Method for heat treatment of amorphous alloy ribbons and apparatus for heat treatment of amorphous alloy ribbons

Abstract

Provided is a method for heat-treating an amorphous alloy ribbon that can suppress generation of anisotropy in magnetic properties and can uniformly heat-treat the amorphous alloy ribbon, and a heat-treating apparatus. The method for heat-treating an amorphous alloy ribbon according to the present invention includes the steps of bringing the amorphous alloy ribbon into contact with a heated convex surface and moving it, and pressing the portion of the amorphous alloy ribbon that is in contact with the convex surface against the convex surface from the opposite side of the surface that is in contact and moving it.

Description

Technical Field

[0001] This invention relates to a heat treatment method for amorphous alloy strips and a heat treatment apparatus for amorphous alloy strips. Background Technology

[0002] As a method for adjusting the properties of amorphous alloy strips, a process is known in which the amorphous alloy strip is heated by contacting it with a heated convex surface and moving it. Specifically, a method is known in which the amorphous alloy strip is contacted with a heated roller surface, and while being moved under mechanical constraint, heat treatment is performed by rapid heating and cooling (e.g., Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: WO2011 / 060546 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] According to the method described in Patent Document 1, heat treatment can be performed while suppressing embrittlement. However, to ensure sufficient contact with the roller surface, a large tension needs to be applied to the strip. Furthermore, the strip surface may not be flat, and sometimes some undulations remain, increasing the tension required to ensure sufficient contact between the entire strip surface and the roller. In this case, there is a concern that the orientation of the strip may cause excessive anisotropy in the magnetic properties. The use of strips with high anisotropy in magnetic properties is limited. Moreover, the tension applied to the strip to ensure sufficient contact with the roller is also limited, and there is a risk that the contact state between the strip and the roller may become uneven, leading to uneven heat treatment.

[0008] Therefore, this invention provides a heat treatment method and apparatus for amorphous alloy strips that can suppress the generation of magnetic anisotropy and uniformly heat treat amorphous alloy strips.

[0009] Technical means to solve the problem

[0010] The present invention is a heat treatment method for amorphous alloy strip, comprising the following steps: bringing the amorphous alloy strip into contact with a heated convex surface and moving it, and pressing the portion of the amorphous alloy strip that is in contact with the convex surface against a belt member that can be moved by a roller from the opposite side of the contact surface and moving it.

[0011] Furthermore, it is preferable that the belt component is a metal component.

[0012] Furthermore, it is preferable to heat the component while pressing it down.

[0013] Furthermore, it is preferable to perform the process multiple times by changing the surface of the amorphous alloy strip that the convex surface abuts.

[0014] Furthermore, the amorphous alloy strip is preferably a nanocrystalline soft magnetic material.

[0015] The present invention is a heat treatment apparatus for amorphous alloy strip, which performs heat treatment while moving the amorphous alloy strip, comprising a combination of the following components: a heating section including a convex surface for abutting and heating the amorphous alloy strip; and a pressing section for pressing the abutting portion of the amorphous alloy strip against the convex surface from the opposite side of the abutting surface, wherein the pressing section is a strip member that can be moved via a roller.

[0016] Furthermore, it is preferable that the belt component is a metal component.

[0017] Furthermore, the roller preferably includes a heating mechanism for heating the belt member.

[0018] Furthermore, it is preferable to include multiple such combinations in the travel direction of the amorphous alloy strip, wherein in adjacent combinations, the positional relationship between the heating portion and the strip member relative to the amorphous alloy strip is opposite.

[0019] The effects of the invention

[0020] According to the present invention, for amorphous alloy strips, sufficient thermal contact and heat treatment can be ensured even without applying large tension, thereby enabling the manufacture of amorphous alloy strips in which the generation of magnetic anisotropy is suppressed. Attached Figure Description

[0021] Figure 1 This is a three-dimensional conceptual diagram of a heat treatment machine for amorphous alloy strips, which is the first embodiment of the present invention.

[0022] Figure 2 This is a schematic diagram showing the sequence ((a) to (f)) of the heat treatment method for amorphous alloy strips in the first embodiment of the present invention.

[0023] Figure 3 This is an enlarged schematic diagram of the pressing part and the heating part in the second embodiment of the present invention.

