JP4016431B2 - Directional silicon steel strip manufacturing method and electrolytic etching apparatus - Google Patents

Description

【００２３】
【発明の効果】
この発明は、鋼帯の表面の２〜10mmピッチで線状溝を連続的に導入する電解エッチングプロセスにおいて、エッジ部と中央部の溝深さの最適化のため鋼帯の幅方向両側外方に遮蔽手段を配置し、センサを用いた鋼帯エッジ検出制御により遮蔽手段を鋼帯の被エッチング面と電極板との間に一定挿入するようにしたから、鋼帯端部の線状溝深さを中央部の溝深さの70％以下に低減できるようになり、次工程以降での破断を防止することができる。
さらには上記マスキング装置を用いて、遮蔽手段の挿入量を一定量に維持するように制御できるため、板の蛇行がおこっても鋼帯エッジ部は常に所定領域にわたってエッチングが抑制でき、最適溝深さを満足できる。その結果、歩留まり低下を招くことなしに線状溝を起点とした鋼帯破断を防止できるようになった。
【図面の簡単な説明】
【図１】鋼帯幅方向端部及び中央部の溝深さえ板破断に及ぼす影響を示すグラフである。
【図２】この発明の電解エッチング装置の一例を示す図である。
【図３】この発明について遮蔽板と鋼帯との重なり代を15mm、50mmに設定したときの鋼帯幅方向の線状溝深さの分布図である。
【符号の説明】
１ けい素鋼帯
２ コンダクターロール
３ 電解槽
４ 電解液
５ 電極
６ 遮蔽板
７ 支持部材
８ 駆動装置
９ 検出手段[0001]
[Industrial application fields]
The present invention relates to a method of manufacturing a grain-oriented electrical steel sheet, and in particular, proposes the results of research and development in the case where magnetic domain subdivision is achieved by performing electrolytic etching on the steel sheet surface to form linear or dotted grooves. It is in.
[0002]
[Prior art]
After hot rolling the silicon-containing steel material, followed by two cold rollings that include one or two intermediate annealings, a local etching process is performed before the final finishing annealing, so that the groove gap A method for subdividing magnetic domains of grain-oriented electrical steel sheets comprising forming grooves of 2 to 10 mm and a groove depth of 5 to 35 μm is known as disclosed in Japanese Patent Laid-Open No. 63-42332. As such an etching method, chemical etching and electrolytic etching are known. However, electrolytic etching is advantageous in that it is easy to control the groove depth by current.
[0003]
In this electrolytic etching, an insulating material such as ink is selectively applied and baked as a masking material (etching mask) on the surface of the steel plate in advance, and then the electrolytic etching is performed to act on the area where the masking material is not formed. In general, the step of forming the groove and then removing the insulating material is performed.
[0004]
[Problems to be solved by the invention]
However, generally oriented silicon steel contains Si: 2.0-4.0%, so it is hard and the plate thickness is relatively thin, 0.15-0.35 mm. In addition, the groove is generally formed over the entire width in the width direction of the steel strip in the form of lines or dots. Therefore, when a necessary amount of linear grooves such as a depth of 5 to 35 μm at a pitch of 2 to 10 mm is introduced on the surface of the steel strip by electrolytic etching, the width direction end portion (hereinafter referred to as an edge portion) of the steel strip in the subsequent process. There is a problem that the steel strip breaks frequently from the linear groove of ( also referred to as) .
[0005]
The present invention advantageously solves the above problems, and a method for producing a directional silicon steel strip in which the etching amount in the width direction of the steel strip is controlled to prevent the steel strip from breaking, and the directional electromagnetic steel. An object of the present invention is to propose an electrolytic etching apparatus suitable for use in the production of a band.
[0006]
[Means for Solving the Problems]
The present invention for solving the above problems
Si: Cold-rolled directional silicon steel material containing 2.0 to 4.0 wt% to finish the final sheet thickness of 0.15 to 0.35 mm, before the final finish annealing, the surface of the steel strip A directional silicon steel sheet is formed by selectively forming an etching mask and then forming a linear or dotted groove on the surface of the steel strip at a groove depth of 5 to 35 μm and a groove pitch of 2 to 10 mm by performing electrolytic etching. In the manufacturing method,
During the electrolytic etching, etching of the width direction end of the steel strip is suppressed, and the groove depth at the width direction end is set to 70% or less of the groove depth at the width direction center. It is a manufacturing method of a directional silicon steel strip.
[0007]
In addition, this invention
An electrolytic etching apparatus having an electrode facing the silicon steel strip in which an etching mask is selectively formed in the internal space of the electrolytic cell, and having a power source that is electrically connected to this electrode and also to the silicon steel strip through an energizing means. Because
An electrolytic etching apparatus characterized in that a shielding means is provided between an electrode and a region up to 15 mm from the width direction end of the silicon steel strip to be subjected to electrolytic etching or a region from the width direction end to 80 mm. .
[0008]
Here, the electrolytic etching apparatus of the present invention has a driving device for moving the shielding means in the width direction of the steel strip and a detection means for detecting the end position of the silicon steel strip. It is more preferable to be able to move in the steel strip width direction based on the steel strip end position data.
[0009]
[Action]
Hereinafter, the elucidation process of the present invention will be described.
The inventors conducted various investigations in order to investigate the cause of the plate breakage, and found that the region where the predetermined groove depth is reached, particularly the distribution in the plate width direction, greatly affects the breakage of the steel strip. It was. Therefore, the relationship between the plate breakage and the groove shape was determined in the following experiment.
[0010]
Masking material (materials: 9 types of silicon steel cold-rolled plates prepared with 3 types of Si content of 2.5 wt%, 3.0 wt% and 3.5% and plate thickness of 3 types of 0.18mm, 0.21mm and 0.30mm) After applying one side of the resist ink), grooves were formed on the surface of the steel sheet by electrolytic etching so that the groove width was 150 μm in the direction perpendicular to the rolling direction (that is, the width direction of the steel sheet) and the groove interval was 5 mm. Regarding the groove depth, in this electrolytic etching, in order to suppress etching of the width direction end portion of the silicon steel plate, by arranging a shielding plate between the width direction end portion and the electrode, this width direction The groove depth was variously changed at the end and the center in the width direction. In addition, the overlap margin of the width direction edge part of a steel plate and a shielding board was made constant with 50 mm per side.
[0011]
