Capillary arrangement type heat dissipation structure for power device and preparation method of capillary arrangement type heat dissipation structure

Abstract

The invention discloses a capillary arrangement type heat dissipation structure for a power device and a preparation method, the capillary arrangement type heat dissipation structure comprises a heat dissipation structure body, a plurality of capillary airflow micro-channels penetrating through the heat dissipation structure body are regularly arranged in the heat dissipation structure body, one side or two sides of the heat dissipation structure body are provided with air ports, and the air ports are communicated with an external air source. And gas enters the capillary airflow micro-channel through the gas port. The preparation method of the heat dissipation structure comprises the following steps: selecting a foil sheet meeting performance requirements and processing the foil sheet; the material foils are welded to the base body layer by layer through an ultrasonic welding head; the foil sheets stacked to a certain height are subjected to milling and material cutting treatment, and a preset capillary airflow micro-channel is machined; the material foil continues to be welded to the machined capillary airflow micro-channel through the ultrasonic welding head; repeating the steps until the heat dissipation structure is formed; and processing the processed heat dissipation structure, and carrying out performance monitoring. The heat dissipation structure is simple in structure, high in heat dissipation efficiency, compact in structure and low in manufacturing cost.

Description

Technical Field

[0001] The present invention relates to the technical field of heat dissipation of power devices, and in particular to a capillary arrangement type heat dissipation structure for power devices and a preparation method thereof. Background Art

[0002] With the rapid development of modern electronic technology, power devices such as insulated gate bipolar transistors (IGBTs) and power MOSFETs are increasingly used in many fields such as power systems, industrial automation, and new energy vehicles. These power devices generate a lot of heat during operation. If the heat cannot be dissipated in a timely and effective manner, the junction temperature of the device will increase, thereby affecting its performance, reliability, and service life. For example, excessively high junction temperature will increase the on-resistance of the power device, slow down the switching speed, and reduce the breakdown voltage. In severe cases, it may even cause thermal breakdown failure of the device, causing failure of the entire electronic system.

[0003] Traditional heat dissipation methods include natural convection, air cooling, and water cooling. Ordinary natural convection heat dissipation efficiency is extremely low and it is difficult to meet the heat dissipation requirements of high-power devices. Although air cooling has the advantages of simple structure and low cost, its heat dissipation capacity has gradually reached its limit when facing high-power density power devices or extremely small electronic components. The heat dissipation efficiency of water cooling is relatively high, but there are problems such as complex system, risk of leakage, and high maintenance cost. In addition, as power devices develop towards miniaturization and high power density, higher requirements are placed on the heat dissipation performance, volume, weight, and reliability of the heat dissipation structure. Therefore, the development of a new type of efficient, compact and reliable heat dissipation structure is of great significance to the further development of power devices. Summary of the invention

[0004] In order to overcome the above problems existing in the prior art, the present invention proposes a capillary arrangement type heat dissipation structure for power devices and a preparation method thereof.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a capillary arrangement heat dissipation structure for power devices, comprising a heat dissipation structure body, wherein a plurality of capillary airflow microchannels penetrating the heat dissipation structure body are regularly arranged inside the heat dissipation structure body, and the center distance between adjacent capillary airflow microchannels is 1-5mm. One side or both sides of the heat dissipation structure body are provided with air ports, and the air ports are connected to an external air source, and the gas enters the capillary airflow microchannels through the air ports.

[0006] In the above-mentioned capillary arrangement heat dissipation structure for power devices, the cross-sectional shape of the capillary airflow microchannel includes but is not limited to circular, square, and rectangular.

[0007] In the above-mentioned capillary arrangement heat dissipation structure for power devices, the diameter of the air port is 2-6 mm.

[0008] In the above-mentioned capillary arrangement heat dissipation structure for power devices, the heat dissipation structure body is provided with thermal conductive silicone grease on the surface in direct contact with the power device.

[0009] The above-mentioned capillary arrangement heat dissipation structure for power devices is made of a metal material with a purity greater than or equal to 99.9%.

[0010] A method for preparing a capillary arrangement type heat dissipation structure for a power device, used for preparing the above heat dissipation structure, specifically comprising: Step 1, material preparation: selecting a metal foil or a non-metal foil that meets the performance requirements and processing the metal foil or the non-metal foil; Step 2, using an ultrasonic welding head to apply pressure and ultrasonic vibration to weld the material foil selected in step 1 layer by layer on the substrate; Step 3, construction of capillary airflow microchannels: milling and cutting the foils stacked to a certain height to form a preset capillary airflow microchannel; Step 4, continue to weld the material foil to the processed capillary airflow microchannel through the ultrasonic welding head; Step 5, repeating steps 1-4 until a heat dissipation structure containing capillary airflow microchannels is formed; Step 6: grinding and polishing the processed heat dissipation structure containing the capillary airflow microchannels to prevent oxidation, and performing performance monitoring.

