DE1508366A1 - Process for making cast iron and low carbon steel with preferred crystallographic orientations - Google Patents

Description

Method of making cast iron and low carbon Steel with preferred crystallographic orientations

The invention relates to a method for producing oriented iron alloys and, in particular, a method for making preferred crystallographic Orientations in cast iron and low carbon steel, as well as the products obtained by this process.

It has been found that all metals and their alloys have a certain degree of preference for rolling Orientation and usually a different orientation obtained when cold worked and recrystallized are «when commercial iron and low-carbon steels are rolled into sheets or strips and recrystallized become, they have a poorly developed, after

Br.Ha / Ma

the

the Miller ¹ see indices with (100) / 01j7 denoted cubic orientation. This orientation has no particular value for the current use of cast iron and low-carbon steels.

Attempts have already been made to develop more favorable orientations in this material. For example, the initial chemical composition of the melt was varied by adding substances which prevent primary crystal growth. Other methods, including those operating at critical stress, have been used, varying the method and the degree of rolling and heat treatment. Nevertheless, up to the present invention, the preferred orientations have only been found in a relatively small number in the end product of crystals, namely in up to about $ 25> of the entire crystal structure.

It has now been found that cast iron or Armco iron and low carbon steel can be made so that they have at least two highly preferred crystallographic orientations, which are a polycrystalline Sheet metal or strip give very favorable properties «These textures are so pronounced that more than half the entire crystal structure has the preferred textures.

Cast iron or arraco iron and low-carbon steel is to be understood as meaning an iron material whose smelting plant is up to about 0.10 pounds of carbon, 0.10 to 0.40 # manganese (preferably about 0.03 to about 0.12 #), up to to about 0.05 i "sulfur, up to about 0.03% phosphorus, up to about 0.25 fi contains copper and the melt in the rest consisting of iron, up to the normal quantities of occurring in such materials contaminated rings. The cast iron and low carbon steel may also contain a small amount of aluminum. Silicon can also be present as a deoxidizer in small amounts or it can be added in amounts up to about 1.8 # to increase the dimensional stability of the product when used for magnetic purposes. The amount of silicon added can match that found in previously known non-oriented silicon steels and is derived from the phase boundary between alpha-iron and gamma-iron.The carbon and manganese content depends on whether the material is cast iron or low-carbon Steel is classified, where the latter usually contains over $ 0.05> carbon and over 0.20 + manganese.

the

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The two highly preferred crystallographic orientations cast iron and low-carbon steel according to the invention correspond to the Miller indices (Ι1θ) ^ δ "θΐ7 and (112) / T1O7. The (110 ^ OO ^ -Orientation is known · as is described below as Sossstruktur, has a cast iron and low carbon steel obtained according to the invention, material having this orientation certain magnetic properties, which are approximately just as good or even better than it oriented in a commercially available, 3 i "silicon-containing, silicon iron are found. So far ea was impossible to obtain highly oriented, low-carbon steel or cast iron with Goss structure without using ainde ~ least 2 1> silicon "

The (I12) / Tio7 orientation is a kind of cube eoctecure, which up to now has never been preserved in a substantial proportion in ferrous material. As follows is described in more detail, has an according to the invention obtained material with this orientation good deformability.

task

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The object of the invention is therefore the production of low-carbon iron or steel with pronounced (110) / $ 0i7 -orientation and also the production of low carbon iron or steel with highly developed (112) / Ti07 orientation.

The invention therefore relates to the creation of a method for producing highly preferred crystallographic ones Orientations in cast iron and low carbon steel.

Cast iron can be used according to the process of the invention and low carbon steel with a (11O) / o "Oji7 orientation obtained, with more than half of the entire crystal structure having this orientation.

The cast iron obtained according to the invention and the low-carbon steel with a cast structure are characterized by durohy superior magnetic properties.

The invention also provides a method of making cast iron and low carbon steel with a (112) ^ Tio7 orientation, being more than half of the entire crystal structure sioh duroh this orientation distinguishes

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The cast iron obtained according to the invention and the low-carbon steel with the (112) / T1 ^ orientation are characterized by good deformability.

