Composite material heat dissipating electronic module forming mold and method

Abstract

The present application relates to a kind of composite material heat dissipation electronic module forming die and method, forming die includes main mould, solder paste printing tooling, welding tooling;Method includes: mold cleaning and metal piece pre-embedded;Lay inner skin carbon fiber layer, adhesive film, foam layer, outer skin carbon fiber layer;Solidification forming, demolding, hole making obtain carbon fiber structural component combination;Print lead-tin solder paste;Through welding tooling, uniform temperature plate is welded to carbon fiber structural component combination.The present application is pre-embedded by metal heat dissipation conductive insert, then co-curing with carbon fiber structure body by forming method, realizes the synchronous cementation of metal heat dissipation conductive insert in the carbon fiber structure body forming process, utilizes the electrostatic transmission function of ground boss in metal heat dissipation conductive insert, solves the problem that composite material electronic module electrical ground is difficult to realize;Through the use of solder paste printing tooling and welding tooling, realize the accurate welding of uniform temperature plate on metal heat dissipation conductive insert.

Description

Technical Field

[0001] This invention belongs to the field of radar electronic equipment processing and manufacturing, and relates to a method for processing and manufacturing composite material electronic modules, which is mainly used to manufacture radar electronic modules that require lightweight and efficient heat dissipation. Background Technology

[0002] Electronic modules are a major component of radar equipment. They primarily provide installation support interfaces and protection for electrical units within radar systems such as signal processing and power supply, and have functions such as environmental protection, load bearing, heat dissipation, and electrical grounding.

[0003] Currently, to meet the lightweight requirements of radar equipment, the materials used in electronic module structures have shifted from traditional aluminum alloys to composite materials. Advanced composite electronic modules, represented by carbon fiber, are lightweight and high-strength. However, the poor thermal and electrical conductivity of carbon fiber composites makes heat dissipation and electrical grounding difficult. Although heat dissipation and electrical grounding can be achieved through fan cooling and the addition of grounding cables, these methods require additional components such as fans and cables, increasing the module's weight and size, and failing to meet the high integration, miniaturization, and stringent lightweight requirements of the module.

[0004] A certain product's radar electronic module has external dimensions of 180mm×120mm×80mm, and there are 10 of them. The design requirements are that the weight of each module housing should be controlled within 0.5kg, and that the module's operating temperature should not exceed 70℃ under a heat flux density of 3W / cm2, and the lap resistance of the module's mounting surface should not exceed 2.5mΩ. The existing heat dissipation and grounding design methods can no longer meet the requirements of efficient heat dissipation and electrical grounding for composite material electronic modules. Summary of the Invention

[0005] The technical problem to be solved by this invention is: The purpose of this invention is to solve the problems of high difficulty in heat dissipation and electrical grounding of existing composite material electronic modules. This invention achieves efficient heat dissipation of the composite material electronic module by pre-embedding a metal heat-dissipating conductive insert and co-curing it with a carbon fiber structure, followed by lead-tin soldering to weld a heat spreader to the metal heat-dissipating conductive insert. Furthermore, by setting a grounding boss in the metal heat-dissipating conductive insert, static electricity is transferred through the electrical contact between the boss's mounting surface and the device's ground plane after screw tightening, thus achieving electrical grounding of the composite material electronic module. Finally, a new method for manufacturing composite material heat-dissipating electronic modules is obtained, satisfying the requirements of lightweight design, efficient heat dissipation, and electrical grounding.

