High-thermal-conductivity and high-compactness aluminum alloy material as well as preparation method and application thereof

Abstract

The invention discloses an aluminum alloy material with high thermal conductivity and high compactness as well as a preparation method and application thereof, and the aluminum alloy material with high thermal conductivity and high compactness comprises the following chemical components in percentage by mass: 0.3-0.6% of Si, 0.5-0.8% of Mg, less than or equal to 0.08% of Fe, less than or equal to 0.08% of Cu, less than or equal to 0.005% of Mn, 0.001-0.02% of Cr, less than or equal to 0.008% of Zn, less than or equal to 0.008% of Ti, 0.001-0.03% of La and the balance of Al and inevitable impurities. According to the method, the component purity is guaranteed through smelting casting and homogenization treatment, grain refinement and tissue densification are achieved by combining large-deformation cold forging forming, and then a strengthening phase is fine and evenly separated out through solid solution and two-stage aging cooperation; and finally, the high-heat-conductivity and high-compactness aluminum alloy material with the tensile strength larger than or equal to 200 MPa, the heat conductivity coefficient larger than or equal to 200 W / (m.K) and the excellent surface compactness is prepared.

Description

Technical Field

[0001] This invention relates to the field of metal materials technology, and in particular to a high thermal conductivity and high density aluminum alloy material, its preparation method and its application. Background Technology

[0002] With the rapid development of 5G communication, data centers and high-end electronic equipment, the power density of core optical modules and other devices is constantly increasing, which puts forward higher requirements for the precision structural components that support these devices: they must not only have sufficient mechanical strength and dimensional accuracy, but also have excellent thermal management capabilities to efficiently dissipate the heat generated by the main body, so as to ensure the long-term reliable operation of the equipment.

[0003] Currently, the thermal conductivity of commonly used structural aluminum alloys (such as 6063 aluminum alloy and zinc alloy) is generally below 180 W / (m·K), making it difficult to meet the high thermal conductivity requirements of over 200 W / (m·K). While pure aluminum has a high thermal conductivity, its strength is low, and its processing performance is insufficient to meet the forming requirements of complex and precise structures. Adding alloying elements to improve strength typically introduces more solid-solution atoms and a second phase, resulting in significant scattering of electrons and phonons, leading to a marked decrease in thermal conductivity. Furthermore, aluminum alloy parts prepared by traditional die casting or extrusion molding processes are prone to internal defects such as shrinkage cavities and inclusions, and have insufficient surface density. During subsequent high-requirement electroplating processes, problems such as pinholes and blistering are likely to occur, affecting the product's appearance quality, corrosion resistance, and long-term reliability.

[0004] Therefore, developing an aluminum alloy material and its forming process that combines high strength (tensile strength ≥200 MPa), high thermal conductivity (≥200 W / (m·K)), excellent cold forging formability and good electroplating adaptability has become an urgent technical problem to be solved in this field. Summary of the Invention

[0005] The purpose of this application is to provide a high thermal conductivity and high density aluminum alloy material, its preparation method, and its application. In this scheme, the content of harmful impurity elements such as Fe, Cu, Mn, and Zn is strictly limited to reduce the scattering of hot carriers by coarse intermetallic compounds and solid solution atoms. A trace amount of La is creatively added to form a stable compound with residual Fe and Si, purifying grain boundaries, optimizing the microstructure, and systematically reducing scattering centers. Simultaneously, this application ensures compositional purity through melting, casting, and homogenization treatment, combined with large-deformation cold forging to achieve grain refinement and microstructure densification. Then, solid solution treatment and two-stage aging synergistically induce the fine and uniform precipitation of strengthening phases, ultimately yielding a high thermal conductivity and high density aluminum alloy material with a tensile strength ≥200 MPa, a thermal conductivity ≥200 W / (m·K), and excellent surface density.

[0006] To address the aforementioned technical problems, this application provides a high thermal conductivity and high density aluminum alloy material. The chemical composition of this high thermal conductivity and high density aluminum alloy material, by mass percentage, specifically includes: Si: 0.3-0.6%, Mg: 0.5-0.8%, Fe: ≤ 0.08%, Cu: ≤ 0.08%, Mn: ≤ 0.005%, Cr: 0.001~0.02%, Zn: ≤ 0.008%, Ti: ≤ 0.008%, La: 0.001~0.03%, The balance consists of Al and unavoidable impurities.

