JP7625887B2 - Fe-based soft magnetic amorphous alloy thin plate, laminated iron core and rotating electric machine using same, and manufacturing method of Fe-based soft magnetic amorphous alloy thin plate - Google Patents

Description

The present invention relates to a thin plate of an Fe-based soft magnetic amorphous alloy, a laminated core and a rotating electric machine using the same, and a method for manufacturing the thin plate of an Fe-based soft magnetic amorphous alloy.

Rotating electric machines used as motors for electric vehicles and hybrid electric vehicles are required to operate with high efficiency by reducing losses caused by the high frequency of alternating magnetic flux resulting from high speed rotation in order to ensure output. To date, the efficiency of rotating electric machines has been improved by using inverters, applying rare earth magnets, optimizing structural design, etc., but to achieve even higher efficiency, it is necessary to reduce the iron loss of the laminated iron core used in the magnetic poles. Therefore, there is an increasing demand for the application of low-loss magnetic materials such as Fe-based soft magnetic amorphous alloys and Fe-based nanocrystalline soft magnetic alloys containing fine bcc structure Fe crystalline phases and FeSi crystalline phases and amorphous phases, instead of the electromagnetic steel sheets conventionally used in laminated iron cores.

For example, Fe-Si-B based soft magnetic amorphous alloys are known, and are produced by ultra-rapidly cooling a molten metal adjusted to a specified composition using a method such as single-roll liquid quenching to make it amorphous. METGLAS, Inc.'s METGLAS (registered trademark) 2605HB1M and 2605SA1 and the Fe-Si-B-Cr based 2605SA3 are commercially available.

An Fe-based nanocrystalline soft magnetic alloy is obtained by subjecting an amorphous ribbon obtained in the same manner as the Fe-based soft magnetic amorphous alloy to heat treatment to precipitate (nanocrystallize) an Fe crystalline phase or an FeSi crystalline phase. For example, FINEMET (registered trademark) FT-3M from Hitachi Metals, Ltd., which is an Fe-Si-B-Cu-Nb system, VITROPERM (registered trademark) 800 from VACUUMSCHMELZE GmbH & Co. KG., and NANOPERM (registered trademark) from MAGNETEC Gesellschaft fur Magnettechnologie mbH, which is an Fe-B-Zr-Cu system, are known.

All of these are supplied in the form of strips, ribbons, films, or foils, usually in the form of long ribbons with a thickness of 10 to several tens of micrometers. Such ribbons of Fe-based soft magnetic amorphous alloys and Fe-based nanocrystalline soft magnetic alloys are thinner than electromagnetic steel sheets, making it possible to reduce eddy current loss. In addition, Fe-based soft magnetic amorphous alloys and Fe-based nanocrystalline soft magnetic alloys have smaller hysteresis loss than electromagnetic steel sheets, and laminated cores using these ribbons have the advantage of excellent soft magnetic properties.

On the other hand, Fe-based soft magnetic amorphous alloys, including precursors of Fe-based nanocrystalline soft magnetic alloys, are generally ideal elastic-plastic materials that do not undergo strain hardening, and have large plastic deformability and toughness, but are known to be difficult to elongate under uniaxial stress conditions such as tensile tests. Such Fe-based soft magnetic amorphous alloy ribbons are very hard and have the disadvantage of being less workable than crystalline electromagnetic steel sheets, which is a factor in the lack of progress in their application to laminated iron cores, which require processing of ribbons into a specified shape. For this reason, in addition to punching with a die consisting of a punch and a die using a press device (hereinafter referred to simply as punching and distinguished from other processing techniques), various processing techniques have been considered for obtaining a thin plate of a specified shape from a thin ribbon, such as chemical etching, laser processing, and wire electric discharge processing.

Patent Document 1 describes the punching process of amorphous metal foil. By using a servo press to punch the amorphous metal foil at a predetermined punching speed, the generation of burrs due to plastic deformation is suppressed. Patent Document 2 describes the etching process of a ribbon of amorphous alloy material. A crystallized region is formed in a predetermined shape in advance in the ribbon, and the crystallized region is etched to increase the etching speed. This improves productivity in the etching process.