[0006] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: A composite material heat dissipation electronic module molding die, wherein the electronic module is composed of a carbon fiber structure, a metal heat dissipation and conductive insert and a heat spreader, and the metal heat dissipation and conductive insert is composed of a heat dissipation tooth surface, a cold plate, heat dissipation blocks on the left and right sides and a grounding boss; characterized in that it includes a main mold, a solder paste printing fixture and a welding fixture. The main mold is used for thermoforming carbon fiber structures and metal heat dissipation and conductive inserts. It consists of a working platform and a forming surface located on the working platform. The working platform is a cuboid structure with dimensions larger than the electronic module. The forming surface is a stepped rectangular structure, composed of a first-order rectangle and a second-order rectangle. The length and width of the first-order rectangle are consistent with the length and width of the outer surface of the electronic module, respectively. The geometry of the second-order rectangle is consistent with the shape of the inner surface of the electronic module. The solder paste printing fixture is a rectangular structure with a boss, consisting of a boss and a plate. The geometric dimensions of the boss are consistent with the shape of the rectangular groove on the metal heat dissipation and conductive insert. The top surface of the boss has a mesh-like hollow structure for solder paste printing pre-fabrication. The length and width of the plate are 1mm smaller than the length and width of the inner surface of the electronic module, respectively. The plate has three rectangular grooves in the middle, and the center of the rectangular grooves is consistent with the center of the boss. The bottom surface of the rectangular grooves has a mesh-like hollow structure. The welding fixture consists of a base plate, a support column, a top plate, and set screws. The base plate fixture is a hollow rectangular structure and is connected to the top plate through the support column. The top plate is a rectangular structure with three M5 threaded holes designed at the corresponding positions of the heat spreader plate for the installation and tightening of the set screws.

[0007] A further technical solution of the present invention: The top surface of the second-order rectangular body is provided with a circular blind hole for precise positioning of the metal heat dissipation and conductive insert on the main mold.

[0008] A further technical solution of the present invention: the wall thickness of the top surface of the boss is consistent with the thickness of the pre-made solder paste 30.

[0009] A further technical solution of the present invention: the top surface wall thickness of the boss, i.e., the thickness t of the pre-applied solder paste, satisfies the following: Where l: length of the rectangular groove, unit: mm; w: width of the rectangular groove, unit: mm; t1: width of the longitudinal and transverse ribs on the bottom surface of the rectangular groove, unit: mm; t2: width of the hollowed-out part on the bottom surface of the rectangular groove, unit: mm; t3: actual thickness of the pre-made solder paste after high-temperature welding, unit: mm.

[0010] A further technical solution of the present invention: the flat plate is designed with through holes around its four sides for precise positioning of the solder paste printing fixture on the electronic module during solder paste printing.

[0011] A further technical solution of the present invention: the length and width of the rectangular groove are 1mm smaller than the length and width of the boss.

[0012] A further technical solution of the present invention: the bottom surface of the rectangular groove is a mesh-like hollow structure, which is composed of longitudinal and transverse ribs and hollow parts, wherein the width of all longitudinal and transverse ribs is the same, and the width of the hollow parts is the same.

[0013] A further technical solution of the present invention: the length and width dimensions are 20mm larger than the length and width of the outer surface of the electronic module, and the thickness is 5mm. The bottom plate is designed with through holes around its perimeter for connecting the bottom plate to the support column.

[0014] A further technical solution of the present invention: the support column is a cylindrical structure with a diameter of φ8 and a height that is 5mm greater than the height of the electronic module. An M4 threaded hole is designed at the center of each end of the support column for connecting the base plate, the top plate and the support column.

[0015] A method for preparing a composite material heat dissipation electronic module, characterized by using the aforementioned composite material heat dissipation electronic module molding die; the steps are as follows: Step 1: Clean the main mold with alcohol, let it air dry at room temperature, and then apply release agent to the surface at least twice, with an interval of at least 10 minutes between each application. Step 2: Place the metal heat dissipation and conductive insert at the corresponding position on the top surface of the second-order rectangle of the main mold; Step 3: Lay three layers of inner carbon fiber skin on the five surfaces of the main mold's second-order rectangular body: left, right, front, back, and top. The layering sequence is (±45° / 0° / 90°). Step 4: After laying the inner adhesive film layer, foam layer, and outer adhesive film layer on the left, right, front, and back surfaces of the main mold's second-order rectangular body, place the rectangular inserts into the corresponding positions of the foam layers. Step 5: Lay 6 layers of local carbon fiber at the flange of the metal heat dissipation and conductive insert and at 8 locations on the left and right heat dissipation blocks, with the layering sequence being [±45° / (0°90°) / ±45°]s; Step 6: Lay three layers of outer carbon fiber skin on the five surfaces of the main mold's second-order rectangular body: left, right, front, back, and top. The layering sequence is (90° / 0° / ±45°). Step 7: Make a vacuum bag, cure it in an autoclave, demold, mill the edges, and make holes to prepare a combination of carbon fiber structure and metal heat dissipation and conductive insert; Step 8: Place the solder paste printing fixture on the back of the metal heat dissipation and conductive insert, and position it with the metal heat dissipation and conductive insert through the φ5 through hole; Step 9: Using the mesh-like perforated structure of the solder paste printing fixture, prepare lead-tin pre-made solder paste 30 in the groove on the back of the metal heat dissipation and conductive insert. After the solder paste is pre-made, remove the solder paste printing fixture. Step 10: Place the three heat spreaders on the pre-made solder paste; Step 11: After the base plate of the welding fixture is connected to the support screw, place the combination of carbon fiber structure and metal heat dissipation and conductive insert on the base plate of the welding fixture, then connect the top plate of the welding fixture to the support screw, and finally pass the set screw through the top plate to press the combination of carbon fiber structure and metal heat dissipation and conductive insert to the heat spreader. Step 12: Place the combination of carbon fiber structure and metal heat dissipation and conductive insert, heat spreader and welding fixture into the oven, set the welding temperature, and perform lead-tin welding to obtain the electronic module.