The invention is explained in more detail by the following statements in conjunction with the drawing. In the Drawing show:

Fig. 1 is a photomicrograph enlarged 50 times, which is the preferred, even, fine-grained Shows the structure of the hot-rolled material according to the invention,

2 is a photomicrograph enlarged 50 times,

which the hot-rolled material according to the invention shows with undesirably large crystals on the surfaces,

3 is a photomicrograph, magnified 100 times, showing a hot rolled material in which large surface crystals such as those shown in Figure 2 are not refined and persist after rolling and decarburization,

Fig. 909843/0720

Pig. 4 a photomicrograph in 100x magnification, which shows a warning rolled material in which large surface crystals are not refined and after cold rolling, decarburization and the the annealing annealing remains,

Pig. 5 a photomicrograph enlarged 100 times, which the inventive material after Hot rolling, cold rolling and decarburization shows, with the crystals after hot rolling in are in an ideal state,

Pig. 6 a (100) optical pole figure, which is oriented Shows iron with an (i10) / 0 £ i7 texture

Pig. 7 a (100) -optisohe following figure, which is oriented Shows iron with a (112) / TiCj7 texture, and

Pig. Fig. 8 is a graph comparing the DC magnetization curves for oriented cast iron of the present invention with the curves for conventional magnetic cast iron, non-oriented silicon steel and oriented 3 % silicon steel.

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In short, the invention is based on the finding that the recrystallization texture τοη Gruse- ' iron and low carbon steel can be changed as a result It is possible that the final treatment step is the growth of crystals with the preferred orientations at the expense of crystals with other orientations, which process promotes secondary recrystallization o In current practice, the manufacturer of low carbon ferrous material turns to Achieving a desired final thickness hot and cold rolling and annealing slightly below the A ^ or the lower critical temperature for softening the material through recrystallization of the crystal structure at. It has been found that if the material is subjected to higher temperatures during this final annealing or if it keeps the temperature for a longer period of time, the grain size increases, but this has little effect on the orientation the crystals wields. This is due to the fact that the material is more of a primary recrystallization and an arbitrary and non-selective crystal growth as a secondary recrystallization with selective Undergoes crystal growth.

A pronounced preferred orientation can according to the invention can be achieved by adding sulfur to the

909843/0720 grain boundaries

The grain boundaries of the primary grains or crystals can diffuse and thereby limit their growth, Das enables secondary recrystallization with the results given above.

Bas cast iron or the low carbon steel can be made by any known melting and tempering process can be obtained. When using low carbon steel, this can be either calmer or calmer Be steel; however, if it is killed steel, silicon killed steel is preferred. Bas low carbon Iron or steel can be cast continuously or at intervals to form blocks, billets or slabs will. Bas material can be of any thickness, depending according to the rolling equipment used, hot rolled · Depending on the cold deformations that follow hot rolling and the desired final thickness of the end product can be the kink of the hot rolled strip at a current time Setup can vary between approximately 0.318 and 0.127 cm.

Bas hot rolling can be related to the temperature of the goods when heating before rolling, when entering the rolling mill, during rolling on the various between « temporal strengths and during the cooling down to room temperature can be varied. These temperatures stand

909843/0720 both

for both cast iron and low carbon Steel), depending on the end uses, determine these Guidelines can also be followed for the material of the invention.

However, it is important that the grain size of the material after hot rolling and before cold rolling through the entire thickness of the material relatively is small and uniform. For this reason, the preferred temperature is at the completion of hot rolling of low-carbon steels to achieve a fine grain structure above about 871 C. One such desirable fine grain structure is in Pig photomicrograph. 1 shown. Cast iron is used at finish-rolled at a lower temperature in the usual way. For both cast iron and low carbon For steel, coiling temperatures below 704 G are preferred to prevent excessive grain growth.

In order to surely achieve a uniform, fine grain structure after hot rolling, the material can be one open annealing or normalizing heat treatment. Although during this stage of the procedure decarburization can take place, the carbon is preferably formed in a later stage.

