High thermal conductivity aluminum-based silicon carbide-copper composite material and method of making same

Abstract

The application provides a high-thermal-conductivity aluminum-based silicon carbide-copper composite material and a preparation method thereof. The composite material is composed of a copper layer and an aluminum-based silicon carbide layer, and the preparation method adopts a complete process of hot rolling, diffusion annealing, cold rolling, softening annealing, finished product rolling and aging annealing, and the temperature, deformation, annealing speed and holding time of each process are accurately controlled, so that the technical problems of weak interface bonding, easy delamination and cracking, difficult consideration of thermal conductivity and mechanical properties, poor thermal expansion matching and low material yield of traditional composite plates are solved. The obtained composite material has the characteristics of high thermal conductivity, high strength, low expansion and uniform and stable structure, the process is simple and controllable, is suitable for large-scale production, and meets the application requirements of precise electronic heat dissipation devices.

Description

Technical Field

[0001] This invention belongs to the field of electronic packaging and heat dissipation materials technology, specifically relating to a high thermal conductivity aluminum-based silicon carbide-copper composite material and its preparation method. Background Technology

[0002] With the widespread application of 5G communication, artificial intelligence, high-performance computing, and high refresh rate display technologies in the 3C consumer electronics field, chip computing performance is growing exponentially, accompanied by a sharp increase in power consumption and heat flux density. At the same time, consumer electronics products continue to iterate towards thinner, lighter, more portable, and more integrated designs, resulting in extremely compressed internal space. Traditional passive heat dissipation solutions such as graphite films and metal heat sinks are no longer sufficient to meet the high-efficiency thermal management requirements of high-end devices.

[0003] Currently, most heat dissipation materials use single metal materials such as pure copper, stainless steel, and aluminum alloys. Pure copper has excellent thermal conductivity and outstanding heat dissipation performance, but its high cost and density hinder lightweight product design. Stainless steel has high strength and corrosion resistance at a lower cost, but its extremely poor thermal conductivity makes it unsuitable for high-efficiency heat dissipation and only suitable for special corrosion-resistant or high-structural-strength applications. Aluminum alloys have low density and significant lightweight advantages, good thermal conductivity, and excellent machinability; however, their strength is low at room temperature and rapidly decreases under high-temperature conditions. These single materials generally have performance limitations and cannot simultaneously achieve a synergistic balance of high thermal conductivity, lightweight, high strength, and low cost, making them unsuitable for the stringent structural-functional integration requirements of next-generation heat dissipation materials.

[0004] Copper-aluminum composites combine the high thermal conductivity of copper with the lightweight and low-cost advantages of aluminum, making them an important development direction for heat dissipation materials. However, existing copper-aluminum composites still have significant technical defects: on the one hand, the interfacial bonding strength between the copper and aluminum layers is insufficient, and the composite interface is prone to peeling and cracking, further reducing the bonding stability during high-temperature service and affecting product reliability; on the other hand, the aluminum alloy matrix has low high-temperature hardness and is prone to softening and deformation, resulting in poor overall structural support. In addition, both copper and aluminum have high coefficients of thermal expansion, resulting in poor thermal matching with core components such as chips and ceramic substrates. Long-term thermal cycling can easily lead to interfacial stress concentration, reducing the lifespan of devices. Therefore, developing a copper-aluminum based composite material that combines high interfacial bonding strength, high-temperature hardness, low coefficient of thermal expansion, and high thermal conductivity has become a core issue in overcoming the technical bottlenecks of existing heat dissipation materials and meeting the heat dissipation needs of high-end electronics. Summary of the Invention

[0005] This invention addresses the shortcomings of existing aluminum-based silicon carbide-copper composite materials, including low interfacial bonding strength, easy delamination and cracking, poor thermal expansion matching under thermal cycling, easy softening at high temperatures, difficulty in achieving a balance between thermal conductivity and mechanical properties, as well as the technical defects of traditional manufacturing processes such as poor forming stability, severe work hardening, coarse grain structure, low yield, poor dimensional accuracy, and difficulty in mass production of precision heat sinks and other electronic heat dissipation devices. It provides a high thermal conductivity aluminum-based silicon carbide-copper composite material by rationally limiting the thickness ratio of the copper layer to the aluminum-based silicon carbide layer, the particle size and volume fraction of silicon carbide particles, and the matrix alloy grade, thereby optimizing the thermal properties. The complete set of process parameters and procedures for composite rolling temperature and deformation, diffusion annealing, cold rolling, softening annealing, finished product rolling and aging annealing effectively solves the technical problems of easy formation of brittle phases at the composite interface, insufficient atomic diffusion, difficulty in releasing internal stress, insufficient plastic forming ability, uneven microstructure and properties, and mutual constraints between thermal conductivity and structural strength. At the same time, it improves the thermal expansion adaptability and high-temperature structural stability of materials, enhances product dimensional accuracy, surface quality and production yield, and meets the application requirements of high thermal conductivity, high strength, low deformation, long life and scalable preparation of high-end heat dissipation materials and precision electronic heat dissipation substrates.