[0016] The beneficial effects of this invention are as follows: This invention utilizes a molding method that involves pre-embedding a metal heat-dissipating and conductive insert before co-curing it with a carbon fiber structure. This method enables the simultaneous adhesive bonding and insertion of the metal heat-dissipating and conductive insert during the carbon fiber structure molding process. By leveraging the electrostatic transfer function of the grounding protrusion in the metal heat-dissipating and conductive insert, the invention solves the problem of difficult electrical grounding in composite electronic modules. Furthermore, the use of solder paste printing and welding fixtures enables precise post-welding of a heat spreader onto the metal heat-dissipating and conductive insert. The efficient convective heat dissipation capability of the heat spreader and the welded assembly of the metal heat-dissipating and conductive insert further addresses the heat dissipation challenge of composite electronic modules. Ultimately, this invention yields a novel molding and fabrication method for efficient heat dissipation and electrical grounding of composite electronic modules based on lightweight manufacturing. Attached Figure Description

[0017] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0018] Figure 1 Electronic module structure diagram.

[0019] Figure 2 Schematic diagram of a metal heat dissipation and conductive insert.

[0020] Figure 3 Main mold structure diagram.

[0021] Figure 4 Structural diagrams of the solder paste printing fixture: (a) 3D front view of the solder paste printing fixture; (b) 3D front view of the solder paste printing fixture; (c) Plan view of the solder paste printing fixture.

[0022] Figure 5 Welding fixture structure diagram.

[0023] Figure 6Diagrams illustrating the electronic module fabrication process: (d) Schematic diagram of carbon fiber structure forming; (e) Cross-sectional view of carbon fiber structure layup; (f) Schematic diagram of electronic module welding.

