Amorphous integrally-formed inductor based on ultra-low-voltage forming and preparation method of amorphous integrally-formed inductor

Abstract

The invention provides an amorphous integrally-formed inductor based on ultra-low-voltage forming and a preparation method of the amorphous integrally-formed inductor, and relates to the field of inductor ultra-low-voltage forming, and the method comprises the steps that prepared amorphous powder is obtained and pressed to obtain a compact amorphous T-shaped magnetic core; winding the amorphous T-shaped magnetic core, welding a material sheet to lead out a terminal on the wound magnetic core to obtain a coil-amorphous magnetic core, and placing the welded coil-amorphous magnetic core in a forming die for powder filling and low-pressure pressing to obtain an inductor body; performing spraying rust prevention treatment on the inductor body to obtain a prefabricated inductor; and removing the pins of the prefabricated inductor to obtain the amorphous integrally-formed inductor. The amorphous powder with low loss and high magnetic conductivity is adopted to form the integrated inductor in an ultra-low voltage mode, the deformation of the copper wire and the risk of high-voltage turn-to-turn short circuit of the copper wire are reduced, the risk of open circuit caused by high voltage at the welding point of the copper wire is also avoided, and the reliability of the integrated inductor is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of ultra-low pressure molding of inductors, and in particular to an amorphous one-piece molded inductor based on ultra-low pressure molding and a preparation method thereof. Background Art

[0002] As AI server frequencies increase, the demand for stable power supply and filtering becomes increasingly stringent, and integrated inductors address this issue. Chip inductor materials are transitioning from ferrite to metal soft magnetic materials, which offer the advantages of low voltage, high current resistance, and compact size. To meet the increasing demand for high computing power and the surge in demand for chips in high-power scenarios, integrated inductors made from amorphous powder cores are becoming mainstream, thanks to their high energy efficiency, small size, and ability to respond to large current changes.

[0003] In existing technologies, one-piece molded inductors generally use high-pressure molding technology (400Mpa-1000Mpa molding pressure) and a strip-type structure. Under this high-pressure molding process, the coil insulation layer is easily damaged, leading to the risk of short circuits. Furthermore, open circuit failures are prone to occur at the soldering corners of the strip, which is extremely disadvantageous for equipment such as the automotive industry, medical industry, and AI servers that require high reliability. Summary of the Invention

[0004] Based on this, the purpose of the present invention is to provide an amorphous one-piece molded inductor based on ultra-low pressure molding and a preparation method thereof, which is used to solve the technical problem in the existing technology that high-pressure molded inductors easily damage the coil insulation layer and cause short circuits.

[0005] In one aspect, the present invention provides a method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding, comprising: Obtaining the prepared amorphous powder and pressing it to obtain a dense amorphous T-shaped magnetic core; The amorphous T-shaped core is wound and welded to form a terminal on the wound core to obtain a coil-amorphous core. The welded coil-amorphous core is placed in a forming mold and filled with powder and pressed at low pressure to obtain the inductor body. Performing a spray-coating anti-rust treatment on the inductor body to obtain a prefabricated inductor; The prefabricated inductor is removed from its legs to obtain an amorphous integrally formed inductor.

[0006] In addition, the above-mentioned method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding according to the present invention may also have the following additional technical features: Furthermore, in the step of obtaining the prepared amorphous powder, the preparation method of the amorphous powder includes: Obtaining an amorphous powder, and passivating, coating, and granulating the amorphous powder to obtain a prepared amorphous powder; Among them, the coating method adopts magnetic powder glue coating, and the component addition amount of magnetic powder glue includes 2%-5% of magnetic powder and 40%-60% of silicone resin. The viscosity of the magnetic powder glue is 100pa*s-500pa*s.

[0007] Furthermore, the magnetic powder adhesive coating is granulated using an explosion-proof spray granulation equipment, and the granulated powder is an amorphous powder with a particle size of 200 mesh to 400 mesh and a fluidity of 35s±5s.

[0008] Furthermore, in the step of placing the welded coil-amorphous core in a forming mold for powder filling and low-pressure pressing to obtain the inductor body, the low-pressure pressing pressure is 60Mpa-80Mpa, the pressing temperature is 160°C, and the pressure is maintained for 60s-180s.