[0006] The present invention also provides a method for preparing a high thermal conductivity aluminum-based silicon carbide-copper composite material.

[0007] The first aspect of the present invention provides a high thermal conductivity aluminum-based silicon carbide-copper composite material, comprising a copper layer and an aluminum-based silicon carbide layer disposed sequentially, wherein the thickness of the copper layer accounts for 10-60% of the total thickness of the composite material, and the thickness of the aluminum-based silicon carbide layer accounts for 40-90% of the total thickness of the composite material, wherein the aluminum-based silicon carbide layer comprises an aluminum alloy matrix and silicon carbide particles distributed in the aluminum alloy matrix.

[0008] This invention achieves high thermal conductivity aluminum-based silicon carbide by limiting the thickness ratio of the copper layer to the aluminum-based silicon carbide layer and by specifying that the aluminum-based silicon carbide layer is composed of an aluminum alloy matrix and dispersed silicon carbide particles. Copper composite materials have the following beneficial effects: A copper layer with a ratio of 10-60% can fully utilize the high thermal conductivity of pure copper and ensure the overall high thermal conductivity of the composite material; an aluminum-based silicon carbide layer with a ratio of 40-90% retains the lightweight and low-cost advantages of aluminum alloys, avoids the problem of high density and high cost caused by excessive use of pure copper, and achieves a synergistic balance between heat dissipation performance, economy, and lightweight.

[0009] The silicon carbide particles in the aluminum-based silicon carbide layer are uniformly distributed in the aluminum alloy matrix, which can effectively bear the load and hinder the movement of dislocations. This significantly improves the room temperature hardness, wear resistance and high temperature structural stability of the aluminum matrix, solves the defects of traditional aluminum alloys that are easy to soften at high temperatures and have insufficient strength, and enables the composite material to maintain good structural support under high temperature service conditions.

[0010] The introduction of silicon carbide particles significantly reduces the coefficient of thermal expansion of the aluminum-based silicon carbide layer, making the overall coefficient of thermal expansion of the composite material closer to that of devices such as chips and ceramic substrates. This improves thermal matching, reduces interfacial stress during thermal cycling, lowers the risk of failures such as delamination and cracking, and enhances the long-term reliability of the device.

[0011] The copper layer is responsible for efficient heat conduction and dissipation, while the aluminum-based silicon carbide layer provides structural support and high-temperature stability. The two are combined to form a structure-function integrated material that can simultaneously meet the stringent requirements of heat dissipation components for high thermal conductivity, high strength, low thermal expansion, and lightweight. It is suitable for high heat flux density heat dissipation scenarios such as 5G communication, high-performance computing, and consumer electronics.

[0012] According to some embodiments of the present invention, the copper layer includes one of TU1 copper layer, T1 copper layer or T2 copper layer.

[0013] TU1, T1, and T2 are all high-purity copper with excellent thermal conductivity, fully utilizing their high thermal conductivity to ensure the composite material possesses excellent overall thermal conductivity, meeting the requirements for efficient heat dissipation. TU1 is oxygen-free copper with extremely low oxygen content, eliminating the risk of hydrogen embrittlement. T1 and T2 have high purity and few impurities, making them less prone to generating oxide impurities during hot rolling and annealing processes. They can form a stable and dense metallurgical interface with the aluminum-based silicon carbide layer, improving interface bonding strength and preventing delamination and cracking. All three types of pure copper exhibit good plasticity and ductility, demonstrating good deformation coordination with the aluminum-based silicon carbide layer during hot rolling, cold rolling, and annealing processes, minimizing edge cracking and strip breakage, and significantly improving the material processing yield. TU1 is suitable for high-reliability, high-end applications, T1 balances performance and cost, and T2 offers high cost-effectiveness and is easy to mass-produce. The appropriate choice can be made flexibly according to different application requirements to achieve the optimal match between performance and cost.

[0014] According to some embodiments of the present invention, the grade of the aluminum alloy matrix includes one of 2009 aluminum alloy, 2024 aluminum alloy, 2080 aluminum alloy, 6061 aluminum alloy, 6063 aluminum alloy, 6090 aluminum alloy, 6091 aluminum alloy, 6092 aluminum alloy, 7075 aluminum alloy, 706 aluminum alloy or 7090 aluminum alloy.