[0011] In the above-mentioned method for preparing a capillary arrangement heat dissipation structure for power devices, the thickness of the metal material foil in step 1 ranges from 50 μm to 200 μm.

[0012] In the above-mentioned method for preparing a capillary arrangement heat dissipation structure for power devices, the ultrasonic vibration frequency in step 2 is 20 kHz and the pressure range is 2000 MPa-5000 MPa.

[0013] In the above-mentioned method for preparing a capillary arrangement heat dissipation structure for power devices, in step 2, adjacent metal foils are misaligned, and in the horizontal direction, the metal foil on one side is misaligned with the same end of the metal foil on the other side by a certain distance, and the misalignment distance is 0.1-0.5mm.

[0014] The beneficial effects of the present invention are that the heat dissipation structure of the present invention has a simple structure, high heat dissipation efficiency, a compact structure and low preparation cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1It is a schematic diagram of the heat dissipation structure of the present invention; Figure 2 is a perspective view of the heat dissipation structure of the present invention; Figure 3 It is a process flow chart of the heat dissipation structure preparation process of the present invention; Figure 4 Schematic diagram of ultrasonic additive and subtractive material integrated manufacturing equipment in an embodiment of the present invention; Figure 5 Schematic diagram of a workbench in an embodiment of the present invention, wherein (a) is a plan view of the workbench; and (b) is a perspective view of the workbench.

[0016] Among them, 1. heat dissipation structure body, 2. capillary airflow microchannel, 3. cutting unit, 4. foil raw material wheel, 5. tensioning wheel, 6. limiting wheel, 7. transmission wheel, 8. transmission card, 9. workbench, 10. main shaft, 11. ultrasonic welding unit. DETAILED DESCRIPTION

[0017] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0018] like Figure 1-2 As shown, this embodiment discloses a capillary arrangement heat dissipation structure for power devices, including a heat dissipation structure body 1, wherein a plurality of capillary airflow microchannels 2 penetrating the heat dissipation structure body are regularly arranged inside the heat dissipation structure body 1, and the center distance between adjacent capillary airflow microchannels 2 is 1-5mm. An air port is provided on one side or both sides of the heat dissipation structure body 1, and the air port is connected to an external air source, which can provide a normal temperature or low temperature gas, such as air or nitrogen. The gas enters the capillary airflow microchannel array through the air port, exchanges heat with the channel wall during the flow in the microchannel, and is discharged from the air port after absorbing heat, thereby realizing heat dissipation of the power device.

[0019] In this embodiment, the cross-sectional shape of the capillary flow microchannel includes, but is not limited to, circular, square, and rectangular. Preferably, the cross-sectional shape is circular, the diameter is 0.1-1 mm, and the diameter of the air port is 2-6 mm.

[0020] The upper surface of the entire heat dissipation structure is used to directly contact the power device. The contact thermal resistance is reduced by applying thermal conductive silicone grease to ensure that heat can be efficiently transferred from the power device to the heat dissipation structure.

[0021] The heat dissipation structure uses a variety of metal foils with different characteristics, or non-metallic materials as the basic materials for manufacturing the heat dissipation structure. For example, copper sheets with a purity of more than 99.9% are selected as the main building material of the cooling pipe due to their excellent thermal conductivity and the ability to quickly conduct heat during the cooling process, ensuring that heat can be efficiently transferred within the cooling plate.

[0022] Another material is a metal with high strength and excellent corrosion resistance, such as 6061 aluminum. As a lightweight metal material, aluminum can ensure the thermal conductivity of the cooling plate while meeting the advantages of small mass. The thickness of the metal foil is controlled between 50μm-200μm, and this thickness range is determined through a large number of experiments and theoretical analysis. This range can not only ensure reliable welding between metal sheets during ultrasonic additive manufacturing, but also enable the final cooling plate to meet the comprehensive requirements of thickness and weight in different application scenarios.

[0023] This embodiment also discloses a method for preparing a capillary arrangement type heat dissipation structure for a power device, which is used to prepare the above heat dissipation structure, such as Figure 3 As shown, specifically including: Step 1, material preparation: select metal foil or non-metal foil that meets the performance requirements and process the metal foil or non-metal foil.