[0009] Furthermore, the magnetic permeability of the amorphous powder is 40H / m-60H / m, and the DC bias capability is 100 Oe.

[0010] Another aspect of the present invention provides an amorphous one-piece molded inductor based on ultra-low pressure molding, which is manufactured using the above-mentioned method for manufacturing an amorphous one-piece molded inductor based on ultra-low pressure molding.

[0011] The above-mentioned amorphous one-piece molded inductor based on ultra-low pressure molding and its preparation method, by using amorphous powder with lower loss and higher magnetic permeability to ultra-low pressure mold the one-piece inductor, on the one hand, the use of low-loss, high-magnetic permeability amorphous powder compared with conventional alloy powder molded one-piece inductor greatly reduces the loss of the molded inductor and improves the efficiency of the inductor; on the other hand, ultra-low pressure molding reduces the deformation of the copper wire compared with conventional molding, reduces the risk of short circuit between turns of the copper wire due to high voltage, and avoids the risk of open circuit caused by high voltage at the copper wire solder joint, thereby improving the reliability of the one-piece inductor; solves the technical problem in the existing technology that high-voltage molded inductors easily damage the coil insulation layer and cause short circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 This is a flow chart of a method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding in an embodiment of the present invention; Figure 2 Schematic diagram of the structure of an amorphous one-piece molded inductor based on ultra-low pressure molding in an embodiment of the present invention; Figure 3 This is the process flow of an amorphous one-piece molded inductor based on ultra-low pressure molding in an embodiment of the present invention; Figure 4 Schematic diagram of loss test results of integrated inductors prepared using ultra-low voltage technology using different powder materials according to an embodiment of the present invention; The following specific embodiments will further illustrate the present invention in conjunction with the above-mentioned drawings. DETAILED DESCRIPTION

[0013] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. The drawings illustrate several embodiments of the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present invention.

[0014] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0015] In order to solve the technical problem in the prior art that high-pressure molded inductors are prone to damaging the coil insulation layer and causing short circuits, the present application provides an amorphous one-piece molded inductor based on ultra-low pressure molding and a preparation method thereof. It innovatively adopts ultra-low pressure molding technology (≤80Mpa molding pressure), which solves the risk of open short circuits in molded inductors from the source, and the magnetic powder used adopts low-loss, high-permeability amorphous powder, so that the product not only has the characteristics of high reliability and excellent electromagnetic performance, but also can reduce the overall volume of the inductor. Furthermore, the present application adopts a T-shaped magnetic core molding process, prefabricating the magnetic core and then winding the wire on the magnetic core. On the one hand, it can increase the density of the magnetic core to increase the effective magnetic permeability of the magnetic core, and on the other hand, it can solve the internal cracks of conventional one-piece molded inductors.

[0016] For details, see Figure 1-Figure 3 The method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding provided in this application includes steps S101-S104: S101 , obtaining prepared amorphous powder and pressing it to obtain a dense amorphous T-shaped magnetic core.

[0017] In some optional embodiments, the preparation method of amorphous powder includes: obtaining amorphous powder material, passivating, coating, and granulating the amorphous powder material to obtain the prepared amorphous powder; wherein the amorphous powder material has a magnetic permeability of 40H / m-60H / m and a DC bias capability of 100 Oe; and the coating method is magnetic powder adhesive coating, the magnetic powder adhesive component addition amount includes 2%-5% magnetic powder and 40%-60% silicone resin, and the magnetic powder adhesive viscosity is 100Pa*s-500Pa*s. Furthermore, the magnetic powder adhesive coating is granulated using explosion-proof spray granulation equipment, and the granulated powder is an amorphous powder with a particle size of 200-400 mesh and a flowability of 35s±5s.

[0018] In some optional embodiments, after the dense amorphous T-shaped magnetic core is obtained by pressing, the obtained dense amorphous T-shaped magnetic core is annealed at a temperature of 430° C. and for a time of 2 hours.

[0019] Furthermore, the present application uses amorphous powder with high magnetic permeability and high saturation as raw material powder to replace conventional alloy powder (conventional alloy powder generally includes carbonyl iron powder and iron silicon chromium powder, among which the magnetic permeability of carbonyl iron powder is 30H / m-40H / m, and the bias capacity is 120 Oe; the magnetic permeability of iron silicon chromium powder is 30H / m-37H / m, and the bias capacity is 120 Oe). Since the amorphous powder itself has low loss (loss is less than 600kw / m3@50mT&100Hz), it is used in integrated inductors, which can greatly reduce the loss of the integrated inductors and improve the efficiency of the inductors.