[0024] Figure 4 This is a graph showing the magnetic properties of Example 1 and Comparative Example 1 in the first embodiment of the present invention.

[0025] Figure 5 This is a diagram showing the amorphous alloy strips in Example 2 and Comparative Example 2 of the first embodiment of the present invention.

[0026] Figure 6This is a graph showing the magnetic properties of Example 2 and Comparative Example 2 in the second embodiment of the present invention.

[0027] Figure 7 This is a diagram showing the deformation state of the amorphous alloy strip before and after heat treatment in an embodiment of the present invention.

[0028] [Explanation of Symbols]

[0029] 1: Heat treatment equipment

[0030] 2: Amorphous alloy thin strip

[0031] 3: Base

[0032] 4: Thin strip guide slope

[0033] 5: Braking roller for thin belt tension

[0034] 6a, 6b, 6c: Heated rollers

[0035] 7, 9: Thin strip pressing metal strip

[0036] 8a, 8b, 8c: Thermocouples

[0037] 10: Guide roller

[0038] 11: Thin strip width direction control mechanism Detailed Implementation

[0039] (First Implementation)

[0040] Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

[0041] In the heat treatment apparatus of this embodiment, an amorphous alloy strip is brought into contact with and moved against a heated convex surface. One feature of the heat treatment apparatus is the inclusion of a pressing portion that presses the amorphous alloy strip against the convex surface from the opposite side of the pressing surface. The shape of the pressing amorphous alloy strip is not particularly limited, but it is preferable to use a flexible member that conforms to the shape of the heated convex surface. Here, "pressing surface" means that the amorphous alloy strip is in surface contact with the convex surface.

[0042] Figure 1 This is a perspective view of a heat treatment apparatus 1 for amorphous alloy strips used in this embodiment. The heat treatment apparatus 1 includes a strip guide ramp 4 mounted on a base 3, a strip tension brake roller 5, a strip width direction control mechanism 11, heating rollers 6a, 6b, and 6c, a strip pressing metal strip 7, and thermocouples 8a, 8b, and 8c. Figure 1(Not shown in the figure) An amorphous alloy strip 2 can be disposed between the heating roller 6c and the strip pressing metal strip 7. The strip pressing metal strip 7 is an example of a flexible member, which is a strip member that can move via the roller. From the viewpoints of flexibility, strength and heat resistance, a metal member is preferred for the flexible member (strip member).

[0043] Here, the heating roller 6c is a roller used for heating by direct contact with the amorphous alloy strip. The amorphous alloy strip 2 abuts (contacts) a portion of the outer circumferential surface (a portion of the circumferential region) of the cylindrical heating roller 6c and is heated. Furthermore, the roller 6c itself does not have a drive source and can be driven by the strip pressing against the metal strip 7, thus operating synchronously without a complex mechanism.

[0044] The rollers used to drive the thin strip pressing the metal strip 7 can be either heating roller 6a or heating roller 6b. In this embodiment, the structure is designed so that heating roller 6b has a driving force, causing heating roller 6a to be mechanically driven. This avoids complex control procedures such as electrical synchronization of heating roller 6a or heating roller 6b, and eliminates the need to correct for asynchrony caused by the thermal expansion difference between heating roller 6a and heating roller 6b.

[0045] The thin strip pressing metal strip 7 presses the amorphous alloy thin strip 2 against the heating roller 6c. That is, the thin strip pressing metal strip 7 presses the amorphous alloy thin strip 2 against the convex surface (outer curved surface) of the heating roller 6c from the opposite side of the contact surface. In other words, the heating roller 6a, the heating roller 6b, and the thin strip pressing metal strip 7 constitute the pressing part in the heat treatment apparatus 1.

[0046] Furthermore, the heating roller 6c is an example of a heating section that includes a convex surface for contacting and heating the amorphous alloy strip. Moreover, "convex surface" refers to a surface raised on the side of the amorphous strip, in addition to... Figure 1 In addition to the cylindrical (cylindrical) side surface shown in the example roller, the curved surface that forms part of the component, such as the curved surface of a Japanese fish cake-shaped component, can follow the shape of the amorphous thin strip to ensure sufficient contact.