[0024] In the diagram, 1-forming mold; 2-electronic module; 3-carbon fiber structure; 4-metal heat dissipation and conductive insert; 5-heat spreader; 6-heat dissipation tooth surface in the metal heat dissipation and conductive insert; 7-cold plate of the metal heat dissipation and conductive insert; 8-heat dissipation blocks on the left and right sides of the metal heat dissipation and conductive insert; 9-grounding boss of the metal heat dissipation and conductive insert; 10-main mold; 11-solder paste printing fixture; 12-welding fixture; 13-working platform of the main mold; 14-first-order rectangle of the main mold; 15-second-order rectangle of the main mold; 16-bore portion of the solder paste printing fixture; 17-flat portion of the solder paste printing fixture; 18-flat portion of the solder paste printing fixture. 19 - Rectangular groove on the plate section; 20 - Longitudinal and transverse ribs of the rectangular groove structure; 21 - Hollowed-out portion of the rectangular groove structure; 22 - Base plate of the welding fixture; 23 - Support column of the welding fixture; 24 - Top plate of the welding fixture; 25 - Set screw of the welding fixture; 26 - Inner skin carbon fiber layer; 27 - Foam layer; 28 - Rectangular inlay; 29 - Partial carbon fiber layer; 30 - Outer skin carbon fiber layer; 10 - Lead-tin pre-made solder paste; t - Thickness of pre-made solder paste; l - Length of the rectangular groove structure; w - Width of the rectangular groove structure; t1 - Width of the longitudinal and transverse ribs in the rectangular groove structure; t2 - Width of the hollowed-out portion in the rectangular groove structure. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0026] This invention provides a composite material heat dissipation electronic module molding die 1. The electronic module 2 is composed of a carbon fiber structure 3, a metal heat dissipation and conductive insert 4, and a heat spreader 5, etc. The metal heat dissipation and conductive insert 4 is composed of a heat dissipation tooth surface 6, a cold plate 7, heat dissipation blocks 8 on both sides, and a grounding boss 9. The molding die 1 is composed of a main die 10, a solder paste printing fixture 11, a welding fixture 12, etc. The main die 10 is used for the thermoforming of the carbon fiber structure 3 and the metal heat dissipation and conductive insert 4, and is composed of a working platform 13 and a forming surface. The working platform 13 is a cuboid structure with a thickness of 25 μm. The length and width of the molded surface are 300mm and 150mm larger than the length and width of the outer surface of the electronic module 2, respectively. The molded surface is a stepped rectangular structure, consisting of a first-order rectangular body 14 and a second-order rectangular body 15. The thickness of the first-order rectangular body 14 is 20mm, and its length and width are the same as the length and width of the outer surface of the electronic module 2, respectively. The geometry of the second-order rectangular body 15 is the same as the shape of the inner surface of the electronic module 2. The top surface of the second-order rectangular body 15 is provided with 10 φ5 circular blind holes with a depth of 3mm, which are used for the precise positioning of the metal heat dissipation and conductive insert 4 on the main mold 10. The solder paste printing fixture 11 is a rectangular structure with a boss, consisting of a boss 16 and a flat plate 17. The geometric dimensions of the boss 16 are consistent with the shape of the rectangular groove on the metal heat dissipation and conductive insert 4. The top surface of the boss 16 has a mesh-like perforated structure for pre-printing solder paste. The wall thickness of the top surface is consistent with the thickness of the pre-printed solder paste 30, which is t. The flat plate 17 has a thickness of 5mm, and its length and width are 1mm smaller than the length and width of the inner surface of the electronic module, respectively. The platform structure 17 has 10 φ5 through holes around its perimeter for use during solder paste printing. The solder paste printing fixture 11 is precisely positioned on the electronic module 2. The platform structure 17 has three rectangular grooves 18 in the middle. The center of the rectangular grooves 18 is consistent with the center of the boss 16. The length and width of the rectangular grooves 18 are 1mm smaller than the length and width of the boss 16, respectively. The length is l and the width is w. The bottom surface of the rectangular grooves 18 is a mesh hollow structure, which consists of longitudinal and transverse ribs 19 and hollow parts 20. All longitudinal and transverse ribs 19 have the same width, which is t1. The width of the hollow parts 20 is the same, which is t2.The welding fixture 12 consists of a base plate 21, a support column 22, a top plate 23, and set screws 24. The base plate fixture 21 is a rectangular structure, with its length and width dimensions being 20mm larger than the length and width of the outer surface of the electronic module 2, respectively, and a thickness of 5mm. The base plate fixture 21 has four φ4.5 through holes around its perimeter for connecting to the support column fixture 22. The support column fixture 22 is a cylindrical structure with a diameter of φ8 and a height 5mm larger than the height of the electronic module 2. Each end of the support column fixture 22 has an M4 threaded hole at its center for connecting the base plate fixture 21, the top plate fixture 23, and the support column 22. The top plate fixture 23... Mount 23 is a rectangular structure with the same length and width as the base plate fixture 21, and a thickness of 5mm. The top plate fixture 23 has four φ4.5 through holes around its perimeter for connecting the top plate fixture 23 to the support column 22. The top plate fixture 23 has three M5 threaded holes at the corresponding positions of the heat spreader plate 5 for installing and tightening the set screws 24. The set screws 24 have an M5 diameter and a length that is 5mm longer than the height of the support column fixture 22. The set screws 24 pass through the M5 threaded holes on the top plate fixture 23, and the tightening force generated can compress the heat spreader plate 5 and the pre-made solder paste 30 for high-temperature pressure welding of the heat spreader plate 5.

