CN116004961A - Preparation method of oriented silicon steel and oriented silicon steel - Google Patents

Abstract

The present application provides a preparation method of grain-oriented silicon steel and grain-oriented silicon steel. The preparation method of grain-oriented silicon steel provided by the present application includes: performing continuous casting on molten steel to obtain a slab; wherein, in terms of mass percentage, the components of the slab include: C: 0.03‑0.09%, Si: 2.8‑ 4.4%; Als: 0.015‑0.030%, N: 0.0050‑0.0095%, Mn: 0.1‑0.4%, Sb: 0.01‑0.05%, Cu: 0.05‑0.25%, S: 0.01‑0.03%, Ni: 0.05‑0.2 %, the rest is Fe and unavoidable impurities; the slab is subjected to hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching and leveling annealing to obtain oriented silicon steel. This application optimizes the chemical composition of the steel, adopts a compound inhibitor system, and uses different main inhibitors in different annealing stages, while eliminating normalization, it ensures good magnetic properties, simplifies the process, and reduces equipment investment And reduce the production cost.

Description

Preparation method of grain-oriented silicon steel and grain-oriented silicon steel

technical field

The present application relates to the technical field of steel preparation, in particular to a method for preparing oriented silicon steel and oriented silicon steel.

Background technique

Oriented silicon steel is an important soft magnetic functional material, mainly used as various transformer cores. It is characterized by excellent magnetic properties in the rolling direction, which is obtained through secondary recrystallization: that is, the growth of normal grains is inhibited by grain growth inhibitors, making certain special orientations The grains engulf the normal grains and abnormal growth occurs.

The production method of grain-oriented silicon steel can be divided into congenital type and acquired type according to the way of obtaining the inhibitor. Congenital inhibitor oriented silicon steel requires high hot rolling heating temperature due to the need to fully dissolve the coarse precipitate particles precipitated in the slab, which brings problems of high energy consumption, low efficiency, and frequent maintenance of the heating furnace. Acquired inhibitor-oriented silicon steel can be supplemented with inhibitors through post-processing, so it can adopt lower heating temperature for hot rolling, and the production cost is greatly reduced. It has become the mainstream production method of grain-oriented silicon steel.

However, the existing technologies of acquired inhibitor type high magnetic induction grain-oriented silicon steel basically need normalization. Normalization will bring three problems: 1) Increased equipment investment; 2) Complicated process flow; 3) Increased production cost.

Contents of the invention

The embodiment of the present application provides a method for preparing oriented silicon steel and oriented silicon steel, aiming to prepare oriented silicon steel through a normalization-free method to reduce costs, increase efficiency, save energy and reduce emissions.

In the first aspect, the embodiment of the present application provides a method for preparing grain-oriented silicon steel, comprising: performing continuous casting on molten steel to obtain a cast slab; the cast slab includes the following components in mass percentage: C: 0.03-0.09% , Si: 2.8-4.4%; Als: 0.015-0.030%, N: 0.0050-0.0095%, Mn: 0.1-0.4%, Sb: 0.01-0.05%, Cu: 0.05-0.25%, S: 0.01-0.03%, Ni: 0.05-0.2%, the rest is Fe and unavoidable impurities; the oriented silicon steel is obtained by hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing.

According to the embodiment of the first aspect of the present application, in the step of obtaining the cast slab, the equiaxed crystal ratio in the cast slab is 20%-60%.

According to the embodiment of the first aspect of the present application, the hot rolling treatment includes: heating the continuous casting slab to 1150°C-1280°C for hot rolling, and controlling the finishing temperature of the hot rolling to 890°C-970°C to obtain a hot-rolled steel plate.

According to an embodiment of the first aspect of the present application, the cold rolling treatment includes: performing primary cold rolling or secondary cold rolling with intermediate annealing on the hot-rolled steel sheet to obtain a cold-rolled steel sheet, and the reduction ratio of the cold rolling treatment is ≥70%.

According to the embodiment of the first aspect of the present application, when the decarburization and nitriding annealing treatment is performed, the decarburization temperature satisfies 790°C to 900°C.

