Amorphous nanocrystalline magnetically soft alloy continuous heat treatment device and process based on radio frequency induction heating

Abstract

The invention discloses an amorphous nanocrystalline magnetically soft alloy continuous heat treatment device and process based on radio frequency induction heating, belongs to the technical field of heat treatment, and solves the technical problem that existing rapid heat treatment equipment cannot meet the requirements of an amorphous nanocrystalline magnetically soft alloy heat treatment process. According to the technical scheme, the device comprises an automatic belt feeding machine, an upper pressing plate, a lower pressing plate, a coil and a coiling device, a sliding groove is formed in the middle of the upper surface of the lower pressing plate, and an amorphous nanocrystalline magnetically soft alloy strip is fed in along the sliding groove; a plurality of coils are arranged in the middles of the upper surfaces of the upper pressing plate and the lower pressing plate at equal intervals, the odd-numbered coils are sequentially connected in series through a first hollow conductive tube, the two ends of the first hollow conductive tube are electrically connected with the positive electrode and the negative electrode of a direct-current power source respectively, and the even-numbered coils are sequentially connected in series through a second hollow conductive tube. Two ends of the second hollow conductive tube are electrically connected with positive and negative electrodes of the radio frequency power supply respectively; on the basis, the invention discloses a continuous heat treatment process for the amorphous nanocrystalline magnetically soft alloy. The device is simple, uniform in heating and high in electric energy use efficiency.

Description

Technical Field

[0001] The present invention belongs to the field of heat treatment technology, and in particular relates to a continuous heat treatment device and process for an amorphous nanocrystalline soft magnetic alloy based on radio frequency induction heating. Background Art

[0002] The research and development and application of third-generation semiconductors have accelerated the development of power electronic equipment towards high frequency, miniaturization and high efficiency. Emerging fields such as 5G communications, new generation consumer electronics, and new energy vehicles have put forward higher process-soft magnetic performance requirements for Nanomet-based nanocrystalline soft magnetic materials.

[0003] Nanomet series nanocrystalline soft magnetic alloys have high B s ,Low H c The excellent soft magnetic properties such as high μ and high Fe content have always attracted much attention. However, the high Fe content in the alloy leads to weak amorphous forming ability and narrow crystallization sensitive zone, which makes the heat treatment heating rate more demanding. In order to further improve the nanocrystal precipitation process, effectively refine the nanocrystal size, reduce the local anisotropy and thus reduce the material H c Various rapid heat treatment technologies have been adopted, such as copper block preheating, laser surface heating, and flash thermal radiation heating, which have significantly improved the performance of nanocrystalline soft magnetic alloys. However, these methods have limitations such as uneven heating, narrow heat treatment area, high energy consumption, and complex equipment. The reason is that the above-mentioned rapid heating technologies mainly follow Fourier's law of heat conduction during heat transfer. However, in actual situations, the uneven internal structure of the material leads to delayed and rapid temperature changes inside and outside the sample during the transmission of thermal wave characteristics, making it impossible to ensure the synchronous uniformity of the temperature field inside the material. On this basis, the process of convective heat transfer will also cause temperature gradient differences, resulting in uneven temperature distribution on the surface and inside of the material; the surface laser heating method can achieve a narrow effective area of ​​heat treatment, which is greatly affected by the laser spot diameter, scanning speed, and power. At the same time, it is necessary to select a laser of the appropriate band, which is expensive, the equipment is complex, and the efficiency is low, which cannot meet the needs of industrial production; for the double-sided preheating method of copper blocks, the copper blocks need to be continuously heated in advance, which consumes a lot of energy. At the same time, high-purity and high-conductivity copper blocks are required to reduce the loss of heat transfer, and the cost is high. The actual temperature of the strip cannot be directly measured during the heat treatment process, and there is a temperature lag effect; the flash thermal radiation method requires a continuous flow of a large current to generate heat, which consumes extremely high energy. At the same time, the halogen tungsten lamp will shorten its life and increase the cost if it works at a high current density for a long time, making it impossible to achieve industrial continuous production. Summary of the Invention

[0004] The main purpose of the present invention is to overcome the shortcomings of the existing technology and solve the technical problems of uneven heating, narrow heat treatment area, high energy consumption and complex equipment after the existing rapid heat treatment of Nanomet series nanocrystalline soft magnetic alloy strips. The present invention provides an amorphous nanocrystalline soft magnetic alloy continuous heat treatment device and process based on radio frequency induction heating.