[0047] The material of the amorphous alloy strip 2 is not particularly limited. For example, it can be used in Fe-based amorphous alloys such as Fe-Si-B and Fe-Si-BC, or as Fe-based nanocrystalline alloys such as Fe-Si-B-Nb-Cu and Fe-Si-B-Nb-Cu-Ni, which are used as nanocrystalline soft magnetic materials. The Fe-based nanocrystalline alloy has a composition in which nanocrystals are crystallized by heat treatment of the amorphous alloy strip.

[0048] The roller constituting the pressing section of the heat treatment apparatus 1 only needs to drive the thin strip pressing metal strip 7 to press the amorphous alloy thin strip 2 against the heating roller 6c, and therefore heating is not always necessary. However, in the heat treatment of amorphous alloy thin strips, it is necessary to raise the temperature of the amorphous alloy thin strip to, for example, 500°C. Therefore, if the temperature increases, the heat loss due to radiation increases. In particular, the small-volume thin strip pressing metal strip 7 has little heat accumulation, so its temperature drops rapidly. Therefore, by equipping the roller constituting the pressing section with a heating roller that includes a heating mechanism, continuous heating can be provided, and the temperature stability of the thin strip pressing metal strip is improved. By using the thin strip pressing metal strip, which is kept at a high temperature, and the roller to clamp the thin strip from both sides, the heat supply rate to the thin strip is increased, rapid heating of the thin strip can be achieved, and the stability of the heat treatment temperature can be expected.

[0049] When the amorphous alloy strip 2 is an Fe-based amorphous alloy, the heating temperature of heating rollers 6a, 6b, and 6c is preferably 350°C or higher and 400°C or lower, respectively; when it is an Fe-based nanocrystalline alloy, etc., the heating temperature is preferably 500°C or higher, respectively.

[0050] The material of the thin strip pressing metal strip 7 is not particularly limited. For example, it is more preferable to use materials with excellent heat resistance, such as heat-resistant stainless steel or nickel-based super heat-resistant alloys.

[0051] The tension roller 5 and the strip width direction control mechanism 11 are used together to prevent the strip from bending. The strip width direction control mechanism 11 functions to prevent the strip in front of the tension roller 5 from shifting laterally, so that the strip enters the center of the tension roller 5. Conversely, in the event of lateral shift (bending) at the position where the heated roller 6c clamps the strip, the tension generated by the tension roller 5 produces a force that restores the strip to the center, thereby suppressing bending.

[0052] Next, using the cross-section representing the heat treatment apparatus 1... Figure 2 The heat treatment method of this embodiment will be described in sequence ((a) to (f)). In the heat treatment method of this embodiment, an amorphous alloy strip is brought into contact with a heated convex surface and moved. At this time, the part of the amorphous alloy strip that is in contact with the convex surface is pressed against the convex surface from the opposite side of the contact surface and moved thereby.

[0053] First, the thin strip pressing metal strip 7 is placed on the heating rollers 6a and 6b, and the heating roller 6c is positioned so that it abuts against the thin strip pressing metal strip 7 from the outside, while tension is applied. Figure 2 (a)). The thin strip pressing metal strip 7 is configured to move via the heating roller 6a and the heating roller 6b.

[0054] Heating rollers 6a, 6b, and 6c are rotated in the direction of the arrows shown in the dotted diagram, and heating rollers 6a and 6b are heated to, for example, 550°C, and heating roller 6c is heated to, for example, 500°C. At this time, the temperatures of heating rollers 6a, 6b, and 6c, as well as the thin strip pressing metal strip 7, are measured and controlled using thermocouples 8a, 8b, and 8c. Figure 2 (b)

[0055] With the strip tension lifted by the brake roller 5 in the direction of the thin arrow in the figure, the amorphous alloy strip 2, which is not shown in the figure, is fed along the strip guide slope 4 in the direction of the black arrow in the figure. Figure 2 (c) A strip tension roller 5 for suppressing strip bending and a strip width direction control mechanism 11 are provided at the entrance of the strip guide ramp 4. The strip tension roller 5 is subjected to a small tension to prevent bending, but if the strip is clamped between the metal strip 7 and the heating roller 6c for heat treatment, the friction generated by the clamps near the entrance counteracts the tension, so no tension is applied to the strip in the subsequent heat treatment zone.