According to the embodiment of the first aspect of the present application, during the decarburization and nitriding annealing treatment, the heating rate v in the temperature range of 500°C-750°C satisfies 40-70°C/s.

According to the embodiment of the first aspect of the present application, the decarburization and nitriding annealing treatment includes: performing continuous decarburization and nitriding annealing on the steel strip in an atmosphere of H ₂ +N ₂ +NH ₃ , and the temperature of nitriding satisfies 800-950°C, The range of the nitriding amount b satisfies 150ppm-300ppm.

According to the embodiment of the first aspect of the present application, the step of obtaining the grain-oriented silicon steel further includes: after decarburization and nitriding annealing, coating the surface of the steel with MgO, drying and performing high-temperature annealing.

In the second aspect, the present application provides a grain-oriented silicon steel prepared by the aforementioned method, including the following components in mass percentage: C: 0.03-0.09%, Si: 2.8-4.4%; Als: 0.015-0.030%, N: 0.0050-0.0095%, Mn: 0.1-0.4%, Sb: 0.01-0.05%, Cu: 0.05-0.25%, S: 0.01-0.03%, Ni: 0.05-0.2%, and the rest are Fe and unavoidable impurities.

According to the embodiment of the second aspect of the present application, the value range of the magnetic induction B ₈ satisfies B ₈ ≥ 1.89T, and the value range of the iron loss P _17/50 satisfies P _17/50 ≤ 1.05W/kg.

Compared with the prior art, the present invention has at least the following beneficial effects:

This application provides a method for preparing grain-oriented silicon steel. By optimizing the chemical composition of the steel, a composite inhibitor system is adopted, and different main inhibitors are used in different annealing stages. While eliminating normalization, good Magnetic properties. The process is simplified, the equipment investment is reduced and the production cost is reduced.

Specifically, Al and N are added to the composition as inhibitor formation elements to form AlN precipitates, which mainly inhibit the normal growth of primary grains before the secondary recrystallization begins, and the Als content is lower than 0.015% or N If the content is lower than 0.005%, the amount of effective inhibitor finally formed is not enough, and the inhibitor strength needed to complete the secondary recrystallization cannot be obtained; if the Als content is higher than 0.030% or the N content is lower than 0.0095%, the solubility of Als and N If the accumulation is too large, it is difficult to completely dissolve the coarse AlN in the slab during hot rolling and heating, and finally the amount of AlN as an effective inhibitor is not enough.

Sb is added to the composition as a grain boundary segregation element to act as an auxiliary inhibitor. The Sb content below 0.01% cannot achieve the effect of the auxiliary inhibitor, and the Sb content exceeding 0.05% will cause serious deterioration of the surface quality.

Cu and S are added to the composition to form CuxS, as the main inhibitor in the primary recrystallization process, if Cu is less than 0.05% or S is less than 0.01%, the amount of inhibitor is too small, Cu is higher than 0.26% or S is higher than 0.03%, the required hot rolling heating temperature is too high, making production difficult.

Adding appropriate Ni to the composition is mainly to improve the uniformity of the primary recrystallized structure.

Detailed ways

Embodiments of the present application will be further described in detail below in conjunction with examples. The detailed description of the following embodiments is used to illustrate the principle of the application, but not to limit the scope of the application, that is, the application is not limited to the described embodiments.

In the description of this application, it should be noted that, unless otherwise specified, the meaning of "plurality" is more than two; the terms "upper", "lower", "left", "right", "inner", " The orientation or positional relationship indicated by "outside" and so on are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a reference to this application. Application Restrictions. In addition, the terms "first", "second", etc. are used for descriptive purposes only, and should not be construed as indicating or implying relative importance. "Perpendicular" does not require verticality in the strict sense, but may include allowable errors. "Parallel" does not require parallelism in the strict sense, but may include allowable errors.

The traditional production process route of acquired inhibitor oriented silicon steel is steelmaking-hot rolling-normalized pickling-cold rolling-decarburization and nitriding coating with magnesium oxide-high temperature annealing-coating and stretch tempering annealing. Annealing of hot-rolled sheet, that is, normalization, is a key process in the production of high magnetic induction oriented silicon steel. The normalization effect is different for congenital and acquired oriented silicon steel. For the congenital grain-oriented silicon steel, normalization is the final and most critical process to determine the form and quantity of the inhibitor; for the acquired type, the function of normalization is to improve the structure and form part of the inhibitor, and the final determination of the inhibitor is During decarburization and nitriding and high temperature annealing.

