JPH1081915A - Manufacture of two directional silicon steel sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacture of a silicon steel sheet excellent in magnetic properties in two directions orthogonal to each other. SOLUTION: A steel, having a composition which contains, by weight, 0.02-0.2% C and in which the contents of Si and Mn satisfy inequalities Si(%)+0.5Mn(%)<=4, Si(%)-0.5Mn (%)>=1.5, and Mn(%)>=0.2, is rolled in two directions orthogonal to each other, by which a steel sheet is prepared. Then, annealing is applied under reduced pressure to the steel sheet by using, as a separation agent at annealing, a substance accelerating decarburization or a substance accelerating decarburization and a substance accelerating Mn removal. Further, rolling in two directions orthogonal to each other is carried out in the α+γ two-phase temp. region and then rolling is performed in one direction in the α-phase temp. region, or, rolling in one direction is carried out in the α+γ two-phase temp. region and then rolling is performed in a direction orthogonal to the rolling direction in the α-phase temp. region.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a magnetic steel sheet having excellent magnetic properties, which is applied to a small transformer or the like.

[0002]

2. Description of the Related Art Silicon or steel sheets are used as core materials for motors, generators, transformers and the like, and these steel sheets are required to have low loss during use and high magnetic flux density.

Conventionally, there are non-oriented electrical steel sheets and oriented electrical steel sheets (or oriented silicon steel sheets).
Normally, in order to suppress the generation of eddy currents and reduce iron loss, the magnetic core is usually formed by laminating thin magnetic steel sheets. In this case, the direction of magnetization is parallel to the plate surface. In the case of non-oriented electrical steel sheets, as long as the magnetization direction is parallel to the plate surface, the magnetic properties are good in any direction, and they are preferably used for small motors and the like. On the other hand, grain-oriented electrical steel sheets show particularly excellent magnetic properties when magnetized in a specific direction parallel to the sheet surface, that is, usually magnetized in a direction parallel to the rolling direction of the sheet, but in other directions. Magnetization is inferior to non-oriented electrical steel sheets. For this reason, it is applied to the manufacture of transformers with even less loss, such as winding cores or lamination in combination so that the rolling direction of the plate always coincides with the direction of magnetization.

[0004] Iron crystals have magnetic anisotropy. If a model of a single crystal of iron is a cube, the magnetic properties when magnetized in the direction perpendicular to the plane of the cube, that is, in the <001> axis direction. Is the most excellent. In grain-oriented electrical steel sheets, most of the iron crystal grains that constitute it have a <001> axis parallel to the rolling direction,
The {110} plane is aligned in a direction parallel to the plate surface.
This {110} <001> direction is usually called Goss direction.
Non-oriented electrical steel sheets are manufactured under almost the same manufacturing conditions as ordinary cold-rolled steel sheets, whereas in the production of grain-oriented electrical steel sheets, the chemical composition of the steel is different, but after cold rolling strain relief annealing. Further, by annealing at a high temperature, with the help of a sulfide or a nitride called an inhibitor, the crystal is manufactured by selectively growing crystal grains having a Goss orientation.

[0005] Such a grain-oriented electrical steel sheet has excellent magnetic properties in the rolling direction, but <001 in other directions.
> Poor magnetic properties due to almost no axes included. For this reason, a sufficient effect cannot always be obtained in a usage such as an EI core in which a direction parallel to the rolling and a direction perpendicular to the rolling are simultaneously magnetized.

On the other hand, if a steel plate made of a crystal having the <001> axis parallel to the rolling direction and the {100} plane being parallel to the plate surface is obtained, the direction parallel to the rolling is obtained. Both perpendicular directions have excellent magnetic properties, and it is expected that a highly efficient and compact transformer can be obtained with a normal EI core or L core laminated core without having a shape like a wound core. Various methods for producing such an electrical steel sheet having the {100} <001> orientation have been studied for a long time. However, in reality, such a steel sheet has not yet been manufactured.