[0007] Preferably, the Fe content is ≤0.05%, and the individual content of the unavoidable impurities is ≤0.008%, and the total content is ≤0.01%.

[0008] To address the aforementioned technical problems, this application provides a method for preparing a high thermal conductivity and high density aluminum alloy material, used to prepare such a material. The method for preparing the high thermal conductivity and high density aluminum alloy material includes: Melting and casting: Based on the chemical composition of the high thermal conductivity and high density aluminum alloy material, the raw materials are precisely batched, melted and refined, and then cast into alloy ingots. Homogenization treatment: The alloy ingot is subjected to homogenization heat treatment to eliminate compositional segregation inside the alloy ingot; Cold forging: The homogenized billet is placed in a room temperature environment for cold forging and plastic deformation, wherein the forging ratio is not less than 3:1, and a lubricant is applied during the deformation process to reduce deformation resistance. Solution treatment: The workpiece after cold forging is heated to the solution temperature and held for heat treatment, followed by quenching.

[0009] Aging treatment: The workpiece after solution quenching is subjected to a two-stage aging treatment to precipitate strengthening phases.

[0010] Preferably, the two-stage aging treatment of the workpiece after solution quenching to precipitate strengthening phases includes: The first level of aging is to keep warm at 120℃±3℃ for 2 hours; After the first level of timeliness is completed, the second level of timeliness will begin. The material was kept at 175℃±3℃ for 6 hours to improve its mechanical and thermal conductivity properties.

[0011] Preferably, before placing the homogenized billet in a room temperature environment for cold forging and plastic deformation, wherein the forging ratio is not less than 3:1 and a lubricant is applied during the deformation process to reduce deformation resistance, a preheating treatment is performed. The preheating process includes: The billet is kept at 415℃±5℃ for 2 to 3 hours; Furnace cooling shall be performed at a rate not exceeding 30°C / hour; After the billet temperature drops below 260℃, it is taken out of the furnace and then cold forging is carried out.

[0012] Preferably, the step of placing the homogenized billet in a room temperature environment for cold forging and plastic deformation, wherein the forging ratio is not less than 3:1, and a lubricant is applied during the deformation process to reduce deformation resistance, includes: The lubricant used is a composite system of phosphate saponification film and polymer lubricant.

[0013] Preferably, the process of heating the cold-forged workpiece to the solution temperature for heat treatment and then quenching includes: The cooling rate for forced water spray quenching shall not be less than 50°C / second.

[0014] Preferably, the two-stage aging treatment performed on the solution-quenched workpiece to precipitate strengthening phases includes: The two-stage aging treatment must be started within 4 hours after solution quenching to prevent abnormal transformation of the internal structure of the workpiece.

[0015] To address the aforementioned technical problems, this application provides an application of a high thermal conductivity and high density aluminum alloy material in a heat dissipation device. The high thermal conductivity and high density aluminum alloy material is rolled, punched, engraved, or stamped to form a heat dissipation interface preform. The shape of the heat dissipation interface preform is adapted to the installation space between a specific heat-generating element and a heat sink.

[0016] To solve the above-mentioned technical problems, this application provides an aluminum alloy product, which is prepared by the preparation method described above. The aluminum alloy product has a thermal conductivity of not less than 200 W / (m·K) at 25°C, a tensile strength of not less than 200 MPa, and an elongation after fracture of not less than 10%.

[0017] Preferably, the aluminum alloy product is a precision structural component manufactured using a cold forging process.

[0018] This invention discloses a high thermal conductivity and high density aluminum alloy material, its preparation method, and its application. This invention offers the following advantages: By strictly limiting the content of harmful impurity elements such as Fe, Cu, Mn, and Zn, it reduces the scattering of hot carriers by coarse intermetallic compounds and solid solution atoms. The innovative addition of trace amounts of La forms stable compounds with residual Fe and Si, purifying grain boundaries, optimizing the microstructure, and systematically reducing scattering centers. The addition of trace amounts of Cr improves corrosion resistance and resistance to stress corrosion cracking. This lays the compositional foundation for the material's high thermal conductivity and good environmental adaptability. Furthermore, through melting, casting, and homogenization treatment, this invention strictly controls the alloy composition and eliminates compositional segregation, providing a uniform billet base for subsequent cold forging, ensuring high purity and low scattering characteristics from the source. The use of large deformation cold forging with a forging ratio ≥3:1 achieves significant grain refinement and microstructure densification at room temperature. Combined with lubricant application during deformation, processing defects are effectively avoided, providing the finished product with high density and excellent surface quality. Meanwhile, this application achieves fine and uniform precipitation of the strengthening phase through the synergistic regulation of solution treatment and two-stage aging. While realizing precipitation strengthening, it minimizes the obstruction to the heat conduction path, and finally obtains a high-performance aluminum alloy material with tensile strength ≥200 MPa and thermal conductivity ≥200 W / (m·K). Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be further described below in conjunction with the accompanying drawings and embodiments. The drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort: Figure 1 This is a flowchart of a preferred embodiment of the present invention for preparing a high thermal conductivity and high density aluminum alloy material. Detailed Implementation