[0015] Using aluminum alloys of grades 2009, 2024, 2080, 6061, 6063, 6090, 6091, 6092, 7075, 7068, and 7090 as the matrix for aluminum-based silicon carbide provides the composite material with stable and excellent matrix strength, processing plasticity, and age-hardening ability. Different grades can respectively meet the requirements of medium-high strength, high plasticity, and ultra-high strength. When matched with silicon carbide particle reinforcement, it can significantly improve the overall hardness, high-temperature stability, and structural support of the aluminum layer. At the same time, it ensures that the aluminum matrix has good plastic deformation ability in preparation processes such as hot rolling, cold rolling, and annealing, avoiding processing cracks. This allows the composite material to take into account mechanical properties, thermal conductivity, and processability, meeting the stringent requirements of electronic heat dissipation devices.

[0016] According to some embodiments of the present invention, the particle size D50 of the silicon carbide particles is 5~15μm.

[0017] The particle size D50 of silicon carbide particles is controlled within 5~15μm. This ensures that the particles are uniformly dispersed in the aluminum alloy matrix and do not easily agglomerate, resulting in a uniform structure and stable performance of the aluminum-based silicon carbide layer. It also fully utilizes the load-bearing and strengthening effects of the particles, effectively improving the strength, hardness, and high-temperature stability of the composite material. At the same time, this particle size range will not cause a sharp decrease in the plasticity of the aluminum matrix due to excessively large particles, avoiding problems such as cracking and band breakage during plastic deformation processes such as hot rolling and cold rolling. It balances the strengthening effect and processability, and can also reasonably control the coefficient of thermal expansion of the material, improving the thermal matching with chips and ceramic substrates.

[0018] According to some embodiments of the present invention, the particle size D50 of the silicon carbide particles is any value among 5μm, 6μm, 7μm, 8μm, 9μm, 10μm, 11μm, 12μm, 13μm, 14μm, and 15μm, such as 10μm, or any range formed by both, such as 8μm to 12μm.

[0019] According to some embodiments of the present invention, the volume fraction of the silicon carbide particles in the aluminum alloy matrix is ​​5-30%.

[0020] By controlling the volume fraction of silicon carbide particles in the aluminum alloy matrix to 5-30%, the high-temperature strengthening, modulus enhancement, and thermal expansion coefficient regulation effects of silicon carbide can be fully utilized while ensuring uniform particle dispersion and no agglomeration. This effectively improves the strength, hardness, wear resistance, and high-temperature softening resistance of the aluminum-based silicon carbide layer. At the same time, it avoids problems such as insufficient reinforcement due to too low particle content, or cracking, strip breakage, and reduced yield during hot rolling and cold rolling due to excessive particle content, which significantly damages the plasticity of the matrix. This allows the composite material to have excellent mechanical properties, thermal conductivity, and processability, making it stable and suitable for the mass production and long-term reliable use of electronic heat dissipation devices.

[0021] According to some embodiments of the present invention, the volume fraction of the silicon carbide particles in the aluminum alloy matrix is ​​any value among 5%, 6%, 7%, 8%, 9%, 10%, 15%, 20%, 25%, and 30%, such as 15%, or any range formed by both, such as 10% to 20%.

[0022] According to some embodiments of the present invention, the high thermal conductivity aluminum-based silicon carbide-copper composite material has a thermal conductivity exceeding 260 W / (m²). K).

[0023] A second aspect of the present invention provides a method for preparing a high thermal conductivity aluminum-based silicon carbide-copper composite material according to the first aspect of the present invention, comprising the following steps: (1) The copper layer material and the aluminum-based silicon carbide layer material are stacked and then hot-rolled to obtain a strip billet; (2) After diffusion annealing, the strip is then subjected to cold rolling and softening annealing in sequence; (3) After rolling the strip from step (2) into finished product, age annealing is performed to obtain the high thermal conductivity aluminum-based silicon carbide-copper composite material.

[0024] The stepwise preparation method described above, involving hot rolling composite, diffusion annealing, cold rolling, softening annealing, finished product rolling, and aging annealing, enables a strong metallurgical bond between the copper layer and the aluminum-based silicon carbide layer, effectively improving interfacial bonding strength and preventing delamination cracking. Diffusion annealing fully releases the internal stress generated during the composite process, promotes interfacial atomic diffusion, and inhibits the formation of thick, brittle intermetallic compounds, ensuring interfacial structural stability. Cold rolling and finished product rolling achieve precise material thinning and forming, while softening annealing eliminates work hardening, balancing dimensional accuracy and processing plasticity. Finally, aging annealing precipitates nano-dispersed reinforcing phases within the aluminum alloy matrix, further enhancing the composite material's strength, hardness, and thermal conductivity. The resulting material possesses high thermal conductivity, high interfacial strength, high-temperature stability, and good formability. The overall process is controllable, with a high yield, making it suitable for large-scale production of high thermal conductivity aluminum-based silicon carbide. Copper composite materials.

