JPS629898A - Method of machining amorphous metallic foil - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (a) Purpose of the Invention [Field of Industrial Application] The present invention relates to a processing method for punching an amorphous metal foil such as an amorphous foil.

Amorphous metal foils such as amorphous foils are used in magnetic heads of magnetic recording devices.

[Prior Art] Conventionally, methods for forming amorphous metal foil such as amorphous foil include using a slitter, using a press, or etching.

[Problems to be Solved by the Invention] However, when using a slitter or a press, there is a problem in that the cut end of the amorphous workpiece material is crystallized by heat, and the cut end is likely to have paris. Because the plate was relatively thin, setting the clearance for the die set required skill. Furthermore, the etching method has the problem that it is difficult to obtain fine dimensional accuracy and that commercial production is impossible.

This invention has been made in view of the above circumstances, and is a method for processing amorphous metals such as amorphous foil, which suppresses crystallization of the cut end of the workpiece material and prevents the generation of paris. It is an object of the present invention to provide a method for processing amorphous metal foil that is easy to operate and allows for mass production.

(c) Structure of the invention [Means for solving the problem] Corresponding to this object, the method for processing an amorphous metal foil of the present invention is to punch an amorphous metal foil at a punching speed of 1 m/s or more. It is characterized by processing.

Hereinafter, details of the present invention will be explained with reference to the drawings showing one embodiment.

First, a press apparatus used to carry out the method of processing an amorphous metal foil of the present invention will be described.

In FIG. 1, 1 is a press device. Press device 1
is equipped with a punch 2 and a die 3. punch 2 and die 3
work together to press-form the workpiece 4. What is considered here as the workpiece 4 is an amorphous metal foil such as an amorphous foil.

The punch 2 is attached to a punch holder 5 and is movable relative to the frame 6.

An electromagnetic coil 7 is provided at a fixed position facing the upper end surface of the punch holder 5. The wire of electromagnetic coil 7 is punched 2
is wound in a plane perpendicular to the direction of displacement.

A pressure receiving plate 8 is provided between the electromagnetic coil 7 and the punch holder 5. The pressure receiving plate 8 is a plate-shaped body made of a conductive metal such as copper, and is fixed to the punch holder 5.

The die 3 is supported on the bolster 11 and is in a fixed position.

[Function] In the processing method of the present invention, the workpiece 4 is pressed in the press apparatus configured as described above. In this case, first, the workpiece 4 is set on the die 3.

Next, electrical energy is stored in a capacitor (not shown),
When a large impact current is passed through the electromagnetic coil 7, the pressure receiving plate 8 is displaced and the punch holder 5 is also displaced due to the repulsive force generated between the pressure receiving plate 8 induced by the induced current and the electromagnetic coil 7. is driven to apply shearing to the workpiece 4.

[Example] 260 is often used as a workpiece material for transformer cores.
No. 58-2 was punched using a conventional mechanical press and an electromagnetic press using a high-speed punching device, and the effects of clearance, shear rate, etc. on the cut surface properties were evaluated categorically.

A. Experimental equipment and method The die (a) used in the mechanical press had a punching speed range of 0.
．． 06~0.22n+/s (210~7゛00SpI
ll), the clearance was set to 1, 1, 5, 2 and 5 μm on one side by changing the punch diameter with the die diameter at 5a+m. Note that 40 kg was applied as a temporary pressing force.

The die (b) made by electromagnetic press has a punching speed of 0 and 20
~15 m/s, and the clearance was 5 μm. The materials used for the punch and die were carbide (V5) in (a) and 5KD11 in (b).

B. Experimental results and discussion B-1 Work material Punched material 2605S- with plate thickness 28μm and width 27I1m
Table 1 shows the characteristic values of No. 2. The measured hardness is Hv=724
The Young's modulus obtained from the tensile test is 7198Kg.
/lllI2, and the tensile strength was 181 K'j/mm2. Figure 2 shows a diffraction image when the sample surface was irradiated with X-rays. No crystallization is observed at 400°C and occurs at 600°C. Although no crystallization is observed in Figure 2 (b), considering the fact that the fracture surface obtained by the tensile test has a thin cell-like fracture surface and that the sample falls apart at the time of fracture, the material seems to have become brittle.

B-2 Influence of punching speed Punching with a mechanical press with a clearance of 2 μm,
The results of measuring the area ratio are shown in Figure 3.

(a) shows the cut surface of the product, and as the punching speed increases, the shear surface increases and the fracture surface decreases. On the other hand, the opposite trend is occurring on the waste side (b). This is thought to be caused by the fact that shearing of the amorphous material is hardly accompanied by plastic deformation, the location of crack occurrence, the temporary press 11, etc. Sagging decreases as speed increases on the product side, but increases on the handling side. This depends on how easily deformed patterns occur. Figure 4 shows the speed dependence of Paris height.

With the increase in drawing speed, the speed of pari height decreases significantly.

The punching speed can be further increased by using electromagnetic force. Therefore, assuming the capacitor capacity is constant,
The extraction was performed by controlling the speed using the charging energy. According to this method, vein-like tissue is produced. This is because the clearance was as large as 5 μm, and it is thought that the crack was adiabatically deformed under the local temperature rise, resulting in the breakage. FIG. 5 shows the results of optically measuring the speed of the punch, and shows the speed before and after colliding with the workpiece. The weight of the punch including the pressure receiving plate is 436 g, and the energy required for punching can be estimated from the speed change. FIG. 6 shows the area ratio occupied by the vein-like tissue on the cut surface. As the charging energy increases and the shear rate increases, the veining also increases. This is because the temperature rise in the sheared portion increases as the extraction speed increases. 7th
The figure shows the dependence of Paris on the extraction speed. Again, with increasing speed, Paris is decreasing exponentially.