[0020] The core of this application is to provide a high thermal conductivity and high density aluminum alloy material, its preparation method, and its application. In this solution, the content of harmful impurity elements such as Fe, Cu, Mn, and Zn is strictly limited to reduce the scattering of hot carriers by coarse intermetallic compounds and solid solution atoms. A trace amount of La is creatively added to form stable compounds with residual Fe and Si, purifying grain boundaries, optimizing the microstructure, and systematically reducing scattering centers. Simultaneously, this application ensures compositional purity through melting, casting, and homogenization treatment, combined with large-deformation cold forging to achieve grain refinement and microstructure densification. Then, solid solution treatment and two-stage aging synergistically induce the fine and uniform precipitation of strengthening phases, ultimately yielding a high thermal conductivity and high density aluminum alloy material with a tensile strength ≥200 MPa, a thermal conductivity ≥200 W / (m·K), and excellent surface density.

[0021] All raw materials used in this invention are not particularly limited in their source; they can be purchased commercially or prepared using conventional methods well-known to those skilled in the art. The purity of the raw materials used in this invention is not particularly limited; however, analytical grade or conventional purity in the field of luminescent porous materials is preferred. All raw materials used in this invention have common designations and abbreviations in the art, each clearly defined within its relevant application area. Those skilled in the art can obtain them from commercially available sources or prepare them using conventional methods based on the designation, abbreviation, and corresponding application. All processes used in this invention have common abbreviations in the art, each clearly defined within its relevant application area. Those skilled in the art can understand the conventional process steps based on the abbreviation.

[0022] Please see Figure 1 , Figure 1 A flowchart illustrating a high thermal conductivity and high density aluminum alloy material provided in this application.

[0023] The present invention provides a high thermal conductivity and high density aluminum alloy material comprising: The chemical composition of a high thermal conductivity and high density aluminum alloy material, expressed as a percentage by mass, includes: Si: 0.3-0.6%, Mg: 0.5-0.8%, Fe: ≤ 0.08%, Cu: ≤ 0.08%, Mn: ≤ 0.005%, Cr: 0.001~0.02%, Zn: ≤ 0.008%, Ti: ≤ 0.008%, La: 0.001~0.03%, The balance consists of Al and unavoidable impurities.

[0024] In a preferred embodiment, the Fe content is ≤0.05%, and the individual content of unavoidable impurities is ≤0.008%, and the total content is ≤0.01%.

[0025] It is worth noting that this application reduces the scattering of hot carriers by coarse intermetallic compounds and solid solution atoms by strictly limiting the content of harmful impurity elements such as Fe, Cu, Mn, and Zn. The innovative addition of trace amounts of La forms stable compounds with residual Fe and Si, purifying grain boundaries, optimizing the microstructure, and systematically reducing scattering centers.

[0026] Specifically, this application creatively adds trace amounts of La, which can form stable ternary compounds with residual Fe, Si, etc., mainly including: (cubic crystal system, space group Fm-3c) Tetragonal structure), LaFeSi (tetragonal crystal system, P4 / nmm space group, layered structure) and (Orthorhombic crystal system, space group Cmcm) These compounds have high melting points and stable structures. They preferentially precipitate during the solidification process of aluminum alloys, pinning grain boundaries and refining grains. At the same time, they solidify free impurities and purify the aluminum matrix, thereby synergistically improving the thermal conductivity and density of the alloy.

[0027] This application provides a method for preparing a high thermal conductivity and high density aluminum alloy material. The method for preparing such a material includes: S1. Melting and casting: Based on the chemical composition of a high thermal conductivity and high density aluminum alloy material, the raw materials are precisely batched, melted and refined, and then cast into alloy ingots. Specifically, in this embodiment, Si and Mg are the main strengthening elements, which will form during the subsequent aging process. Strengthening phase; at the same time, this application strictly limits the content of impurities such as Fe, Cu, Mn, and Zn to prevent these elements from easily forming coarse intermetallic compounds (such as...) in the aluminum matrix. Fe and AlFeSi phases (or existing in solid solution atomic form) strongly scatter thermally conductive electrons and phonons, significantly reducing the thermal conductivity.