[0027] This invention also provides a method for molding and preparing a composite material heat dissipation electronic module, comprising the following steps: Step 1: Clean the main mold with alcohol, let it air dry at room temperature, and then apply release agent to the surface at least twice, with an interval of at least 10 minutes between applications; Step 2: Place the metal heat dissipation and conductive insert 4 on the corresponding position on the top surface of the second-order rectangular body 15 of the main mold; Step 3: Lay three layers of inner skin carbon fiber layer 25 on the five surfaces of the main mold's second-order rectangular body 15: left, right, front, back, and top. The layering sequence is (±45° / 0° / 90°). Step 4: After laying the inner adhesive film layer, foam layer 26, and outer adhesive film layer on the left, right, front, and back surfaces of the main mold's second-order rectangular body 15, place the rectangular inlay 27 into the corresponding position of the foam layer. Step 5: Lay 6 layers of local carbon fiber 28 at the flange of the metal heat dissipation and conductive insert 4 and at the heat dissipation blocks 8 on the left and right sides, with the layering sequence being [±45° / (0°90°) / ±45°]s; Step 6: Lay three layers of outer skin carbon fiber layer 29 on the five surfaces of the main mold's second-order rectangular body 15: left, right, front, back, and top. The layering sequence is (90° / 0° / ±45°). Step 7: Make a vacuum bag, cure it in an autoclave, demold, mill the edges, and make holes to prepare a combination of carbon fiber structure 3 and metal heat dissipation and conductive insert 4; Step 8: Place the solder paste printing fixture 11 on the back of the metal heat dissipation and conductive insert 4, and position it with the metal heat dissipation and conductive insert 4 through the φ5 through hole; Step 9: Using the mesh-like hollow structure of the solder paste printing fixture 11, prepare lead-tin pre-made solder paste 30 in the groove on the back of the metal heat dissipation and conductive insert 4. After the solder paste is pre-made, remove the solder paste printing fixture 11. Step 10: Place the three heat spreaders 5 on the pre-made solder paste; Step 11: After the base plate 21 of the welding fixture 12 is connected to the support column 22 by screws, the combination of carbon fiber structure 3 and metal heat dissipation and conductive insert 4 is placed on the base plate 21 of the welding fixture 12. Then the top plate 23 of the welding fixture is connected to the support column 22 by screws. Finally, the set screw 24 passes through the top plate 23 to press the combination of carbon fiber structure 3 and metal heat dissipation and conductive insert 4 against the heat spreader 5. Step 12: Place the combination of carbon fiber structure 3 and metal heat dissipation and conductive insert 4, heat spreader 5 and welding fixture 12 into an oven, set the welding temperature, and perform lead-tin welding to obtain electronic module 2.

[0028] Example: See appendix Figure 1 As shown, the composite material electronic module 2 consists of a carbon fiber structure 3, a metal heat dissipation and conductive insert 4, and a heat spreader 5, among other components. The electronic module 2 has external dimensions of 180mm × 120mm × 80mm, a weight requirement of less than 0.5kg, and meets the 3W / cm² requirement. 2 Under the specified heat flux density, the module's operating temperature must not exceed 70℃ and the module's mounting surface lap resistance must not exceed 2.5mΩ. The carbon fiber structure 3 is a carbon fiber foam A-layer structure, and the heat spreader 5 is a rectangular structure with convective heat dissipation capability, made of aluminum alloy, and its surface is chemically nickel-plated.

[0029] See appendix Figure 2 As shown, the metal heat dissipation and conductive insert 4 consists of a heat dissipation tooth surface 6, a cold plate 7, heat dissipation blocks 8 on both sides, and a grounding boss 9. The metal heat dissipation and conductive insert 4 is integrally co-cured with the carbon fiber structure 3 through a pre-embedded form. The metal heat dissipation and conductive insert 4 is an integrally machined aluminum alloy structural component with electrical grounding and heat dissipation functions. The rectangular groove on it is chemically nickel-plated, and the remaining surfaces are treated with rainbow conductive oxidation.