[0020] S102, winding the amorphous T-shaped core, and welding the sheet to lead out terminals on the wound core to obtain a coil-amorphous core, placing the welded coil-amorphous core in a forming mold, filling powder and low-pressure pressing to obtain an inductor body.

[0021] In some optional embodiments, the low-pressure pressing pressure is 60 MPa-80 MPa, the pressing temperature is 160°C, and the pressure is maintained for 60-180 seconds. This application places the wound magnetic core in a mold and uses a low-pressure molding method, filling it with powder and pressing it. Compared to conventional methods, this can avoid excessive compression of the coil, reduce the risk of damage to the copper wire paint film, and greatly improve the reliability of the integrated inductor.

[0022] S103, performing anti-rust treatment by spraying on the inductor body to obtain a prefabricated inductor.

[0023] In some optional embodiments, the anti-rust paint used in the spraying process is acrylic paint for anti-rust treatment. Specifically, the color of the spray paint is gray, and the thickness of the spray paint is 0.15mm-0.35mm.

[0024] S104 , removing the pins of the prefabricated inductor to obtain an amorphous integrated inductor.

[0025] Another aspect of the present invention provides an amorphous one-piece molded inductor based on ultra-low pressure molding, which is manufactured using the above-mentioned method for manufacturing an amorphous one-piece molded inductor based on ultra-low pressure molding.

[0026] To facilitate understanding of the present invention, several embodiments of the present invention are provided below. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive disclosure of the present invention.

[0027] Example 1 The first embodiment of the present invention utilizes an ultra-low-pressure molding method for preparing an amorphous monolithic inductor. The coil used is Φ0.23*2.6*17.75Ts, with 17.75 turns. Ultra-low-pressure molding is performed using a T-shaped core at 70 MPa and a 180-second dwell time at 160°C. The resulting monolithic inductor, model MPAP0630SG220M, measures 7.1*6.5*3.0mm. The magnetic powder used is FeSiCr-D.

[0028] Example 2 The second embodiment of the present invention utilizes an ultra-low-pressure molding method for preparing an amorphous monolithic inductor. The coil used is Φ0.23*2.6*17.75Ts, with 17.75 turns. Ultra-low-pressure molding is performed using a T-shaped core at 70 MPa and a 160°C holding temperature for 180 seconds. The resulting monolithic inductor, model MPAP0630SG220M, measures 7.1*6.5*3.0mm. The magnetic powder used is carbonyl iron.

[0029] Example 3 The third embodiment of the present invention utilizes a method for fabricating an amorphous monolithic inductor using ultra-low pressure molding. The coil used is Φ0.23*2.6*17.75Ts, with 17.75 turns. Ultra-low pressure molding is performed using a T-shaped core at 70 MPa and a 160°C holding temperature for 180 seconds. The resulting monolithic inductor, model MPAP0630SG220M, measures 7.1*6.5*3.0 mm. The magnetic powder used is amorphous.

[0030] Comparative Example 1 The inductor manufacturing method in the first comparative example of the present invention utilizes a conventional pressing process. The coil used is Φ0.23*2.6*27.75Ts, with 27.75 turns. The molding process uses a conventional one-piece inductor molding process, with a pressing pressure of 600 MPa and a hold time of 3 seconds. The produced one-piece inductor model MPAP0630SG220M measures 7.1*6.5*3.0mm. The magnetic powder used is iron-silicon-chromium FeSiCr-D.

[0031] Comparative Example 2 The inductor manufacturing method in the second comparative example of the present invention utilizes a conventional molding process. The coil used is Φ0.23*2.6*27.75Ts, with 27.75 turns. The molding process uses a conventional one-piece inductor molding process, with a pressing pressure of 600 MPa and a hold time of 3 seconds. The produced one-piece molded inductor model MPAP0630SG220M measures 7.1*6.5*3.0mm. The magnetic powder used is carbonyl iron.