[0024] Due to the wide range of applications of ultrasonic welding heads, this embodiment can use a variety of metal foils with different characteristics, or non-metallic materials as the basic materials for manufacturing cooling plates. For example, a copper sheet with a purity of more than 99.9%. Copper is selected as the main construction material of the cooling pipe due to its excellent thermal conductivity and the ability to quickly conduct heat during the cooling process, ensuring that heat can be efficiently transferred within the cooling plate. Another material is a metal with high strength and excellent corrosion resistance, such as 6061 aluminum. As a lightweight metal material, aluminum can ensure the thermal conductivity of the cooling plate while meeting the advantages of small mass. The thickness of the metal foil is controlled between 50μm-200μm, and this range is determined through a large number of experiments and theoretical analysis. This range can not only ensure a reliable welding effect between metal sheets during ultrasonic additive manufacturing, but also enable the final manufactured cooling plate to meet the comprehensive requirements of thickness and weight in different application scenarios.

[0025] Before manufacturing, the selected metal foil and other materials are pretreated. First, a suitable chemical cleaning method is used to remove oil stains on the surface of the metal foil. For example, an organic solvent (such as ethanol, acetone, etc.) is used to soak the metal foil to dissolve and remove grease pollutants on the surface. This ensures that the surface of the metal foil is clean and free of impurities, providing good surface conditions for the subsequent ultrasonic welding process, thereby ensuring the welding quality and the overall performance of the cooling plate.

[0026] Step 2: Using an ultrasonic welding head to apply pressure and ultrasonic vibration, the material foil selected in step 1 is welded layer by layer on the substrate.

[0027] After fixing the substrate to be welded (which can be an aluminum or copper substrate), use a high-frequency ultrasonic welding head (usually with a frequency of 20kHz and a pressure range of 2000MPa-5000MPa) to weld metal foils and other materials layer by layer on the substrate using the rolling welding method. The motion trajectory and welding starting position of the ultrasonic welding head are controlled by a pre-set program to produce a specific misalignment between adjacent metal foils. Specifically, in the horizontal direction, the metal foil on one side is misaligned with the same end of the metal foil on the other side by a certain distance, and the misalignment distance is usually set between 0.1-0.5mm. For example, during the manufacturing process, a copper sheet on one side is welded to the underlying substrate. When welding the copper sheet on the other side, its position is precisely controlled by the CNC system so that one end is misaligned by 0.3mm relative to the same end of the first layer of copper sheet. This design allows the junction of the two metal foils to be extruded and formed due to the energy generated by ultrasonic vibration, and then welded into a complete metal block.

[0028] Under the vibration of the ultrasonic horn, the metal foil is welded layer by layer to the metal foil strip that has been welded to the substrate until it is stacked to a specified height.

[0029] Step 3, construction of capillary airflow microchannels: the foils stacked to a certain height are subjected to milling processing to process the preset capillary airflow microchannels.

[0030] Then, a CNC machining center is used to mill and reduce the required micro-pores on the foil blocks stacked to a specified height.

[0031] Step 4: Continue to weld the material foil to the processed capillary airflow microchannel by using the ultrasonic welding head.

[0032] Step 5, repeat steps 1-4 until a heat dissipation structure containing capillary airflow microchannels is formed.

[0033] Step 6: grinding and polishing the processed heat dissipation structure containing the capillary airflow microchannels to prevent oxidation, and performing performance monitoring.

[0034] The cooling plate is subjected to certain surface treatment. High-precision grinding equipment is used to grind the surface of the cooling plate to remove tiny protrusions and flaws generated during the welding process to ensure that the surface of the cooling plate is flat and smooth. Subsequently, chemical nickel plating or electroplating nickel plating is used to perform a certain degree of anti-oxidation treatment on the surface to ensure the thermal conductivity of the material itself. At the same time, advanced air tightness testing equipment (such as helium mass spectrometer leak detector) is used to conduct strict air tightness testing on the capillary pipes or capillary micropores of the cooling plate. The test pressure is set between 1MPa-5MPa to ensure that there are no leaks in the capillary pipes and to ensure the heat dissipation reliability and stability of the cooling plate in actual applications.

[0035] In addition, comprehensive performance tests are carried out on the cooling plates, including thermal conductivity tests and compressive strength tests. The manufacturing process is optimized and adjusted based on the test results to meet the stringent requirements of high-performance heat dissipation components in the fields of electronic equipment, aerospace, energy, etc.