Japanese Unexamined Patent Publication No. 62-9898 Japanese Unexamined Patent Publication No. 55-145174

Figure 5 shows an example of a thin plate used in a laminated core in a perspective view. In the illustrated example, the thin plate 1 is rectangular, has opposing front and back surfaces 20, and four side surfaces 25 connecting the front and back surfaces 20. The thin plate 1 obtained from the thin strip easily bends, but when placed on a surface plate, the front and back surfaces 20 of the thin plate 1 are substantially flat, and if no plastic deformation such as bending occurs, the shape shown in the figure will be obtained. The front and back surfaces 20 of the thin plate 1 remain planar when the thin strip is made, and the side surfaces 25 are cross-sectional surfaces obtained by processing. Figure 6 is a perspective view showing an example of a laminated core formed by stacking multiple thin plates. In the laminated core 5, several to several thousand thin plates 1 are stacked, and they are fixed between the layers and integrated by means of spot welding, riveting, adhesives, etc.

Figure 15 shows a simplified part of a press machine for explaining the punching process. Figure 16 shows an enlarged perspective view of the state of the side of the thin plate produced by punching. Typically, the side 25 of the thin plate 1 is formed with a shear surface 135 and a fracture surface 138 due to shear stress caused by punching, as well as a sag 131 in the thickness direction of the thin plate 1 and a burr 120 due to plastic deformation. In the punching method, a thin ribbon (not shown) is placed on a die 19 having a punching hole and pressed down, while a punch 18 is lowered from above the punching hole, and the punch 18 is passed through the punching hole of the die 19 at intervals of several μm to 100 μm depending on the thickness of the thin ribbon, and the thin ribbon is sheared between the cutting edge provided on the edge of the tip side of the punch 18 and the cutting edge provided on the edge of the punching hole of the die 19. The thin plate 1 punched out of the thin ribbon by shearing is formed with a burr 120 along the outer periphery of the punch 18 in the thickness direction.

According to the method described in Patent Document 1, the degree of burrs occurring in the thickness direction of a thin plate can be suppressed, but it is inevitable that the height of the burrs will increase due to changes over time such as wear of the die and punch, etc. In the first place, due to the mechanism of punching, it is difficult to eliminate the occurrence of burrs occurring in the thickness direction of a thin plate.
In addition, the etching method does not produce burrs in the thickness direction that appear in thin plates when punching, but it requires multiple processes such as resist coating and etching, which makes it less productive than punching and unsuitable for mass production of thin plates. Laser processing and electric discharge processing are also slower than punching, making them less productive.

Figure 17 shows an enlarged cross section of a laminated core made by stacking thin plates with burrs. The thin plates 1 are stacked with a misalignment in the surface direction via a resin layer 200 that bonds the layers. The burrs 120 that occur on the side of the thin plates 1 protrude from the front and back surfaces 20, and may cause the thin plates 1 to come into contact with each other when stacked, resulting in an electrical short circuit. A short circuit between the thin plates 1 increases eddy current loss and is an obstacle to reducing loss in the laminated core 5. In addition, since the burrs 120 occur on the edges of the thin plates 1, as the number of layers of the thin plates 1 increases, the side sides of the laminated core 5 become thicker and bulkier than the center, which also affects the dimensional accuracy of the laminated core 5. In addition, there are cases where the space factor of the laminated core 5 (the ratio of the volume of the thin plates to the volume of the laminated core) cannot be increased.

The present invention aims to provide a thin sheet of Fe-based soft magnetic amorphous alloy that can easily reduce losses in laminated cores, a laminated core and rotating electric machine using the same, and a method for manufacturing the thin sheet of Fe-based soft magnetic amorphous alloy.

According to one embodiment of the present invention, it is possible to provide a thin plate of an Fe-based soft magnetic amorphous alloy for a laminated iron core, the thin plate having opposing front and back surfaces and side surfaces, a thickness of 10 to 50 μm, the side surfaces having fracture surfaces due to ductile fracture that are inclined in the thickness direction of the thin plate from each of the front and back surfaces, and a V-shape tapered toward the end in a cross section in the thickness direction of the thin plate.

According to one aspect of the present invention, it is preferable that all side surfaces of the thin plate are V-shaped.

According to one aspect of the present invention, the fracture surface is preferably a region extending a distance L of 5 μm or more inward from the end of the V-shape that is the outer edge of the thin plate.

