Aluminum-silicon carbide composite material, its preparation method and application

Abstract

This invention provides an aluminum-silicon carbide composite material, its preparation method, and its application. The aluminum-silicon carbide composite material comprises alternating layers of silicon carbide and aluminum material; the number of aluminum material layers is greater than the number of silicon carbide layers; the thickness of the silicon carbide layers is 5 μm to 0.5 mm, and the thickness of the aluminum material layers is 1 μm to 0.15 mm. This invention can reduce the thickness of the aluminum-silicon carbide composite material while simultaneously improving its mechanical strength.

Description

Technical Field

[0001] This invention belongs to the field of aluminum-based composite materials technology, specifically relating to an aluminum-silicon carbide composite material, its preparation method, and its application. Background Technology

[0002] As 3C electronic products (such as smartphones, tablets, and laptops) become thinner, lighter, and more high-performance, the performance requirements for structural support materials are increasing. Traditional metallic materials (such as stainless steel, aluminum alloys, and magnesium alloys) possess certain strength and lightweight properties, but they struggle to simultaneously meet the comprehensive demands of high specific strength, high thermal conductivity, and high specific modulus. Aluminum-silicon carbide (Al-SiC) composites have become ideal alternative materials due to their excellent specific strength, thermal conductivity, and high specific modulus. However, existing Al-SiC composites struggle to maintain excellent mechanical strength while simultaneously reducing thickness. Summary of the Invention

[0003] This invention provides an aluminum-silicon carbide composite material, its preparation method, and its application, which can reduce the thickness of the aluminum-silicon carbide composite material while improving its mechanical strength.

[0004] In one aspect, the present invention provides an aluminum-silicon carbide composite material, comprising alternating silicon carbide layers and aluminum material layers; wherein the number of aluminum material layers is greater than the number of silicon carbide layers; the thickness of the silicon carbide layers is 5 μm to 0.5 mm, and the thickness of the aluminum material layers is 1 μm to 0.15 mm.

[0005] According to one embodiment of the present invention, the silicon carbide layer comprises silicon carbide, and the volume fraction of silicon carbide in the aluminum-silicon carbide composite material is 5% to 50%; and / or, the aluminum material layer comprises aluminum material, and the volume fraction of aluminum material in the aluminum-silicon carbide composite material is 50% to 95%.

[0006] According to one embodiment of the present invention, the average particle size of the silicon carbide is 5 to 75 μm.

[0007] According to one embodiment of the present invention, the thickness of the aluminum-silicon carbide composite material is ≥0.05mm.

[0008] In another aspect, the present invention provides a method for preparing the above-mentioned aluminum-silicon carbide composite material, comprising the following steps: S1-1, providing an aluminum-silicon carbide sublayer, wherein the aluminum-silicon carbide sublayer comprises stacked silicon carbide layers and aluminum material layers; S1-2, stacking N layers of the aluminum-silicon carbide sublayer, where N≥1, such that the silicon carbide layers and the aluminum material layers are alternately arranged to obtain a first stack; S1-3, covering the surface of the outermost silicon carbide layer in the first stack with a second aluminum substrate to form a second stack; S1-4, performing a first hot pressing on the second stack to obtain the aluminum-silicon carbide composite material.

[0009] According to one embodiment of the present invention, the first hot pressing is performed under vacuum conditions; and / or, the temperature of the first hot pressing is 500-620°C; and / or, the pressure of the first hot pressing is 10-50 MPa.

[0010] According to one embodiment of the present invention, the thickness of the first aluminum substrate is 5μm-1500μm; and / or, the thickness of the second aluminum substrate is 5μm-1500μm.

[0011] According to one embodiment of the present invention, the process of providing the aluminum-silicon carbide sublayer includes: depositing silicon carbide on the surface of a first aluminum substrate to obtain a preform layer, and performing a second hot pressing on the preform layer to obtain an aluminum-silicon carbide sublayer comprising a silicon carbide layer and an aluminum material layer.

[0012] According to one embodiment of the present invention, the silicon carbide in the preform layer exists in the form of particles, and the distance between two adjacent silicon carbide particles is 0.5 to 50 μm.