[0030] See appendix Figure 3As shown, the main mold 10 is used for the thermoforming of the carbon fiber structure 3 and the metal heat dissipation and conductive insert 4. It consists of a working platform 13, a first-order rectangular body 14, and a second-order rectangular body 15. The working platform 13 is a cuboid structure with a thickness of 25mm. Its length and width are 300mm and 150mm larger than the length and width of the outer surface of the electronic module 2, respectively. The first-order rectangular body 14 has a thickness of 20mm, and its length and width are the same as the length and width of the outer surface of the electronic module 2, respectively. The geometry of the second-order rectangular body 15 is the same as the inner surface shape of the electronic module 2. The top surface of the second-order rectangular body 15 is provided with 10 φ5 circular blind holes for the precise positioning of the metal heat dissipation and conductive insert 4 on the main mold 10.

[0031] See appendix Figure 4 As shown, the solder paste printing fixture 11 consists of two parts: a boss 16 and a flat plate 17. The geometric dimensions of the boss 16 are consistent with the shape of the rectangular groove on the metal heat dissipation and conductive insert 4. The top surface of the boss 16 has a mesh-like perforated structure, and the wall thickness of the top surface is consistent with the thickness of the pre-made solder paste 30, which is t. The platform structure 17 has three rectangular grooves 18 in the middle. The length and width of the rectangular grooves 18 are 1mm smaller than the length and width of the boss 16, respectively. Their length is l and width is w. The bottom surface of the rectangular grooves 18 has a mesh-like perforated structure, composed of longitudinal and transverse ribs 19 and perforated portions 20. All longitudinal and transverse ribs 19 have the same width, t1, and all perforated portions 20 have the same width, t2. The top wall thickness of the boss 16, i.e., the thickness t of the pre-made solder paste 30, satisfies the following... In the formula: l is the length of the rectangular groove 18 (unit: mm); w is the width of the rectangular groove 18 (unit: mm); t1 is the width of the longitudinal and transverse ribs 19 of the rectangular groove 18 (unit: mm); t2 is the width of the hollow part 20 of the rectangular groove 18 (unit: mm); t3 is the actual thickness of the pre-made solder paste 30 after high-temperature welding (unit: mm).

[0032] See appendix Figure 5 As shown, the welding fixture 12 consists of a base plate 21, a support column 22, a top plate 23, and set screws 24. Both the base plate fixture 21 and the top plate fixture 23 are rectangular structures, each with a φ4.5 through hole. The support column fixture 22 has an M4 threaded hole at the center of each end for connecting the base plate fixture 21, the top plate fixture 23, and the support column 22. The top plate fixture 23 has three M5 threaded holes corresponding to the position of the heat spreader plate 5 for installing and tightening the set screws 24. The set screws 24 pass through the M5 threaded holes on the top plate fixture 23, and the resulting tightening force can compact the heat spreader plate 5 and the solder paste, enabling high-temperature pressure welding of the heat spreader plate 5.

[0033] See appendix Figure 6As shown, the preparation process used by the present invention to achieve its objective includes the following steps: (1) After cleaning the surface of the main mold 10, apply the release agent more than twice; (2) Place the metal heat dissipation and conductive insert 4 on the top surface of the second-order rectangular body 15 of the main mold at the corresponding position; (3) Three layers of inner skin carbon fiber layer 25 are laid on the five surfaces of the main mold second-order rectangular body 15: left, right, front, back and top. The laying sequence is (±45° / 0° / 90°). (4) After laying the inner adhesive film layer, foam layer 26 and outer adhesive film layer on the left, right, front and back four sides of the main mold second-order rectangular body 15, the rectangular insert 27 is placed in the corresponding position of the foam layer. (5) Six layers of local carbon fiber 28 are laid at the flange of the metal heat dissipation and conductive insert 4 and at the heat dissipation blocks 8 on the left and right sides, with the laying sequence being [±45° / (0°90°) / ±45°]s; (6) Three layers of outer skin carbon fiber layer 29 are laid on the five surfaces of the main mold second-order rectangular body 15: left, right, front, back and top. The laying sequence is (90° / 0° / ±45°). (7) A vacuum bag is made, which is then cured in an autoclave. After demolding, milling, and drilling, a combination of carbon fiber structure 3 and metal heat dissipation and conductive insert 4 is prepared. (8) Place the solder paste printing fixture 11 on the back of the metal heat dissipation conductive insert 4 and position it with the metal heat dissipation conductive insert 4 through the φ5 through hole; (9) Through the mesh-like hollow structure of the solder paste printing fixture 11, lead-tin pre-made solder paste 30 is prepared in the groove on the back of the metal heat dissipation and conductive insert 4. After the solder paste is pre-made, the solder paste printing fixture 11 is taken out. (10) Place the three heat spreaders 5 on the pre-made solder paste; (11) After the base plate 21 in the welding fixture 12 is connected to the support column 22 by screws, the combination of carbon fiber structure 3 and metal heat dissipation and conductive insert 4 is placed on the base plate fixture 21, and then the top plate fixture 23 is connected to the support column 22 by screws. Finally, the set screw 24 passes through the top plate fixture 23 to press the combination of carbon fiber structure 3 and metal heat dissipation and conductive insert 4 against the heat spreader 5. (12) The combination of carbon fiber structure 3 and metal heat dissipation and conductive insert 4, heat spreader 5 and welding fixture 12 are placed in an oven, the welding temperature is set, and lead-tin welding is performed to obtain electronic module 2.