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removes, as described in more detail below. The Hauptsweck of the hot rolling subsequent heat treatment consists of refining and stabilization of the grain structure · This can be done by a continuous or Strangnornalisierungsglühung, critical in a short-time heating above the A, or upper funct (about 885 ⁰ C) consists. A temperature of about 982 ⁰ C is sufficient · It has been found that when remain after the hot rolling large grains at the Materialoberfläohe (as gaseigt in Fig x 2), which is in the interior of a package obtained in verhältnisnäesig high temperature of the case, and if these large grains are not refined by high-temperature annealing, they will also persist during a later decarburization (see Fig. 3) and during the subsequent annealing (see Fig. 4). Fig. 5 is a photomicrograph showing the ideal grain structure After the decarburization, _f shows where the grain structure according to the warm orphans corresponded roughly to that shown in Fig. 1 or was refined by a normalization annealing.For economic reasons, it is advisable to obtain a grain structure of the type shown in Fig the normalization annealing can be omitted

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It was also found that when initial annealing after hot rolling at temperatures below of the upper critical point. they have almost no influence on the grain structure of the material, if such annealing is less lasts than 5 minutes · For longer times, a grain growth and decarburization takes place and a later one secondary grain growth is more difficult to achieve

The cast iron or low carbon steel having a crystal state similar to that shown in Fig. 1 is cold rolled in one or more stages to achieve the desired final thickness. As is clear to the person skilled in the art, a single-stage cold reduction is often preferred for economic reasons, since a multi-stage cold reduction requires annealing between the individual stages. If a multi-stage Kaitverminderung is required to the intermediate annealing in an open Ausglühung at a temperature between about 593 and about 982 ⁰ C in a reducing atmosphere, optionally a decarburizing atmosphere, if a dressing is to be avoided, consist. If the atmosphere is oxidizing, pickling is required.

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If the end product is to have a large structure,

If the degree of cold reduction of less than 90 i "in each stage. Reductions between about 50 and 83 # have been found to be satisfactory

If the end product is to have a (i12) / TiC> 7 rating, the cold reduction in a one-step process should be 90 1> or more. With a successful end in two or more stages cold reduction with intermediate annealing only the last cold rolling has a reduction of 90 i "or make more. Reductions of 90 # have proven to be excellent for achieving a (I12) / Tio7 orientation in general for the end product. The maximum reduction is limited only by the capacity of the mill and the ability of the material to withstand drastic deformation.

While the above to achieve the two types the cold reduction ranges given by the crystal orientation are fairly accurate, the hot rolling conditions the chemical composition and the final strength have a certain influence on the tendency to form one or the other type of orientation.

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As already mentioned, decarburization can be carried out before cold rolling · Two-way. Atmosphere at about 816 ⁰ G, as is known to those skilled in the art. The temperature can vary between 649 and about 871 0 and cheaper hydrogen-containing gases, eg diassosed ammonia, can be used · The final carbon content should be less than 0.01 pounds and for some uses less than 0.005 1 · Kistenglühung done · during decarburization or during one of the other heat treatments can also be nitrogen to less than 0,001 are i »nitrogen removed ·

The final treatment consists of a box annealing at a temperature just below the upper critical or A, temperature in a reducing, non-oxidizing atmosphere. The iron or the low-carbon steel must be kept in the alpha phase; due to the carbon loss during the decarbonization is the upper critical temperature or the A, -temperature but then at about 899 C · Approximately 843 ⁰ C are then

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sufficient if at temperature for 48 hours or more · A preferred temperature range is «Between about 871 and about 899 ° C, and within one In limited temperature ranges, the time while which is held at the temperature is less than 24 hours *

As the annealing of open coils progresses, decarburization and nitrogen removal can take place and the final annealing in a single furnace done by changing the temperature and atmosphere in the same way as when a strand anneal followed by a box glow

A distinctly preferred orientation can be obtained in the cast iron or the low carbon steel by adding sulfur to the grain size Primary crystals can diffuse, which limits their growth and a secondary recrystallization with selective grain growth is made possible · It takes place this by treating the cast iron or the low carbon steel with carbon dioxide or sulfur compounds near reaching the final strength and immediately before or during the part of an annealing which results in a primary grain growth There are various possibilities for this

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The invention can be carried out using ferrous sulfide or other sulfur compounds, which dissociate or decompose at the temperatures of the primary grain growth, that during the abeohliessende Annealing used annealing separator adds. Elemental sulfur can also be the same in the separator Purpose to be added.