[0013] According to one embodiment of the present invention, the second hot pressing is performed under vacuum conditions; and / or, the temperature of the second hot pressing is 500-620°C; and / or, the pressure of the second hot pressing is 10-50 MPa; and / or, the volume fraction of silicon carbide in the aluminum-silicon carbide sublayer is 10-75%.

[0014] According to one embodiment of the present invention, the process of depositing silicon carbide on the surface of a first aluminum substrate to obtain a preform includes: forming an adhesive layer on the surface of the first aluminum substrate, and depositing the silicon carbide on the side of the adhesive layer away from the first aluminum substrate to obtain the preform.

[0015] According to one embodiment of the present invention, the thickness of the adhesive layer is 20 to 300 μm.

[0016] In another aspect, the present invention provides a structural component comprising the aluminum-silicon carbide composite material described above or the aluminum-silicon carbide composite material prepared by the above preparation method.

[0017] In another aspect, the present invention provides an electrical device including the above-described structural components.

[0018] This invention provides an aluminum-silicon carbide composite material, its preparation method, and its applications. The aluminum-silicon carbide composite material is composed of alternating layers of silicon carbide and aluminum, with the number of aluminum layers exceeding the number of silicon carbide layers. The thickness of the silicon carbide layers is 5 μm to 0.5 mm, and the thickness of the aluminum layers is 1 μm to 0.15 mm. This aluminum-silicon carbide composite material system fully utilizes the mechanical properties of silicon carbide and the thermal conductivity of aluminum, achieving complementarity and enhancement of the properties of aluminum and silicon carbide. The layered structure effectively disperses stress, maintaining excellent tensile strength and tensile modulus even when the thickness of the aluminum-silicon carbide composite material is reduced, thereby improving the mechanical strength of the aluminum-silicon carbide composite material. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the aluminum-silicon carbide composite material in some embodiments of the present invention;

[0020] Figure 2 An optical microscope image of the aluminum-silicon carbide composite material of Example 1 of the present invention;

[0021] Explanation of reference numerals in the attached figures: 1: silicon carbide layer; 2: aluminum material layer; d1 is the thickness of the aluminum material layer; d2 is the thickness of the silicon carbide layer. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below in conjunction with the embodiments of this invention. Obviously, the described embodiments are only some embodiments of this invention, not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0023] In related technologies, Al-SiC composite materials have difficulty maintaining excellent mechanical strength and thermal conductivity while achieving thickness reduction, and this problem urgently needs to be solved.

[0024] In view of this, embodiments of the present invention provide an aluminum-silicon carbide composite material. Figure 2 The image shown is an optical microscope image of the aluminum-silicon carbide composite material of the present invention. Figure 2 As shown, the aluminum-silicon carbide composite material is composed of alternating silicon carbide layer 1 and aluminum material layer 2; the number of aluminum material layer 2 layers is greater than the number of silicon carbide layer 1 layers; the thickness of silicon carbide layer 1 is 5μm to 0.5mm, and the thickness of aluminum material layer 2 is 1μm to 0.15mm.

[0025] For example, such as Figure 1As shown, when the number of silicon carbide layers is 4 and the number of aluminum material layers is 5, the aluminum-silicon carbide composite material has a layered structure consisting of alternating silicon carbide layer 1 and aluminum material layer 2. d1 is the thickness of the aluminum material layer; d2 is the thickness of the silicon carbide layer.

[0026] This invention employs a layered structure with alternating silicon carbide layer 1 and aluminum material layer 2, controlling the thickness of the silicon carbide layer within the range of 5μm to 0.5mm and the thickness of the aluminum material layer within the range of 1μm to 0.15mm. This allows for the reduction of the thickness of the aluminum-silicon carbide composite material while simultaneously improving its mechanical strength. The reasons are as follows: 1) By alternating the silicon carbide and aluminum material layers, the mechanical properties of silicon carbide and the thermal conductivity of aluminum can be fully utilized, achieving complementarity and enhancement of the properties of silicon carbide and aluminum; 2) The layered structure can effectively disperse stress, helping to maintain excellent specific strength and specific modulus even when the thickness of the aluminum-silicon carbide composite material is reduced. 3) The number of aluminum material layers is greater than the number of silicon carbide layers. The silicon carbide layer is covered by the aluminum material layer, which prevents the silicon carbide from falling off due to direct exposure to the external environment. In addition, the aluminum material layer has better processing performance, which facilitates subsequent surface treatment processes such as anodizing. 4) By controlling the thickness of the silicon carbide layer within the range of 5μm to 0.5mm and the thickness of the aluminum material layer within the range of 1μm to 0.15mm, it is beneficial to have a good bond between the silicon carbide layer and the aluminum material layer, reduce interface defects, and thus improve the mechanical strength of the aluminum-silicon carbide composite material.

