Preparation method of high-performance multi-scale silicon carbide reinforced aluminum-based composite material
By constructing a multi-scale silicon carbide reinforcement network and hierarchical surface modification, combined with gradient porosity preforms and pressure infiltration process, the problem of the unutilized multi-scale particle synergistic effect in the prior art was solved, and the preparation of high-performance aluminum-based composite materials was realized, improving the overall performance of the material and the manufacturing efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-01-28
- Publication Date
- 2026-03-27
AI Technical Summary
Existing technologies for preparing silicon carbide particle-reinforced aluminum matrix composites have failed to effectively utilize the synergistic effect of multi-scale particles, and the interface modification design is insufficient, which limits the improvement of the strength, toughness and interface properties of the composites.
A multi-scale synergistic reinforcement network design is adopted. By treating micron, submicron and nano-sized silicon carbide particles with graded surface modification, a multi-level reinforcement network is constructed. Combined with gradient pore preforms and pressure infiltration process, high-performance near-net-shape forming of composite materials is achieved.
This study achieved synergistic optimization of the mechanical and thermophysical properties of composite materials, improving their strength, toughness, and fatigue resistance, while also improving the interfacial bonding state, ensuring the reliability of the material's performance under harsh environments, and reducing manufacturing costs.
Smart Images
Figure CN121737512A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of metal matrix composite material preparation technology, and specifically to a method for preparing a high-performance multi-scale silicon carbide reinforced aluminum matrix composite material. Background Technology
[0002] Silicon carbide particle-reinforced aluminum matrix composites are a type of metal matrix composite material with aluminum alloy as the matrix and silicon carbide particles as the reinforcing phase. They combine the lightweight and easy-to-process properties of aluminum alloys with the high stiffness, high hardness, low coefficient of thermal expansion, and high thermal conductivity of silicon carbide ceramics. Therefore, they have broad application prospects in aerospace, electronics, military equipment, and the automotive industry. Especially in critical components with stringent requirements for thermophysical and mechanical properties, such as phased array radar T / R modules, high-power electronic device packaging, and heat dissipation substrates, they are considered an ideal replacement for traditional tungsten-copper alloys and Kovar alloys.
[0003] However, existing preparation techniques still have many limitations. For example, in the literature "Research on a Novel Preparation Method of High Volume Ratio SiC Particle-Reinforced Aluminum Matrix Composites," although a vacuum self-percolation composite high-pressure infiltration technology was developed to achieve near-net-shape forming of high volume fraction composites, the reinforcing phase only used single-level silicon carbide particles of W10-W63, failing to utilize the synergistic effect of multi-scale particles. Furthermore, the particle surface was only simply cleaned without in-depth interface modification design, which limits further improvement in the strength, toughness, and interfacial properties of the composite material. Therefore, developing an efficient preparation method that can achieve multi-scale synergistic design of the reinforcing phase and fine interface control is crucial for improving the comprehensive performance of such composites and expanding their high-end applications. Summary of the Invention
[0004] To address the aforementioned problems, this invention provides a method for preparing high-performance multi-scale silicon carbide reinforced aluminum matrix composites. By constructing a multi-scale synergistic reinforcement network and implementing hierarchical surface modification, the high-performance and high-precision near-net-shape forming of the composite material is achieved.
[0005] To achieve the above objectives, the technical solution of the present invention is as follows: A method for preparing a high-performance multi-scale silicon carbide reinforced aluminum matrix composite material, comprising the following steps: S1, graded surface modification: multi-scale silicon carbide is selected for functionalized surface modification treatment, including micron-sized silicon carbide particles, submicron-sized silicon carbide particles and nano-sized silicon carbide particles. S2, Silicon Carbide Particle Mixing: The three types of silicon carbide particles after surface modification in S1 are mixed according to a preset volume fraction ratio to construct a multi-level reinforcement network and obtain graded mixed silicon carbide particles; the multi-level reinforcement network includes micron-sized silicon carbide particles as the main load-bearing skeleton, submicron-sized silicon carbide particles filling the gaps between micron-sized particles and inhibiting the agglomeration of micron-sized particles, and nano-sized silicon carbide particles realizing the functions of dislocation pinning, matrix grain refinement and microcrack bridging. S3, Preform Preparation: Graded mixed silicon carbide particles are combined with a binder and silicon carbide preforms with a preset porosity are prepared by molding process; S4, Composite molding: The aluminum matrix raw material is melted into aluminum liquid, and the aluminum liquid is fully composited with silicon carbide preforms by infiltration process to form a multi-scale silicon carbide reinforced aluminum matrix composite billet; S5, Post-processing: The composite material preform is densified and its properties are optimized to obtain silicon carbide reinforced aluminum matrix composite material.
[0006] Furthermore, in S1, the particle size of micron-sized silicon carbide particles is 10~40μm, the particle size of submicron-sized silicon carbide particles is 0.1~1μm, and the particle size of nano-sized silicon carbide particles is 10~100nm.
[0007] Furthermore, in S1, the hierarchical surface modification treatment of the micron-sized silicon carbide particles is as follows: Micron-sized silicon carbide particles are ultrasonically cleaned with hydrogen fluoride solution for 15-30 minutes to remove surface impurities, followed by chemical copper plating with a copper layer thickness controlled at 0.5-2 μm. Finally, a silane coupling agent is used for surface grafting at a temperature of 60-80℃ for 1-2 hours.