[0007] Recently, electrical steel sheets have been developed in which the {100} plane of the crystal in the steel sheet is parallel to the plane of the steel sheet while the conventional grain-oriented electrical steel sheet has the Goss orientation as the preferred orientation. .
The invention disclosed in Japanese Patent Application Laid-Open No. 1-108345 discloses that the <001> direction of the axis of easy magnetization is included in a plane parallel to the steel sheet and takes various directions. Although named, it is preferable for an application such as a motor in which the direction of magnetization takes any direction in the plane of the plate.

[0008] In this method for producing an electromagnetic steel sheet having a {100} plane parallel to the steel sheet, a steel sheet of a predetermined thickness containing C, Mn and Si is heated first, and then a vacuum or weak decarburization is applied. Slow decarburization is performed in the atmosphere. In this case, the decarburization temperature is such that the steel is in an austenite (γ) region or a two-phase region of austenite + ferrite (γ + α),
If the C concentration is decarburized to an extremely low concentration that is sufficiently lower than 0.01%, the range is set so that a complete ferrite (α) phase is obtained. Then, by slow decarburization, the <001> axis on the surface, in the direction perpendicular to the plate surface, or {100} parallel to the plate surface
Crystals with planes are generated at high density.

[0009] Then, the strength at decarburizing atmosphere, the interior of the steel at a temperature below the temperature range of the primary decarburization annealing and the at least _one point A, performs a secondary decarburization annealing , Α from the surface
The grains are grown and the entire steel sheet is sufficiently decarburized. Then, it can be said that an electromagnetic steel sheet having a very large number of crystals having a {100} plane parallel to the sheet surface can be obtained.

[0010] Crystals having {100} planes parallel to the plate surface in the surface layer develop well, especially under mild decarburization conditions.
It is considered that the ferrite grains grow preferentially because the surface energy of the {100} plane is smaller than the planes of other orientations, and that the difference in energy is due to the fact that the thinner the α phase layer, the greater the energy difference. Then, the surface grains formed in this manner serve as nuclei, and grow into the inside of the steel sheet while transforming from the γ phase to the α phase by decarburization.

Further, the invention presented in Japanese Patent Application Laid-Open No. Hei 7-73542 discloses that the generation and growth of crystal nuclei having a {100} plane parallel to the plate surface on the above-described surface are caused by the oxide-based annealing separation. It can also be realized by performing decarburization annealing under reduced pressure using a tight coil or a laminated plate in which the agent is sandwiched between layers. In particular, when increasing the annealing temperature to shorten the processing time and to further develop the {100} plane orientation, it is necessary to open the gap between the layers of the sheet in the decarburization treatment using atmospheric gas. The deformation of the steel sheet at a high temperature caused by opening the gap cannot be dealt with by a slight modification, and cannot be used as an electromagnetic steel sheet used for lamination. On the other hand, such a deformation can be prevented by laminating with an annealing separator interposed therebetween.

Further, by selecting an annealing separator, it is possible to remove Mn in the decarburization annealing process, but the removal of Mn has the effect of further promoting the development of the {100} plane orientation. And

The {100} plane orientation formed in this manner does not have a specific directionality in the plane of the plate, and is effective when applied to a case where the magnetization direction rotates like a motor. . However, it is not necessarily sufficient when transformers having excellent magnetic properties in two orthogonal directions are required, such as an EI core or an L core of a transformer.

[0014]

SUMMARY OF THE INVENTION The present invention relates to a method of manufacturing an electromagnetic steel sheet which is suitable for applications such as an EI core of a small transformer, and in particular, has excellent magnetic properties in two directions, namely, a rolling direction and a direction orthogonal thereto. Is provided.

[0015]

Means for Solving the Problems The present inventors have developed a magnetic steel sheet having a {100} <001> cubic crystal orientation based on a method of developing a {100} plane orientation using such surface energy. Were investigated in various ways. The {100} plane orientation crystal is formed by the difference in surface energy from other plane orientations in the α phase due to transformation from the α or γ phase recrystallized on the steel surface. However, those having a specific axial direction are difficult to be formed. However, the results of this investigation found that the texture of the base steel before decarburization annealing affected the axial direction of the formed {100} crystal grains. The effects of the rolling reduction, intermediate annealing, and the application of warm rolling were investigated.