[0027] For example, the number of silicon carbide layers can be 1, 2, 3, 4, 5 or 6 layers, etc.

[0028] For example, the number of aluminum material layers can be 2, 3, 4, 5 or 6, etc.

[0029] For example, the thickness of the silicon carbide layer (referring to a single silicon carbide layer) can be 5μm, 10μm, 50μm, 100μm, 200μm, 300μm, 400μm or 0.5mm, etc.

[0030] For example, the thickness of the aluminum material layer (referring to a single aluminum material layer) can be 1μm, 5μm, 10μm, 30μm, 50μm, 70μm, 90μm, 0.1mm, 0.13mm or 0.15mm, etc.

[0031] In this embodiment of the invention, the silicon carbide layer comprises silicon carbide, and the aluminum material layer comprises aluminum material. By controlling the volume fraction of silicon carbide and the volume fraction of aluminum material in the aluminum-silicon carbide composite material, it is beneficial to further improve the mechanical strength and thermal conductivity of the aluminum-silicon carbide composite material. In some embodiments, the volume fraction of silicon carbide in the aluminum-silicon carbide composite material is 5% to 50%, and the volume fraction of aluminum material in the aluminum-silicon carbide composite material is 50% to 95%.

[0032] In this embodiment of the invention, the volume fraction of silicon carbide in the aluminum-silicon carbide composite material is (volume of silicon carbide / volume of aluminum-silicon carbide composite material) × 100%, and the volume fraction of aluminum in the aluminum-silicon carbide composite material is (volume of aluminum / volume of aluminum-silicon carbide composite material) × 100%.

[0033] For example, the volume fraction of silicon carbide in the aluminum-silicon carbide composite material can be 5%, 10%, 15%, 20%, 25%, 30%, 40%, or 50%, etc.

[0034] For example, the volume fraction of aluminum in the aluminum-silicon carbide composite material can be 50%, 60%, 70%, 80%, 90%, or 95%, etc.

[0035] In some embodiments, the silicon carbide layer comprises silicon carbide and aluminum materials.

[0036] In this embodiment of the invention, the volume fraction of silicon carbide and the volume fraction of aluminum in the aluminum-silicon carbide composite material can be calculated by measuring the density of the composite material and then using the following formula: ρ1=ρ 2. x+ρ 3. (1-x), where ρ1 is the density of the aluminum-silicon carbide composite material, ρ2 is the density of the aluminum material, ρ3 is the density of the silicon carbide, x is the volume fraction of the aluminum material in the aluminum-silicon carbide composite material, and 1-x is the volume fraction of the silicon carbide in the aluminum-silicon carbide composite material.

[0037] In some embodiments, the average particle size of silicon carbide is 5–75 μm, for example, it can be 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 40 μm, 50 μm, 60 μm, or 75 μm. This facilitates synergistic reinforcement of the interface bonding between the silicon carbide layer and the aluminum layer, reduces interface defects, and simultaneously optimizes the reinforcing effect and densification degree of the aluminum-silicon carbide composite material, thereby significantly improving the mechanical strength of the aluminum-silicon carbide composite material.

[0038] This invention allows for the determination of the average particle size of silicon carbide using conventional testing methods in the art. Specifically, the aluminum-silicon carbide composite material can be crushed and ground into powder. This powder is then placed in an acidic or alkaline solution and heated until the aluminum in the composite material is completely dissolved. After filtration and drying, silicon carbide is obtained, and its average particle size is measured using a laser particle size analyzer. The acidic solution may include hydrochloric acid, and the alkaline solution may include sodium hydroxide solution.