Acquired inhibitor high magnetic induction oriented silicon steel existing technologies basically require normalization, which will increase equipment investment and production costs, and replacing normalization by high temperature coiling will lead to unstable performance of the finished product due to insufficient suppression ability.

In view of this, the embodiment of the present application provides a preparation method of grain-oriented silicon steel and grain-oriented silicon steel. The preparation method provided in the embodiment of the present application adopts a composite inhibitor system, and different main inhibitors are used in different annealing stages. At the same time, it ensures good magnetic properties, simplifies the process, reduces equipment investment and reduces production costs.

Preparation method of grain oriented silicon steel

In the first aspect, the embodiment of the present application provides a method for preparing grain-oriented silicon steel, comprising: performing continuous casting on molten steel to obtain a cast slab; the cast slab includes the following components in mass percentage: C: 0.03-0.09% , Si: 2.8-4.4%; Als: 0.015-0.030%, N: 0.0050-0.0095%, Mn: 0.1-0.4%, Sb: 0.01-0.05%, Cu: 0.05-0.25%, S: 0.01-0.03%, Ni: 0.05-0.2%, the rest is Fe and unavoidable impurities; the oriented silicon steel is obtained by hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing.

Oriented silicon steel obtains good magnetic properties through secondary recrystallization, and the occurrence of secondary recrystallization depends on two conditions: 1) the grain size of primary recrystallization; 2) the size and distribution of inhibitors. The primary recrystallization is completed during the decarburization annealing process. In order to obtain a suitable primary recrystallization grain size, a certain size and quantity of primary recrystallization inhibitors must be present before decarburization annealing. Therefore, the traditional acquired inhibitor type low temperature AlN is used as the primary recrystallization inhibitor for high magnetic induction oriented silicon steel. In order to make AlN fine and dispersed, it must undergo normalization treatment before primary cold rolling. In order to obtain stronger inhibitory ability before secondary recrystallization, it must be re Nitriding is required. In the examples of this application, by optimizing the chemical composition of the steel, Cu _x S + grain boundary segregation elements are used as the main inhibitor to control the primary recrystallized grain size during the decarburization annealing process, and then obtained by nitriding during the high temperature annealing process. (SiAl)N acts as the main inhibitor to hinder the normal growth of ordinary grains, causing abnormal growth of Gaussian grains and completing secondary recrystallization, which can save the normalization process and obtain high magnetic induction grain-oriented silicon steel.

Specifically, Cu and S are added to the composition to form CuxS, as the main inhibitor in the primary recrystallization process, Cu is lower than 0.05% or S is lower than 0.01%, the amount of inhibitor is too small, Cu is higher than 0.26% or If S is higher than 0.03%, the required hot rolling heating temperature is too high, making production difficult.

Adding appropriate Ni to the composition is mainly to improve the uniformity of the primary recrystallized structure.

Sb is added to the composition as a grain boundary segregation element to act as an auxiliary inhibitor. The Sb content below 0.01% cannot achieve the effect of the auxiliary inhibitor, and the Sb content exceeding 0.05% will cause serious deterioration of the surface quality.

Al and N are added to the composition as inhibitors to form elements to form AlN precipitates, which mainly inhibit the normal growth of primary grains before the secondary recrystallization begins, and the Als content is lower than 0.015% or the N content is lower than 0.005%, the amount of effective inhibitor finally formed is not enough, and the inhibitor strength required to complete the secondary recrystallization cannot be obtained; the Als content is higher than 0.030% or the N content is higher than 0.0095%, and the solubility product of Als and N is too large , leading to the difficulty of complete solid solution of coarse AlN in the slab during hot rolling and heating, and finally the amount of AlN as an effective inhibitor is not enough.

Stretching and leveling annealing after coating the insulating layer can form a sintered insulating coating on the surface of the steel strip, providing insulating properties for the grain-oriented silicon steel, so as to reduce the eddy current loss of the grain-oriented silicon steel during later use.