[0036] In this embodiment, the heat dissipation structure can also be processed by ultrasonic additive manufacturing equipment. The ultrasonic additive manufacturing equipment can be any equipment on the market that can implement the preparation method of this embodiment. The following ultrasonic additive manufacturing equipment can also be used for processing. The specific structure of the ultrasonic additive manufacturing equipment is as follows: Figure 4 As shown. Figure 4 As shown, it includes a main frame, a main shaft 10, an additive structure, a subtractive structure, and a control module. The main shaft 10 is vertically mounted on one side of the main frame, the subtractive structure is mounted on the main shaft 10 and can move up and down along the main shaft, the additive structure is mounted on the right side of the main shaft, and a workbench 9 that can move in the x-axis and y-axis directions is provided on the upper surface of the main frame. The subtractive structure includes a milling tool, and the control module is used to receive a three-dimensional model of a part and control the operation of the additive structure and the subtractive structure.

[0037] The main frame, as the basic support structure of the milling tool, is made of high-strength metal materials and has sufficient rigidity and stability to ensure that the equipment will not be significantly deformed during the manufacturing process. The precisely constructed z-axis guide system inside the main frame provides high-precision guidance and support for the subsequent movement of the spindle.

[0038] As the key moving part of the milling tool, the spindle is manufactured using precision machining technology, and the surface is specially treated (such as quenching, grinding, etc.) to improve hardness and surface finish, ensuring accuracy and stability during high-speed rotation and frequent axial movement. The spindle is compatible with a variety of standard milling tools, and a reliable connection with the milling tool is achieved through high-precision taper matching (such as common BT, CAT and other taper systems). The spindle is designed with a cooling channel inside, which can introduce coolant during the working process to effectively take away the heat generated by high-speed rotation and cutting, and prevent the spindle from being deformed or damaged due to overheating. The spindle is connected to the z-axis motor through a high-precision ball screw nut pair. Under the precise control of the control module, the z-axis motor drives the spindle to achieve fast and precise movement in the z-axis direction, and the positioning accuracy can reach ±0.005mm or even higher.

[0039] The spindle plays a vital role in the working process of the milling tool. Its functions cover tool installation (different types of milling cutters, such as end mills, face mills, ball-end mills, etc.), rotation drive (the motor speed and torque are transmitted to the spindle through belt drive, gear drive or direct drive, and the spindle then accurately transmits the rotational motion to the milling cutter), motion control (the spindle can not only realize rotational motion, but also move along the z-axis direction within a certain range, so as to realize the cutting process of the workpiece in different depth directions. This z-axis motion control is combined with the movement of the worktable in the x-axis and y-axis directions, so that the milling cutter can cut the workpiece according to the predetermined processing path in three-dimensional space), precision assurance (the high-precision spindle can ensure that the milling cutter's blade always moves on a precise circle during the rotation process, so that the cutting thickness is uniform and consistent, reducing processing errors), power transmission (the spindle can effectively transmit the power and torque output by the motor to the milling cutter, and provide appropriate power according to processing requirements. Milling machine spindles of different specifications and models have different power and torque characteristics to meet various types and scales of processing tasks) and many other aspects.

[0040] 9 is a workbench. The workbench below the spindle can move freely in the x-axis and y-axis directions. Its moving range covers the entire workbench surface, providing a wide operating space for the processing of parts. The workbench 9 under the spindle is also made of high-strength metal materials, and its surface is finely ground to ensure the flatness and roughness requirements. The workbench is connected to the x-axis and y-axis motors through linear guides to form a high-precision planar motion system. Under the coordinated control of the control system, the x-axis and y-axis motors can drive the workbench to achieve fast and accurate positioning and movement in the x-axis and y-axis directions. The movement speed can be adjusted according to the processing requirements, and the maximum speed can reach several meters per minute. The positioning accuracy can also reach ±0.005mm level. The size of the workbench is determined according to the equipment design specifications. Generally, the workbench size of large-scale equipment can reach several square meters, which can carry large-sized and heavy workpieces for processing.

[0041] In a specific embodiment, the workbench is provided with heating wires arranged horizontally and vertically, such as Figure 5 As shown in the figure, these heating wires are connected to the control center module through PLC, which can provide a certain preset temperature for the welding process to meet the processing requirements of more materials. The main frame of the entire processing platform serves as the basic supporting structure of the ultrasonic welding manufacturing equipment. It not only provides a stable installation platform for the spindle and the workbench, but also bears the weight of the entire equipment and various forces generated during the working process.