Preferred annealing separators are magnesia, aluminum oxide or calcium oxide or mixtures thereof in fine ' part shape; other substances can also be used if necessary, e.g. titanium oxide and other high-melting points Metal oxides

The final annealing, which can include both primary and secondary recrystallization, usually consists of annealing in dry hydrogen in a muffle or box furnace. That the Material subjected to annealing can either be in the form of stacked sheets or coils? if the If the annealing atmosphere is to act on the cast iron or the low-carbon steel, excellent results are obtained Results of the annealing of loose wraps obtained by modern methods. Regardless of the material is present as a stack of sheets or as a roll, should be preferred

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the amount of sulfur-containing substance on the surfaces of the goods within certain specified below Limits are kept. It is believed that the sulfur or the sulfur-containing compound is associated with the dry, hydrogen-containing annealing atmosphere with formation reacts with hydrogen sulfide; that the sulfur is then transferred to the hydrogen sulfide as a carrier Steel is transferred and the hydrogen sulfide then with the steel forming sulfides at the grain boundaries reacted. The reaction occurs at an oven temperature between about 538 and 899 ° 0 Sulfur absorption sets in high sulfur concentrations at the grain boundaries of the primary structure, what the primary grain structure prevents such grain growth as the subsequent secondary recrystallization would disturb. In this way a fine-grained matrix is preserved until secondary crystals with the preferred one Orientation the crystals with other orientations start to use up. Then continue with increasing Temperature the secondary grain growth continues through grain boundary energy and transforms the fine-grained matrix into a well-developed structure with preferential orientation around.

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From the above explanations it follows that the sulfur or a sulfur-containing compound can be added instead of adding to the annealing separator while achieving comparable results in the annealing atmosphere in the form of hydrogen sulfide or another gaseous sulfur compound, e.g. sulfur dioxide, sulfur bacafluoride and the like, which Compound then reacts at the grain boundaries at temperatures at or slightly above 338 ^{° G.} This can happen during the primary grain growth period, which occurs during the heating of the material to the temperature at which secondary recrystallization occurs in a final anneal. Selenium or hydrogen selenide behave similarly to sulfur or hydrogen sulfide, although these substances are more expensive; they are therefore considered to be the equivalents of sulfur and hydrogen sulfide.

In yet another embodiment, the sulfur can or the sulfur-containing compound on the surfaces of the sheet material during a decarburization annealing be present for the final annealing. For example, if the cast iron or low carbon steel belt through a special atmosphere for removing carbon containing, elongated furnace is performed, one can

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Hydrogen sulfide with the decarburization atmosphere with the formation of a regulated iron sulfide film mix with the material, which PiIm lasts during the subsequent final annealing primary grain growth prevented

They amount of elemental sulfur or of sulfur in the form of a sulfur-containing compound, which is added to the annealing separator, about 1/2 to 10 wt. based on the annealing separator, if this is in an amount of about 5 kg per, ton of cast iron or low carbon steel is applied. It was found to be within this sulfur addition range Secondary crystals produced have a tendency to become larger with increasing addition of sulfur. The amount ▼ On the cast iron or the low carbon steel accessible sulfur can reduce the solubility of sulfur in the Exceed the range of grain boundaries. Some sulfur goes off during the drying of a coating slurry and handling of the dried coating is lost. Therefore you have to add a surplus to compensate for this loss and use the values given in all cases to those during the annealing treatment Amount of sulfur or sulphide present.