With respect to these samples, a 90 ° bending test with a bending radius of 5 mm was performed 20 times to examine the breaking condition of the plate, and the relationship between the edge portion in the width direction and the groove depth at the center portion was obtained. These results are shown in FIG. FIG. 1 shows that in the range of the Si amount and the plate thickness, the dominant factor affecting the plate breakage is the ratio of the groove depth between the plate edge portion and the plate center portion, and this ratio is 0.7 or less. As a result, it became clear that the plate was not broken. This result has been confirmed in the range of Si: 2.5 to 4.0 wt% and plate thickness of 0.15 to 0.35 mm.
[0012]
As described above, according to the present invention, during the electrolytic etching, the etching of the width direction end portion of the steel strip is suppressed, and the groove depth at the width direction end portion is set to 70% or less of the groove depth at the width direction center portion. By doing so, the etching amount of a fixed area | region can be reduced from the width direction edge part of a steel strip. This effect can prevent the plate from breaking.
[0013]
As specific means for suppressing the etching of the steel strip width direction end, a shielding means, that is, a steel strip width direction end masking device, is interposed between the steel strip etching surface and the electrode plate, and between the steel strip and the electrolytic plate. It is possible to partially block the electrolytic current flowing through the steel plate in the width direction end.
[0014]
The overlap allowance between the shielding means and the end portion in the width direction of the steel strip between the electrode and the steel strip is a certain amount, preferably 15 to 80 mm per side. , The overlapping margin is insufficient etching amount reducing effect of less than does the steel strip width direction end portion 15 mm, whereas, the area of reduced error etching amount becomes excessive in the steel strip width direction exceeds 80mm because Because. Note that the region where the etching amount is reduced is a region that is finally trimmed, and therefore, yield and magnetic characteristics are not deteriorated.
[0015]
In order to control the overlap margin to a constant amount, the present invention provides a driving device for moving the shielding means in the steel strip width direction and a detecting means for detecting the end position of the silicon steel strip, and this shielding means. Is advantageously moved in the width direction of the steel strip based on the steel strip end position data from the detecting means.
[0016]
FIG. 2 shows a front view (FIG. 2 (a)) and an AA 'sectional view (FIG. 2 (b)) showing an embodiment of the electrolytic etching apparatus of the present invention. This apparatus is an apparatus that performs electrolytic etching continuously. In the figure, reference numeral 1 denotes a silicon steel strip as a workpiece, 2 is connected to a positive pole of a power source (not shown), and the silicon steel strip 1 is wound to energize. Conductor roll to be used, 3 is an electrolytic cell, 4 is an electrolytic solution filled in the electrolytic cell, and 5 is an electrode disposed opposite to the silicon steel strip 1 conveyed in the electrolytic cell 3. Is connected to the negative pole of a power supply (not shown).
[0017]
In such an electrolytic etching apparatus, a steel strip 1 whose surface is selectively masked with resist ink is wound around a conductor roll 2 connected to the positive pole of a power source, and is charged positively and filled with an electrolytic solution 4. It is guided into the tank 3. On the other hand, since the electrode 5 disposed opposite to the steel strip 1 in the electrolytic cell is connected to the negative pole of the power source, the surface of the steel strip 1 is electrolytically etched into a linear groove shape.
[0018]
In such an electrolytic etching apparatus, as shown in FIG. 1 (b), a shielding plate 6 is inserted between the surface to be etched of the steel strip 1 and the electrode 5 to suppress etching of the end portion in the width direction of the steel strip 1. . The shielding plate 6 is connected to the driving device 8 via the support member 7 and is movable in the steel strip width direction by the operation of the driving device 8. And the end part of the steel strip 1 is detected by the photo sensor provided on the upstream side of the electrolytic cell, for example, the detecting means 9 of the width direction end portion position of the steel strip, and the drive device 8 based on this detection data, Control is performed so that the overlap between the shield plate and the steel strip is always constant.
[0019]
By performing such control, it is possible to stably suppress etching at the end in the width direction of the steel strip 1. In addition, even when the steel strip meanders, it is possible to reliably prevent the etching of the end portion in the width direction of the steel strip, and to reliably prevent the steel strip breakage starting from the linear groove. In addition, such control has an advantage that it can be easily changed when changing the overlap margin, and also when shielding a plurality of types of steel strips having different widths. There is an effect that a desirable overlap margin between the plate and the end in the width direction of the steel strip can be secured.
[0020]
【Example】
Using the electrolytic etching apparatus shown in FIG. 2, a 3% silicon-containing grain-oriented electrical steel sheet having a thickness of 0.20 mm that has been hot-rolled and cold-rolled is supplied with NaCl at a concentration of 300 g / l and a temperature of 50 ° C. Electrolytic etching was performed using a bath. Etching conditions are a direct conduction method in which an electrolyte current constant electrical quantity 300C / dm ^2. The thickness of the masking material (material: resist ink) was 1 μm, and the distance between the electrode and the steel plate was 20 mm.
[0021]
FIG. 3 shows the distribution of linear groove depth in the width direction of the steel strip when the overlap margin between the shield plate and the steel strip is set to 50 mm and 15 mm. The groove depth of the edge part was reduced to 70% or less of the central part. As a result of examining the steel strip breakage starting from the linear groove in the subsequent steps, the steel strip breakage was prevented as shown in Table 1, and good results were obtained. On the other hand, in the case where the etching of the end portion in the width direction of the steel strip according to the present invention was not suppressed, plate breakage occurred.
[0022]
[Table 1]