[0042] In this embodiment, the control module uses an advanced industrial control computer or a programmable logic controller (PLC) as the core control unit, and is equipped with a high-precision motion control card and a sensor interface card. Before the manufacturing process begins, the operator imports the three-dimensional model of the part into the control module, and selects different types of foils according to the required part structure. Different foils select appropriate welding parameters such as welding pressure, ultrasonic frequency, ultrasonic amplitude, welding speed, and workbench temperature. During the manufacturing process, the control module monitors various state parameters of the equipment in real time, such as spindle position, workbench position, welding head vibration parameters, milling force, temperature, etc., and dynamically adjusts the operating state of the equipment according to these parameters. For example, in the process of additive welding, if the welding quality is detected to be abnormal (such as insufficient welding strength, discontinuous welds, etc.), the control module will immediately adjust the welding parameters (such as increasing vibration energy, adjusting welding pressure, etc.); in the process of subtractive milling, if the tool wear exceeds the set threshold, the control module will automatically replace the tool or adjust the milling parameters to ensure the processing accuracy. At the same time, the control module also has a human-machine interactive interface, through which operators can view the progress of the manufacturing process and equipment status parameters in real time, and can manually intervene in the manufacturing process as needed, such as pausing, adjusting parameters, switching processing modes, etc. Through this control module, seamless switching and collaborative work of additive and subtractive manufacturing processes on the same equipment are achieved, greatly improving manufacturing efficiency and part quality.

[0043] In this embodiment, the additive structure includes a cutting unit 3, a foil feeding unit, and an ultrasonic welding unit 11. The cutting unit 3 is equipped with a high-strength hardened steel blade for cutting foil. The foil feeding unit is used to continuously provide metal or non-metal foil to the ultrasonic welding unit. The foil feeding unit includes a foil raw material wheel 4, a tensioning wheel 5, a limiting wheel 6, a transmission wheel 7, and a transmission card 8. The foil raw material wheel 4 is provided with a buckle, which can be used to clamp the raw material foil roll, and the raw material foil is continuously transported outward from here; a tension sensor is provided in the tensioning wheel to monitor the tension of the foil in real time and feed back the information to the interface of the control module; the limiting wheel 6 is used to guide the foil into the conveying wheel and limit the outflow of the foil; the conveying wheel 7 is used to control the feeding speed of the foil, and the conveying wheel is driven to rotate by a motor, and the motor is connected to the control module. The operator can change the feeding speed of the foil through the control module. The conveying wheel is embedded with polyurethane material, which is a polymer material with high friction, high wear resistance and high elasticity, which is convenient for clamping the foil and conveying it to a predetermined position; the conveying card 8 is used to accurately deliver the foil to the bottom of the ultrasonic welding unit.

[0044] In this embodiment, the structure of the ultrasonic welding unit 11 specifically includes a connecting plate, an ultrasonic transducer, an ultrasonic amplitude transformer, and an ultrasonic welding head. The connecting plate is connected to the main shaft 10, the ultrasonic transducer is located on both sides of the ultrasonic amplitude transformer, and the ultrasonic welding head is located in the middle of the ultrasonic amplitude transformer. The ultrasonic welding head is made of high-wear-resistant materials such as tungsten steel, or a high-hardness coating is formed by laser cladding, such as cladding a tungsten-chromium alloy coating on the surface of a titanium alloy. The surface has a certain roughness, and the surface roughness Ra=25μm.

[0045] In the system of the present invention, the additive and subtractive structures realize a close collaborative working relationship through the spindle. The entire additive structure is installed on the right side of the spindle and can move with the spindle in the z-axis direction. At the same time, the movement of the worktable in the x-axis and y-axis directions can accurately position the parts under the ultrasonic welding assembly to realize additive welding processing of the parts, and at the same time, the processed workpiece can be moved under the spindle for corresponding milling and subtractive operations.

[0046] During the additive manufacturing process, the foil is accurately transported from the foil raw material wheel 4 to the working area below the ultrasonic welding head through the tensioning wheel 5, the limiting wheel 6, the transmission wheel 7, and the transmission card 8. Under the control of the control module, the transmission wheel 7 can accurately control the feeding speed and feeding amount of the foil according to the preset welding parameters (such as welding speed, welding pressure, foil thickness, etc.). After receiving the high-frequency ultrasonic vibration signal, the ultrasonic welding head transfers the vibration energy to the foil, so that the foil is solid-state welded with the welded part (such as the substrate or the previous welding layer) under the combined action of pressure and ultrasound. During the welding process, the parameters such as the vibration frequency, amplitude and applied pressure of the welding head are monitored and adjusted in real time by the control system to ensure the stability and consistency of the welding quality. As the welding process continues, the metal foil is accumulated layer by layer, gradually forming a three-dimensional part entity. After each layer of welding is completed, according to the part design requirements, the control module can selectively pause the welding process, start the milling operation, perform fine processing on the current layer, and then continue to weld the next layer, and so on, until the additive manufacturing process of the entire part is completed.