[0034] The carbon fiber layer is T800 grade carbon fiber epoxy material, with a single layer thickness of 0.12 mm, and the foam material is PMI foam with a density of 110 g / cm³. 3 .

[0035] 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 person skilled in the art can easily conceive of various equivalent modifications or substitutions within the scope of the technology disclosed in the present invention, and such modifications or substitutions should all be covered within the scope of protection of the present invention.

Claims

1. A composite material heat dissipation electronic module molding die, wherein the electronic module (2) is composed of a carbon fiber structure (3), a metal heat dissipation and conductive insert (4), and a heat spreader (5), wherein the metal heat dissipation and conductive insert (4) is composed of a heat dissipation tooth surface (6), a cold plate (7), heat dissipation blocks (8) on the left and right sides, and a grounding boss (9); characterized in that, Includes main mold (10), solder paste printing fixture (11), and welding fixture (12); The main mold (10) is used for the thermoforming of the carbon fiber structure (3) and the metal heat dissipation and conductive insert (4). It consists of a working platform (13) and a forming surface located on the working platform (13). The working platform (13) is a cuboid structure with a size larger than that of the electronic module (2). The forming surface is a stepped rectangular structure, consisting of a first-order rectangular body (14) and a second-order rectangular body (15). The length and width of the first-order rectangular body (14) are consistent with the length and width of the outer surface of the electronic module (2), respectively. The geometry of the second-order rectangular body (15) is consistent with the shape of the inner surface of the electronic module (2). The solder paste printing fixture (11) is a rectangular structure with a boss, consisting of a boss (16) and a plate (17). The geometric dimensions of the boss (16) are consistent with the shape of the rectangular groove on the metal heat dissipation and conductive insert (4). The top surface of the boss (16) is a mesh-like hollow structure for solder paste printing pre-fabrication. The length and width of the plate (17) are 1mm smaller than the length and width of the inner surface of the electronic module (2). The plate (17) has 3 rectangular grooves (18) in the middle. The center of the rectangular grooves (18) is consistent with the center of the boss (16). The bottom surface of the rectangular grooves (18) is a mesh-like hollow structure. The welding fixture (12) consists of a base plate (21), a support column (22), a top plate (23), and a set screw (24). The base plate (21) is a hollow rectangular structure and is connected to the top plate (23) through the support column (22). The top plate (23) is a rectangular structure and has three M5 threaded holes at the position corresponding to the temperature distribution plate (5) for the installation and fastening of the set screw (24).

2. The composite material heat dissipation electronic module molding die according to claim 1, characterized in that, The top surface of the second-order rectangular body (15) is provided with a circular blind hole for the precise positioning of the metal heat dissipation and conductive insert (4) on the main mold (10).

3. The composite material heat dissipation electronic module molding die according to claim 1, characterized in that, The wall thickness of the top surface of the boss (16) is consistent with the thickness of the pre-made solder paste (30).

4. The composite material heat dissipation electronic module molding die according to claim 3, characterized in that, The thickness t of the top surface wall of the boss (16), i.e. the thickness of the pre-applied solder paste (30), satisfies the following: Where l: length of rectangular groove (18), unit: mm; w: Width of the rectangular groove (18), in mm; t1: Width of the longitudinal and transverse ribs (19) on the bottom surface of the rectangular groove (18), unit: mm; t2: Width of the hollow part (20) on the bottom surface of the rectangular groove (18), unit: mm; t3: Actual thickness of the pre-made solder paste (30) after high-temperature welding, unit: mm.