[0005] The present invention is achieved through the following technical solution: a continuous heat treatment device for amorphous, nanocrystalline, and soft magnetic alloys based on radio frequency induction heating, which includes an automatic tape feeder, an upper pressing plate, a lower pressing plate, a coil, and a winding device. The automatic tape feeder unwinds the amorphous, nanocrystalline, and soft magnetic alloy strips and then winds them into a coil through the winding device, wherein: The upper pressing plate and the lower pressing plate are both made of transparent glass. The upper pressing plate and the lower pressing plate are arranged opposite to each other, and the upper pressing plate is arranged directly above the lower pressing plate. The arrangement of the upper pressing plate and the lower pressing plate can prevent the amorphous nanocrystalline soft magnetic alloy strips from deflecting and vibrating under the action of the high-frequency magnetic field, avoid uneven heating, and facilitate infrared temperature measurement; a chute is arranged in the middle of the upper surface of the lower pressing plate along the length direction, and the amorphous nanocrystalline soft magnetic alloy strips are fed along the chute; the core parts of the front and rear sides of the lower surface of the lower pressing plate are respectively fixedly connected to the hydraulic drive rods arranged vertically upward, and the hydraulic drive rods move synchronously to drive the lower pressing plate to move in the vertical direction; Guide sleeves are respectively provided at the four corners of the lower pressing plate, and limiting grooves are respectively provided at positions corresponding to the guide sleeves on the upper pressing plate. Springs are provided in the limiting grooves, and hydraulic guide rods penetrate the guide sleeves from bottom to top and extend into the corresponding limiting grooves. The upper end of the hydraulic guide rod is fixed with a mounting tray, and the hydraulic guide rod extends or retracts along the guide sleeve, thereby driving the upper pressing plate to contact or separate from the upper surface of the amorphous nanocrystalline soft magnetic alloy strip. A number of coils are arranged at equal intervals in the middle of the upper surface of the upper pressing plate and the middle of the lower surface of the lower pressing plate, and the outer shape of the coil is set to be semicircular or semi-flat rectangular. Among the coils on the same side of the upper pressing plate, the odd-numbered coils are connected in series in sequence through the first hollow conductive tube, and the two ends of the first hollow conductive tube are electrically connected to the positive and negative poles of the DC power supply respectively. The even-numbered coils are connected in series in sequence through the second hollow conductive tube, and the two ends of the second hollow conductive tube are electrically connected to the positive and negative poles of the radio frequency power supply respectively. The coils on the same side of the upper pressing plate have the same structure as the coils on the same side of the lower pressing plate; the ends of the coils pass through the corresponding upper pressing plate or lower pressing plate respectively, and the coils arranged on the upper pressing plate and the coils arranged on the lower pressing plate are symmetrical to each other. When the opposite surfaces of the upper pressing plate and the lower pressing plate are in contact, the corresponding coils on the upper pressing plate and the lower pressing plate contact and form a closed loop.

[0006] Furthermore, the thickness of the upper pressing plate and the lower pressing plate are both 0.2 mm.

[0007] Furthermore, the depth of the chute is equal to the thickness of the amorphous nanocrystalline soft magnetic alloy strip, and the width of the chute is equal to the width of the amorphous nanocrystalline soft magnetic alloy strip.

[0008] Furthermore, the thickness of the amorphous nanocrystalline soft magnetic alloy strip is 20 μm-25 μm, the width is 2 mm-3 mm, and the density is 7.5 g / cm 3 .

[0009] Furthermore, the DC power supply has a current of 20A and is used to provide a magnetic field with a magnetic field strength of 500Gs; the RF power supply is an AC power supply with a current of 500A and a frequency of 1MHz.