In some embodiments, after the stretch-levelling annealing treatment, a treatment step of laser scoring is also included, and the laser scoring can further reduce the iron loss of the grain-oriented silicon steel and improve the quality of the grain-oriented silicon steel.

The preparation method of grain-oriented silicon steel provided by this application adopts a composite inhibitor system by optimizing the chemical composition of the steel, and uses different main inhibitors in different annealing stages to ensure good magnetic properties while eliminating normalization , simplifies the process, can reduce equipment investment and reduce production costs.

In some embodiments, in the step of obtaining the cast slab, the range of the mid-axis grain ratio of the cast slab is 20%-60%.

By controlling the cooling intensity and electromagnetic stirring parameters during the continuous casting process, the equiaxed crystal ratio of the slab is controlled below 60% by controlling the continuous casting process, so as to prevent the formation of a large number of coarse precipitates and provide sufficient solid solution for the precipitates during hot rolling and heating. Lay the groundwork.

In some embodiments, the hot rolling treatment includes: heating the continuous casting slab to 1150°C-1280°C for hot rolling, and controlling the finishing temperature of the hot rolling to 890°C-970°C to obtain a hot-rolled steel plate.

In the hot rolling process of the cast slab, it is necessary to control the heating and rolling process temperature to control the solid solution and precipitation of the inhibitor. If the heating temperature is lower than 1150°C, it is difficult to fully dissolve the coarse precipitates in the slab. If the heating temperature is higher than 1280°C, the slag accumulation in the heating furnace will be serious, the quality of the edge of the slab will deteriorate, the energy consumption will increase, and the burning loss will increase. If the finishing temperature of hot rolling is lower than 890°C, a large amount of coarse AlN and _CuxS will be precipitated before the finish rolling, resulting in a serious shortage of effective inhibitory amount. It is easy to cause an increase in rolling failure rate. Hot rolling within the above temperature range can obtain a final product that meets the requirements of excellent performance quality.

In some embodiments, in the step of obtaining the cold-rolled steel sheet, the reduction ratio a of the cold rolling satisfies a≥70%.

According to the embodiment of the present application, when the cold rolling reduction is higher than 70%, for example, the reduction is 75%, 78%, 80%, 82% and 85%. According to the embodiment of the present application, setting the reduction rate to 75% to 85% is beneficial to obtain accurate Gaussian orientation, and the Gaussian texture is the root cause of the excellent magnetic properties of silicon steel, and at the same time, it is beneficial to improve the uniformity of grains and reduce the iron loss of finished steel products.

In some embodiments, when the decarburization and nitriding annealing treatment is performed, the decarburization temperature satisfies 790°C to 900°C.

If the decarburization temperature is lower than 790°C, the diffusion rate of C will decrease, making decarburization difficult. If the decarburization temperature is higher than 900°C, the primary grains will grow and coarsen, which will easily lead to poor secondary recrystallization.

In some embodiments, when the continuous decarburization and nitriding annealing is performed, the heating rate v in the temperature range of 500-750° C. ranges from 40° C./s to 70° C./s.

Decarburization and nitriding annealing adopts rapid heating, rapid heating below the Curie temperature, and controls the heating temperature above 40°C/s to prevent excessive release of cold rolling storage energy before recrystallization begins, and has a large nucleation rate during recrystallization , so as to obtain a fine and uniform primary recrystallized structure.

In some embodiments, the decarburization and nitriding treatment includes: performing continuous nitriding annealing on the steel strip in an atmosphere of H ₂ +N ₂ +NH ₃ , the temperature of nitriding satisfies the range of 800°C-950°C, and the amount of nitriding b is in the range Meet 150ppm-300ppm.

After nitriding treatment, it is easy to form secondary recrystallization inhibitors. Nitriding temperature lower than 800°C will lead to low nitriding efficiency, and nitriding temperature higher than 950°C will lead to primary grain growth and coarsening. Control the amount of nitriding in the range of 150-300ppm, the inhibition ability is insufficient below 150ppm, the secondary recrystallization is unstable above 300ppm, and the bottom layer defects increase.

In some embodiments, after nitriding and annealing, coating MgO on the surface of the silicon steel and performing high temperature annealing after drying.