As a result, although it cannot be realized only by ordinary one-way rolling, in a rolling process including hot rolling and cold rolling, orthogonal rolling in two directions of an original rolling direction and a direction orthogonal thereto is performed. In the final annealing by {100} <
It was found that a cubic orientation of 001> was obtained. Such orthogonal rolling is generally performed at the stage of cold rolling, and even when obtaining the {100} plane orientation, orthogonal rolling in cold rolling is effective for aligning the <001> axis. Met.

However, if the steel composition is limited, it is possible to perform {100} <00 in the final annealing by performing orthogonal rolling not only in the normally conceivable cold rolling stage but also in the hot rolling stage.
It became clear that 1> direction could be obtained. That is, if orthogonal rolling is performed at the stage of hot rolling, the subsequent cold rolling is sufficient in normal unidirectional rolling only {100} <001>
The cubic orientation is obtained by hot rolling and then cold rolling in the width direction of the steel sheet.
001> orientation was obtained. Thus, the fact that the orthogonal rolling may be performed at any stage including the hot rolling and the cold rolling is a very advantageous event in the field of actual production of this steel sheet.

The cubic orientation of {100} <001> can be obtained by performing orthogonal rolling because the rolling texture of the α-phase remaining in the substrate during the formation of the {100} plane orientation in the surface layer is affected. It was thought that it was. As described above, the initial crystal of the {100} plane orientation has a specific axial direction with respect to the plate surface direction in the thin α phase generated by decarburization of the steel surface of the γ phase or γ + α phase. It is formed without lingering. Here, it was presumed that the texture of rolling existing in the base steel had to be greatly involved in order to orient the crystal grains of the initial {100} plane to the specific axis <001> as much as possible.

The rolling texture is generally not significantly formed by rolling in the temperature range of the γ phase, and the texture of the α phase or α + γ
Introduced by rolling in the phase zone. Also, even if α
Even if a texture is formed by rolling in a phase, it is randomized during transformation from the α phase to the γ phase by heating. Therefore, in order to leave as much of the texture of the rolling as possible and to form a thin α phase by decarburization on the surface during the final annealing, the substrate heated to the decarburization temperature must contain Therefore, it must be a γ + α phase which has the effect of the rolling.

By decarburization or decarburization and de-Mn
In the range of steel composition suitable for developing {100} plane orientation,
Investigation of the composition that can obtain stronger orientation in the {100} <001> direction by orthogonal rolling revealed that it was sufficient to use α + γ two phases in the hot rolling stage. Normally, hot rolling of steel is performed in the high γ phase temperature range. Therefore, clear rolling texture does not remain because the process goes through two-stage randomization of recrystallization and transformation. On the other hand, α
In hot rolling in the two-phase region of + γ, a clear rolling texture remains.

Therefore, further consideration was given to the chemical composition, rolling conditions, decarburization treatment conditions, etc. in consideration of the rolling workability, magnetic properties, and the range of formation of the two-phase structure of the steel, and such remarkable {100} < The present invention has been completed by clarifying the range of optimal manufacturing conditions for obtaining a cubic orientation of 001>. The gist of the present invention is as follows.

(1) C: 0.02-0.2% by weight of Si
A steel sheet obtained by rolling in two directions orthogonal to each other by using a steel having a content of Mn and Mn that satisfies the following formula is used as an annealing separator, a substance that promotes decarburization or a substance that promotes decarburization. A method for producing a bi-directional electrical steel sheet having excellent magnetic properties, wherein annealing is performed under reduced pressure using a substance that promotes Mn.