[0028] Specifically, in this embodiment, the addition of trace amounts of La allows it to preferentially combine with residual impurities such as Fe and Si to form stable compounds, thereby purifying the matrix and reducing obstruction to heat conduction. Simultaneously, this application removes gases and inclusions from the melt through melting, degassing, and refining processes, providing high-purity, high-density billets for subsequent processing.

[0029] S2. Homogenization treatment: The alloy ingot is subjected to homogenization heat treatment to eliminate component segregation inside the alloy ingot. Specifically, in this embodiment, during the semi-continuous casting process, due to the rapid cooling rate and the presence of a temperature gradient, dendritic segregation and non-equilibrium eutectic phases inevitably form inside the ingot. These microscopic inhomogeneities can lead to uneven deformation and even induce microcracks during subsequent cold forging. Homogenization heat treatment, through high-temperature long-term holding, utilizes atomic diffusion to redistribute solute elements in the matrix, eliminating dendritic segregation; simultaneously, it dissolves the non-equilibrium low-melting-point eutectic phase, reducing the risk of overheating during subsequent solution treatment. A billet with a homogenized microstructure undergoes more coordinated deformation during cold forging, which is beneficial for obtaining high density and uniform mechanical properties.

[0030] S3. Cold forging and pressing: The homogenized billet is placed in a room temperature environment for cold forging and pressing plastic deformation, wherein the forging ratio is not less than 3:1, and a lubricant is applied during the deformation process to reduce deformation resistance. Specifically, in this embodiment, large plastic deformation is used to refine grains, eliminate casting defects, increase material density, and achieve near-net-shape forming.

[0031] Specifically, in this embodiment, the homogenized billet is cold-forged at room temperature with a forging ratio ≥3:1, allowing for direct forging into precision structural parts with complex shapes and reducing machining. Furthermore, the combined use of a phosphate saponification film and a polymeric lubricant reduces friction, minimizes mold wear, and prevents cold welding, ensuring the achievement of large deformation.

[0032] S4. Solution treatment: The workpiece after cold forging is heated to the solution temperature and held for heat treatment, followed by quenching. Specifically, in this embodiment, the solution treatment allows the strengthening phase to fully dissolve into the aluminum matrix, forming a highly supersaturated solid solution, which prepares for subsequent aging precipitation.

[0033] S5. Aging treatment: Perform a two-stage aging treatment on the workpiece after solution quenching to precipitate strengthening phases.

[0034] Specifically, in this embodiment, the aging treatment causes the strengthening phase in the supersaturated solid solution to precipitate out in a fine and uniform form, thereby achieving precipitation strengthening while minimizing damage to thermal conductivity.

[0035] In a preferred embodiment, a two-stage aging treatment is performed on the solution-quenched workpiece to precipitate strengthening phases, including; The first level of aging is to keep warm at 120℃±3℃ for 2 hours; After the first level of timeliness is completed, the second level of timeliness will begin. The material was kept at 175℃±3℃ for 6 hours to improve its mechanical and thermal conductivity properties.

[0036] Specifically, in this embodiment, the first stage of aging is pre-aging, which is carried out at a lower temperature. The purpose is to provide uniform nucleation sites for the precipitation of strengthening phases. After solution quenching, the aluminum alloy is in an unstable state, with a supersaturated solid solution forming inside. Low-temperature holding can promote the slow diffusion of solute atoms, forming a large number of fine and uniformly distributed strengthening phase nuclei at grain boundaries and intragranular defects.

[0037] Specifically, in this embodiment, the second-stage aging process is the main aging process, where the temperature increases, accelerating the diffusion rate of solute atoms and causing the strengthening phase nuclei formed in the first stage to grow rapidly and form a stable phase. Reinforcing phase. This reinforcing phase consists of fine, dispersed hard particles that effectively hinder dislocation movement, thereby significantly improving the tensile strength, hardness, and other mechanical properties of the material.