[0023]
【The invention's effect】
In the electrolytic etching process in which linear grooves are continuously introduced at a pitch of 2 to 10 mm on the surface of the steel strip, the present invention is applied to the outer sides of the steel strip in the width direction in order to optimize the groove depth at the edge portion and the central portion. Since the shielding means is arranged between the etched surface of the steel strip and the electrode plate by steel strip edge detection control using a sensor, the linear groove depth at the end of the steel strip is The thickness can be reduced to 70% or less of the groove depth of the central portion, and breakage in the subsequent steps can be prevented.
Further, since the insertion amount of the shielding means can be controlled to be kept constant by using the masking device, the steel strip edge portion can always suppress the etching over a predetermined region even when the plate meanders, and the optimum groove depth can be controlled. Satisfied. As a result, it has become possible to prevent steel strip breakage starting from the linear groove without causing a decrease in yield.
[Brief description of the drawings]
FIG. 1 is a graph showing the effect of even the groove depth at the end and center of the steel strip in width on the plate fracture.
FIG. 2 is a diagram showing an example of an electrolytic etching apparatus according to the present invention.
FIG. 3 is a distribution diagram of linear groove depth in the width direction of the steel strip when the overlap margin between the shielding plate and the steel strip is set to 15 mm and 50 mm according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Silicon steel strip 2 Conductor roll 3 Electrolysis tank 4 Electrolytic solution 5 Electrode 6 Shielding plate 7 Support member 8 Drive device 9 Detection means

Claims (3)

Si: Cold-rolled directional silicon steel material containing 2.0 to 4.0 wt% to finish the final sheet thickness of 0.15 to 0.35 mm, before the final finish annealing, the surface of the steel strip A directional silicon steel sheet is formed by selectively forming an etching mask and then forming a linear or dotted groove on the surface of the steel strip at a groove depth of 5 to 35 μm and a groove pitch of 2 to 10 mm by performing electrolytic etching. In the manufacturing method,
During the electrolytic etching, etching of the width direction end of the steel strip is suppressed, and the groove depth at the width direction end is set to 70% or less of the groove depth at the width direction center. A method of manufacturing a directional silicon steel strip. An electrolytic etching apparatus having an electrode facing the silicon steel strip in which an etching mask is selectively formed in the internal space of the electrolytic cell, and having a power source that is electrically connected to this electrode and also to the silicon steel strip through an energizing means. Because
An electrolytic etching apparatus characterized in that a shielding means is provided between an electrode and a region up to 15 mm from the width direction end of the silicon steel strip to be subjected to electrolytic etching or a region from the width direction end to 80 mm . A driving device for moving the shielding means in the width direction of the steel strip and a detecting means for detecting the end position of the silicon steel strip, and the shielding means is based on the steel strip end position data from the detecting means. The electrolytic etching apparatus according to claim 2, which is movable in a direction.

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