[0039] In some embodiments, the thickness of the aluminum-silicon carbide composite material is ≥0.05mm, for example, it can be 0.05mm, 0.06mm, 0.09mm, 0.12mm, 0.15mm, 0.2mm, 0.3mm or 0.4mm, etc.

[0040] This invention also provides a method for preparing the above-mentioned aluminum-silicon carbide composite material, comprising the following steps: S1-1, providing an aluminum-silicon carbide sublayer, the aluminum-silicon carbide sublayer comprising stacked silicon carbide layers and aluminum material layers; S1-2, stacking N layers of aluminum-silicon carbide sublayers, N≥1, such that the silicon carbide layers and aluminum material layers are alternately arranged to obtain a first stack; S1-3, covering the surface of the outermost silicon carbide layer in the first stack with a second aluminum substrate to form a second stack; S1-4, performing a first hot pressing on the second stack to obtain the aluminum-silicon carbide composite material.

[0041] In related technologies, the preparation method of aluminum-silicon carbide composite materials usually adopts powder metallurgy forming process and processes such as extrusion and rolling to produce aluminum-silicon carbide composite materials. However, due to the poor deformability of Al-SiC composite materials, the rolling pressure and yield of each rolling are low. In addition, the preparation of Al-SiC composite materials involves multiple steps, resulting in a long process cycle and high cost. Compared with the traditional powder metallurgy process for preparing aluminum-silicon carbide composite materials, the above-mentioned preparation method has the following advantages: 1) Short preparation cycle: the preparation cycle of aluminum-silicon carbide composite materials by this invention is shortened from 30-40 days to 1-3 days; 2) Simple preparation process: no need for expensive equipment such as rolling mills, extruders, cold and hot heat exchangers, etc., reducing equipment costs; 3) The utilization rate of aluminum-silicon carbide composite materials is increased from 30-40% to 95%, reducing raw material costs.

[0042] In some embodiments, the first hot pressing is performed under vacuum conditions. The vacuum environment can effectively reduce the oxidation reaction of aluminum and SiC at high temperatures, thereby improving the purity and interfacial bonding quality of the aluminum-silicon carbide composite material. Furthermore, the first hot pressing under vacuum conditions can more effectively eliminate pores and voids inside the material, improving the density and mechanical properties of the aluminum-silicon carbide composite material.

[0043] By controlling the temperature of the first hot pressing to 500-620℃ and the pressure to 10-50MPa, it is beneficial to promote the interfacial bonding between the aluminum substrate (first aluminum substrate and / or second aluminum substrate) and silicon carbide, which helps to reduce interfacial defects and improve the overall strength and structural stability of the aluminum-silicon carbide composite material. In some embodiments, the temperature of the first hot pressing is 500-620℃ and the pressure is 10-50MPa.

[0044] For example, the temperature of the first hot pressing can be 500°C, 530°C, 560°C, 590°C, 610°C or 620°C, etc.

[0045] For example, the pressure of the first hot pressing can be 10MPa, 20MPa, 30MPa, 40MPa or 50MPa, etc.

[0046] In some embodiments, the thickness of the first aluminum substrate is 5μm-1500μm and the thickness of the second aluminum substrate is 5μm-1500μm, which is beneficial to further improve the mechanical strength and thermal conductivity of the aluminum-silicon carbide composite material.

[0047] For example, the thickness of the first aluminum substrate can be 5μm, 15μm, 25μm, 35μm, 50μm, 100μm, 300μm, 500μm, 700μm, 900μm, 1000μm, 1200μm or 1500μm, etc.

[0048] For example, the thickness of the second aluminum substrate can be 5μm, 15μm, 25μm, 35μm, 50μm, 100μm, 300μm, 500μm, 700μm, 900μm, 1000μm, 1200μm or 1500μm, etc.