According to another aspect of the present invention, a laminated core can be provided in which thin plates of an Fe-based soft magnetic amorphous alloy are laminated.

According to another aspect of the present invention, a rotating electrical machine can be provided in which a laminated core, in which thin plates of an Fe-based soft magnetic amorphous alloy are stacked and fixed, is used in a stator or rotor.

According to one embodiment of the present invention , a method for manufacturing a thin plate of an Fe-based soft magnetic amorphous alloy can be provided, in which a thin non-metallic ribbon having a thickness of 10 to 150 μm is superimposed on the front and back surfaces of a thin plate of an Fe-based soft magnetic amorphous alloy having a thickness of 10 to 50 μm, and the thin plate of the Fe-based soft magnetic amorphous alloy together with the non-metallic ribbon is cut with a rotary die cutter or a Thomson blade to obtain a thin plate having opposing front and back surfaces and side surfaces, the side surfaces being inclined from each of the front and back surfaces in the thickness direction of the thin plate, and having a V-shaped fracture surface tapered toward the end in a cross section in the thickness direction.

According to one aspect of the present invention, it is preferable that the rotary die cutter or the Thompson blade has a flat cutting edge.

The present invention provides a thin sheet of Fe-based soft magnetic amorphous alloy that can easily reduce losses in laminated cores, a laminated core and a rotating electric machine using the same, and a method for manufacturing the thin sheet of Fe-based soft magnetic amorphous alloy.

1 is an enlarged perspective view of a side surface of a thin plate of an Fe-based soft magnetic amorphous alloy according to an embodiment of the present invention. 1 is a cross-sectional view of a thin plate of an Fe-based soft magnetic amorphous alloy according to an embodiment of the present invention, cut in the thickness direction. 1 is a configuration diagram showing one embodiment of an apparatus for processing a ribbon of an Fe-based soft magnetic amorphous alloy. FIG. 4 is a perspective view showing one embodiment of a die-cut roll used in the processing device of FIG. 3. FIG. 2 is a perspective view showing one embodiment of a thin plate used in a laminated core. 1 is a perspective view showing one embodiment of a laminated core formed by stacking a plurality of thin plates; 1 is a cross-sectional view showing an embodiment of a cross section of a laminated core formed by stacking a plurality of thin plates. FIG. 11 is a perspective view showing another embodiment of a thin plate of an Fe-based soft magnetic amorphous alloy. FIG. 9 is a partially enlarged perspective view of the thin plate of the Fe-based soft magnetic amorphous alloy shown in FIG. 8 . 11 is a perspective view showing another embodiment of a laminated core formed by stacking a plurality of thin plates. FIG. 1 is a schematic diagram showing an embodiment of a rotating electric machine using a laminated core of the present invention; 1 is a laser microscope photograph of the side surfaces of the front and back surfaces of the thin plate of Example 1. 1 is a laser microscope photograph of the side surface of a cross section of a thin plate of Example 1. 1 is a laser microscope photograph of the surface profile of the thin plate of Example 1. FIG. 2 is a simplified cross-sectional view of a part of a press device for punching a thin strip. FIG. 2 is an enlarged perspective view of a side of a thin plate produced by punching. 1 is a cross-sectional view of a laminated core formed by stacking thin plates having burrs.

The following describes in detail an embodiment of the present invention, but the present invention is not limited thereto. In addition, in some or all of the figures, parts that are not necessary for the explanation are omitted, and some parts are illustrated enlarged or reduced to facilitate the explanation. In this specification, a numerical range expressed using "~" means a range that includes the numerical values written before and after "~" as the lower and upper limits. In this specification, the term "process" includes not only an independent process, but also a process that cannot be clearly distinguished from other processes as long as the intended purpose of the process is achieved.

