JPH05258936A - Electromagnetic foil in excellent roll shape and manufacturing method thereof - Google Patents

Abstract

PURPOSE:To manufacture the title electromagnetic foil in excellent roll shape by a method wherein a unidirectional electromagnetic steel plate in specific crystalline particle diameter is selected to be cold-rolled without performing the intermediate annealing step. CONSTITUTION:A unidirectional electromagnetic steel plate (magnetic flux density Bs/Bs>0.9, crystalline particle diameter: exceeding 20mm in rolling direction, rolling rectangular direction exceeding 400mm) containing 8wt.% >=Si, 0.1% of Mn, 0.001% of C, 0.002% of N. 0.002% of Al, 0.001% of S and the rest of Fe substantially and having a level of integration in {110} <001> direction is pickled to remove a glass film. Later, the steel plate is rolled by a once cold-rolling to attain the final thickness not exceeding 150mum. At this time, the steepness of the final plate thickness does not exceed 1.2%. Through these procedures, the title electromagnetic foil can be extremely thinned without correcting the shape thereof by intermediate annealing step.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetic foil used for a transformer or an inductor in an energy conversion system based on electromagnetic induction in the field of electronic industrial equipment, and a method for manufacturing the same.

[0002]

2. Description of the Related Art Up to now, when an attempt was made to manufacture a rolled foil using a magnetic steel sheet having a high degree of {110} <001> orientation integration as a starting material, the average crystal grain size of the starting material was very large, about 30 mm, so that the crystal The difference in the slip system due to the slight deviation of the orientation became noticeable in the rolled shape, and rolling was impossible.

Therefore, a conventional electromagnetic foil has an average crystal grain size of 2
Rolled foil is made from a magnetic steel sheet having a small degree of 0110 mm and a low degree of {110} <001> orientation integration. However, in the case of rolling with a plate thickness of 50 μm or less, intermediate annealing was necessary.

[0004]

The average grain size of the conventional rolled foil is as small as about 20 mm, but {110} <001>
Since the starting material is a magnetic steel sheet with a low degree of orientation integration, cold rolling causes air pockets in the foil strip due to the difference in the slip system. This rolling shape defect requires not only an intermediate annealing step in the rolling step, but also subsequent continuous annealing, or when the foil strip is threaded by coating, the foil strip is bent, squeezed, and the coating amount is uneven. It becomes a problem such as a problem.

It is an object of the present invention to provide an electromagnetic foil having an excellent rolled shape, which is manufactured by a single cold rolling method using a magnetic steel sheet having a high degree of {110} <001> orientation integration as a starting material.

[0006]

In order to achieve the above object, the present inventors newly found the following by researching electromagnetic foil used for transformers or inductors of electronic industrial equipment. Si ≦ 8% as starting material,
The balance substantially consists of Fe, has {110} <001> orientation integration, has a magnetic flux density B ₈ /Bs>0.9, and has an average grain size in the rolling direction and the direction perpendicular to the rolling direction, respectively. If you select a grain-oriented electrical steel sheet with a grain size of 20 mm or more and 40 mm or more and cold-roll this material,
An electromagnetic foil having a plate thickness of 10 μm or less and a good rolled shape was obtained without intermediate annealing. As a means for industrially obtaining such a starting material, the present inventors have disclosed, for example, in JP-A-59-2.
The technique disclosed in Japanese Patent No. 15419 is proposed.

Further, Si ≦ 8% as a starting material, the balance being substantially Fe, having {110} <001> orientation integration degree, magnetic flux density B ₈ /Bs>0.9, and average grain size. The diameter is 2 in the rolling direction and 2 in the direction perpendicular to the rolling direction.
Even if a grain-oriented electrical steel sheet having a grain size of 5 mm or less is selected and this material is subjected to cold rolling, an electromagnetic foil having a sheet thickness of 10 μm or less and a good rolled shape can be obtained without intermediate annealing. ..

Further, it was found that by rolling the above-mentioned starting material under the conditions of the plate thickness / work roll diameter ≦ 0.04, a rolled foil having a plate thickness of 10 μm or less and a good rolled shape can be obtained. ..

[0009]

By selecting the starting material as described above, the sheet is rolled to a predetermined thickness by the single cold rolling method without intermediate annealing.

[0010]

【Example】

An embodiment will be described with reference to the drawings. Example 1 By weight, Si: 3.3%, Mn: 0.1%, C: 0.0
01%, N: 0.002%, Al: 0.002%, S:
0.001%, unidirectional electrical steel sheet with the balance being substantially Fe (B ₈ = 1.98T, grain size: rolling direction 45 m
m, 500 mm in the direction perpendicular to the rolling direction, plate thickness: 170 μm) was pickled to remove the glass coating, and then 50 times by the single cold rolling method.
The final plate thickness was μm. Table 1 shows the steepness of the final plate thickness. 2.85 on average for commercial products produced by the prior art
%, The average of the product of the present invention is 0.08%, which shows how excellent the rolled shape is.