[0038] In a preferred embodiment, before cold forging and plastic deformation of the homogenized billet at room temperature, wherein the forging ratio is not less than 3:1 and before applying a lubricant to reduce deformation resistance during the deformation process, a preheating treatment is performed. The preheating process includes: The billet is kept at 415℃±5℃ for 2 to 3 hours; Furnace cooling shall be performed at a rate not exceeding 30°C / hour; After the billet temperature drops below 260℃, it is taken out of the furnace and then cold forging is carried out.

[0039] Specifically, in this embodiment, the homogenized extruded billet typically has high hardness and poor plasticity, making it prone to cracking when directly subjected to large-deformation cold forging. In this application, the preheating treatment is equivalent to a high-temperature softening annealing. This causes the dislocations generated during cold deformation to recover and partially recrystallize, reducing the dislocation density and decreasing the material hardness.

[0040] In a preferred embodiment, the process of cold forging and plastic deformation of a homogenized billet at room temperature, wherein the forging ratio is not less than 3:1 and a lubricant is applied during the deformation process to reduce deformation resistance, includes: The lubricant used is a composite system of phosphate saponification film and polymer lubricant.

[0041] Specifically, in this embodiment, the phosphate saponification film and the polymer lubricant are used in combination to effectively reduce friction, reduce mold wear, prevent cold welding, and ensure the realization of large deformation.

[0042] In a preferred embodiment, the process of heating the cold-forged workpiece to the solution temperature for heat treatment and then quenching includes: The cooling rate for forced water spray quenching shall not be less than 50°C / second.

[0043] In a preferred embodiment, a two-stage aging treatment is performed on the workpiece after solution quenching to precipitate strengthening phases, including: The two-stage aging treatment must be started within 4 hours after solution quenching to prevent abnormal transformation of the internal structure of the workpiece.

[0044] Specifically, in this embodiment, aging is initiated within 4 hours after quenching to prevent natural aging from occurring during room temperature storage, which would lead to uneven distribution of the strengthening phase and a decrease in peak hardness during subsequent artificial aging.

[0045] This application provides an application of a high thermal conductivity and high density aluminum alloy material in a heat dissipation device. The high thermal conductivity and high density aluminum alloy material is rolled, punched, engraved or stamped to form a heat dissipation interface preform. The shape of the heat dissipation interface preform is adapted to the installation space between a specific heat-generating element and a heat sink.

[0046] To solve the above-mentioned technical problems, this application provides an aluminum alloy product, which is prepared by the preparation method described above. The aluminum alloy product has a thermal conductivity of not less than 200 W / (m·K) at 25°C, a tensile strength of not less than 200 MPa, and an elongation after fracture of not less than 10%.

[0047] As a preferred embodiment, the aluminum alloy product is a precision structural component manufactured using a cold forging process. Example

[0048] This embodiment provides a high thermal conductivity and high density aluminum alloy material, its preparation method, and its application in an optical module heat sink. The chemical composition and preparation steps of the aluminum alloy material strictly follow the technical solution of this application, as detailed below: 1. Chemical composition of aluminum alloy material (mass percentage): Si: 0.42%, Mg: 0.62%, Fe: 0.045% (≤0.05%, meeting the requirements of the preferred embodiment), Cu: 0.035%, Mn: 0.003%, Cr: 0.009%, Zn: 0.004%, Ti: 0.004%, La: 0.014%, with the balance being Al and unavoidable impurities; wherein the content of a single unavoidable impurity is ≤0.008%, and the total content is ≤0.01%.

[0049] 2. Preparation method, the specific steps are as follows: Melting and casting: Based on the above chemical composition, the raw materials are accurately proportioned and put into a medium-frequency induction melting furnace and heated to 725°C to completely melt them. During this process, a refining treatment is carried out (0.3% of the total mass of the raw materials is added as a refining agent, and the temperature is held at 712°C for 16 minutes). After refining, the mixture is left to stand for 10 minutes and then cast into alloy round ingots with a diameter of 200mm using a semi-continuous casting process.

[0050] Homogenization treatment: The above alloy ingots are placed in a box-type resistance furnace for homogenization heat treatment. The temperature is controlled at 560℃ and held for 8 hours to eliminate compositional segregation inside the ingots. After the holding period, the ingots are cooled to room temperature with the furnace.

[0051] Cold forging: First, the homogenized ingot billet is preheated and placed in an environment of 415℃ for 2.5 hours. Then, it is furnace cooled to below 200℃ at a rate of 25℃ / h and taken out of the furnace, and naturally cooled to room temperature. Then, the preheated billet is placed in a room temperature environment and plastically deformed using a multi-station cold forging press. The forging ratio is controlled at 3.5:1. During the deformation process, a composite system of phosphate saponification film and polymer lubricant is applied to reduce deformation resistance. Finally, it is forged into a light module heat sink billet.