[0025] According to some embodiments of the present invention, in step (1), the temperature of the hot rolling composite is 300°C. 550℃.

[0026] Controlling the hot-rolled composite temperature between 300 and 550°C provides sufficient thermal diffusion energy for the interface atoms of the copper layer and the aluminum-based silicon carbide layer, achieving a high-strength metallurgical bond. It also avoids the formation of continuous brittle intermetallic compounds such as CuAl2 and Cu9Al4 at the interface due to excessively high temperatures, preventing interface embrittlement and a decrease in peel strength. At the same time, this temperature range ensures that the material has good plastic deformation capacity, allowing the composite to be completed smoothly under the set deformation amount without defects such as cracking or band breakage, thus balancing the interface bonding quality, material mechanical properties, and process forming stability.

[0027] According to some embodiments of the present invention, in step (1), the temperature of hot rolling composite is any value among 300℃, 350℃, 400℃, 450℃, 500℃, and 550℃, such as 400℃, or any range formed by both, such as 350℃~450℃.

[0028] According to some embodiments of the present invention, in step (1), the deformation amount of the hot-rolled composite is 30. 60%.

[0029] The hot-rolled composite deformation is controlled at 30-60%. This deformation ensures that the composite interface is uniform, free of voids and unbonded areas. It also prevents uneven deformation, edge cracking or breakage of the aluminum-based silicon carbide layer due to excessive deformation, while avoiding insufficient bonding and weak bonding strength due to insufficient deformation. This balances the quality of interface bonding, forming stability and yield, giving the composite material excellent interface reliability and processing adaptability.

[0030] According to some embodiments of the present invention, in step (1), the deformation of the hot-rolled composite is any value of 30%, 35%, 40%, 45%, 50%, 55%, 60%, such as 40%, or a range of any two, such as 35%~50%.

[0031] According to some embodiments of the present invention, the hot rolling composite is carried out under a protective atmosphere of ammonia decomposition gas.

[0032] According to some embodiments of the present invention, in step (2), the diffusion annealing is to heat the strip at 450°C. Continuous annealing was carried out at 550℃ under a protective atmosphere of ammonia decomposition gas, with an annealing rate of 1. 8 m / min.

[0033] Setting diffusion annealing at 450~550℃, with ammonia decomposition gas protection and a continuous annealing speed of 1~8m / min, can effectively prevent oxidation of the copper layer and aluminum-based silicon carbide layer under a protective atmosphere, providing sufficient diffusion motive force for interface atoms, further strengthening the metallurgical bond between copper and aluminum-based silicon carbide, and precisely controlling the growth of intermetallic compounds to maintain a thin and dense non-brittle interface layer; continuous annealing combined with an appropriate speed can uniformly release the internal stress generated by hot rolling composite, preventing warping, cracking and delamination in subsequent processing, improving the dimensional uniformity and interface stability of the material, and ensuring that the composite material has higher forming quality and yield in subsequent cold rolling and finished product rolling.

[0034] According to some embodiments of the present invention, in step (2), the diffusion annealing is to continuously anneal the strip at any temperature value among 450°C, 460°C, 470°C, 480°C, 490°C, 500°C, 510°C, 520°C, 530°C, 540°C, and 550°C, such as 500°C, or any range formed by both, such as 480°C to 520°C, under an ammonia decomposition gas protective atmosphere; the annealing speed is any value among 1 m / min, 2 m / min, 3 m / min, 4 m / min, 5 m / min, 6 m / min, 7 m / min, and 8 m / min, such as 4 m / min, or any range formed by both, such as 3 m / min to 5 m / min.

[0035] According to some embodiments of the present invention, in step (2), during the cold rolling process, the total deformation of each rolling pass is 30. 60%, with a deformation amount of 8 per pass. 20%.

[0036] By controlling the total deformation of each rolling pass in the cold rolling process to 30-60% and the deformation of each pass to 8-20%, the material can be adapted to the relatively low plasticity of aluminum-based silicon carbide composites. This achieves efficient material thinning while avoiding localized uneven deformation, edge cracks, or even fractures caused by excessive deformation in a single pass, effectively improving forming stability and yield. This deformation range ensures that the material structure is dense and the thickness is uniform, without affecting subsequent processes due to excessive work hardening. This allows the composite material to maintain good plasticity and dimensional accuracy during continuous processing, balancing thinning efficiency, processing performance, and product qualification rate.

[0037] According to some embodiments of the present invention, in step (2), during the cold rolling process, the total deformation of each rolling pass is any value of 30%, 35%, 40%, 45%, 50%, 55%, 60%, such as 45%, or any range of two, such as 40%~50%; the deformation of each pass is any value of 8%, 10%, 12%, 14%, 16%, 18%, 20%, such as 14%, or any range of two, such as 12%~16%.