1 shows an enlarged perspective view of a side of a thin plate of an Fe-based soft magnetic amorphous alloy according to one embodiment of the present invention. The thin plate according to one embodiment of the present invention may have the same form as that shown in FIG. 5. The side 25 of the thin plate 1 is a processed cross section of an inclined surface 30 that is inclined from each of the front and back surfaces 20 to the thickness direction of the thin plate 1 (z direction in the drawing). FIG. 2 is a cross section of the thin plate 1 cut in the thickness direction. In the cross section (xz plane) of the thickness direction of the thin plate 1, the side 25 of the thin plate 1 has a V-shape that tapers toward the end. The inclined surface 30 has a fracture surface 85 due to ductile fracture in the range of distance L from the end of the V-shape toward the front and back surfaces 20. Here, ductile fracture is a fracture accompanied by plastic deformation, and according to structural observation of the fracture surface with an electron microscope, fine deformation marks are observed on the fracture surface, and the fracture surface exhibits a different mode from brittle fracture and fatigue fracture. The inclined surfaces are continuous with each of the opposing front and back surfaces 20, so there is no need to stack the front and back surfaces 20 of the thin plate 1 separately to create a laminated core, making it easy to handle.

Most of the inclined surface 30 is a fracture surface 85. Microscopically, the fracture surface 85 is a discontinuous surface composed of surfaces with different inclinations, but macroscopically, it is sufficient that the surface is a surface that moves from the flat front and back surfaces 20 toward the edge of the thin plate and away from the front and back surfaces 20. The side surface 25 includes not only a linearly inclined surface as shown in the cross section of the thickness direction of the thin plate 1, but also a curvedly inclined surface and a wavy (undulating) form. In addition, the form of the inclined surface and the region of the fracture surface 85 between the end of the V-shape and the distance L may be different between the inclined surface continuing from one front and back surface and the inclined surface continuing from the other front and back surface. In addition, the fracture surface may have a vein structure. The vein structure is a structure characteristic of amorphous alloys, and is known to be observed in fracture surfaces caused by tension. The vein structure is considered to be the result of viscous flow deformation caused by localized temperature rise due to insulation.

As described above, in the thin plate 1 formed by punching, the angle between the front and back surfaces 20 and the side surface 25 (fracture surface 138) is an acute angle due to the burr 120 and protrudes toward the front and back surface 20. On the other hand, in the thin plate 1 of the present invention, there is no burr that protrudes toward the front and back surface 20, and the angle between the front and back surface 20 and the side surface 25 (inclined surface 30) is an obtuse angle. A cross section of a laminated core 5 formed by stacking such thin plates 1 is shown in FIG. 7. As shown in the figure, the laminated core 5 can be formed in which the increase in eddy current loss due to short circuit is suppressed without interference such as contact between the thin plates 1 due to burrs. In addition, the side surface 25 of the thin plate 1 may have a V-shaped portion only partially, but it is preferable that the V-shaped portion is 50% or more of the circumference of the side surface, and more preferably 80% or more.

In punching, it is difficult to eliminate the occurrence of burrs that protrude in the thickness direction on the edges of a thin plate. Therefore, the inventors have investigated various processing techniques for obtaining a thin plate of a specified shape from a thin ribbon. In the process, they have discovered that it is possible to prevent the occurrence of burrs that protrude in the thickness direction of a thin plate by using a Thomson blade or a rotary die cutter to push through the thin ribbon. By using a combination of a Thomson blade and a receiving stand described below, or a combination of a die cut roll and anvil roll, the thin ribbon is crushed with the blade edge, plastically deformed, and broken, and the resulting thin plate does not have burrs that protrude in the thickness direction that occur in shearing, and the side surface 25 is composed of an inclined surface 30 having a fracture surface 85, and has a tapered V-shape as shown in Figure 1.

In laminated cores, it is preferable that the sheet thickness of the thin plate is thin in order to reduce eddy current loss. On the other hand, as the sheet thickness becomes thinner, the space factor tends to decrease due to the influence of surface roughness, unevenness, etc. For this reason, the thickness of the thin plate (thin ribbon) of the Fe-based soft magnetic amorphous alloy is preferably 10 μm or more and 50 μm or less. More preferably, it is 12 μm or more, and even more preferably, it is 15 μm or more. It is also more preferably 45 μm or less, and even more preferably, it is 40 μm or less. In addition, the aforementioned METGLAS (registered trademark) 2605SA1, etc., which are commercially available, can be used as the thin ribbon of the Fe-based soft magnetic amorphous alloy.