[0056] By using inclined thin-strip guide ramps 4 on the front and back (both sides) of the heating roller 6c, the amorphous alloy thin strip 2 can simultaneously contact and discharge with the thin-strip pressing metal strip 7 and the heating roller 6C. That is, by adjusting the inclination angle of the thin-strip guide ramps 4, the supply and discharge angle of the amorphous alloy thin strip 2 can be set, thereby simultaneously heating and cooling the front and back sides of the amorphous alloy thin strip 2. More preferably, it is arranged on the extension line of the thin-strip guide ramps in a manner consistent with the tangent of the heating roller 6c.

[0057] After the amorphous alloy strip 2 is clamped between the strip pressing metal strip 7 and the heating roller 6c, the strip begins to be automatically wound. Here, the tension of the strip is set by the brake roller 5. Figure 2 (d)

[0058] The amorphous alloy strip 2 abuts against the convex surface of the heating roller 6c and moves. The metal strip 7 is pressed by the strip to press the abutting part of the amorphous alloy strip against the convex surface of the heating roller 6c from the opposite side of the abutting surface and moves. Figure 2 (e)).

[0059] The speed at which the thin strip presses the metal strip 7 is different from the speed of the amorphous alloy thin strip 2, which can cause slippage. Preferably, the thin strip presses the metal strip 7 and the amorphous alloy thin strip 2 move together.

[0060] The amorphous alloy strip 2, passing through the pressing part between the thin strip pressing metal strip 7 and the heating rollers 6a and 6b and the heating roller 6c, is discharged along the thin strip guide slope 4 in the direction of the hollow arrow in the figure. Figure 2(f)). The discharged amorphous alloy strip 2 is wound by a strip winding machine (not shown).

[0061] (Second Implementation)

[0062] Next, the second embodiment of the present invention will be described in detail with reference to the accompanying drawings. Furthermore, the heat treatment apparatus for amorphous alloy strips in this embodiment differs from that in the first embodiment only in that it includes a heating roller and a pressing portion and a heating portion for pressing the metal strip; therefore, an enlarged schematic diagram of the used portion will be provided for explanation. Moreover, since the same structure as in the first embodiment has the same effect, the same reference numerals are used and the description is omitted.

[0063] Figure 3 This is an enlarged schematic diagram of the pressing section and the heating section in the heat treatment apparatus for amorphous alloy thin strips, as described in the second embodiment. Figure 3 As shown, the heat treatment section includes heating rollers 6a, 6b, 6c, and 6d, a thin strip pressing metal strip 7, a thin strip pressing metal strip 9, and a guide roller 10. An amorphous alloy thin strip 2 can be arranged between the thin strip pressing metal strip 7 and the thin strip pressing metal strip 9.

[0064] That is, multiple heating rollers 6a, 6b, 6c, and 6d are arranged with different heights when viewed from the direction of travel of the amorphous alloy strip 2, and partially overlap. Heating rollers 6a and 6b used to heat one side of the amorphous alloy strip 2 are alternately arranged with heating rollers 6c and 6d used to heat the other side. Heating rollers 6a and 6b used to heat one side surround a first strip member (strip pressing metal strip 7), while rollers 6c and 6d used to heat the other side surround a second strip member (strip pressing metal strip 9). In the portion of heating rollers 6a and 6b surrounding the first strip member (strip pressing metal strip 7), the first strip member becomes part of the heating section for one side of the amorphous alloy strip 2, and the second strip member (strip pressing metal strip 9) becomes the pressing section. Furthermore, in the portions of the heating rollers 6c and 6d surrounding the second belt member (thin strip pressing metal strip 9), the second belt member becomes part of the heating section for the other side of the amorphous alloy thin strip 2, and the first belt member (thin strip pressing metal strip 7) becomes the pressing section.

[0065] Thin-strip pressing metal strip 9, like thin-strip pressing metal strip 7, is an example of a flexible component, a strip component capable of moving via rollers. From the viewpoints of flexibility, strength, and heat resistance, metal components are preferred for flexible components (strip components).