[0010] A heat treatment process using the above-mentioned continuous heat treatment device comprises the following steps: S1. First, the front and rear hydraulic drive rods move upward synchronously, driving the lower platen to move vertically upward. At the same time, the hydraulic guide rod extends along the guide sleeve, and the tray squeezes the spring to lift the upper platen to a predetermined height. The hydraulic drive rod and the hydraulic guide rod stop moving. S2. The amorphous, nanocrystalline, soft magnetic alloy coil to be heat treated is mounted on an automatic tape feeder, which unwinds the amorphous, nanocrystalline, soft magnetic alloy coil to be heat treated and fits the amorphous, nanocrystalline, soft magnetic alloy strip to be heat treated into the slideway. S3. The hydraulic drive rod remains stationary, the hydraulic guide rod retracts along the guide sleeve, and the upper platen descends accordingly until the opposing surfaces of the upper and lower plates are in contact, and the amorphous nanocrystalline soft magnetic alloy strip is located in the closed chute; a direct current of 20 A is then passed into the first hollow conductive tube, and at the same time, an alternating current of 500 A and a frequency of 1 MHz is passed into the second hollow conductive tube; S4. The automatic tape feeder and the winding device work continuously. The amorphous nanocrystalline soft magnetic alloy strip moves slowly along the slide under the condition of radio frequency induction heating. The feeding speed of the amorphous nanocrystalline soft magnetic alloy strip is 1mm / s-3mm / s. The radio frequency induction heating temperature is 520℃~570℃, and the holding time is 3s-5s. The heat-treated amorphous nanocrystalline soft magnetic alloy strip passes through the slide and is wound on the winding device to obtain an amorphous nanocrystalline soft magnetic alloy core.

[0011] Furthermore, in step S4, an infrared thermometer is provided above the upper pressing plate, and the infrared thermometer irradiates infrared spots on the surface of the strip through the upper pressing plate to monitor the heat treatment temperature of the surface of the amorphous nanocrystalline soft magnetic alloy strip in real time.

[0012] The beneficial effects of the present invention are: 1. RF induction ultra-fast heating technology utilizes electromagnetic energy in the 50Hz-500kHz frequency range to achieve non-contact heating of workpieces. It offers significant advantages, including simple equipment, uniform heating, high energy efficiency, extremely low heat transfer losses, controllable magnetic field size, zero pollution, and reduced processing time. It also mitigates the embrittlement of strip materials after conventional heat treatment. The core components of induction heating equipment, primarily consisting of an RF power supply and induction coil, offer a simple structure, enabling industrial continuous winding and annealing automated integrated production.

[0013] 2. Amorphous ribbon, as a metal workpiece, rapidly generates an induced potential in a high-frequency induction coil, which in turn generates a large induced current, enabling rapid heating of the material. Heating rates can reach 102°C / s. The propagation rate of electromagnetic energy is equal to the speed of light, resulting in strong penetrating power. During the heat treatment process, the core and surface of the material are heated almost simultaneously, eliminating temperature gradients and minimizing heat loss. Furthermore, the power efficiency is as high as 75%-80%, meeting the requirements of green development. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is a schematic diagram of the top view of the structure of the present invention; Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure of the middle AA plane; Figure 3 This is the crystal phase diagram of amorphous nanocrystalline soft magnetic alloy strips after heat treatment. DETAILED DESCRIPTION

[0015] The present invention will be described in further detail below with reference to the accompanying drawings and examples.