5. The composite material heat dissipation electronic module molding die according to claim 1, characterized in that, The plate (17) is designed with through holes around its perimeter for precise positioning of the solder paste printing fixture (11) on the electronic module (2) during solder paste printing.

6. The composite material heat dissipation electronic module molding die according to claim 1, characterized in that, The length and width of the rectangular groove (18) are 1 mm smaller than the length and width of the boss (16).

7. The composite material heat dissipation electronic module molding die according to claim 1, characterized in that, The bottom surface of the rectangular groove (18) is a mesh-like hollow structure, consisting of longitudinal and transverse ribs (19) and hollow parts (20), wherein all longitudinal and transverse ribs (19) have the same width and the hollow parts (20) have the same width.

8. The composite material heat dissipation electronic module molding die according to claim 1, characterized in that, The length and width dimensions are 20 mm larger than the length and width of the outer surface of the electronic module (2), and the thickness is 5 mm. The base plate (21) is designed with through holes around its perimeter for connecting the base plate (21) and the support column (22).

9. A composite material heat dissipation electronic module molding die according to claim 1, characterized in that, The support column (22) is a cylindrical structure with a diameter of φ8 and a height that is 5mm greater than the height of the electronic module (2). Each end of the support column (22) has an M4 threaded hole at its center for connecting the base plate (21), the top plate (23) and the support column (22).

10. A molding method for a composite material heat dissipation electronic module, characterized in that... The composite material heat dissipation electronic module molding die as described in claim 1 is used; the steps are as follows: Step 1: Clean the main mold (10) with alcohol, let it air dry at room temperature, and then apply release agent to the surface at least twice, with an interval of at least 10 minutes. Step 2: Place the metal heat dissipation and conductive insert (4) on the corresponding position on the top surface of the second-order rectangular body (15) of the main mold; Step 3: Lay three layers of inner skin carbon fiber layer (25) on the five surfaces of the main mold second-order rectangular body (15), namely the left, right, front, back and top surfaces, in the following order (±45° / 0° / 90°). Step 4: After laying the inner adhesive film layer, foam layer (26), and outer adhesive film layer on the left, right, front, and back four sides of the second-order rectangular body (15) of the main mold, place the rectangular inlay (27) into the corresponding position of the foam layer. Step 5: Lay 6 layers of local carbon fiber (28) at the flange of the metal heat dissipation and conductive insert (4) and at the heat dissipation blocks (8) on the left and right sides, with the layering sequence being [±45° / (0°90°) / ±45°]s; Step 6: Lay three layers of outer skin carbon fiber layer (29) on the five surfaces of the main mold second-order rectangular body (15), namely the left, right, front, back and top surfaces, in the following order (90° / 0° / ±45°). Step 7: Make a vacuum bag, cure it in an autoclave, demold, mill the edges, and make holes to prepare a combination of carbon fiber structure (3) and metal heat dissipation and conductive insert (4); Step 8: Place the solder paste printing fixture (11) on the back of the metal heat dissipation conductive insert (4) and position it with the metal heat dissipation conductive insert (4) through the φ5 through hole; Step 9: Using the mesh-like hollow structure of the solder paste printing fixture (11), lead-tin pre-made solder paste (30) is prepared in the groove on the back of the metal heat dissipation conductive insert (4). After the solder paste is pre-made, the solder paste printing fixture (11) is removed. Step 10: Place the three heat spreaders (5) on the pre-made solder paste; Step 11: After the base plate (21) of the welding fixture (12) is screwed to the support column (22), the combination of carbon fiber structure (3) and metal heat dissipation and conductive insert (4) is placed on the base plate (21) of the welding fixture (12). Then the top plate (23) of the welding fixture is screwed to the support column (22). Finally, the set screw (24) passes through the top plate (23) to press the combination of carbon fiber structure (3) and metal heat dissipation and conductive insert (4) against the heat spreader (5). Step 12: Place the combination of carbon fiber structure (3) and metal heat dissipation and conductive insert (4), heat spreader (5) and welding fixture (12) into the oven, set the welding temperature, and perform lead-tin welding to obtain electronic module (2).

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