[0066] The thin strip pressing metal strip 7 presses the amorphous alloy thin strip 2 against the thin strip pressing metal strip 9 along the convex surface (curved surface of the outer periphery) of the heating roller 6c. That is, the thin strip pressing metal strip 7 presses the amorphous alloy thin strip 2 against the thin strip pressing metal strip 9 along the convex surface (curved surface of the outer periphery) of the heating roller 6c from the opposite side of the contact surface. Similarly, the thin strip pressing metal strip 9 presses the amorphous alloy thin strip 2 against the thin strip pressing metal strip 7 along the convex surface (curved surface of the outer periphery) of the heating roller 6b from the opposite side of the contact surface.

[0067] That is, in this embodiment, heating roller 6a, heating roller 6b, and thin strip pressing metal strip 7, and heating roller 6c, heating roller 6d, and thin strip pressing metal strip 9 are respectively the pressing parts in the heat treatment apparatus 1, and at the same time constitute the heating parts in the heat treatment apparatus 1.

[0068] Here, only one of the heating rollers 6a, 6b, 6c, and 6d is driven, while the other rollers are driven via the thin strip pressing metal belt 7 and 9, thereby enabling synchronous operation without complex mechanisms. In this embodiment, the heating roller 6b is provided with a driving force, while the heating rollers 6a, 6c, and 6d are mechanically driven by the thin strip pressing metal belt 7 and 9. This avoids complex control measures such as electrical synchronization of the heating rollers 6a, 6b, 6c, and 6d, and eliminates the need to correct for asynchrony caused by differences in thermal expansion among the heating rollers 6a, 6b, 6c, and 6d.

[0069] Next, an enlarged schematic diagram of the heat treatment section in the heat treatment apparatus for amorphous alloy thin strips, as described in the second embodiment, is shown. Figure 3 The heat treatment method of this embodiment will be described.

[0070] After the amorphous alloy strip 2, supplied along the strip guide slope 4, is clamped into the strip pressing metal strip 7 and the strip pressing metal strip 9, the strip begins to be automatically wound.

[0071] The amorphous alloy strip 2 abuts against the strip pressing metal strip 9 along the convex surface (curved surface of the outer periphery) of the heating roller 6c and moves. The strip pressing metal strip 7 presses the abutting part of the amorphous alloy strip against the strip pressing metal strip 9 along the convex surface (curved surface of the outer periphery) of the heating roller 6c from the opposite side of the abutting surface and moves.

[0072] Next, the amorphous alloy strip 2 abuts against the strip pressing metal strip 7 along the convex surface (curved surface of the outer periphery) of the heating roller 6b and moves. The strip pressing metal strip 9 presses the abutting part of the amorphous alloy strip against the strip pressing metal strip 7 along the convex surface (curved surface of the outer periphery) of the heating roller 6b from the opposite side of the abutting surface and moves.

[0073] The speeds of the thin strip pressing metal strip 7 and the thin strip pressing metal strip 9 are different from the speed of the amorphous alloy thin strip 2, which can cause sliding. Preferably, the thin strip pressing metal strip 7, the thin strip pressing metal strip 9, and the amorphous alloy thin strip 2 move together.

[0074] The amorphous alloy strip 2, passing between the strip pressing metal strips 7 and 9, is discharged along the guide roller 10 in the direction of the hollow arrow in the figure. The discharged amorphous alloy strip 2 moves along the strip guide ramp 4 and is wound by a strip winding machine (not shown).

[0075] When using amorphous alloy strips, for example, in motor stator cores, straight strips are required. If, as in the first embodiment, the strip is pressed against a convex surface in only one direction, the curvature direction of the convex surface will be bent. Therefore, to correct this bending, the strip must be reversed and heat-treated again. However, if, as in this embodiment, the amorphous alloy strip is pressed against convex surfaces facing different directions sequentially, the bending in the curvature direction of the convex surface can be corrected without changing the strip's surface, thus efficiently obtaining heat-treated strips with minimal bending.

[0076] Example

[0077] The following describes the embodiments.

[0078] An amorphous alloy strip containing Fe-based amorphous alloy, with a width of 60 mm and a thickness of 24.8 μm, is prepared to be formed by the single-roll method.