[0049] In some embodiments, the first aluminum substrate and / or the second aluminum substrate includes one or more of aluminum foil, aluminum alloy foil, and aluminum plate. Specifically, it includes one or more of the following: 1-series aluminum alloys (aluminum content of 99% by mass), 2-series aluminum alloys (aluminum-copper alloy), 3-series aluminum alloys (aluminum-manganese alloy), 4-series aluminum alloys (aluminum-silicon alloy), 5-series aluminum alloys (aluminum-magnesium alloy), 6-series aluminum alloys (aluminum-magnesium-silicon alloy), 7-series aluminum alloys (aluminum-zinc-magnesium-copper alloy), or 8-series aluminum alloys (aluminum-iron-lithium alloy).

[0050] In some embodiments, when the number of silicon carbide layers N=1, the preparation method of the aluminum-silicon carbide composite material includes the following steps: S2-1, laying silicon carbide on the surface of a first aluminum substrate, and then covering the second aluminum substrate with silicon carbide to form a laminated substrate; S2-2, performing a first hot pressing on the laminated substrate to obtain an aluminum-silicon carbide composite material in which silicon carbide layers and aluminum material layers are alternately arranged.

[0051] In this embodiment of the invention, when the number of silicon carbide layers N≥2, the preparation method of the aluminum-silicon carbide composite material includes the following steps: S3-1, silicon carbide is laid on the surface of the first aluminum substrate to obtain a preform layer, and the preform layer is subjected to a second hot pressing to obtain an aluminum-silicon carbide sublayer containing a silicon carbide layer and an aluminum material layer; S3-2, N1 layers of aluminum-silicon carbide sublayers are stacked, N1≥2, so that the silicon carbide layer and the aluminum material layer are alternately arranged to obtain a first stack; S3-3, a second aluminum substrate is covered on the outer silicon carbide layer of the first stack to form a second stack; S3-4, the second stack is subjected to a first hot pressing to obtain the aluminum-silicon carbide composite material.

[0052] In some embodiments, the silicon carbide in the preform layer exists in the form of particles, with the distance between two adjacent silicon carbide particles ranging from 0.5 to 50 μm, for example, 0.5 μm, 5 μm, 10 μm, 15 μm, 20 μm, 25 μm, 30 μm, 40 μm, or 50 μm. This facilitates the uniform distribution of silicon carbide in the aluminum material, ensures uniform stress transmission in the aluminum-silicon carbide composite material, and helps to further improve the mechanical strength of the aluminum-silicon carbide composite material.

[0053] In this embodiment of the invention, the distance between two adjacent silicon carbide particles in the preform layer can be measured by conventional testing methods in the art, such as scanning electron microscopy (SEM).

[0054] In some embodiments, the second hot pressing is performed under vacuum conditions. The vacuum environment can effectively reduce the oxidation reaction of aluminum and SiC at high temperatures, thereby improving the purity and interfacial bonding quality of the aluminum-silicon carbide composite material. Furthermore, performing the first and / or second hot pressing under vacuum conditions can more effectively eliminate pores and voids inside the material, improving the density and mechanical properties of the aluminum-silicon carbide composite material.

[0055] By controlling the temperature of the second hot pressing to 500-620℃ and the pressure to 10-50MPa, it is beneficial to promote interfacial bonding between the first aluminum substrate and silicon carbide, which helps to reduce interfacial defects and improve the overall strength and structural stability of the aluminum-silicon carbide composite material. In some embodiments, the temperature of the second hot pressing is 500-620℃ and the pressure is 10-50MPa.

[0056] For example, the temperature of the second hot pressing can be 500°C, 530°C, 560°C, 590°C, 610°C or 620°C, etc.

[0057] For example, the pressure of the second hot pressing can be 10MPa, 20MPa, 30MPa, 40MPa or 50MPa, etc.

[0058] In some embodiments, the volume fraction of silicon carbide in the aluminum-silicon carbide sublayer is 10-75%, for example, it can be 10%, 20%, 30%, 40%, 50%, 60% or 75%, which is beneficial to further improve the mechanical strength and thermal conductivity of the aluminum-silicon carbide composite material.