[0038] According to some embodiments of the present invention, in step (2), the softening annealing is performed at 300°C. Continuous annealing was carried out at 500℃ under a protective atmosphere of ammonia decomposition gas, with an annealing rate of 4. 10 m / min.

[0039] Continuous softening annealing at 300~500℃ in an ammonia decomposition gas protective atmosphere at a speed of 4~10m / min can effectively eliminate work hardening and internal stress caused by cold rolling, restore the plasticity of the aluminum-based silicon carbide layer and copper layer, and avoid cracking and strip breakage in subsequent processing. At the same time, the ammonia decomposition gas protection can prevent material surface oxidation and ensure interface cleanliness and stability. The appropriate annealing temperature and speed can fully soften the matrix while avoiding excessive grain growth, so that the material maintains good mechanical properties and formability, and provides a stable and reliable billet state for subsequent finished product rolling.

[0040] According to some embodiments of the present invention, in step (2), the softening annealing is performed continuously at any temperature value among 300℃, 320℃, 350℃, 380℃, 400℃, 420℃, 450℃, 480℃, and 500℃, such as 400℃, or any range formed by both, such as 350℃~450℃, under the protective atmosphere of ammonia decomposition gas; the annealing speed is any value among 4m / min, 5m / min, 6m / min, 7m / min, 8m / min, 9m / min, and 10m / min, such as 6m / min, or any range formed by both, such as 5m / min~8m / min.

[0041] According to some embodiments of the present invention, in step (3), the total deformation of the finished product rolling is 20. 40%, with a deformation amount of 8 per pass. 20%.

[0042] The total deformation of the finished product during rolling is controlled at 20-40%, and the deformation per pass is controlled at 8-20%, which ensures the quality of aluminum-based silicon carbide. Under the premise of safe plastic molding of copper composite materials, precise rolling to the target finished thickness can improve the material density and dimensional accuracy. It can also avoid edge cracks, fractures or interface delamination of the aluminum-based silicon carbide layer due to excessive deformation, while ensuring that the required thickness and microstructure uniformity are not failed due to insufficient deformation. It takes into account the dimensional accuracy, interface stability, surface quality and yield of the final product, so that the composite material meets the ultra-thin and high-precision requirements of precision electronic heat dissipation devices.

[0043] According to some embodiments of the present invention, in step (3), the total deformation of the finished product rolling is any value of 20%, 25%, 30%, 35%, 40%, such as 30%, or any range of two, such as 25% to 35%; the deformation per pass is any value of 8%, 10%, 12%, 14%, 16%, 18%, 20%, such as 14%, or any range of two, such as 10% to 16%.

[0044] According to some embodiments of the present invention, in step (3), the aging annealing is carried out in a bell-type furnace under a protective atmosphere of ammonia decomposition gas, and the annealing temperature is 120°C. 200℃, heat preservation 1 Cooled in the furnace after 10 hours.

[0045] In a bell-type furnace under an ammonia decomposition gas protective atmosphere, aging annealing is performed at 120~200℃ for 1~10h followed by furnace cooling. This process allows for the in-situ precipitation of fine and dispersed nano-reinforcing phases within the aluminum alloy matrix, significantly improving the room temperature and high temperature strength and hardness of the aluminum-based silicon carbide layer. Simultaneously, it optimizes the material's thermal conductivity pathway and enhances the overall thermal conductivity. The ammonia decomposition gas protection effectively prevents oxidation and interface degradation during annealing, while furnace cooling further eliminates internal stress and stabilizes the microstructure and properties. This temperature and time range fully leverages the aging strengthening effect without causing coarsening of the reinforcing phase or performance degradation. Ultimately, the composite material achieves comprehensive performance characteristics of high strength, high thermal conductivity, high temperature stability, and reliable interfaces, meeting the long-term service requirements of high-end electronic heat dissipation devices.

[0046] According to some embodiments of the present invention, in step (3), the aging annealing is carried out in a bell-type furnace under the protective atmosphere of ammonia decomposition gas; the annealing temperature is any value among 120℃, 130℃, 140℃, 150℃, 160℃, 170℃, 180℃, 190℃, and 200℃, such as 150℃, or any range formed by both, such as 140℃~170℃; the holding time is any value among 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, and 10h, such as 5h, or any range formed by both, such as 3h~6h, followed by furnace cooling.

[0047] According to some embodiments of the present invention, the preparation method of high thermal conductivity aluminum-based silicon carbide-copper composite material can be further subdivided into the following steps: Raw material cleaning: During cleaning, three sets of steel wire brushes are used to remove oil and oxide layers from the surface of the raw materials, combined with hot water spray (60-80℃), and then hot air is blown dry.