Figure 8 shows the shape of the cut surface measured after being embedded in resin.

A good cut surface is obtained by high-speed shearing.

B-3 Influence of Clearance Figure 9(a) shows the changes in the area ratio of the shear plane and fracture plane due to the difference in clearance. When punching at 0.06 m/s, the maximum shear plane was achieved at a clearance of 5.4%. Furthermore, as the shear rate increased, the clearance that produced the maximum shear surface tended to increase. FIG. 9(b) shows the area ratio on the waste side, and the maximum shear surface occurs at a clearance around 7.1%. Figure 10 shows the measurement results of the height of cracks produced on the product. The height of Paris increases with increasing clearance and decreases with increasing shear rate, as shown in the previous section.

B-4 Influence of the number of punches Figure 11 shows the change in the properties of the cut surface due to an increase in the number of punches. After punching both the product and the blanks 1,000 to 2,000 times, the shear surface reaches its maximum.

This seems to be due to the shaving effect caused by wear of the punch cutting edge.

After punching more than 4000 times, the shear surface decreases and the fracture surface increases. FIG. 12 shows the results of measuring changes in Paris height. In order to suppress the burst height to 5 μm or less, the limit is considered to be 2000 to 4000 times even when using a carbide mold. FIG. 13 shows the results of examining the state of wear that causes cracks when punching is performed at high speed. 2 in the diagram
The book curves show the shape of the cutting edge immediately after polishing and after punching 500 times, respectively. At low punching speeds (V=0.06 m/s), the wear on the punch side surfaces is significant and decreases as the speed increases. As the clearance increases, side wear also decreases.

Regarding the end face of the punch, the difference in wear depending on these parameters is not clear. Figure 14 shows the shape of the cut surface of the product. As the number of punching increases, the sagging and sag become more severe.

The extent of amorphous crystallization due to temperature increase due to deformation of the crystallized sheared portion of the B-5 cut surface and wear resistance was investigated by electron beam diffraction.

FIG. 15 shows a Debye-Scherrer ring photographed by irradiating an electron beam with a diameter of 10 μm. It can be seen that crystallization on the shear plane is most advanced. Oriented crystals are formed due to the temperature increase caused by friction with the punch side. On the other hand, although a slight amount of crystallization is observed on the fracture surface and vein-like structure, the amount thereof is small.

C0 Conclusion Amorphous foil 26058-2 was punched using a mechanical press and an electromagnetic press, and the effects of speed, clearance, punch wear, etc. on the cut surface were investigated. From these results, it is effective to punch amorphous at high speed with a larger clearance than at low speed, and therefore,
The high-speed punching method of this invention is effective.

In the above description, an electromagnetic press is used as an example of a high-speed punching device, but other high-speed punching devices such as a petroforge machine or any other high-speed punching device can be used.

(c) Effects of the Invention As is clear from the above explanation, the high-speed punching method of the present invention reduces the possibility of crystallization of the cut end of the workpiece during shearing of amorphous metal foil such as amorphous foil. In addition, it is possible to obtain a shearing method that hardly generates flakes, is easy to work with, and can be mass-produced.

[Brief explanation of the drawing]

Figure 1 is a longitudinal cross-sectional view of an electromagnetic press machine, which is a high-speed punching machine, Figure 2 is a graph showing the diffraction image when the surface of the workpiece is irradiated with X-rays, and Figure 3 is a graph showing the area ratio. , Fig. 4 is a graph showing the speed dependence of the par height, Fig. 5 is a graph showing the speed before and after the punch collides with the workpiece,
Figure 6 is a graph showing the area ratio of the vein-like tissue on the cut surface, Figure 7 is a graph showing the dependence of Paris on the extraction speed, Figure 8 is a micrograph showing the shape of the cut surface, and Figure 9 is the clearance. Figure 10 is a graph showing the dependence of Paris on clearance, Figure 11 is a graph showing the number of punches and the shape of the cut surface.
Figure 2 is a graph showing the number of punches and punch height, Figure 13 is an explanatory diagram showing punching speed and punch wear, Figure 14 is a micrograph showing the number of punches and cross-sectional shape, and Figure 15 is electron diffraction. FIG. 2 is an explanatory diagram showing the occurrence of a Debye-Scherrer ring on a cut surface. 1...Press device 2...Punch 3...Die 4...Workpiece material 5...Punch holder 6.
...Frame 7...Electromagnetic coil 8...Pressure plate 9...Urethane spring 11...Bolster Diagram 1 ■ Baso height? (lJm) Menoki? (%) Punch distance V (m/s) v: 0.06m/s
v: 3.53m/s 9th
Figure (0) Product (b) Talented friend ξ scum 7
Clearance/J clearance (Figure 10) Clearance/Thickness ('/, 1 Figure 11 (0) Product (b) ↑3 times XIO' Hit t&!1st Autumn xlo3 1st
Figure 2 Punching and rolling soft x IQ3 Figure 13 80oO times continuous punching Figure 14 1000 times 4000 times 8000 times C/
Word: 5.4'/6 V: 0.06m
/sFigure 15

Claims (1)

[Claims] A method for processing amorphous metal foil, characterized by punching the amorphous metal foil at a punching speed of 1 m/s or more.