Coating MgO can act as an isolating agent to prevent strip steel from sticking during high-temperature annealing, and at the same time remove impurities such as nitrogen and sulfur in the steel, and also react with silicon dioxide on the surface of silicon steel to form excellent magnesium silicate insulation bottom layer.

In the second aspect, the present application provides a grain-oriented silicon steel prepared by the aforementioned method, including the following components in mass percentage: C: 0.03-0.09%, Si: 2.8-4.4%; Als: 0.015-0.030%, N: 0.0050-0.0095%, Mn: 0.1-0.4%, Sb: 0.01-0.05%, Cu: 0.05-0.25%, S: 0.01-0.03%, Ni: 0.05-0.2%, and the rest are Fe and unavoidable impurities.

The grain-oriented silicon steel provided in the embodiments of the present application has good magnetic properties and can be used to produce transformer cores.

In some embodiments, the value range of the magnetic induction B ₈ satisfies B ₈ ≥ 1.89T, and the value range of the iron loss P _17/50 satisfies P _17/50 ≤ 1.05W/kg.

Example

The following examples describe the content disclosed in the present application more specifically, and these examples are for illustrative purposes only, since various modifications and changes within the scope of the disclosed content of the application will be apparent to those skilled in the art. Unless otherwise stated, all parts, percentages, and ratios reported in the following examples are based on weight, and all reagents used in the examples are commercially available or synthesized according to conventional methods, and can be directly The instruments used without further processing, as well as in the examples, are commercially available.

Example 1 The cast slab was obtained by continuous casting according to the chemical composition described in Example 1 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 35%-45%. The slab is heated in a heating furnace at 1260°C for 100 minutes and then hot-rolled to a thickness of 2.3 mm. The hot rolling start temperature is 1142°C and the final rolling temperature is 938°C. After pickling, the hot-rolled sheet is cold-rolled to a finished product thickness of 0.27mm. Decarburization annealing is carried out for cold-rolled coils, in which the temperature rise rate in the temperature range of 500-750°C is 60°C/s, the decarburization annealing temperature is 833°C, and nitriding annealing is carried out after decarburization annealing, the nitriding temperature is 880°C, and the nitriding amount is 200ppm . After nitriding, apply MgO, after drying, perform high-temperature annealing according to the traditional process, after high-temperature annealing, apply an insulating layer and stretch annealing, and then perform laser scoring after stretching and leveling annealing.

Example 2

The cast slab was obtained by continuous casting according to the chemical composition described in Example 2 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 35%-45%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scoring in Example 1.

Example 3

The cast slab was obtained by continuous casting according to the chemical composition described in Example 3 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 35%-45%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing treatment-laser scoring treatment in Example 1.

Example 4

The cast slab was obtained by continuous casting according to the chemical composition described in Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 35%-45%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing treatment-laser scoring treatment in Example 1.

Example 5

The cast slab was obtained by continuous casting according to the chemical composition described in Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 35%-45%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing treatment-laser scoring treatment in Example 1.

Example 6

The cast slab was obtained by continuous casting according to the chemical composition of Example 1 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 21%. The billet is heated in a heating furnace at 1250°C for 90 minutes and then hot-rolled to a thickness of 2.22mm. The hot rolling start temperature is 1130-1140°C and the final rolling temperature is 930-1000°C. After pickling, the hot-rolled sheet is cold-rolled to a finished product thickness of 0.27mm. Decarburization annealing is carried out for cold-rolled coils, in which the temperature rise rate in the temperature range of 500-750°C is 55°C/s, the decarburization annealing temperature is 840°C, and nitriding annealing is carried out after decarburization annealing, the nitriding temperature is 860°C, and the nitriding amount is 210ppm . After nitriding, apply MgO, after drying, perform high-temperature annealing according to the traditional process, after high-temperature annealing, apply an insulating layer and stretch annealing, and then perform laser scoring after stretching and leveling annealing.

Example 7

The cast slab was obtained by continuous casting according to the chemical composition of Example 1 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 33%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scoring treatment in Example 6.

Example 8

The cast slab was obtained by continuous casting according to the chemical composition of Example 1 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 46%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scoring treatment in Example 6.