[0048] Hot-rolled composite: heating temperature (300-550℃), composite deformation during rolling 30-60%. Composite is carried out under an ammonia decomposition atmosphere. Diffusion annealing: The composite strip is subjected to diffusion annealing via continuous annealing. The annealing temperature is 450-550℃, and the annealing speed is 1-8 m / min. Ammonia decomposition gas is introduced for protection during the annealing process.

[0049] Cold rolling thinning: The total deformation in each cold rolling pass is 30-60%, and the deformation per pass is 8-20%.

[0050] Softening annealing: To eliminate work hardening after cold rolling, softening annealing is performed through continuous annealing. Annealing temperature is 300-500℃, and annealing speed is 4-10 m / min. Ammonia decomposition gas is introduced for protection during the annealing process.

[0051] Finished product rolling: Roll to the required thickness of the finished product. The total deformation of the finished product rolling is 20-40%, and the deformation per pass is 8-20%.

[0052] Aging annealing: Aging annealing is carried out in a bell-type furnace at a temperature of 120-200℃ for 1-10 hours. Ammonia decomposition gas is introduced for protection during the annealing process. The furnace is cooled after annealing. Detailed Implementation

[0053] The following will describe the concept and technical effects of the present invention clearly and completely with reference to embodiments, so as to fully understand the purpose, features and effects of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are all within the scope of protection of the present invention.

[0054] In the description of this invention, the terms "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the illustrative expressions 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 one or more embodiments or examples.

[0055] Unless otherwise specified, "room temperature" in this invention means 25℃±5℃.

[0056] Unless otherwise specified, "about" in this invention means that the allowable error is within ±2%.

[0057] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0058] Example 1 A high thermal conductivity aluminum-based silicon carbide-copper composite material was prepared with a thickness of 0.3 mm.

[0059] Of these, TU1 copper accounts for 40% of the finished product thickness. The aluminum-based silicon carbide material accounts for 60% of the finished product thickness. In the aluminum-based silicon carbide, the aluminum matrix is ​​6061 aluminum alloy, the volume percentage of silicon carbide particles is 30%, and the size D50 of the silicon carbide particles is 10μm.

[0060] The specific preparation method is as follows: (1) Raw material cleaning: During cleaning, three sets of steel wire brushes are used to remove oil stains and oxide layers from the surface of the raw materials, combined with hot water spraying at 70°C, and then hot air drying. (2) Hot rolling composite: heating temperature 400℃, rolling composite deformation 40%, hot rolling composite is carried out in a protective atmosphere of ammonia decomposition gas; (3) Diffusion annealing: The composite strip blank is subjected to diffusion annealing by continuous annealing. The annealing temperature is 500℃ and the annealing speed is 2m / min. Ammonia decomposition gas is introduced for protection during the annealing process; (4) Cold rolling thinning: The total deformation in each cold rolling pass is 40%, and the deformation per pass is 10%; (5) Softening annealing: To eliminate work hardening after cold rolling, softening annealing is performed by continuous annealing. The annealing temperature is 450℃, and the annealing speed is 4m / min. Ammonia decomposition gas is introduced for protection during the annealing process; (6) Finished product rolling: Roll to the required thickness of the finished product, with a total deformation of 30% and a deformation of 10% per pass; (7) Aging annealing: Aging annealing is carried out in a bell-type furnace at a temperature of 160℃ for 4 hours. Ammonia decomposition gas is introduced for protection during the annealing process. The furnace is cooled after annealing.

[0061] The performance characteristics of the finished product are shown in the table.

[0062] Example 2 A high thermal conductivity aluminum-based silicon carbide-copper composite material was prepared with a thickness of 0.3 mm.

[0063] Of these, TU1 copper accounts for 50% of the finished product thickness. The aluminum-based silicon carbide material accounts for 50% of the finished product thickness. In the aluminum-based silicon carbide, the aluminum matrix is ​​6061 aluminum alloy, the volume percentage of silicon carbide particles is 30%, and the size D50 of the silicon carbide particles is 10μm.

[0064] The specific preparation method is the same as in Example 1.

[0065] Example 3 A high thermal conductivity aluminum-based silicon carbide-copper composite material was prepared with a thickness of 0.2 mm.

[0066] Of these, TU1 copper accounts for 40% of the finished product thickness. Aluminum-based silicon carbide material accounts for 60% of the finished product thickness. In aluminum-based silicon carbide, the aluminum matrix is ​​2024 aluminum alloy, the volume percentage of silicon carbide particles is 20%, and the size D50 of the silicon carbide particles is 10μm.