[0052] Solution treatment: Heat the cold-forged workpiece to 535℃ and hold for 80 minutes. After holding, immediately perform forced water quenching with a cooling rate of 60℃ / s to ensure rapid cooling of the workpiece to room temperature.

[0053] Aging treatment: Within 2 hours after solution quenching, the workpiece is subjected to a two-stage aging treatment to precipitate the strengthening phase; the first stage of aging is carried out at 120℃ for 2 hours. After the first stage of aging is completed, the second stage of aging is carried out at 175℃ for 6 hours. After the holding is completed, the workpiece is air-cooled to room temperature to complete all preparation processes.

[0054] 3. Performance Testing and Application: The completed optical module heat sink was subjected to performance testing, and the results are as follows: thermal conductivity of 207 W / (m·K) (≥200 W / (m·K)) at 25℃, tensile strength of 206 MPa (≥200 MPa), and elongation after fracture of 11.8% (≥10%). This heat sink is a precision structural component formed by cold forging, which is adapted to the installation space of the heat-generating elements of the optical module and can efficiently dissipate the heat generated by the optical module during operation. Example

[0055] This embodiment provides a high thermal conductivity and high density aluminum alloy material, its preparation method, and its application in preformed heat dissipation interfaces for small communication devices, as detailed below: 1. Chemical composition of aluminum alloy material (mass percentage): Si: 0.36%, Mg: 0.56%, Fe: 0.04%, Cu: 0.025%, Mn: 0.002%, Cr: 0.006%, Zn: 0.003%, Ti: 0.003%, La: 0.011%, balance being Al and unavoidable impurities; wherein the individual content of unavoidable impurities is ≤0.008%, and the total content is ≤0.01%.

[0056] 2. Preparation method, the specific steps are as follows: Melting and casting: According to the above chemical composition, the raw materials are accurately proportioned and placed in a medium-frequency melting furnace, heated to 715℃ to melt, and then refined (0.25% of the total mass of the raw materials is added as a refining agent, and the temperature is held at 705℃ for 13 minutes). After refining, the mixture is allowed to stand for 8 minutes, and then cast into alloy round ingots with a diameter of 180mm using a semi-continuous casting process.

[0057] Homogenization treatment: The alloy ingot is placed in an electric resistance furnace and homogenized at 555°C for 7.5 hours to eliminate internal component segregation. It is then cooled to room temperature with the furnace.

[0058] Cold forging: The billet is first preheated and placed in an environment of 412℃ for 2.3 hours. It is then furnace cooled to below 190℃ at a rate of 23℃ / h and taken out of the furnace. After cooling to room temperature, it is then cold forged and plastically deformed at room temperature with a forging ratio of 3.2:1. A composite system of phosphate saponification film and polymer lubricant is used for lubrication. The forging is formed into a preform for the heat dissipation interface of a small communication device. Its shape is adapted to the installation space between the heat-generating element and the heat sink of the small communication device.

[0059] Solution treatment: The formed workpiece is heated to 532℃ and held for 76 minutes, followed by forced water quenching at a cooling rate of 56℃ / s until it reaches room temperature.

[0060] Aging treatment: Within 2.8 hours after solution quenching, a two-stage aging treatment is carried out; the first stage of aging is held at 119℃ for 2 hours, and the second stage of aging is held at 174℃ for 6 hours. After air cooling to room temperature, the preparation is completed.

[0061] 3. Performance Testing and Application: The performance test results are as follows: thermal conductivity at 25℃ is 204 W / (m·K), tensile strength is 203 MPa, and elongation after fracture is 11.6%. After finishing, this heat dissipation interface preform can be installed in small communication equipment to effectively fill the gap between the heat-generating element and the heat sink, thereby improving heat dissipation efficiency. Example

[0062] This embodiment provides a high thermal conductivity and high density aluminum alloy material, its preparation method, and its application in heat sinks for high-power electronic devices, as detailed below: 1. Chemical composition of aluminum alloy material (mass percentage): Si: 0.53%, Mg: 0.73%, Fe: 0.05%, Cu: 0.038%, Mn: 0.004%, Cr: 0.014%, Zn: 0.005%, Ti: 0.005%, La: 0.024%, with the balance being Al and unavoidable impurities; wherein the content of any unavoidable impurity is ≤0.008% and the total content is ≤0.01%.