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As already mentioned, hydrogen sulphide or other sulphurous gases can be added to the annealing atmosphere instead of adding sulfur to the annealing separator. In this case and assuming that the atmosphere Have free access to all surfaces of cast iron or low carbon steel are said to be in the atmosphere at least 750 ppm hydrogen sulfide or its Be included equivalent. However, larger ones can also be used Add amounts of sulphurous gases, even like that large amounts that an iron sulfide film or an iron sulfide surface layer forms, as shown in FIG Belgian patent 665 687 is described. When the cast iron or low carbon steel undergoes an annealing treatment, e.g. a decarburization annealing, before the final Is subjected to annealing, the sulphide film and the sulphides are formed before the final annealing then diffuse into the grain boundaries of the primary crystals during the final annealing.

The total sulfur content of the cast iron or low carbon steel is not necessarily important. The presence of finely dispersed sulfides at the grain boundaries during the final annealing is of primary importance. It follows that a low carbon 909843/0720

poor steel or cast iron with sufficient sulfide concentration at the grain boundaries for a primary and secondary grain growth may be suitable even if the total sulfur content is relatively low is, while a treatment which causes sulfides to be removed from the grain boundaries, the ability of the Materials can impair the ability to acquire a distinct, preferred orientation, even if through this Treatment does not significantly reduce the total sulfur content of the material. In carrying out the invention therefore, some sulfur or sulfide will be added to the cast iron or low carbon steel after rolling on the Final starch, essentially independent of its total sulfur content, . added, especially since the methods described here for adding sulfur or sulfide i # make themselves felt primarily at the grain boundaries.

Too much sulfur can affect the properties of iron or steel. Although limited Quantities can be removed at annealing temperatures below 899 ° C, the sulfur is thereby in the Usually not reduced considerably.

If an iron sulphide film is formed on the metal surfaces, e.g. by mixing sulfur water

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With the decarburizing atmosphere, the iron sulfide layer should be about 0.02 to about 0.10 mils thick.

The application of a vacuum annealing is in the case of the invention Procedure not excluded. Nitrogen or another inert gas can also be used with or can be used without hydrogen or in a partial vacuum. Sulfur can obviously be from the Diffuse annealing separator directly into the metal

example 1
One-step process for generating a (112) / Ti ÖJ texture

Melt analysis t

Carbon 0.010 i »

Manganese 0.965 Ί »

Sulfur 0.025 *

The stages of the procedure;

1. The stock was hot rolled down to 0.100 inches.

2. The material was then pickled.

3. The material was 92jiiger Dick Ever * mak- ing any changes to 0.008 inch cold slipped down waist.

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4. The material was decarburized in a strip anneal by heating it for 4 minutes in feuohteo hydrogen to 816 ⁰ G, up to a carbon content of about 0.004 J *.

5. The material was coated with magnesia containing 8% sulfur.

6. The material was calcined in a dry hydrogen atmosphere at 882 ^° C. for 16 hours.

The final product had a pronounced (112) / Tio7 texture and very good deformability.

Examples 2 and 3

The following table 2 gives the final strength, the percentage reduction in dioker, the type of treatment, the magnetic Properties and the type of orientation achieved for five different samples. All samples were ron the same hot rolled coil as in Example 1 was taken.

The low-carbon steel was cold-rolled, decarburized in a strip annealing at 816 ° C., with 4 wt. # Elementary Sulfur containing magnesia coated and 24 hours

at 909843/0720

box annealed at 888 ^{U C,}

Tabel

Final strength

i » cold deformation

Procedure

permeability
at H-1O
Örsted

Type of orientation

Ex. 1 0.017 in

Ex. 2 0.015 inches 70+

single stage 1820

two-stage * 1762

Secondary crystals with a large structure

Secondary crystals with a large structure

* The material was in the first cold rolling step 70 Ji to an average thickness of 0.030 inches and about 50 * f "in the second stage to the Bndstärke of 0.015 inches reduced.