Hereinafter, the manufacturing method of the thin plate of Fe-based soft magnetic amorphous alloy of the present invention will be specifically described with reference to the drawings. FIG. 3 is a configuration diagram of a thin strip processing device including a rotary die cutter. The rotary die cutter is composed of a cylindrical die cut roll 350 and an anvil roll 355, and a sheet-shaped workpiece is inserted between the die cut roll 350 and the anvil roll 355 while rotating them. The workpiece is a laminate of a thin strip of Fe-based soft magnetic amorphous alloy and a thin strip of nonmetallic material, and a thin strip of Fe-based soft magnetic amorphous alloy 301 unwound from a spool 300 is laminated on the front and back sides of the thin strip of Fe-based soft magnetic amorphous alloy 301 unwound from a spool 305, and the thin strip of Fe-based soft magnetic amorphous alloy 301 is sandwiched between the thin strips of nonmetallic material 306 and supplied to the rotary die cutter. FIG. 4 shows an external perspective view of the die cut roll. The surface of the die cut roll 350 is provided with a plurality of push-cutting blades 351. The cutting edge of the cutting blade 351 is flat and has a width of several μm to several tens of μm. The cutting blade 351 presses the workpiece supplied to the rotary die cutter against the surface of the anvil roll 355, crushing and breaking the thin ribbon 301 of the Fe-based soft magnetic amorphous alloy. The thin plate 1 cut out from the workpiece is collected in a container 370 together with non-metallic scraps cut out from the workpiece. The workpiece that has passed through the rotary die cutter is wound up on a spool 360.

The non-metallic thin ribbon 306 functions as a cushioning material and may be, for example, a film-like resin, Japanese paper, or Western paper with a thickness of 10 to 150 μm. The resin is preferably polyethylene, polyvinyl chloride, acrylic, polyethylene terephthalate, or polycarbonate.

Even if the cutting blade of the die-cut roll wears out, no burrs protruding in the thickness direction of the thin plate are generated, so thin plates with V-shaped sides can be stably produced. Furthermore, as the cutting blade wears out, the thin plate is not punched out and part of the end portion tends to remain connected to the thin ribbon of Fe-based soft magnetic amorphous alloy. This state of separation can be used as an indicator of the degree of wear of the cutting blade and the cutting blade can be adjusted, making it easier to maintain and manage the thin ribbon processing equipment. However, the present invention is not limited to this, and a cutting method using a Thomson blade may also be used.

The thin plates obtained through the process of giving a certain shape to the Fe-based soft magnetic amorphous alloy strips can be stacked and integrated with an adhesive or the like. In the stacking process, it is preferable to prepare an alignment jig and a pressure plate according to the shape of the thin plates, stack the desired number of thin plates in the alignment jig, and stack the pressure plates above and below them to integrate the stacking. In bonding between the thin plates of the Fe-based amorphous alloy, it is preferable to form a resin layer uniformly and without unevenness, but if the required adhesive strength is obtained, the resin layer may be formed partially. The resin can be applied to the thin plates of the Fe-based amorphous alloy by dripping or spraying liquid resin onto the thin plates, or by immersing the thin plates in liquid resin. In addition, the thin plates of the Fe-based soft magnetic amorphous alloy may be applied with a coater (coating device) before processing, or the thin plates may be immersed in liquid resin, and then the thin plates may be integrated through a process of giving a shape.

The resins used to bond the thin plates are preferably epoxy or acrylic. Among these, resins with high heat resistance are more preferable.

The thinner the resin layer between the thin plates, the higher the space factor of the laminated core can be, which is preferable. To obtain a high space factor (80% to 98%) while still obtaining the desired adhesive strength, a thickness of approximately 1 μm to 5 μm is preferable, and a thickness in the range of 1 μm to 3 μm is even more preferable. Since no burrs protruding in the thickness direction occur on the edges of the thin plates, the thickness of the resin layer can be made thin, and even if the resin layer is made thin, bulkiness at the edges of the laminated core can be suppressed.

Figure 8 shows a perspective view of another embodiment of a thin plate of an Fe-based soft magnetic amorphous alloy. The thin plate 1 shown in the figure is for a laminated core of a rotating electric machine, and has an annular portion 7 and a plurality of protrusions 6 arranged in rotational symmetry along its inner circumference. Figure 9 is a partially enlarged perspective view of the thin plate. The thin plate 1 shown in the figure has a shape with a plurality of side surfaces 25 on the inner diameter side. By manufacturing such a thin plate 1 by the same means as the thin plate shown in Figure 5, no burrs protruding in the thickness direction are generated at the edge of the thin plate 1, and the side surfaces 25 of the thin plate 1 can be inclined surfaces inclined in the thickness direction of the thin plate 1 from each of the front and back surfaces 20 as shown in Figure 1, and can be formed into a V-shape tapered toward the end. There is no particular restriction on the shape of the thin plate in the present invention, and it can be formed into various shapes.