[0059] In some embodiments, the process of depositing silicon carbide on the surface of a first aluminum substrate to obtain a preform includes: forming an adhesive layer on the surface of the first aluminum substrate, and depositing silicon carbide on the side of the adhesive layer opposite to the first aluminum substrate to obtain the preform. The adhesive layer provides an adhesion interface, allowing the silicon carbide to adhere firmly to the surface of the aluminum substrate, preventing it from falling off during subsequent processing. Furthermore, the adhesive layer can limit the number of SiC layers to 1-2, avoiding excessive accumulation of SiC particles and reducing the porosity of the SiC layers, thereby further improving the density of the aluminum-silicon carbide composite material. In addition, during the subsequent first hot pressing process, the colloid in the adhesive layer completely decomposes and volatilizes.

[0060] In some embodiments, the adhesive layer includes a colloid, which can be an organic adhesive that can decompose and volatilize at high temperatures (500-620°C). For example, organic adhesives include one or more of atomized adhesives, double-sided tapes, solid adhesives, two-component adhesives (AB adhesives), and resin adhesives.

[0061] In some embodiments, the thickness of the adhesive layer is 20 to 300 μm, for example, it can be 20 μm, 50 μm, 100 μm, 200 μm or 300 μm.

[0062] This invention also provides a structural component comprising the aforementioned aluminum-silicon carbide composite material or the aluminum-silicon carbide composite material prepared by the aforementioned method. This structural component has the same advantages as the aforementioned aluminum-silicon carbide composite material, which will not be elaborated upon here.

[0063] In some implementations, the structural components include disassembled parts of the phone battery compartment.

[0064] This invention also provides an electrical device including the aforementioned structural component. This electrical device has the same advantages as the aforementioned structural component, which will not be elaborated upon here.

[0065] In some implementations, the electrical equipment includes 3C electronic products, such as smartphones, tablets, and laptops.

[0066] The present invention will be further described below through specific embodiments.

[0067] Example 1

[0068] The preparation method of the aluminum-silicon carbide composite material in this embodiment includes the following steps: Applying double-sided adhesive to a 0.15mm thick 6061 aluminum alloy plate (i.e., the first aluminum substrate) to form an adhesive layer (i.e., a double-sided adhesive layer) with a thickness of 100μm. Spreading SiC powder on the side of the adhesive layer away from the first aluminum substrate to obtain a preform layer, the SiC powder having an average particle size of 75μm. Placing the preform layer into a mold, and covering the SiC powder of the preform layer with a 0.15mm thick 6061 aluminum alloy plate (i.e., the second aluminum substrate), and performing a first hot-pressing under vacuum conditions to obtain the Al-SiC composite material. The first hot-pressing temperature is 550℃, the first hot-pressing pressure is 30MPa, and the thickness of the Al-SiC composite material is 0.32mm.

[0069] Example 2

[0070] The preparation method of the aluminum-silicon carbide composite material in this embodiment includes the following steps: Applying double-sided adhesive to a 0.1 mm thick 6061 aluminum alloy plate (i.e., the first aluminum substrate) to form an adhesive layer (i.e., a double-sided adhesive layer is formed on the surface of the first aluminum substrate), with a thickness of 100 μm. Laying SiC powder on the side of the adhesive layer away from the first aluminum substrate to obtain a preform layer, the SiC powder having an average particle size of 50 μm. Placing the preform layer into a mold and performing a second hot-pressing under vacuum conditions to obtain an Al-SiC sublayer. Stacking three of the above Al-SiC sublayers to obtain a first stack. Covering the outermost silicon carbide layer in the first stack with a 0.1 mm thick 6061 aluminum alloy plate (i.e., the second aluminum substrate) to obtain a second stack. Performing a first hot-pressing under vacuum conditions on the second stack to obtain the Al-SiC composite material. The second hot pressing temperature is 550℃, the second hot pressing pressure is 30MPa, the Al-SiC composite material thickness is 0.405mm, the first hot pressing temperature is 580℃, and the first hot pressing pressure is 40MPa.