Examples 4t 5 and

Another group of samples were taken from a cast iron melt with the following melt analysis:

carbon

manganese

sulfur

0.015
0.052
0.022

That

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The material was hot rolled down to a thickness of 0.100 inches and annealed at about 816 abschiiessend ⁰ C. The hot rolled strip was normalized and pickled in a belt furnace at 982 ° C. After a one-step, different thicknesses, shown in the following Table 3, cold rolling the material is decarburized at 816 0, coated with 4 $> elemental sulfur-containing magnesia and by box 24 hours at 871 ⁰ C. The permeability was excellent for all strengths, which indicates that the product has a pronounced G-oss structure

Table 3

Final thickness # Cold forming permeability forming at H »10 Örsted

Example 4 0.025 inch 62 1885

Example 5 0.014 inch 79 1892

Example 6 0.011 inch 83 1835

Examples 7 to 12

The magnetic properties of material treated according to the invention were determined for cast iron samples with the the following melt analysis determined:

Carbon 909843/0720

carbon

manganese

sulfur

0.020 0.045 0.023

The stock was cold rolled down to 0.065 inches and normalized in a belt furnace at 982 ° C. After pickling samples were cold rolled down to six different final thickness, decarburized for 5 minutes at 816 ⁰ C in wet hydrogen, coated with a slurry of 2 1/2 # elemental sulfur-containing magnesia and by box 24 hours at 888 ⁰ C.

Final strength

Table 4

i » Cold permeability core loss Watt / Lb. formation did at H * 10
örsted

P10; 60 P15; 6O P17; 60

is] ?. 7th 0.025 customs 62 η 8th 0.0185 It 72 Il 9 0.014 It 79 η 10 0.011 It 83 Il 11 0.009 It 86 Il 12th 0.006 It 70 + 70

1880 1, 55 3, 9 5.5 1924 1, 05 2, 4th 3.3 1942 O, 90 2, 0 2.6 1960 O, 80 1, 6th 2.05 1939 ° » 75 1, 45 1.8 1889 0, 65 1, 25th 1.65

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the

The excellent core loss values of the erfindungsgemäseen materials are at high frequencies auegeprägter · The materials of Example 9 and 11 were at a frequency τοη 400 ms and at inductions yon ₁ 1O 15 and 17 Kilogaues tested. The results are summarized in Table 5.

9
11 Table 5 Core loss
Watt / Ib. P17J400 P15; 400 65
33 P1O.-4OO 47
25th example
example 17th
11

Tables 4 and 5 clearly show that the permeability and the values for the core loss of the Materials are excellent, indicating that a distinct cast structure existed in all of these samples.

In Fig. 8 are the DC magnetization curves for the materials of Examples 7, 8 and 9 with the DC magnetization curves for common cast iron, non-oriented silicon steel and oriented 3 # silicon

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steel recorded. As can be seen from Fig. 8, he « the cast iron treated according to the invention requires a significantly lower magnetization strength until it is reached the same induction as commercial cast iron and non-oriented silicon steels. With magnetization strengths of about 1 Örsted and higher, the cast iron obtained according to the invention is cheap with the comparable to more expensive, oriented 3 # silicon steels.

The effective sulfur content in the vicinity of the steel is intended to be maintained during the primary grain growth period until the steel has reached a temperature of about 816 to 871 ⁰ O. The grain growth is then sufficiently inhibited and the crystals with the preferred orientation become free and can thus determine and control the final orientation of the product during the secondary grain growth. Generally speaking, the effective amount of sulfur in practicing the invention can be given as follows:

1) When adding elemental sulfur, e.g. as yellow sulfur powder or sulfur bloom, to an annealing separator, about 1/2 to about 10 f> sulfur, based on the weight of the coating, are used,

if

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if this coating is used in the thicknesses customary for annealing separators.

2) When using ferrous sulphide for the delivery of sulfur to the annealing separator should be about $ l / K) to 1 wt.> Contain this compound ·

3) When hydrogen sulfide of a decarburizing atmosphere for the formation of an iron sulfide film to control the primary grain growth in a subsequent annealing is added, the treatment should be controlled to produce a sulfide film about 0.1 to 0.02 mils thick trains.

4) In any case, regardless of whether sulfur is added to form an iron sulfide film or whether sulfur is added to a final annealing during the primary grain growth period, or whether it is added to the annealing atmosphere or to the annealing separator or both, the best results are achieved when the so added amount of sulfur to the sulfur content of the cast iron or low carbon steel is increased by no more than about 0.005 i "and by not less than about 0.001 $> at the time in welohem the steel during the final annealing, a temperature of about 871-899 ° Has reached 0.