Figure 10 shows a perspective view of a laminated core constructed by stacking thin plates of an Fe-based soft magnetic amorphous alloy. The laminated core 10 shown is used as the stator of a rotating electric machine, with hundreds to thousands of thin plates 1 stacked on top of each other. The annular portion 7 is used as the back yoke of the stator, and the protruding portions 6 become teeth. The obtained laminated core 10 can also be a laminated core in which the increase in eddy current loss due to short circuits between the thin plates 1 is suppressed.

Figure 11 is a schematic diagram showing an example of a rotating electric machine using the laminated core 10 of the present invention. As shown in Figure 11, in the rotating electric machine 280 of the present invention, a rotor is provided on the inner diameter side of the stator (laminated core) 10 via an air gap. A plurality of permanent magnets 290 are arranged on the outer periphery of the rotor. The permanent magnets 290 are magnetized so that the side facing the stator 10 is a north pole or a south pole, and are arranged at equal angles so that the polarity of adjacent permanent magnets 290 is alternately reversed. Note that in the embodiment shown in Figure 11, the rotor has eight poles, but the number of magnetic poles is not limited to this.

The teeth 6 of the stator 10 are provided with stator windings 260, and a three-phase AC current based on the position of the rotor's magnetic poles is supplied to the stator windings 260, causing the stator to generate a rotating magnetic field. The rotating electric machine operates as a rotating motor due to the rotor's permanent magnets 260 and the rotating magnetic field. In the present invention, a rotating electric machine that can operate with high efficiency can be realized by using a laminated iron core for the stator, which is made of a thin plate of an Fe-based soft magnetic amorphous alloy that is as thin as 10 to 50 μm and has no burrs in the thickness direction.

Hitachi Metals, Ltd.'s Metglas (registered trademark) 2605SA1 was prepared as a ribbon of Fe-based soft magnetic amorphous alloy. The ribbon was long, with thicknesses of 25 μm and 32 μm and a width of 30 mm. The Fe-based soft magnetic amorphous alloy ribbon was broken using a Thomson blade or die-cut roll to produce a thin plate with the shape shown in Figure 8. The outer dimensions of the thin plate were an outer diameter of 22 mm and an inner diameter of 10 mm.

Example 1
The above-mentioned rotary die cutter was used to cut the ribbon of the Fe-based soft magnetic amorphous alloy into a thin plate. The ribbon of the Fe-based soft magnetic amorphous alloy with a thickness of 25 μm was sandwiched between a polyethylene film with a thickness of 13 μm as a buffer material, and the anvil roll and the die cut roll were brought close to each other to pass the workpiece through the ribbon to produce a thin plate. The cutting edge of the die cut roll's press blade was flat with a width of 15 to 30 μm, and the cutting edge angle was 30°.

Example 2
A thin plate was produced in the same manner as in Example 1, except that a thin ribbon of an Fe-based soft magnetic amorphous alloy having a thickness of 32 μm was used.

Example 3
A thin strip of Fe-based soft magnetic amorphous alloy with a thickness of 25 μm was broken by a Thomson blade to produce a thin plate. The cutting device to which the Thomson blade is attached has a drive mechanism for reciprocating the Thomson blade up and down, and a receiving stand with a flat cutting surface on which the thin strip is placed, and can break the thin plate by moving the Thomson blade toward the cutting surface. The thin strip of Fe-based soft magnetic amorphous alloy was used as a workpiece sandwiched between 100 μm thick polyethylene films as a buffer material, and a pressure of 150 N was applied with the Thomson blade to break the thin strip to produce a thin plate. The cutting edge of the Thomson blade is also flat with a width of 20 μm, and the cutting edge angle is 45°.