[0047] When subtractive manufacturing (milling) is required, the control module drives the milling tool to move in the z-axis direction and positions the milling tool (such as milling cutter, drill, boring tool, etc.) installed on the spindle above the part to be processed. Driven by the x-axis and y-axis motors, the worktable moves the part to the processing path of the milling tool. During the milling process, the milling tool rotates at high speed (the speed can be adjusted from thousands of revolutions per minute to tens of thousands of revolutions per minute according to the processing material and tool type). At the same time, according to the preset milling path and processing parameters (such as feed speed, cutting depth, cutting width, etc.), the worktable and the milling tool move in coordination to achieve precise milling of the part. Through multiple milling operations in different directions and depths, it is possible to remove excess material on the part to form various complex shape features, such as internal cavities, external contours, threads, keyways, etc., and at the same time, the surface of the part is finely trimmed to achieve the dimensional accuracy and surface roughness required by the design.

[0048] The above embodiments are only exemplary embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art may make various modifications or equivalent substitutions to the present invention within the essence and protection scope of the present invention, and such modifications or equivalent substitutions shall also be deemed to fall within the protection scope of the present invention.

Claims

1. A capillary arrangement heat dissipation structure for power devices, characterized in that: It includes a heat dissipation structure body, wherein a plurality of capillary airflow microchannels penetrating the heat dissipation structure body are regularly arranged inside the heat dissipation structure body, and the center distance between adjacent capillary airflow microchannels is 1-5mm. An air port is arranged on one side or both sides of the heat dissipation structure body, and the air port is connected to an external air source, and the gas enters the capillary airflow microchannel through the air port.

2. The capillary arrangement heat dissipation structure for power devices according to claim 1, characterized in that: The cross-sectional shape of the capillary airflow microchannel includes but is not limited to circular, square, and rectangular.

3. The capillary arrangement heat dissipation structure for power devices according to claim 1, characterized in that: The diameter of the air port is 2-6 mm.

4. The capillary arrangement heat dissipation structure for power devices according to claim 1, characterized in that: The surface of the heat dissipation structure body that directly contacts the power device is provided with thermal conductive silicone grease.

5. The capillary arrangement heat dissipation structure for power devices according to claim 1, characterized in that: The heat dissipation structure is made of a metal material with a purity greater than or equal to 99.9%.

6. A method for preparing a capillary arrangement heat dissipation structure for a power device, characterized in that: Used to prepare the heat dissipation structure according to any one of claims 1 to 5, specifically comprising: Step 1, material preparation: selecting a metal foil or a non-metal foil that meets the performance requirements and processing the metal foil or the non-metal foil; Step 2, using an ultrasonic welding head to apply pressure and ultrasonic vibration to weld the material foil selected in step 1 layer by layer on the substrate; Step 3, construction of capillary airflow microchannels: milling and cutting the foils stacked to a certain height to form a preset capillary airflow microchannel; Step 4, continue to weld the material foil to the processed capillary airflow microchannel through the ultrasonic welding head; Step 5, repeating steps 1-4 until a heat dissipation structure containing capillary airflow microchannels is formed; Step 6: grinding and polishing the processed heat dissipation structure containing the capillary airflow microchannels to prevent oxidation, and performing performance monitoring.

7. The method for preparing a capillary arrangement heat dissipation structure for power devices according to claim 6, characterized in that: In the step 1, the thickness of the metal material foil is in the range of 50 μm to 200 μm.

8. The method for preparing a capillary arrangement heat dissipation structure for a power device according to claim 6, characterized in that: In step 2, the ultrasonic vibration frequency is 20 kHz and the pressure range is 2000 MPa-5000 MPa.

9. The method for preparing a capillary arrangement heat dissipation structure for power devices according to claim 6, characterized in that: In step 2, adjacent metal foils are dislocated. In the horizontal direction, the metal foil on one side is dislocated with the same end of the metal foil on the other side by a certain distance, and the dislocation distance is 0.1-0.5 mm.

Images