[0016] The continuous heat treatment device for amorphous, nanocrystalline, and soft magnetic alloys based on radio frequency induction heating comprises an automatic tape feeder 1, an upper pressing plate 2, a lower pressing plate 3, a coil 4, and a winding device 5. The automatic tape feeder 1 unwinds an amorphous, nanocrystalline, and soft magnetic alloy strip 6 and then winds it into a coil through the winding device 5, wherein: The upper pressing plate 2 and the lower pressing plate 3 are both made of transparent glass. The upper pressing plate 2 and the lower pressing plate 3 are arranged opposite to each other, and the upper pressing plate 2 is arranged directly above the lower pressing plate 3; a chute 7 is provided in the middle of the upper surface of the lower pressing plate 2 along the length direction, and the amorphous nanocrystalline soft magnetic alloy strip 6 is fed along the chute 7; the core parts of the front and rear sides of the lower surface of the lower pressing plate 3 are respectively fixedly connected to the hydraulic drive rod 8 arranged vertically upward, and the hydraulic drive rod 8 moves synchronously to drive the lower pressing plate 3 to move in the vertical direction; Guide sleeves 9 are respectively provided at the four corners of the lower pressing plate 3, and limiting grooves 10 are respectively provided at the positions of the upper pressing plate 3 corresponding to the guide sleeves 9. A spring 11 is provided in the limiting groove 10, and a hydraulic guide rod 13 penetrates the guide sleeve 9 from bottom to top and extends into the corresponding limiting groove 10. The upper end of the hydraulic guide rod 13 is fixedly mounted with a tray 12. The hydraulic guide rod 13 extends or retracts along the guide sleeve 9, thereby driving the upper pressing plate 2 to contact or separate from the upper surface of the amorphous nanocrystalline soft magnetic alloy strip 6; A plurality of coils 4 are arranged at equal intervals in the middle of the upper surface of the upper pressing plate 2 and the middle of the lower surface of the lower pressing plate 3. The outer shape of the coil 4 is set to be semicircular or semi-flat rectangular. Among the coils 4 on the same side of the upper pressing plate 2, the odd-numbered coils 4 are connected in series in sequence through the first hollow conductive tube 14, and the two ends of the first hollow conductive tube 14 are respectively electrically connected to the positive and negative poles of the DC power supply. The even-numbered coils 4 are connected in series in sequence through the second hollow conductive tube 15, and the two ends of the second hollow conductive tube 15 are respectively electrically connected to the positive and negative poles of the radio frequency power supply. The coil 4 on the same side of the plate 2 has the same structure as the coil 4 on the same side of the lower pressing plate 3; the ends of the coil 4 pass through the corresponding upper pressing plate 2 or the lower pressing plate 3 respectively, and the coil 4 set on the upper pressing plate 2 and the coil 4 set on the lower pressing plate 3 are symmetrical to each other. When the opposite surfaces of the upper pressing plate 2 and the lower pressing plate 3 are in contact, the corresponding coils 4 on the upper pressing plate 2 and the lower pressing plate 3 are in contact and form a closed loop. Since the size of the amorphous nanocrystalline soft magnetic alloy strip 6 in the thickness direction is very small, the influence of the direction and size of the magnetic field at the interface position of the coil 4 can be almost ignored.

[0017] Furthermore, the thickness of the upper pressing plate 2 and the lower pressing plate 3 are both 0.2 mm.

[0018] Furthermore, the depth of the chute 7 is equal to the thickness of the amorphous nanocrystalline soft magnetic alloy strip 6 , and the width of the chute 7 is equal to the width of the amorphous nanocrystalline soft magnetic alloy strip 6 .

[0019] Furthermore, the thickness of the amorphous nanocrystalline soft magnetic alloy strip 6 is 20 μm-25 μm, the width is 2 mm-3 mm, and the density is 7.5 g / cm 3 .

[0020] Furthermore, the DC power supply has a current of 20A and is used to provide a magnetic field with a magnetic field strength of 500Gs; the RF power supply is an AC power supply with a current of 500A and a frequency of 1MHz.

[0021] A heat treatment process using the above-mentioned continuous heat treatment device comprises the following steps: S1. First, the front and rear hydraulic drive rods 8 move upward synchronously, thereby driving the lower platen 3 to move upward in the vertical direction. At the same time, the hydraulic guide rod 13 extends along the guide sleeve 9, and the tray 12 squeezes the spring 11 to lift the upper platen 2 to a predetermined height. The hydraulic drive rods 8 and the hydraulic guide rods 13 stop moving. S2. The amorphous, nanocrystalline, soft magnetic alloy coil to be heat treated is mounted on the automatic tape feeder 1. The automatic tape feeder 1 unwinds the amorphous, nanocrystalline, soft magnetic alloy coil to be heat treated and fits the amorphous, nanocrystalline, soft magnetic alloy strip 6 to be heat treated into the chute 7. S3, the hydraulic drive rod 8 remains in position, the hydraulic guide rod 13 retracts along the guide sleeve 9, and the upper pressing plate 2 is lowered until the opposing surfaces of the upper pressing plate 2 and the lower pressing plate 3 are in contact, and the amorphous nanocrystalline soft magnetic alloy strip 6 is located in the closed chute 7; then a direct current of 20A is passed into the first hollow conductive tube 14, and at the same time, an alternating current of 500A and a frequency of 1MHz is passed into the second hollow conductive tube 15; S4, the automatic tape feeder 1 and the winding device 5 work continuously, and the amorphous nanocrystalline soft magnetic alloy strip 6 moves slowly along the slide 7 under the condition of radio frequency induction heating. The feeding speed of the amorphous nanocrystalline soft magnetic alloy strip 6 is 1mm / s-3mm / s, the radio frequency induction heating temperature is 520℃~570℃, and the holding time is 3s-5s. The amorphous nanocrystalline soft magnetic alloy strip 6 after heat treatment passes through the slide 7 and is wound on the winding device 5 to obtain an amorphous nanocrystalline soft magnetic alloy core.