The side of the thin plate obtained in Examples 1 to 3 was observed from the front and back sides with a Keyence laser microscope VK-X1000. FIG. 12 shows a laser microscope photograph of the front and back side of the thin plate of Example 1. Each thin plate was cut, embedded in resin, and the side of the cut surface was exposed by polishing and observed. FIG. 13 shows a laser microscope photograph of the side of the cross section of the thin plate of Example 1. From the obtained observation photographs, each side had an inclined surface continuing from the front and back sides, the entire inclined surface was composed of a fracture surface due to ductile fracture, and the cross section had a tapered V-shape. In addition, no burrs protruding in the thickness direction caused by shear processing were confirmed in any of them. In the observation of the front and back sides of the thin plate, the distance L from the end of the V-shape on the side of the fracture surface was measured, and the minimum and maximum distances are shown in Table 1 as the fracture surface distance L.

The thin plate of the Fe-based soft magnetic amorphous alloy of the present invention had a fracture surface in a region of about 10 to 100 μm on the side, and the cross section became thinner toward the end. The thin plate of Example 1 was observed at a magnification of 50 times using a Keyence VK-X1000 laser microscope, with an evaluation region of 270 μm x 202 μm including the front and back surfaces and the inclined surface. Figure 14 shows the surface profile of the thin plate. No burrs protruding in the thickness direction were confirmed at the corners formed by the front and back surfaces 20 and the inclined surface 30. This shows that a laminated core made of laminated thin plates according to the present invention is less likely to have an electrical short circuit between layers, and loss in the laminated core can be easily reduced.

1 Fe-based soft magnetic amorphous alloy thin plate 5, 10 Laminated iron core 6 Convex portion 7 Ring portion 18 Punch 19 Die 20 Front and back surfaces of thin plate 25 Side surface of thin plate 30 Inclined surface of thin plate 85 Fracture surface due to ductile fracture 120 Burr 131 Sagging 135 Shear surface 138 Fracture surface 200 Resin layer 260 Stator winding 280 Rotating electric machine 290 Permanent magnet 300 Spool 301 around which a thin ribbon of Fe-based soft magnetic amorphous alloy is wound Fe-based soft magnetic amorphous alloy thin ribbon 305 Spool 306 around which a thin ribbon of nonmetallic material is wound Nonmetallic ribbon 350 Die cut roll 351 Press cutting blade 355 Anvil roll 360 Spool 370 around which a thin ribbon of Fe-based soft magnetic amorphous alloy is wound after processing Container for recovering processed thin plate

Claims (7)

A thin sheet of an Fe-based soft magnetic amorphous alloy for a laminated core,
The thin plate has a front, back and side surface opposite to each other and a thickness of 10 to 50 μm;
The side surface has a fracture surface due to ductile fracture inclined from each of the front and back sides with respect to the thickness direction of the thin plate,
A thin plate of an Fe-based soft magnetic amorphous alloy, which has a V-shape tapered toward one end in a cross section in the thickness direction of the thin plate. A thin plate of the Fe-based soft magnetic amorphous alloy according to claim 1 ,
A thin plate of an Fe-based soft magnetic amorphous alloy, all sides of the thin plate being V-shaped. A thin plate of the Fe-based soft magnetic amorphous alloy according to claim 1 or 2 ,
A thin plate of an Fe-based soft magnetic amorphous alloy, wherein a region extending from an end of a V-shape that is an outer edge of the thin plate to an inner side by a distance L of 5 μm or more is a fracture surface. A laminated core, comprising thin plates of the Fe-based soft magnetic amorphous alloy according to any one of claims 1 to 3 stacked together. A rotating electrical machine using the laminated core according to claim 4 in a stator or rotor. A nonmetallic ribbon having a thickness of 10 to 150 μm is laid on the front and back surfaces of a ribbon of an Fe-based soft magnetic amorphous alloy having a thickness of 10 to 50 μm,
The Fe-based soft magnetic amorphous alloy ribbon is cut together with a nonmetallic ribbon by a rotary die cutter or a Thomson blade.
Obtaining a thin plate having a front and back surface and a side surface, the side surface being inclined from each of the front and back surface sides in the thickness direction of the thin plate, and a V-shaped fracture surface tapered toward an end portion in a cross section in the thickness direction.
A method for manufacturing a thin plate of an Fe-based soft magnetic amorphous alloy . 7. The method for producing a thin plate of an Fe-based soft magnetic amorphous alloy according to claim 6, wherein the cutting edge of the rotary die cutter or the Thomson blade is flattened.

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