[0079] (Example 1)

[0080] First, using the first embodiment, without applying tension to the amorphous alloy strip 2, the amorphous alloy strip 2 is moved at a speed of 200 mm / s, and both sides of the strip are heat-treated at 520°C, thereby manufacturing Example 1.

[0081] Subsequently, the magnetization curves (BH curves) of the heat-treated amorphous alloy strip 2 were measured. Measurements were performed using a single-plate tester connected to a BH analyzer (SY-8218 manufactured by Iwasaki Tsushinki). The insert sample spool width and yoke length of the single-plate tester used in the measurement were 25 mm. Therefore, for a square sample with one side of 25 mm, the BH curves in each direction were measured by changing the insertion direction of the sample by 90°, thus enabling the evaluation of the magnetic anisotropy of the sample. Therefore, a square sample with one side of 25 mm was cut from the heat-treated amorphous alloy strip 2, and the BH curves in the length and width directions of the strip were measured respectively. Furthermore, when cutting the square sample, it was cut from near the center of the amorphous alloy strip 2, with one side parallel to the length direction of the strip (and thus the other side parallel to the width direction). The BH curves in each direction are shown below. Figure 4 (a)

[0082] (Comparative Example 1)

[0083] On the other hand, the amorphous alloy strip was brought into contact with a heated convex surface and mechanically constrained, and then moved. Heat treatment was performed through rapid heating and cooling, demonstrating the results obtained by the existing method. Here, to ensure stable contact between the amorphous alloy strip 2 and the convex surface, tension needs to be applied to the amorphous alloy strip 2 to press it against the convex surface. Therefore, comparative example 1 was produced by applying a tension of 2 [kgf] to the amorphous alloy strip 2, bringing it into contact with a heated roller surface, and moving it to perform heat treatment. Similar to the example, the BH curves of the amorphous alloy strip in the length and width directions were measured. The results are shown below. Figure 4 (b)

[0084] After heat treatment using existing methods, according to Figure 4 As can be seen from (b), the BH curves differ in the length and width directions, resulting in magnetic anisotropy. On the other hand, according to the present invention, as... Figure 4 As shown in (a), the BH curves are not different in the length and width directions, indicating no magnetic anisotropy. Furthermore, Figure 4 The BH curves were all measured at a frequency of 1 kHz and a maximum magnetic flux density of 1.5 T. However, even when the frequency (including DC) or the maximum magnetic flux density was changed during the measurement of the BH curves, Figure 4 The result (i.e., the presence or absence of magnetic anisotropy) remains unchanged.

[0085] (Example 2)

[0086] Next, using the second embodiment, without applying tension to the amorphous alloy strip 2, the amorphous alloy strip 2 was moved at a speed of 17 mm / s, and both sides of the strip were heat-treated at 480°C to produce Example 2.

[0087] (Comparative Example 2)

[0088] Comparative Example 2: A heat-treated amorphous alloy strip 2 was manufactured using existing methods. Heat treatment was performed by applying a tension of 2 kgf to a convex curved surface heated to 490°C while contacting and moving the surface with it.

[0089] Figure 5 of (a) Figure 5 of (b) Figure 5 Figures (c) represent Example 1, Example 2, and Comparative Example 2, respectively. It can be seen that... Figure 5 In Example 1 of (a), due to the convex heat treatment, the thin strip bends, and therefore both ends of the thin strip curl up by about 6 mm, but Figure 5 In Example 2 (b), the bending of the thin strip was corrected without any lifting. On the other hand, it is known that... Figure 5 In Comparative Example 2 (c), since the strip was subjected to heat treatment while tension was applied, the strip did not warp, just like in Example 2.

[0090] Next, the BH curves of Example 2 and Comparative Example 2, which were respectively formed as straight thin strips, were measured. The results are shown below. Figure 6 .

[0091] Figure 6 (a) shows the BH curve when a magnetic field with a frequency of 1 kHz and a strength of 100 A / m is applied. Figure 6 (b) is the BH curve when a magnetic field with a frequency of 1 kHz and an intensity of 300 A / m is applied.

[0092] It can be known Figure 6 (a) and Figure 6 (b) shows that, compared with Comparative Example 2, the BH hysteresis loop rises well and the magnetic properties are excellent.