[0067] The specific preparation method is as follows: (1) Raw material cleaning: During cleaning, three sets of steel wire brushes are used to remove oil stains and oxide layers from the surface of the raw materials, combined with hot water spraying at 70°C, and then hot air drying. (2) Hot rolling composite: heating temperature 400℃, rolling composite deformation 40%, hot rolling composite is carried out in a protective atmosphere of ammonia decomposition gas; (3) Diffusion annealing: The composite strip blank is subjected to diffusion annealing by continuous annealing. The annealing temperature is 500℃ and the annealing speed is 2m / min. Ammonia decomposition gas is introduced for protection during the annealing process; (4) Cold rolling thinning: The total deformation in each cold rolling pass is 40%, and the deformation per pass is 10%; (5) Softening annealing: To eliminate work hardening after cold rolling, softening annealing is performed by continuous annealing. The annealing temperature is 490℃, and the annealing speed is 4m / min. Ammonia decomposition gas is introduced for protection during the annealing process; (6) Finished product rolling: Roll to the required thickness of the finished product, with a total deformation of 30% and a deformation of 10% per pass; (7) Aging annealing: Aging annealing is carried out in a bell-type furnace at a temperature of 190℃ for 6 hours. Ammonia decomposition gas is introduced for protection during the annealing process. The furnace is cooled after annealing.

[0068] The other steps are the same as in Example 1.

[0069] Example 4 A high thermal conductivity aluminum-based silicon carbide-copper composite material was prepared with a thickness of 0.2 mm.

[0070] Of these, TU1 copper accounts for 25% of the finished product thickness. The aluminum-based silicon carbide material accounts for 75% of the finished product thickness. In the aluminum-based silicon carbide, the aluminum matrix is ​​2024 aluminum alloy, the volume percentage of silicon carbide particles is 20%, and the size D50 of the silicon carbide particles is 10μm.

[0071] The specific preparation method is as follows: (1) Raw material cleaning: During cleaning, three sets of steel wire brushes are used to remove oil stains and oxide layers from the surface of the raw materials, combined with hot water spraying at 70°C, and then hot air drying. (2) Hot rolling composite: heating temperature 400℃, rolling composite deformation 40%, hot rolling composite is carried out in a protective atmosphere of ammonia decomposition gas; (3) Diffusion annealing: The composite strip blank is subjected to diffusion annealing by continuous annealing. The annealing temperature is 500℃ and the annealing speed is 2m / min. Ammonia decomposition gas is introduced for protection during the annealing process; (4) Cold rolling thinning: The total deformation in each cold rolling pass is 40%, and the deformation per pass is 10%; (5) Softening annealing: To eliminate work hardening after cold rolling, softening annealing is performed by continuous annealing. The annealing temperature is 490℃, and the annealing speed is 4m / min. Ammonia decomposition gas is introduced for protection during the annealing process; (6) Finished product rolling: Roll to the required thickness of the finished product, with a total deformation of 30% and a deformation of 10% per pass; (7) Aging annealing: Aging annealing is carried out in a bell-type furnace at a temperature of 190℃ for 6 hours. Ammonia decomposition gas is introduced for protection during the annealing process. The furnace is cooled after annealing.

[0072] Comparative Example 1 A copper-aluminum composite material was prepared with a finished product thickness of 0.3 mm.

[0073] In this case, the thickness of TU1 copper accounts for 40 wt% of the finished product thickness, and the thickness of the aluminum-based material accounts for 60% of the finished product thickness. The aluminum matrix is ​​6061 aluminum alloy, which does not contain silicon carbide particles, and the preparation method is the same as in Example 1.

[0074] Comparative Example 2 A copper-aluminum composite material was prepared. The difference between this material and Example 1 is that the heating temperature for hot rolling composite in step (2) is 150°C, while the rest is the same as in Example 1.

[0075] Performance testing The yield strength, tensile strength, elongation, elastic modulus, thermal conductivity, and interfacial peel strength of the composite materials in the examples and comparative examples were tested.

[0076] Yield strength, tensile strength and elongation, and modulus of elasticity: tested in accordance with GB / T 228.1-2021 "Metallic materials - Tensile testing - Part 1: Test method at room temperature".

[0077] Thermal conductivity: Refer to GB / T 22588 The test was conducted according to the 2008 standard "Measuring Thermal Diffusion Coefficient or Thermal Conductivity by Flash Method".

[0078] Interface peel strength test method: The composite strip is cut into strips along the rolling direction with a width of 20 mm and a length of 200 mm. The copper layer and aluminum-based silicon carbide layer are pre-peeled. The peeled copper layer and aluminum-based silicon carbide layer are bent so that the copper layer, aluminum-based silicon carbide layer and unpeeled composite strip form a T shape. The peeled copper layer and aluminum-based silicon carbide layer are put into the clamp of the tensile machine. The tensile speed is 20 mm / min. The tensile force is recorded and divided by the sample width to obtain the peel strength.

[0079] The results are shown in Table 1.