[0032] Comparative Example 3 The inductor manufacturing method in the third comparative example of the present invention utilizes a conventional molding process. The coil used is Φ0.23*2.6*27.75Ts, with 27.75 turns. The molding process uses a conventional one-piece inductor molding process, with a pressing pressure of 600 MPa and a hold pressure of 3 seconds. The produced one-piece molded inductor model MPAP0630SG220M has dimensions of 7.1*6.5*3.0mm. The magnetic powder used is amorphous powder.

[0033] In summary, the electromagnetic properties of the inductors obtained by the preparation methods of Examples 1-3 and Comparative Examples 1-3 are shown in Table 1, where DCR is the direct current resistance and L represents the inductance.

[0034] Table 1:

[0035] Table 1 shows that integrated inductors manufactured using conventional molding processes and the Tcore (T-shaped magnetic core) ultra-low pressure process (70 MPa, 160°C holding pressure for 180 seconds) meet the basic requirements of this inductor model. Integrated inductors manufactured using the ultra-low pressure molding process, with a high-pressure sintered core, exhibit higher magnetic permeability, allowing for fewer coil turns and significantly reducing copper wire usage. Integrated inductors manufactured using amorphous powder have higher inductance than competing integrated inductor powders.

[0036] Further, by Figure 4 It can be seen that the loss of the integrated inductor prepared by amorphous powder is significantly lower than that of the inductor formed by alloy powder composed of iron silicon chromium powder and carbonyl iron powder, which is reduced by at least 30%.

[0037] In summary, the method for preparing an amorphous one-piece molded inductor based on ultra-low pressure molding in the above-mentioned embodiments of the present invention adopts an amorphous powder with lower loss and higher magnetic permeability to mold an one-piece inductor at ultra-low pressure. On the one hand, the use of low-loss, high-magnetic-permeability amorphous powder greatly reduces the loss of the molded inductor and improves the efficiency of the inductor compared to conventional alloy powder molding of the one-piece inductor; on the other hand, ultra-low pressure molding reduces the deformation of the copper wire and the risk of short circuit between turns of the copper wire due to high voltage, and also avoids the risk of open circuit caused by high voltage at the copper wire solder joint, thereby improving the reliability of the one-piece inductor; and solves the technical problem in the prior art that high-voltage molded inductors easily damage the coil insulation layer and cause short circuits.

[0038] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0039] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be determined by the appended claims.

Claims

1. A method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding, characterized in that: include: Obtaining the prepared amorphous powder and pressing it to obtain a dense amorphous T-shaped magnetic core; The amorphous T-shaped core is wound and welded to form a terminal on the wound core to obtain a coil-amorphous core. The welded coil-amorphous core is placed in a forming mold and filled with powder and pressed at low pressure to obtain the inductor body. Performing a spray-coating anti-rust treatment on the inductor body to obtain a prefabricated inductor; The prefabricated inductor is removed from its legs to obtain an amorphous integrally formed inductor.

2. The method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding according to claim 1, characterized in that: In the step of obtaining the prepared amorphous powder, the preparation method of the amorphous powder includes: Obtaining an amorphous powder, and passivating, coating, and granulating the amorphous powder to obtain a prepared amorphous powder; Among them, the coating method adopts magnetic powder glue coating, and the component addition amount of magnetic powder glue includes 2%-5% of magnetic powder and 40%-60% of silicone resin. The viscosity of the magnetic powder glue is 100pa*s-500pa*s.

3. The method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding according to claim 2, characterized in that: The magnetic powder adhesive coating adopts explosion-proof spray granulation equipment for granulation. The granulated powder is amorphous powder with a particle size of 200 mesh to 400 mesh and a fluidity of 35s±5s.

4. The method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding according to claim 1, characterized in that: The welded coil-amorphous core is placed in a forming mold for powder filling and low-pressure pressing to obtain the inductor body. The low-pressure pressing pressure is 60Mpa-80Mpa, the pressing temperature is 160°C, and the pressure is maintained for 60s-180s.

5. The method for preparing an amorphous integrally formed inductor based on ultra-low pressure molding according to claim 2, characterized in that: The magnetic permeability of the amorphous powder is 40H / m-60H / m, and the DC bias capability is 100 Oe.

6. An amorphous one-piece molded inductor based on ultra-low pressure molding, characterized in that: The inductor is manufactured by the method for manufacturing an amorphous integrally formed inductor based on ultra-low pressure molding according to any one of claims 1 to 5.

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