Si (%) + 0.5Mn (%) ≦ 4 (1) Si (%) − 0.5Mn (%) ≧ 1.5 (1)・ ・ (2) Mn (%) ≧ 0.2 ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ (3) (2) Rolling in two directions perpendicular to each other is performed in α + γ two-phase temperature range. The method for producing a bidirectional magnetic steel sheet according to (1), wherein the steel sheet is rolled in one direction within a temperature range of α phase.

(3) As rolling in two directions perpendicular to each other,
2. The production of a bidirectional electrical steel sheet according to (1), wherein rolling is performed in one direction in a two-phase temperature range of α + γ, and rolling is performed in a temperature range of α-phase in a direction orthogonal to the rolling direction. Method.

[0025]

BEST MODE FOR CARRYING OUT THE INVENTION

I. Chemical composition C is required to contain 0.02% or more of C in the material in order to control texture using the γ → α transformation accompanying decarburization. If it is less than 0.02%, all phases may be in α-phase before decarburization, and the transformation cannot be used. When the content of C is increased, not only long time is required for decarburization, but also rolling becomes difficult.
Up to. That is, the content range of C in the material is 0.02 to
0.2%. Note that, from the viewpoint of more stably performing the γ → α transformation and improving the workability and the efficiency at the time of decarburization, the preferable content is 0.04 to 0.08%.

Since the presence of C has an adverse effect on magnetic properties, the smaller the C content after decarburization, the better.
It is desirable to make it 0.005% or less.

Mn has an effect of developing a preferred orientation more effectively by simultaneously removing Mn when forming a texture by decarburization. To do this,
Before annealing, it must be contained at least 0.2%, preferably at least 0.3%.

Si increases the electric resistance and reduces the eddy current loss which forms a part of the iron loss. In addition, the addition of Si has the effect of increasing the temperature at which the α-phase appears due to decarburization.
When the temperature exceeds γ, the γ phase disappears regardless of the temperature when the decarburization is sufficient. For the formation of the {100} plane orientation of the present invention, α
High temperature treatment in the phase is necessary, but if there is enough Si,
It easily becomes α-phase by decarburization. Where Mn is α
Since the temperature at which a phase appears tends to decrease, the lower limit of the amount of Si is regulated by the following equation (2) according to the amount of Mn. On the other hand, Si
Increasing the content makes the steel brittle, increases the deformation resistance, makes rolling difficult, and further reduces the magnetic flux density. Since Mn also increases deformation resistance and makes rolling difficult, the upper limits of the contents of Si and Mn are regulated as in the following equation (1).

Si (%) + 0.5Mn (%) ≦ 4 (1) Si (%) − 0.5Mn (%) ≧ 1.5 (1)・ ・ (2) In addition, impurities that are inevitably mixed deteriorate the workability or magnetic properties, so it is desirable that the impurities be as small as possible.

In addition, Al is often added to steel for the purpose of securing the soundness of the slab at the time of casting or fixing N, although there is no particular restriction, but in the present invention, the magnetic properties deteriorate. Since the formation of nitrides that cause the formation of oxides and the formation of oxides on the surface during decarburization annealing hinder the formation of {100} plane orientation,
It is desirable to make it 03% or less.

II, Rolling Conditions The steel having the above-mentioned chemical composition is subjected to hot rolling and cold rolling to finish to a predetermined sheet thickness. At the time of the rolling, orthogonal rolling is performed. The steel material to be subjected to hot rolling may be a slab obtained by slab rolling of an ingot, a slab obtained by continuous casting, or a thin slab slab developed in recent years. Here, hot rolling refers to rolling in the γ + α phase, and cold rolling refers to rolling in the α phase. C, Si,
When the contents of Mn and Mn are within the range defined by the above-mentioned present invention, the temperature is generally γ + α phase at a temperature of approximately 850 ° C. or higher applied to general hot rolling, and α = α phase at a temperature lower than this.
One phase.