[0011]

[Table 1]

Example 2 By weight, Si: 3.3%, Mn: 0.1%, C: 0.0
01%, N: 0.002%, Al: 0.002%, S:
0.001%, unidirectional electrical steel sheet with the balance being substantially Fe (B ₈ = 1.98T, grain size: rolling direction 45 m
m, 500 mm in the direction perpendicular to the rolling direction, plate thickness: 170 μm) was pickled to remove the glass coating, and then 8 μm by the single cold rolling method
The final plate thickness was m. Table 2 shows the steepness of the final plate thickness.
In the conventional material, air pockets were formed in the foil strip during the rolling process, and problems such as narrowing, holes, and breakage occurred, and rolling was impossible.
It can be seen that not only is it possible to roll to a plate thickness of μm, but the average value of the steepness is 1.16%, and the rolled shape is also excellent.

[0013]

[Table 2]

Example 3 By weight, Si: 3.2%, Mn: 0.05%, C: 0.
001%, N: 0.001%, Al: 0.002%,
S: 0.0004%, Sn: 0.05%, the balance being a grain-oriented electrical steel sheet consisting essentially of Fe (B ₈ = 1.928).
T, grain size: rolling direction 25 mm, rolling right angle direction 25 mm,
(Plate thickness: 160 μm) was pickled to remove the glass coating, and then the final plate thickness was 40 μm by a single cold rolling method. Table 3 shows the steepness of the final plate thickness. The average of the present invention products is 1.
12%. Despite the fact that the degree of crystal orientation integration is rather low, the rolled shape has achieved product level. The reason why the rolled shape is good despite the low degree of crystal orientation integration is that the difference in the slip system due to the difference in crystal orientation cancels each other out, and the crystal grain size is small It is considered that the difference in the slip system that occurs is not significant and does not appear.

[0015]

[Table 3]

Example 4 By weight, Si: 3.2%, Mn: 0.05%, C: 0.
001%, N: 0.001%, Al: 0.002%,
S: 0.0004%, Sn: 0.05%, the balance being a grain-oriented electrical steel sheet consisting essentially of Fe (B ₈ = 1.928).
T, grain size: rolling direction 25 mm, rolling right angle direction 25 mm,
(Plate thickness: 160 μm) was pickled to remove the glass coating, and then a single cold rolling method was performed to give a final plate thickness of 15 μm. Table 4 shows the steepness of the final plate thickness. The average of the invention products is 1.
44%. It is clear that even a starting material having a low degree of crystal orientation integration can be made extremely thin by the single cold rolling method by reducing the crystal grain size.

[0017]

[Table 4]

Example 5 By weight, Si: 3.3%, Mn: 0.1%, C: 0.0
01%, N: 0.002%, Al: 0.002%, S:
0.001%, unidirectional electrical steel sheet with the balance being substantially Fe (B ₈ = 1.98T, grain size: rolling direction 45 m
m, rolling right angle direction 500 mm, plate thickness: 170 μm) was pickled to remove the glass film, and then once cold rolled 18
The final plate thickness was μm. Fig. 1 shows the steepness of the final plate thickness and the plate thickness / work roll diameter. Plate thickness / work roll diameter ≦ 0.
It can be seen that in the range of 04, the steepness ≦ 1.5% is achieved. This is because the contact area between the material and the roll in the rolling tool is smaller as the roll diameter is smaller, so that stronger deformation resistance can be given.

[0019]

According to the present invention, the foil can be made extremely thin without performing shape correction by intermediate annealing, which is suitable as an industrial cost-saving manufacturing method. Since the material of the present invention has a good shape, continuous passing becomes easy and the effect of improving productivity is obtained. Further, according to the present invention, it becomes easy to uniformly apply the insulating film and the space factor is increased, which leads to improvement in stability of the magnetic characteristics of the electromagnetic foil and enables precise control of electronic devices. ..

[Brief description of drawings]

FIG. 1 is a diagram showing rolled formability of an electromagnetic foil according to Example 5.

Claims (4)

[Claims] 1. Si ≦ 8%, the balance being substantially Fe, having a {110} <001> orientation integration degree, and a magnetic flux density B
₈ /Bs>0.9, and the average grain size is 20 mm or more and 4 in the rolling direction and the direction perpendicular to the rolling direction, respectively.
Starting from a grain-oriented electrical steel sheet with a grain size of 0 mm or more, the thickness after processing is 150 μm or less, and the steepness ≦ 1.2%
Excellent rolled foil electromagnetic foil. 2. Si ≦ 8%, the balance being substantially Fe and having a {110} <001> orientation integration degree and a magnetic flux density B.
_{8 /} Bs> 0.9, and the plate thickness after processing starting from the grain-oriented electrical steel sheet having an average grain size of 25 mm or less in the rolling direction and the direction perpendicular to the rolling direction, respectively. An electromagnetic foil excellent in rolled shape with a steepness ≤1.5% at 150 μm or less. 3. A method for producing an electromagnetic foil having an excellent rolled shape, which comprises cold rolling the starting material according to claim 1 under the condition of plate thickness / work roll diameter ≦ 0.04. 4. A method for producing an electromagnetic foil having an excellent rolled shape, which comprises cold rolling the starting material according to claim 2 under the condition of plate thickness / work roll diameter ≦ 0.04.