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It has also been found that if the low carbon steel or cast iron has a high manganese content, the addition of sulfur to the annealing separator must be increased for best secondary growth. For this reason, the manganese content should expediently be below about $ 0.2.

As can be seen from the preceding examples, the differences in the treatment of the cast iron determine or low carbon steel largely whether in the end product a cast structure or a cube " corner orientation or a mixture of the two Orientations is achieved. Pig. 6 is a pole figure showing the orientation of the material of Example 7 shows. As you can see, the pattern clearly shows a pronounced (i10) / 0 "0j £ 7-0 orientation.

Figure 7 is a pole figure showing the orientation of the material of BeJEtp. 6 and shows the pattern a pronounced (112) / Ti0J7 orientation to

Me grain size according to the invention as the end product obtained materials is relatively large. While the A.S.T.M. Grain size standard table a Provides 100-fold enlargement, the grain sizes can

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the materials obtained according to the invention are compared with the S.D.T.M table at the same magnification, and in this comparison generally correspond to No. 8 to No. 00 and even greater. Besides, they are Crystals usually at least about 10 times as long as the sheet metal is thick.

As already stated, the generation of a (112) / T1O7 ~ increases Orientation in cast iron or low carbon steel the deformability of the product is essential, despite a relatively large grain size.

The invention can be modified widely without departing from its scope.

Patent claims

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Claims (1)

Claims 1) Process for the production of cast iron and low-carbon steel sheet with a pronounced (110 ) / j5oiJ- or (112) ^ Ϊ1 (^ -orientation, characterized in that one up to 0.10 1> carbon, 0.01 to 0 , 40 Ji Hangan, material containing up to 0.05 # sulfur and, apart from incidental impurities, consisting of iron, is hot rolled into a strip of medium thickness, this hot rolled strip is cold rolled down to the final thickness, the cold rolled material is then subjected to a final annealing subordinates that during the primary grain growth period of this annealing the presence of elementary sulfur, selenium and / or decomposable compounds of the same is provided and then the material is subjected to a box annealing which causes secondary recrystallization at a temperature between 816 and 899 ° C. 2) The method according to claim 1, characterized in that the iron and the steel up to 1.8 ^ silicon contain. 909843/0720 3) Method according to claim 1, characterized in that that the cold-rolled product is before the final one Annealing is subjected to a decarburization annealing. 4) The method according to claim 1, characterized in that the hot rolling of the low-carbon steel at a temperature above about 871 ⁰ C is ended. 5) method according to claim 1, characterized in that that subsequent to the hot rolling, a normalizing strand annealing is carried out to achieve a uniformly fine grain structure. 6) The method according to claim 1, characterized in that to achieve a predominant (112) ^ 107 orientation when rolling down the material cold the final thickness is at least a 90% reduction in thickness is carried out. 7) Method according to claim 1, characterized in that, in order to achieve a predominant (110) / Ü0jy ~ orientation, the material is cold-rolled to achieve the final thickness with a thickness reduction of less than $ 90. 909843/0720 δ) Method according to claim 1, characterized in that that the material is cold rolled to the final thickness in two stages and one between the two stages. Annealing is switched on. 9) Method according to claim 1, characterized in that that sulfur is added to the material during the primary grain growth period of the final annealing will. 10) The method according to claim 3, characterized in that the material sulfur from an external source during the decarburization treatment in a sufficient amount to form a thin ferrous sulfide film on the material Amount is supplied. 11) Cast iron and low carbon steel sheet, labeled through a pronounced (110) / 0 "0i7 orientation. 12) cast iron and low carbon steel bleoh, featured due to a pronounced (112) / Tio7 orientation. 909843/0720 13) Gruss iron and carbon poor sheet steel, characterized by a predominant ( '\' \ O) / j5oY7- or (112) / Ti (^ / - orientation and at least 10 times the Bleohdicke amount forming length of the crystals. 9098Α3 / 072Θ Blank page