In order to obtain a cubic orientation of {100} <001>,
In both the rolling direction and the width direction, it is necessary to perform orthogonal rolling with a rolling reduction of 30% or more, preferably 40% or more. Orthogonal rolling is generally performed at the stage of cold rolling, and sufficient effects can be obtained even if the cold orthogonal rolling is applied to steel having a chemical composition defined in the present invention. However, by carrying out the following rolling method, a still more remarkable effect is obtained, and furthermore, the production of a long steel plate can be facilitated.

(A) After orthogonal rolling is performed in the hot rolling stage, cold rolling is performed in the rolling direction, that is, in one direction, to finish to a required thickness. In the orthogonal rolling in the hot rolling, the rolling order does not matter as long as the total rolling reduction in each of the two directions is 30% or more.
Rolling in both directions may be performed, or rolling in both directions may be appropriately combined, and rolling may be performed several times by reducing the rolling. Further, it is preferable that the rolling reductions in both directions are equal, but it is not always necessary that they be the same.

In the case where rolling is performed a plurality of times while changing the direction,
The total rolling reduction in one direction is the ratio of the total thickness reduced in the direction from the start of rolling to the final pass to the rolling start thickness.

(B) After hot rolling, the steel sheet is subjected to cold rolling in the width direction. Also in this case, the total rolling reduction in each direction is 30% or more.

If the total rolling reduction in each direction is less than 30%, a sufficient {100} <001> orientation cannot be obtained, and in order to more reliably obtain this cubic crystal orientation, a reduction of 40% or more is desirable. . In any of the rolling methods (a) and (b), intermediate annealing may be performed before cold rolling or during cold rolling in order to facilitate rolling. Although the temperature of the intermediate annealing is not particularly defined, it is sufficient that the necessary softening is obtained, and the temperature range of the α + γ phase exceeding 850 ° C. may be used for shortening the time.

III, Final Annealing After orthogonal rolling, a substance that promotes decarburization, or decarburization and Mn removal
An annealing separator containing a substance that promotes both is sandwiched between steel sheets, and in the case of a long steel strip, wound in a coil shape,
In the case of a cut plate, they are laminated and annealed under a vacuum or reduced pressure of 10 Torr or less. Substances that promote decarburization are SiO ₂ , C
r ₂ O ₃ , TiO ₂ , FeO, V ₂ O ₃ , V ₂ O ₅ , V
Oxides such as O.

The conventional method of decarburizing an ultra-low carbon steel sheet or an electromagnetic steel sheet by annealing is such that hydrogen adjusted so as to be reducing for Fe and oxidizing for C in steel is used. Annealing is performed in a wet atmosphere. In other words, if schematically described, decarburization proceeds by the following reaction.

C (solid phase) + H ₂ O (gas phase) → CO (gas phase) + H ₂ (gas phase) In this case, C is oxidized to CO and decarburization proceeds, and Si and Mn are also oxidized. You. C has a high diffusion rate in steel and is easily eliminated, but Si and Mn form oxides and deposit on the steel sheet surface. The oxide on the surface changes the energy state of the steel sheet surface and inhibits the {100} plane orientation from being developed by the surface energy of the α phase in the surface layer.

On the other hand, in the present invention, when the oxide is brought into contact with the surface of the steel sheet and heated to a high temperature under reduced pressure, for example, when the oxide is SiO ₂ , the decarburization proceeds by the following reaction. Conceivable.

C (solid phase) + SiO ₂ (solid phase) → CO (gas phase) + SiO (solid phase) In this case, both C and O (depending on SiO ₂ ) involved in the reaction are solid phases, and CO Since it is in the gas phase, by reducing the pressure, CO as a reaction product is strongly removed, and decarburization is promoted. Moreover, Si and Mn are contained in the gas phase.
Since there is no O (H ₂ O) for oxidizing the oxide, these oxides do not occur on the surface.