[0071] Example 3

[0072] The preparation method of the aluminum-silicon carbide composite material in this embodiment includes the following steps: Double-sided adhesive is used to coat a 5μm thick 6061 aluminum sheet (i.e., the first aluminum substrate) with adhesive (i.e., forming an adhesive layer on the surface of the first aluminum substrate; the adhesive is an atomized adhesive), the thickness of which is 50μm. SiC powder is spread on the side of the adhesive layer away from the first aluminum substrate to obtain a preform layer, the average particle size of which is 5μm. The preform layer is placed in a mold and subjected to a second hot pressing under vacuum conditions to obtain an Al-SiC sublayer. Ten layers of the above Al-SiC sublayers are stacked to obtain a first stack. A 5μm thick 6061 aluminum sheet (i.e., the second aluminum substrate) is then covered on the outer silicon carbide layer of the first stack to obtain a second stack. The second stack is subjected to a first hot pressing under vacuum conditions to obtain the Al-SiC composite material. The second hot pressing temperature is 550℃, the second hot pressing pressure is 30MPa, the Al-SiC composite material thickness is 0.14mm, the first hot pressing temperature is 580℃, and the first hot pressing pressure is 20MPa.

[0073] Examples 4-7 and Comparative Examples 1-3: The differences from Example 2 are as follows: the type of the first aluminum substrate, the type of the second aluminum substrate, the thickness of the first aluminum substrate, the thickness of the second aluminum substrate, the number of silicon carbide layers, the number of aluminum material layers, the thickness of the silicon carbide layer, the thickness of the aluminum material layer, the thickness of the aluminum-silicon carbide composite material, the volume fraction of silicon carbide in the aluminum-silicon carbide composite material, the volume fraction of aluminum material in the aluminum-silicon carbide composite material, the volume fraction of silicon carbide in the aluminum-silicon carbide sublayer, the average particle size of silicon carbide, and the distance between two adjacent silicon carbides in the preform layer (hereinafter referred to as the distance between two adjacent silicon carbides). For details, please refer to Tables 1 and 2. Except for the differences shown in Tables 1 and 2, the other steps and conditions are the same as in Example 2.

[0074] Example 8: The difference from Example 1 is that the thickness of the first aluminum substrate, the thickness of the second aluminum substrate, the thickness of the silicon carbide layer, the thickness of the aluminum material layer, the thickness of the aluminum-silicon carbide composite material, the volume fraction of silicon carbide in the aluminum-silicon carbide composite material, the volume fraction of aluminum material in the aluminum-silicon carbide composite material, the volume fraction of silicon carbide in the aluminum-silicon carbide sublayer, the average particle size of silicon carbide, and the distance between two adjacent silicon carbide layers are different. For details, please refer to Tables 1 and 2. Except for the differences shown in Tables 1 and 2, the other steps and conditions are the same as in Example 1.

[0075] The types of the first aluminum substrate, the types of the second aluminum substrate, the number of silicon carbide layers, the number of aluminum material layers, the thickness of the silicon carbide layer, the thickness of the aluminum material layer, the thickness of the aluminum-silicon carbide composite material, the volume fraction of silicon carbide in the aluminum-silicon carbide composite material, the volume fraction of aluminum material in the aluminum-silicon carbide composite material, the volume fraction of silicon carbide in the aluminum-silicon carbide sublayer, the temperature of the first hot pressing, the time of the first hot pressing, the temperature of the second hot pressing, the time of the second hot pressing, the thickness of the adhesive layer, the type of colloid, the average particle size of silicon carbide, and the distance between two adjacent silicon carbide layers are summarized in Tables 1 and 2. Except for the differences shown in Tables 1 and 2, the other conditions are basically the same.

[0076] Table 1

[0077]

[0078] Table 2

[0079]

[0080]

[0081] Tensile strength and tensile modulus: The tensile strength and tensile modulus of the aluminum-silicon carbide composite materials in the above embodiments and comparative examples were tested using a universal testing machine. The results are shown in Table 3.

