature Ar ₃ (°C) specified by the following formula (1) is 750～1050°C, and the remainder consists of Fe and impurities. Furthermore, when using EBSD to observe the ground surface parallel to the steel plate surface and after grinding 1/8 of the steel plate side, the total area is set as S _tot , the area of the {411} oriented grains is set as S ₄₁₁ , the area of the {100} oriented grains is set as S ₁₀₀ , the area of the oriented grains with a Taylor factor M exceeding 2.9 according to the following formula (2) is set as S _tyl , and the total area of the aforementioned oriented grains with a Taylor factor M of less than 2.9 is set as S _tra . In this case, the following formulas (8) to (11) are satisfied; Ar ₃ (℃)＝1020－325×[C]＋33×[Si]＋287×[P]＋80×[sol.Al]－120×([Mn]＋[Mo]＋[Cu])－46×([Cr]＋[Ni])・・・(1) M＝(cosϕ×cosλ) ^-1・・・(2) S ₄₁₁ /S ₁₀₀ ＞2.00・・・(8) S _tyl /S _tot ＜0.55・・・(9) S ₄₁₁ /S _tot ＞0.30・・・(10) S ₄₁₁ /S _tra ≧0.60・・・(11) Here, in formula (2), ϕ represents the angle between the stress vector and the sliding direction vector of the crystal, and λ represents the angle between the stress vector and the normal vector of the sliding surface of the crystal.