[0022] Furthermore, in step S4, an infrared thermometer is provided above the upper pressing plate 2, and the infrared thermometer irradiates infrared spots on the surface of the strip through the upper pressing plate 2 to monitor the heat treatment temperature of the surface of the amorphous nanocrystalline soft magnetic alloy strip 6 in real time.

[0023] Compared with the traditional tube furnace heat treatment method, after the amorphous nanocrystalline soft magnetic alloy strip 6 is heat-treated by the present invention, the size of the nanocrystalline grains is reduced from 21.68nm to 17.97nm, and the density of the nanocrystalline is reduced from 4.7 × 10 22 m -3 Increased to 7.7 × 10 22 m -3 , effectively reducing the grain size of the alloy, increasing the precipitation density of nanocrystals, and enhancing the magnetic exchange coupling. The soft magnetic properties of the alloy are: B s = 1.58 T, H c = 2.48 A / m, μ e at 1 kHz = 16400, the comprehensive soft magnetic properties of the alloy are significantly improved.

[0024] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in the present invention should be included in the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be based on the scope of protection of the claims.

Claims

1. A continuous heat treatment device for amorphous nanocrystalline soft magnetic alloy based on radio frequency induction heating, comprising an automatic tape feeder (1), an upper pressing plate (2), a lower pressing plate (3), a coil (4) and a winding device (5), wherein the automatic tape feeder (1) unwinds the amorphous nanocrystalline soft magnetic alloy strip (6) and then winds it into a coil through the winding device (5), and the device is characterized in that: The upper pressing plate (2) and the lower pressing plate (3) are both made of transparent glass. The upper pressing plate (2) and the lower pressing plate (3) are arranged opposite to each other, and the upper pressing plate (2) is arranged directly above the lower pressing plate (3). A slide groove (7) is arranged in the middle of the upper surface of the lower pressing plate (2) along the length direction, and the amorphous nanocrystalline soft magnetic alloy strip (6) is fed along the slide groove (7). The core parts of the front and rear sides of the lower surface of the lower pressing plate (3) are respectively fixedly connected to hydraulic drive rods (8) arranged vertically upward, and the hydraulic drive rods (8) move synchronously to drive the lower pressing plate (3) to move in the vertical direction. Guide sleeves (9) are respectively arranged at the four corners of the lower pressing plate (3), and limiting grooves (10) are respectively arranged at positions of the upper pressing plate (3) corresponding to the guide sleeves (9), and springs (11) are arranged in the limiting grooves (10). A hydraulic guide rod (13) penetrates the guide sleeves (9) from bottom to top and extends into the corresponding limiting grooves (10). The upper end of the hydraulic guide rod (13) is fixedly mounted with a tray (12). The hydraulic guide rod (13) extends or retracts along the guide sleeves (9), thereby driving the upper pressing plate (2) to contact or separate from the upper surface of the amorphous nanocrystalline soft magnetic alloy strip (6); A plurality of coils (4) are arranged at equal intervals in the middle of the upper surface of the upper pressing plate (2) and in the middle of the lower surface of the lower pressing plate (3). The outer shape of the coils (4) is arranged in a semicircular or semi-flat rectangular shape. Among the coils (4) on the same side of the upper pressing plate (2), the odd-numbered coils (4) are sequentially connected in series through a first hollow conductive tube (14), and the two ends of the first hollow conductive tube (14) are respectively electrically connected to the positive and negative electrodes of a DC power supply. The even-numbered coils (4) are sequentially connected in series through a second hollow conductive tube (15), and the second hollow conductive tube (16) is electrically connected to the positive and negative electrodes of a DC power supply. The two ends of the upper pressing plate (2) and the lower pressing plate (3) are electrically connected to the positive and negative electrodes of the radio frequency power supply respectively. The coil (4) on the same side of the upper pressing plate (2) and the coil (4) on the same side of the lower pressing plate (3) have the same structure. The ends of the coil (4) respectively penetrate the corresponding upper pressing plate (2) or lower pressing plate (3), and the coil (4) arranged on the upper pressing plate (2) and the coil (4) arranged on the lower pressing plate (3) are symmetrical to each other. When the opposite surfaces of the upper pressing plate (2) and the lower pressing plate (3) are in contact, the corresponding coils (4) on the upper pressing plate (2) and the lower pressing plate (3) are in contact and form a closed loop.