[0063] 2. Preparation method, the specific steps are as follows: Melting and casting: According to the above chemical composition, the raw materials are put into the medium frequency melting furnace and heated to 730°C to melt. The materials are then refined (0.35% of the total mass of the raw materials is added as a refining agent, and the temperature is held at 718°C for 18 minutes). After refining, the materials are left to stand for 12 minutes and then semi-continuously cast to form alloy round ingots with a diameter of 220mm.

[0064] Homogenization treatment: The ingot is placed in a resistance furnace and homogenized at 565°C for 8.5 hours to eliminate component segregation, and then cooled to room temperature with the furnace.

[0065] Cold forging: The billet is first preheated and placed in an environment of 418℃ for 2.7 hours. It is then furnace cooled to below 210℃ at a rate of 27℃ / h and taken out of the furnace. After cooling to room temperature, it undergoes multiple cold forging plastic deformation at room temperature with a forging ratio of 3.7:1. A composite system of phosphate saponification film and polymer lubricant is used for lubrication. The forging is formed into a heat sink for high-power electronic devices, which is a precision structural part formed by cold forging.

[0066] Solution treatment: Heat the workpiece to 538℃, hold for 84 minutes, force water quenching, cooling rate 64℃ / s, and quench to room temperature.

[0067] Aging treatment: Within 1.6 hours after solution quenching, a two-stage aging treatment is carried out; the first stage of aging is held at 121℃ for 2 hours, and the second stage of aging is held at 176℃ for 6 hours, followed by air cooling to room temperature to complete the preparation.

[0068] 3. Performance Testing and Application: The performance test results are as follows: thermal conductivity at 25℃ is 211 W / (m·K), tensile strength is 209 MPa, and elongation after fracture is 10.6%, which meets the performance requirements of aluminum alloy products in this application; the heat sink is suitable for the heat dissipation requirements of high-power electronic equipment, and can quickly dissipate the large amount of heat generated during equipment operation to ensure stable operation of the equipment. Example

[0069] This embodiment provides a high thermal conductivity and high density aluminum alloy material, its preparation method, and its application in heat dissipation components of precision instruments, as detailed below: 1. Chemical composition of aluminum alloy material (mass percentage): Si: 0.48%, Mg: 0.68%, Fe: 0.035%, Cu: 0.02%, Mn: 0.0015%, Cr: 0.011%, Zn: 0.006%, Ti: 0.006%, La: 0.018%, with the balance being Al and unavoidable impurities; wherein the content of any unavoidable impurity is ≤0.008% and the total content is ≤0.01%.

[0070] 2. Preparation method, the specific steps are as follows: Melting and casting: According to the above chemical composition, the raw materials are accurately proportioned and placed in a medium-frequency melting furnace, heated to 720℃ to melt, and then refined (0.3% of the total mass of the raw materials is added as a refining agent, and the temperature is held at 710℃ for 15 minutes). After refining, the mixture is allowed to stand for 9 minutes, and then semi-continuous casting is used to form an alloy round ingot with a diameter of 190mm.

[0071] Homogenization treatment: The ingot is placed in a resistance furnace and homogenized at 558°C for 7.8 hours to eliminate component segregation. It is then cooled to room temperature with the furnace.

[0072] Cold forging: The billet is first preheated and placed in an environment of 414℃ for 2.4 hours. It is then furnace cooled to below 195℃ at a rate of 24℃ / h and taken out of the furnace. After cooling to room temperature, it is then subjected to precision cold forging and plastic deformation at room temperature with a forging ratio of 3.4:1. A composite system of phosphate saponification film and polymer lubricant is used for lubrication. The forging is formed into a heat dissipation component for precision instruments, and its shape is adapted to the installation space of the heating element of the precision instrument.

[0073] Solution treatment: Heat the formed workpiece to 536℃, hold for 79 minutes, force water spray quenching, cooling rate 59℃ / s, and quench to room temperature.

[0074] Aging treatment: Within 2.2 hours after solution quenching, a two-stage aging treatment is carried out; the first stage of aging is held at 120℃ for 2 hours, and the second stage of aging is held at 175℃ for 6 hours. After air cooling to room temperature, the preparation is completed.

[0075] 3. Performance Testing and Application: The performance test results are as follows: thermal conductivity at 25℃ is 206 W / (m·K), tensile strength is 205 MPa, and elongation after fracture is 11.5%. This heat dissipation component is a precision structural part formed by cold forging. When installed in precision instruments, it can achieve efficient heat conduction and avoid the instrument's accuracy from being affected by overheating.