Example 9

The cast slab was obtained by continuous casting according to the chemical composition of Example 1 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 54%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scoring treatment in Example 6.

Example 10

The cast slab was obtained by continuous casting according to the chemical composition of Example 1 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 56%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing treatment in Example 6.

Example 11

The cast slab was obtained by continuous casting according to the chemical composition of Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 45%-55%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretching leveling annealing treatment-laser scribing treatment of embodiment 4, the difference is that during hot rolling, according to embodiment 11 in table 3 The slab heating temperature and finishing rolling temperature treatment.

Example 12

The cast slab was obtained by continuous casting according to the chemical composition of Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 45%-55%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scribing treatment of embodiment 4, the difference is that during hot rolling, according to embodiment 12 in table 3 The slab heating temperature and finishing rolling temperature treatment.

Example 13

The cast slab was obtained by continuous casting according to the chemical composition of Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 45%-55%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretching leveling annealing treatment-laser scribing treatment of embodiment 4, the difference is that during hot rolling, according to embodiment 13 in table 3 The slab heating temperature and finishing rolling temperature treatment.

Example 14

The cast slab was obtained by continuous casting according to the chemical composition of Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 45%-55%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretching leveling annealing treatment-laser scribing treatment of embodiment 4, the difference is that when hot rolling is according to embodiment 14 in table 3 The slab heating temperature and finishing rolling temperature treatment.

Example 15

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing treatment-coating insulating layer and stretching leveling annealing treatment-laser scribing of embodiment 5, the difference is that during continuous annealing according to embodiment 15 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Example 16

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scribing treatment of embodiment 5, the difference is that during continuous annealing according to embodiment 16 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Example 17

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretching leveling annealing treatment-laser scribing treatment of embodiment 5, the difference is that during continuous annealing, according to embodiment 17 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Example 18

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretching leveling annealing treatment-laser scribing treatment of embodiment 5, the difference is that during continuous annealing, according to embodiment 18 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Example 19

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretching leveling annealing treatment-laser scribing treatment of embodiment 5, the difference is that during continuous annealing, according to embodiment 19 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Comparative example 1

The cast slab was obtained by continuous casting according to the chemical composition described in Comparative Example 1 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 35%-45%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretch leveling annealing treatment-laser scoring treatment of Comparative Example 1.

Comparative example 2

The cast slab was obtained by continuous casting according to the chemical composition described in Comparative Example 2 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 35%-45%. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scoring treatment of Comparative Example 2.

Comparative example 3

The cast slab was obtained by continuous casting according to the chemical composition described in Comparative Example 3 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 35%-45%. Subsequent treatment is the same as hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scoring treatment in Comparative Example 3.

Comparative example 4

The cast slab was obtained by continuous casting according to the chemical composition described in Example 1 in Table 1, and the equiaxed crystal ratio (63%) of the cast slab obtained by adjusting the continuous casting process parameters. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing treatment-insulation layer coating and stretch leveling annealing treatment-laser scribing in Example 1.

Comparative example 5

The cast slab was obtained by continuous casting according to the chemical composition described in Example 1 in Table 1, and the equiaxed crystal ratio (67%) of the cast slab obtained by adjusting the continuous casting process parameters. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing treatment-laser scoring treatment in Example 1.

Comparative example 6

The cast slab was obtained by continuous casting according to the chemical composition described in Example 1 in Table 1, and the equiaxed crystal ratio (72%) of the cast slab obtained by adjusting the continuous casting process parameters. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing treatment-laser scoring treatment in Example 1.

Comparative example 7

The cast slab was obtained by continuous casting according to the chemical composition described in Example 1 in Table 1, and the equiaxed crystal ratio (77%) of the cast slab obtained by adjusting the continuous casting process parameters. Subsequent treatment is the same as the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulating layer and stretching leveling annealing treatment-laser scoring treatment in Example 1.

Comparative example 8

The cast slab was obtained by continuous casting according to the chemical composition of Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 45%-55%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scribing treatment of embodiment 4, the difference is that during hot rolling according to comparative example 8 in table 3 The slab heating temperature and finishing rolling temperature treatment.