[0080] Table 1

[0081] As can be clearly seen from the data in Table 1, with the adjustment of the silicon carbide particle volume fraction and preparation process parameters, the samples of each embodiment exhibit obvious regular changes in performance indicators such as interfacial bonding strength, strength, and thermal conductivity. The comparative examples, due to not using the raw material parameters and composite process specified in this invention, suffer from poor interfacial bonding, low thermal conductivity, and insufficient mechanical strength. Specifically: The optimal parameter range for silicon carbide particle size D50 (5-15 μm) and volume fraction (5-30%) defined in this invention enables the composite material to form a uniform and dense microstructure, taking into account both high thermal conductivity and low thermal expansion characteristics, while significantly improving interfacial bonding strength and structural stability.

[0082] The complete process flow of this invention, including hot rolling composite, diffusion annealing, cold rolling, softening annealing, finished product rolling, and aging annealing, along with the corresponding temperature, deformation, annealing speed, and holding time parameters, can effectively eliminate composite internal stress, inhibit the formation of brittle intermetallic compounds, and prevent plate delamination, warping, and cracking.

[0083] The process and raw material parameters of this invention work synergistically to significantly improve the thermal conductivity, mechanical strength, dimensional stability and production yield of aluminum-based silicon carbide-copper composite materials. The overall performance is significantly better than existing conventional formulations and preparation processes, and can meet the practical application requirements of precision electronic heat dissipation devices.

[0084] The present invention has been described in detail above with reference to the embodiments. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A high thermal conductivity aluminum-based silicon carbide-copper composite material, characterized in that, The composite material includes a copper layer and an aluminum-based silicon carbide layer arranged sequentially. The thickness of the copper layer accounts for 10-60% of the total thickness of the composite material, and the thickness of the aluminum-based silicon carbide layer accounts for 40-90% of the total thickness of the composite material. The aluminum-based silicon carbide layer includes an aluminum alloy matrix and silicon carbide particles distributed in the aluminum alloy matrix.

2. The high thermal conductivity aluminum-based silicon carbide-copper composite material according to claim 1, characterized in that, The copper layer includes one of TU1 copper layer, T1 copper layer or T2 copper layer.

3. The high thermal conductivity aluminum-based silicon carbide-copper composite material according to claim 1, characterized in that, The grade of the aluminum alloy matrix includes one of 2009 aluminum alloy, 2024 aluminum alloy, 2080 aluminum alloy, 6061 aluminum alloy, 6063 aluminum alloy, 6090 aluminum alloy, 6091 aluminum alloy, 6092 aluminum alloy, 7075 aluminum alloy, 7068 aluminum alloy or 7090 aluminum alloy.

4. The high thermal conductivity aluminum-based silicon carbide-copper composite material according to claim 1, characterized in that, The particle size D50 of the silicon carbide particles is 5~15μm.

5. The high thermal conductivity aluminum-based silicon carbide-copper composite material according to claim 1, characterized in that, The volume fraction of the silicon carbide particles in the aluminum alloy matrix is ​​5-30%.

6. A method for preparing a high thermal conductivity aluminum-based silicon carbide-copper composite material as described in any one of claims 1 to 5, characterized in that, Includes the following steps: (1) The copper layer material and the aluminum-based silicon carbide layer material are stacked and then hot-rolled to obtain a strip billet; (2) After diffusion annealing, the strip is then subjected to cold rolling and softening annealing in sequence; (3) After rolling the strip from step (2) into finished product, age annealing is performed to obtain the high thermal conductivity aluminum-based silicon carbide-copper composite material.

7. The method according to claim 6, characterized in that, In step (1), the hot rolling temperature is 300°C. 550℃; and / or, the deformation of the hot-rolled composite is 30. 60%; and / or, the hot rolling composite is carried out under a protective atmosphere of ammonia decomposition gas.

8. The method according to claim 6, characterized in that, In step (2), the diffusion annealing is to heat the strip at 450°C. Continuous annealing was carried out at 550℃ under a protective atmosphere of ammonia decomposition gas, with an annealing rate of 1. 8 m / min; and / or, during the cold rolling process, the total deformation per pass is 30. 60%, with a deformation amount of 8 per pass. 20%; and / or, the softening annealing is performed at 300°C. Continuous annealing was carried out at 500℃ under a protective atmosphere of ammonia decomposition gas, with an annealing rate of 4. 10 m / min.

9. The method according to claim 6, characterized in that, In step (3), the total deformation of the finished product during rolling is 20. 40%, with a deformation amount of 8 per pass. 20%.

10. The method according to claim 6, characterized in that, In step (3), the aging annealing is carried out in a bell-type furnace under a protective atmosphere of ammonia decomposition gas, and the annealing temperature is 120°C. 200℃, heat preservation 1 Cooled in the furnace after 10 hours.

Images