[0076] It should be noted that, in this specification, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0077] The above description of the disclosed embodiments enables those skilled in the art to make or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A high thermal conductivity and high density aluminum alloy material, characterized in that, The chemical composition of the high thermal conductivity and high density aluminum alloy material, by mass percentage, specifically includes: Si: 0.3-0.6%, Mg: 0.5-0.8%, Fe: ≤ 0.08%, Cu: ≤ 0.08%, Mn: ≤ 0.005%, Cr：0.001～0.02%， Zn: ≤ 0.008%, Ti: ≤ 0.008%, La: 0.001~0.03%, The balance consists of Al and unavoidable impurities.

2. The high thermal conductivity and high density aluminum alloy material according to claim 1, characterized in that, The Fe content is ≤0.05%, and the individual content of the unavoidable impurities is ≤0.008%, and the total content is ≤0.01%.

3. A method for preparing a high thermal conductivity and high density aluminum alloy material, used to prepare the high thermal conductivity and high density aluminum alloy material as described in claim 1 or 2, characterized in that, The method for preparing a high thermal conductivity and high density aluminum alloy material includes: Melting and casting: Based on the chemical composition of the high thermal conductivity and high density aluminum alloy material, the raw materials are precisely batched, melted and refined, and then cast into alloy ingots. Homogenization treatment: The alloy ingot is subjected to homogenization heat treatment to eliminate compositional segregation inside the alloy ingot; Cold forging: The homogenized billet is placed in a room temperature environment for cold forging and plastic deformation, wherein the forging ratio is not less than 3:1, and a lubricant is applied during the deformation process to reduce deformation resistance. Solution treatment: The workpiece after cold forging is heated to the solution temperature and held for heat treatment, followed by quenching; Aging treatment: The workpiece after solution quenching is subjected to a two-stage aging treatment to precipitate strengthening phases.

4. The method for preparing a high thermal conductivity and high density aluminum alloy material according to claim 3, characterized in that, The two-stage aging treatment of the workpiece after solution quenching to precipitate strengthening phases includes: The first level of aging is to keep warm at 120℃±3℃ for 2 hours; After the first level of timeliness is completed, the second level of timeliness will begin. The material was kept at 175℃±3℃ for 6 hours to improve its mechanical and thermal conductivity properties.

5. The method for preparing a high thermal conductivity and high density aluminum alloy material according to claim 3, characterized in that, Before placing the homogenized billet in a room temperature environment for cold forging and plastic deformation, wherein the forging ratio is not less than 3:1 and a lubricant is applied during the deformation process to reduce deformation resistance, a preheating treatment is performed. The preheating process includes: The billet is kept at 415℃±5℃ for 2 to 3 hours; Furnace cooling shall be performed at a rate not exceeding 30°C / hour; After the billet temperature drops below 260℃, it is taken out of the furnace and then cold forging is carried out.

6. The method for preparing a high thermal conductivity and high density aluminum alloy material according to claim 3, characterized in that, The process of placing a homogenized billet in a room temperature environment for cold forging and plastic deformation, wherein the forging ratio is not less than 3:1, and a lubricant is applied during the deformation process to reduce deformation resistance, includes: The lubricant used is a composite system of phosphate saponification film and polymer lubricant.

7. The method for preparing a high thermal conductivity and high density aluminum alloy material according to claim 3, characterized in that, The process of heating the cold-forged workpiece to the solution temperature for heat treatment and then quenching includes: The cooling rate for forced water spray quenching shall not be less than 50°C / second.

8. The method for preparing a high thermal conductivity and high density aluminum alloy material according to claim 3, characterized in that, The two-stage aging treatment performed on the solution-quenched workpiece to precipitate strengthening phases includes: The two-stage aging treatment must be started within 4 hours after solution quenching to prevent abnormal transformation of the internal structure of the workpiece.

9. An aluminum alloy product, characterized in that, The aluminum alloy product is prepared by the preparation method described in any one of claims 3 to 8. The aluminum alloy product has a thermal conductivity of not less than 200 W / (m·K) at 25°C, a tensile strength of not less than 200 MPa, and an elongation after fracture of not less than 10%.

10. The aluminum alloy product according to claim 9, characterized in that, The aluminum alloy product is a precision structural component manufactured using a cold forging process.

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