Comparative example 9

The cast slab was obtained by continuous casting according to the chemical composition of Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 45%-55%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretching leveling annealing treatment-laser scribing treatment of embodiment 4, the difference is that during hot rolling according to comparative example 9 in table 3 The slab heating temperature and finishing rolling temperature treatment.

Comparative example 10

The cast slab was obtained by continuous casting according to the chemical composition of Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 45%-55%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scribing treatment of embodiment 4, and the difference is that when hot rolling is according to comparative example 10 in table 3 The slab heating temperature and finishing rolling temperature treatment.

Comparative example 11

The cast slab was obtained by continuous casting according to the chemical composition of Example 4 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 45%-55%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scribing treatment of embodiment 4, the difference is that during hot rolling according to comparative example 11 in table 3 The slab heating temperature and finishing rolling temperature treatment.

Comparative example 12

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scribing treatment of embodiment 5, the difference is that during continuous annealing according to comparative example 12 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Comparative example 13

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scribing treatment of embodiment 5, the difference is that during continuous annealing according to comparative example 13 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Comparative example 14

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scoring treatment of Example 5, the difference is that the continuous annealing is according to Comparative Example 14 in Table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Comparative example 15

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab obtained by adjusting the continuous casting process parameters was 37%-47%. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretching leveling annealing treatment-laser scribing treatment of embodiment 5, the difference is that during continuous annealing according to comparative example 15 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

Comparative example 16

The cast slab was obtained by continuous casting according to the chemical composition of Example 5 in Table 1, and the equiaxed crystal ratio of the cast slab was 37%-47% by adjusting the continuous casting process parameters. Subsequent treatment is similar to the hot rolling-cold rolling-decarburization and nitriding annealing-high temperature annealing-coating insulation layer and stretch leveling annealing treatment-laser scribing treatment of embodiment 5, the difference is that during continuous annealing according to comparative example 16 in table 4 The heating rate, decarburization temperature, nitriding temperature, and nitriding amount of the 500-750 ° C temperature range are treated.

The magnetic properties of the finished product are tested by the Epstein square circle method, and the magnetic properties are shown in Table 1-Table 4.

Table 1 Magnetic properties of finished products corresponding to different components

Table 2 Magnetic properties of finished products with different equiaxed grain ratios

Table 3 Magnetic properties of finished products corresponding to different hot rolling processes

Slab heating temperature (℃) Finish rolling finish temperature (°C) <![CDATA[P_17/50(W/kg)]]> <![CDATA[B₈(T)]]> Example 11 1153 935 1.059 1.892 Example 12 1220 945 1.008 1.902 Example 13 1250 950 0.983 1.911 Example 14 1280 958 0.962 1.916 Comparative example 8 1120 875 1.358 1.812 Comparative example 9 1145 930 1.118 1.874 Comparative example 10 1276 972 1.142 1.884 Comparative example 11 1315 975 1.137 1.879

Table 4 Magnetic properties of finished products corresponding to different decarburization and nitriding processes

As can be seen from Table 1, when the composition of the grain-oriented silicon steel of Examples 1-5 is within the scope of the application, the magnetic induction B of the finished product is _all above 1.89T, reaching the performance level of the grain-oriented silicon steel of high magnetic induction; If one or more steel components are not within the scope of the invention, the magnetic induction _B8 of the finished product is below 1.89T, which cannot reach the performance level of high magnetic induction oriented silicon steel.

It can be seen from Table 2 that when the equiaxed grain ratio of the slab structure of Examples 6-10 is above 60%, the average magnetic induction of the corresponding finished products is all below 1.89T, which cannot reach the performance level of high magnetic induction oriented silicon steel; Comparative Example 4 -7 When the equiaxed crystal ratio of the slab structure is below 60%, the average magnetic induction of the corresponding finished product is above 1.89T, and the iron loss is below 1.05W/kg, reaching the performance level of high magnetic induction oriented silicon steel.

It can be seen from Table 3 that when the slab heating temperature and hot rolling finishing temperature of Examples 11-14 are within the scope of the present application, the average magnetic induction corresponding to the finished product is all below 1.89T, reaching the performance of high magnetic induction grain-oriented silicon steel level; when one of the slab heating temperature and hot rolling finishing temperature of comparative examples 8-11 is not within the scope of the invention, the corresponding average magnetic induction of the finished product is all below 1.89T, and the iron loss is all above 1.10W/kg. To the performance level of high magnetic induction grain-oriented silicon steel.