2. The continuous heat treatment device for amorphous nanocrystalline soft magnetic alloy based on radio frequency induction heating according to claim 1 is characterized in that: The thickness of the upper pressing plate (2) and the lower pressing plate (3) are both 0.2 mm.

3. The continuous heat treatment device for amorphous nanocrystalline soft magnetic alloy based on radio frequency induction heating according to claim 1 is characterized in that: The depth of the slide groove (7) is equal to the thickness of the amorphous nanocrystalline soft magnetic alloy strip (6), and the width of the slide groove (7) is equal to the width of the amorphous nanocrystalline soft magnetic alloy strip (6).

4. The continuous heat treatment device for amorphous nanocrystalline soft magnetic alloy based on radio frequency induction heating according to claim 1 or 3, characterized in that: The amorphous nanocrystalline soft magnetic alloy strip (6) has a thickness of 20 μm-25 μm, a width of 2 mm-3 mm, and a density of 7.5 g / cm 3 .

5. The continuous heat treatment device for amorphous nanocrystalline soft magnetic alloy based on radio frequency induction heating according to claim 1 is characterized in that: The DC power supply has a current of 20A and is used to provide a magnetic field with a magnetic field strength of 500Gs; the RF power supply is an AC power supply with a current of 500A and a frequency of 1MHz.

6. A heat treatment process using the continuous heat treatment device as claimed in claim 1, characterized in that: The following steps are involved: S1. First, the front and rear hydraulic drive rods (8) move upward synchronously, thereby driving the lower pressure plate (3) to move upward in the vertical direction. At the same time, the hydraulic guide rod (13) extends along the guide sleeve (9), and the tray (12) squeezes the spring (11) to lift the upper pressure plate (2) to a predetermined height. The hydraulic drive rod (8) and the hydraulic guide rod (13) stop moving. S2, installing the amorphous nanocrystalline soft magnetic alloy coil to be heat treated on the automatic tape feeder (1), the automatic tape feeder (1) unfolds the amorphous nanocrystalline soft magnetic alloy coil to be heat treated, and makes the amorphous nanocrystalline soft magnetic alloy strip (6) to be heat treated just fit in the slide groove (7); S3, the hydraulic drive rod (8) remains in position, the hydraulic guide rod (13) retracts along the guide sleeve (9), and the upper pressing plate (2) is lowered until the surfaces of the upper pressing plate (2) and the lower pressing plate (3) are in contact with each other, and the amorphous nanocrystalline soft magnetic alloy strip (6) is located in the closed slide groove (7); then a direct current of 20A is passed into the first hollow conductive tube (14), and at the same time, an alternating current of 500A is passed into the second hollow conductive tube (15), and the frequency of the alternating current is 1MHz; S4, the automatic tape feeder (1) and the winding device (5) work continuously, the amorphous nanocrystalline soft magnetic alloy strip (6) moves slowly along the slide groove (7) under the condition of radio frequency induction heating, the feeding speed of the amorphous nanocrystalline soft magnetic alloy strip (6) is 1mm / s-3mm / s, the radio frequency induction heating temperature is 520℃~570℃, the insulation time is 3s-5s, and the amorphous nanocrystalline soft magnetic alloy strip (6) after heat treatment passes through the slide groove (7) and is wound on the winding device (5) to obtain the amorphous nanocrystalline soft magnetic alloy core.

7. The heat treatment process of the continuous heat treatment device according to claim 6, characterized in that: In step S4, an infrared thermometer is arranged above the upper pressing plate (2), and the infrared thermometer irradiates an infrared spot on the surface of the strip through the upper pressing plate (2), so as to monitor the heat treatment temperature of the surface of the amorphous nanocrystalline soft magnetic alloy strip (6) in real time.

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