In the above-described decarburization at a high temperature under reduced pressure,
At the same time, the removal of Mn by sublimation of Mn in the steel proceeds. The removal of Mn is promoted by the annealing separator, and substances having the effect are TiO ₂ , Ti ₂ O ₃ , ZrO _{2 and the} like. These are considered to have the effect of absorbing sublimed Mn and promoting the removal of Mn by reducing the vapor pressure of Mn near the steel sheet surface. TiO ₂ is also a substance that promotes decarburization. If an annealing separator mainly containing TiO ₂ is used, both decarburization and Mn removal can be promoted.

As the annealing separating agent, a powdery material may be applied to a steel plate, a fibrous material thereof, a sheet-like material composed of fibers, or a powder mixed with these fibers or sheets. It may be something. The oxides may be used alone or as a mixture of two or more. Further, as long as the effect is not significantly reduced, Al ₂ O ₃
A material that is not directly related to the reaction, such as a more stable oxide such as BN and SiC, may be mixed.

When heating and decarburizing by contacting the above annealing separator, the pressure is reduced or reduced to 10 Torr or less. This is because at pressures above 10 Torr, the C
This is because O is not easily removed from the surface of the steel sheet, and the progress of the reaction is significantly slowed down, and furthermore, the sublimation of Mn is suppressed and de-Mn is less likely to occur. Even if it is less than 10 Torr, it may not be possible to decarburize it depending on the composition of the steel. Note that the lower the lower limit of the pressure is, the better the degree of vacuum is, that is, the higher it is. However, there is naturally a limit for industrial implementation.

The annealing for decarburization under reduced pressure using an annealing separating agent may be performed if a layer of recrystallized grains having a {100} <001> orientation of several μm or more is formed on the surface of the steel sheet. Thereafter, the annealing under reduced pressure may be continued as it is until decarburization is completed over the entire thickness, but decarburization may be performed at a higher pressure in a humid atmosphere containing hydrogen, or at normal pressure. .

The decarburizing annealing temperature is in the α + γ phase region of 850 ° C. or higher, and is converted to α one phase by the transformation accompanying decarburization. Higher temperatures may be used as long as they are decarburized to α phase,
Temperatures above 1300 ° C. are difficult to achieve industrially. The temperature at which the {100} <001> orientation can be formed most effectively is 10
00-1200 ° C. The decarburization after the layer of the recrystallized grains having the {100} <001> orientation is formed on the surface of the steel sheet may not be at the high temperature as described above.

The soaking time for annealing is in the range of 30 minutes to 100 hours. In less than 30 minutes, decarburization and Mn removal are insufficient, and the development of recrystallized grains of {100} <001> orientation on the surface is insufficient,
Keeping it for more than 100 hours will saturate the effect and only waste energy.

The annealing for flattening the steel sheet, the insulating coating on the surface, and the like may be the same as those conventionally used for non-oriented electrical steel sheets and oriented electrical steel sheets. Their influence on the magnetic properties of electrical steel sheets is not significant.

[0049]

【Example】

Example 1 Steel having a chemical composition obtained by vacuum melting and casting as shown in Table 1 was hot forged into a slab having a thickness of 80 mm. 1200 ℃
After heating, rolled at a reduction of 50% to a thickness of 40 mm,
Then rotate by 90 ° and continue hot rolling, finishing temperature 880
The thickness was 4 mm at ℃. After pickling and descaling, cold-roll in the same direction as the final hot rolling to a thickness of 1 mm,
0.35m after cold annealing in the same direction after intermediate annealing of min
m thickness. For comparison, hot forging of the same steel 8
A 0 mm thick slab was heated to 1200 ° C and hot rolled in the same direction to a 4 mm thickness. Similarly, a 0.35 mm thick steel sheet was cold rolled, intermediately annealed, and cold rolled.

[0050]

[Table 1]

From these rolled steel sheets, a width of 250 mm and a length of
Cut out 600mm plate pieces, and as an annealing separator between each plate piece
48% by weight Al ₂ O ₃ -51% by weight SiO ₂ fibrous material having a density of 0.02 g / cm ² , and a TiO ₂ powder as a Mn removal accelerator are sandwiched at a density of 0.004 g / cm ² and laminated. And evacuating to 10 ^-3 Torr for 50 hours at 950 ° C, or
Annealing was performed at 1050 ° C. for 12 hours. The carbon content of each piece after annealing was 0.0025% or less.