[0093] Based on the above, by using the embodiments of the present invention, heat conduction can be achieved without applying excessive tension to the amorphous alloy strip, and the amorphous alloy strip can be manufactured without magnetic anisotropy or strip breakage. Especially when the amorphous alloy strip is an Fe-based nanocrystalline alloy, excessive temperature rise is easily caused by the self-heating during crystallization of nanocrystals, thus requiring heat dissipation to the heating roller or convex surface. Conventionally, to achieve this, the strip is forcefully pressed against the heating roller or convex surface by applying strong tension, thereby reducing contact thermal resistance and improving the heat dissipation efficiency towards the heating roller or convex surface, thus suppressing excessive temperature rise.

[0094] According to an embodiment of the present invention, by using a pressure-bearing thin strip, it is possible to reduce the contact thermal resistance without applying excessive tension to the thin strip.

[0095] Moreover, in most cases, there are fluctuations in the width direction of the amorphous alloy strip caused by the difference in cooling rate during casting (hereinafter referred to as lateral waves). The contact between the same part and the heater deteriorates, so the annealing process is prone to become incomplete. If the embodiment of the present invention is used, since the heated strip is pressed against the whole strip, sufficient heat treatment can be performed even if there are lateral waves.

[0096] Furthermore, in embodiments of the present invention, by pressing the amorphous alloy strip against its surface and back using a belt or roller, deformation such as wrinkles or stripes that easily occur during the crystallization of the amorphous alloy strip can be suppressed. Here, examples illustrating the deformation state of the amorphous alloy strip before and after heat treatment in embodiments of the present invention will be shown. Figure 7 Specifically, the changes in the plastic processing groove formed by pressing a 9.3 mm diameter annular marking punch against the surface of an amorphous alloy strip under a specified load are shown before and after heat treatment. Figure 7 (a) indicates before heat treatment. Figure 7 (b) indicates that after heat treatment, it can be known that Figure 7 In (a), deformation of the reflection or background caused by the deformation during processing can be observed, but... Figure 7 In (b), the reflection or deformation is eliminated after passing through the heat treatment mechanism of the embodiment of the present invention.

[0097] The embodiments of the invention have now been described, but the invention is not limited to these embodiments. Modifications may be made within the scope of the claims.

Claims

1. A heat treatment method for amorphous alloy thin strips, characterized in that... The process includes the following steps: The amorphous alloy strip is brought into thermal contact with the convex surface of the heating roller for heating, and The portion of the amorphous alloy strip that abuts against the convex surface is pressed against the belt member conveyed via two heated rollers from the opposite side of the abutting surface, causing the amorphous alloy strip to move.

2. The heat treatment method for amorphous alloy thin strips according to claim 1, characterized in that: The belt component is a metal component.

3. The heat treatment method for amorphous alloy thin strips according to claim 2, characterized in that: The belt component is heated while being pressed against it.

4. The heat treatment method for amorphous alloy thin strips according to claim 3, characterized in that: The process is performed multiple times by changing the surface of the amorphous alloy strip that the convex surface abuts against.

5. The heat treatment method for amorphous alloy thin strips according to any one of claims 1 to 4, characterized in that: The amorphous alloy strip is a nanocrystalline soft magnetic material.

6. A heat treatment apparatus for amorphous alloy strips, wherein heat treatment is performed while the amorphous alloy strip is being moved, characterized in that... Includes a combination of the following components: The heating section comprises a heating roller and includes a convex surface of the heating roller for contacting and heating the amorphous alloy strip; and The pressing part presses the amorphous alloy strip against the convex surface from the opposite side of the abutting surface, and the pressing part is a strip member that can move via two heated rollers.

7. The heat treatment apparatus for amorphous alloy thin strips according to claim 6, characterized in that: The belt component is a metal component.

8. The heat treatment apparatus for amorphous alloy thin strips according to claim 7, characterized in that: The two heating drums include a heating mechanism for heating the belt components.

9. The heat treatment apparatus for amorphous alloy strips according to any one of claims 6 to 8, wherein, The amorphous alloy strip includes multiple such combinations in its travel direction, and in adjacent combinations, the heating portion and the strip member have opposite positional relationships relative to the amorphous alloy strip.

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