It can be seen from Table 4 that when the decarburization and nitriding processes of Examples 15-19 are all within the scope of the present application, the magnetic induction B8 of the finished product is above 1.89T, reaching the performance level of high magnetic induction oriented silicon steel; Comparative Examples 12-16 If one or several of the decarburization and nitriding processes are not within the scope of the invention, the magnetic induction _B8 of the finished product is all below 1.89T, which cannot reach the performance level of high magnetic induction grain-oriented silicon steel.

The above is only a specific embodiment of the application, but the scope of protection of the application is not limited thereto. Any person familiar with the technical field can easily think of various equivalents within the scope of the technology disclosed in the application. Modifications or replacements, these modifications or replacements shall be covered within the scope of protection of this application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims (10)

1. The preparation method of the oriented silicon steel is characterized by comprising the following steps:

continuously casting to obtain a casting blank, wherein the casting blank comprises the following components in percentage by mass: c:0.03-0.09%, si:2.8-4.4%; als:0.015-0.030%, N:0.0050-0.0095%, mn:0.1-0.4%, sb:0.01-0.05%, cu 0.05-0.25%, S:0.01-0.03%, ni:0.05-0.2%, and the balance of Fe and unavoidable impurities;

and carrying out hot rolling, cold rolling, decarburization nitriding annealing, high-temperature annealing, insulating layer coating and stretching flattening annealing treatment on the casting blank to obtain the oriented silicon steel.

2. The method for producing oriented silicon steel according to claim 1, wherein in the step of obtaining the cast slab, the equiaxed grain ratio in the cast slab is 20% to 60%.

3. The method for producing oriented silicon steel according to claim 1, wherein the hot rolling treatment comprises: and heating the continuous casting billet to 1150-1280 ℃ for hot rolling, and controlling the final rolling temperature of the hot rolling to 890-970 ℃ to obtain a hot rolled steel plate.

4. The method for producing oriented silicon steel according to claim 3, wherein the cold rolling process comprises: and (3) performing primary cold rolling or secondary cold rolling with intermediate annealing on the hot-rolled steel plate to obtain a cold-rolled steel plate, wherein the reduction rate of the cold rolling treatment is more than or equal to 70%.

5. The method for producing oriented silicon steel according to claim 1, wherein the decarburization temperature satisfies 790 ℃ to 900 ℃ at the time of the decarburization nitriding annealing treatment.

6. The method for producing oriented silicon steel according to claim 5, wherein the temperature rising rate v at a temperature range of 500 ℃ to 750 ℃ satisfies 40 ℃/s to 70 ℃/s when the decarburization nitriding annealing treatment is performed.

7. The method for producing oriented silicon steel according to claim 1, wherein the decarburization nitriding annealing treatment comprises: at H ₂ +N ₂ +NH ₃ And (3) carrying out continuous decarburization nitriding annealing on the steel strip in the atmosphere, wherein the nitriding temperature is 800-950 ℃, and the nitriding amount b is 150-300 ppm.

8. The method of producing oriented silicon steel as claimed in claim 3, wherein the step of obtaining oriented silicon steel further comprises: after the decarburization nitriding annealing treatment, mgO is coated on the surface of the steel, and the high-temperature annealing treatment is performed after the MgO is dried.

9. The oriented silicon steel is characterized by comprising the following components in percentage by mass: c:0.03-0.09%, si:2.8-4.4%; als:0.015-0.030%, N:0.0050-0.0095%, mn:0.1-0.4%, sb:0.01-0.05%, cu 0.05-0.25%, S:0.01-0.03%, ni:0.05-0.2%, and the balance of Fe and unavoidable impurities.

10. The oriented silicon steel according to claim 9, characterized in that the magnetic induction B of the oriented silicon steel ₈ The value range of (2) satisfies B ₈ More than or equal to 1.89T, iron loss P _17/50 The value range of (2) satisfies P _17/50 ≤1.05W/kg。