A test piece having a width of 30 mm and a length of 100 mm was sampled from each of the annealed strips in two directions, a rolling direction and a width direction orthogonal thereto, and the length of the test piece was measured by a single-plate magnetic property measuring apparatus. The magnetization characteristics in the directions were measured. The integrated intensity ratio of the {200} plane was measured by X-ray diffraction.

Table 2 shows the test conditions and the characteristics of the obtained steel sheet. Although the integrated strength ratio of the {200} plane is almost the same as that of the steel sheet obtained by normal unidirectional rolling, the steel sheet manufactured by the method of the present invention has a rolling direction and a width direction. It can be seen that the magnetic properties of the sample are more excellent. In other words, depending on the specific annealing separator and annealing conditions, the {200} plane orientation can be developed. However, if orthogonal rolling is performed during rolling, the magnetic properties in the length direction of the rolling and its perpendicular direction can be improved. You can do it. This is due to the development of the {100} <001> cubic orientation.

[0054]

[Table 2]

Example 2 A steel slab having a thickness of 80 mm was hot forged using steel D shown in Table 1 and heated to 1200 ° C.
It was hot rolled to a thickness of 3 mm. After pickling descaling, 90
゜ Rotate to perform cold rolling in the width direction of hot rolling,
The thickness was 0.35 mm. 250mm wide from these rolled steel sheets,
A plate piece having a length of 600 mm was cut out, laminated under an annealing separator in the same manner and under the same conditions as in Example 1 described above, and annealed. However, annealing temperature and time are 1050 ℃, 12h
And

After annealing, test pieces having a width of 30 mm and a length of 100 mm were sampled in two directions, ie, the rolling direction of the sheet piece and the width direction orthogonal thereto, and were measured in the longitudinal direction of the test piece by a single sheet magnetic property measuring apparatus. The magnetization characteristics were measured. In addition, {20
The integrated intensity ratio of the {0} plane was measured.

The results are shown in Table 3. Compared with the results of Test No. 4 or 10 shown in Table 2, the difference in the characteristics in the rolling direction and the width direction is small, and both directions show excellent magnetic characteristics. .

[0058]

[Table 3]

[0059]

According to the method of the present invention, it is possible to easily obtain an electrical steel sheet having particularly excellent magnetic properties in two directions, ie, a rolling direction and a direction perpendicular thereto. Such an electromagnetic steel sheet is most suitable for applications requiring excellent magnetic properties in two orthogonal directions at the same time, such as an EI core and an L core of a small transformer. And high efficiency can be achieved.

Claims (3)

[Claims] C. 0.02 to 0.2% of Si and M by weight%.
A steel having a content of n that satisfies the following formula is used to roll a steel sheet obtained by rolling in two directions perpendicular to each other to obtain a material that promotes decarburization as an annealing separator or a material that promotes decarburization and a material that promotes decarburization. A method for producing a bi-directional electrical steel sheet having excellent magnetic properties, wherein annealing is performed under reduced pressure by using a substance that promotes heat treatment. Si (%) + 0.5Mn (%) ≦ 4 ・ ・ ・ (1) Si (%) − 0.5Mn (%) ≧ 1.5 ・ ・ ・ ( 2) Mn (%) ≧ 0.2 (3) 2. The two-way electromagnetic device according to claim 1, wherein rolling in two directions perpendicular to each other is performed in a two-phase temperature range of α + γ, and then rolling is performed in one direction in a temperature range of α-phase. Steel plate manufacturing method. 3. The rolling in two directions perpendicular to each other, α +
2. The method for producing a bidirectional magnetic steel sheet according to claim 1, wherein rolling is performed in one direction in a two-phase temperature range of [gamma], and rolling is performed in a [alpha] temperature range in a direction orthogonal to the rolling direction.