[0082] Table 3

[0083] Tensile strength (MPa) Tensile modulus (GPa) Example 1 304 78 Example 2 335 86 Example 3 380 101 Example 4 401 114 Example 5 328 88 Example 6 292 91 Example 7 260 73 Example 8 277 76 Comparative Example 1 203 66 Comparative Example 2 255 70 Comparative Example 3 248 64

[0084] As shown in Table 3, compared with Comparative Examples 1-3, Examples 1-8, by using staggered silicon carbide layers and aluminum material layers, and controlling the thickness of the silicon carbide layer to be 5μm to 0.5mm and the thickness of the aluminum material layer to be 1μm to 0.15mm, can reduce the thickness of the aluminum-silicon carbide composite material while improving its mechanical strength.

[0085] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An aluminum-silicon carbide composite material, characterized in that, It includes alternating silicon carbide layers and aluminum material layers; the number of aluminum material layers is greater than the number of silicon carbide layers; the thickness of the silicon carbide layers is 5μm to 0.5mm, and the thickness of the aluminum material layers is 1μm to 0.15mm.

2. The aluminum-silicon carbide composite material according to claim 1, characterized in that, The silicon carbide layer comprises silicon carbide, and the volume fraction of silicon carbide in the aluminum-silicon carbide composite material is 5% to 50%. And / or, the aluminum material layer comprises aluminum material, and the volume fraction of the aluminum material in the aluminum-silicon carbide composite material is 50% to 95%.

3. The aluminum-silicon carbide composite material according to claim 1 or 2, characterized in that, The average particle size of the silicon carbide is 5–75 μm.

4. The aluminum-silicon carbide composite material according to any one of claims 1-3, characterized in that, The thickness of the aluminum-silicon carbide composite material is ≥0.05mm.

5. A method for preparing the aluminum-silicon carbide composite material according to any one of claims 1-4, characterized in that, Includes the following steps: S1-1. Provide an aluminum-silicon carbide sublayer, wherein the aluminum-silicon carbide sublayer comprises stacked silicon carbide layers and aluminum material layers; S1-2. Stack N layers of aluminum-silicon carbide sublayers, where N≥1, so that the silicon carbide layers and the aluminum material layers are arranged alternately to obtain a first stack; S1-3. Cover the outermost silicon carbide layer in the first stack with a second aluminum substrate to form a second stack; S1-4. Perform a first hot pressing on the second stack to obtain the aluminum-silicon carbide composite material.

6. The preparation method according to claim 5, characterized in that, The first hot pressing is performed under vacuum conditions; And / or, the temperature of the first hot pressing is 500-620°C; And / or, the pressure of the first hot pressing is 10-50 MPa.

7. The preparation method according to claim 5 or 6, characterized in that, The thickness of the first aluminum substrate is 5μm-1500μm; And / or, the thickness of the second aluminum substrate is 5μm-1500μm.

8. The preparation method according to any one of claims 5-7, characterized in that, The process of providing the aluminum-silicon carbide sublayer includes: depositing silicon carbide on the surface of a first aluminum substrate to obtain a preform layer, and performing a second hot pressing on the preform layer to obtain an aluminum-silicon carbide sublayer comprising a silicon carbide layer and an aluminum material layer.

9. The preparation method according to claim 8, characterized in that, The silicon carbide in the prefabricated layer exists in the form of particles, and the distance between two adjacent silicon carbide particles is 0.5 to 50 μm.

10. The preparation method according to claim 8 or 9, characterized in that, The second hot pressing is performed under vacuum conditions; And / or, the temperature of the second hot pressing is 500-620°C; And / or, the pressure of the second hot pressing is 10-50 MPa; And / or, the volume fraction of silicon carbide in the aluminum-silicon carbide sublayer is 10-75%.

11. The preparation method according to any one of claims 8-10, characterized in that, The process of depositing silicon carbide on the surface of the first aluminum substrate to obtain a prefabricated layer includes: forming an adhesive layer on the surface of the first aluminum substrate, and depositing the silicon carbide on the side of the adhesive layer away from the first aluminum substrate to obtain the prefabricated layer.

12. The preparation method according to claim 11, characterized in that, The thickness of the adhesive layer is 20–300 μm.

13. A structural component, characterized in that, Includes the aluminum-silicon carbide composite material according to any one of claims 1-4 or the aluminum-silicon carbide composite material prepared by the preparation method according to any one of claims 5-12.

14. An electrical appliance, characterized in that, Includes the structural component as described in claim 13.

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