[0008] Furthermore, in S1, the hierarchical surface modification treatment of submicron-sized silicon carbide particles is as follows: Submicron-sized silicon carbide particles are surface-coated with titanate coupling agent, treated in a high-speed mixer at 60~80℃ for 1~2h, and then vacuum-dried at 100~120℃ with a vacuum degree ≤50Pa for 2~4h.
[0009] Furthermore, in S1, the hierarchical surface modification treatment of the nanoscale silicon carbide particles is as follows: The nanoscale silicon carbide particles were surface-grafted with stearic acid at a temperature of 80-100℃ for 2-3 hours. Polyvinylpyrrolidone was then added as a dispersant and ultrasonically dispersed in anhydrous ethanol at a power of 100-200W for 30-60 minutes. Finally, after centrifugation, the particles were vacuum-dried at 80-100℃ for 1-2 hours.
[0010] Furthermore, in S2, the preset volume fraction ratio is: micron-sized silicon carbide particles : submicron-sized silicon carbide particles : nano-sized silicon carbide particles = (5~7): (2~4): 1.
[0011] Furthermore, in S2, the mixing process is as follows: first, the modified micron-sized and submicron-sized silicon carbide particles are added to a high-speed mixer and mixed at a speed of 1000~1500 r / min for 30~60 min; then, the modified nano-sized silicon carbide particles are added, and argon or nitrogen gas is introduced for protection. The speed is adjusted to 800~1200 r / min and mixed for 20~40 min. During this period, ultrasonic dispersion at a power of 150~250W is performed for 15~30 min.
[0012] Furthermore, in S3, the preset porosity of the silicon carbide preform has a gradient porosity structure, and the porosity gradually increases from the surface to the interior along the direction of aluminum liquid infiltration.
[0013] Furthermore, in S4, the impregnation process is pressure impregnation, with a pressure of 5~30MPa, an impregnation temperature of 700~850℃, and a holding time of 0.5~3 hours.
[0014] Furthermore, in S5, the densification treatment is carried out by any one of hot extrusion, hot rolling or isostatic pressing.
[0015] The above approach has the following beneficial effects: 1. This scheme achieves synergistic optimization of the mechanical and thermophysical properties of composite materials by constructing a multi-scale synergistic reinforcement network of micrometer-submicrometer-nanometer. Functional design and gradation are carried out based on the characteristics of particles at each scale: micrometer-scale particles act as a rigid skeleton, primarily bearing loads and establishing material stiffness; submicrometer-scale particles fill the gaps between micrometer-scale particles, inhibiting their agglomeration and refining the matrix grains to improve material toughness; nanometer-scale particles significantly improve the material's strength and fatigue resistance through strong dislocation pinning effects and microcrack bridging. This multi-level, functionally defined reinforcement structure allows the composite material to maintain high stiffness and a low coefficient of thermal expansion while simultaneously improving its strength, toughness, and damage resistance. It overcomes the contradiction that traditional single-scale reinforced composite materials often suffer from decreased toughness with increased strength, resulting in composite materials that possess both excellent mechanical properties and structural stability.
[0016] 2. This solution employs a graded surface modification strategy, significantly improving the interfacial bonding between silicon carbide particles of various sizes and the aluminum matrix, thereby enhancing load transfer efficiency and interfacial stability. Addressing the differences in specific surface area and interfacial properties among particles of different sizes, micron-sized particles undergo electroless copper plating combined with silane coupling agent treatment, enhancing wettability while forming a strong and tough metal / ceramic interfacial layer. Submicron-sized particles are coated with titanate coupling agents to effectively prevent agglomeration during pretreatment and mixing. Nano-sized particles are grafted with stearic acid and combined with polymer dispersants, achieving highly uniform dispersion within the matrix. This precise interfacial engineering not only significantly improves the bonding strength between the reinforcing phase and the matrix, ensuring effective transfer of external loads, but also reduces performance degradation caused by interfacial reactions or debonding, thus guaranteeing the reliability of the composite material under long-term use or harsh environments.
[0017] 3. This solution combines gradient porosity preform design with near-net-shape pressure infiltration technology. While achieving high-precision forming of complex components, it ensures high material density and uniform microstructure, and reduces manufacturing costs. The gradient porosity structure designed along the infiltration direction of the preform guides the aluminum liquid to fill smoothly and sequentially, effectively avoiding defects such as pore encapsulation and incomplete infiltration that are common in traditional uniform porosity preforms. This results in a compact blank with a dense internal structure and uniformly distributed reinforcing phase. The pressure infiltration process, combined with pressure and temperature control, directly produces components with complex shapes and precise dimensions, significantly reducing subsequent machining, improving material utilization, and lowering energy consumption and processing costs. This integrated process achieves a unified forming and shaping process, providing an efficient and economical manufacturing method for the large-scale application of high-performance composite materials in precision structural components. Attached Figure Description
[0018] Figure 1 This is a schematic diagram of the method steps in an embodiment of the preparation method of the high-performance multi-scale silicon carbide reinforced aluminum matrix composite material of the present invention. Detailed Implementation
[0019] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0020] In the description of this invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.
[0022] The following detailed description illustrates the specific implementation method: Example:
[0023] As attached Figure 1 The following steps are shown: A method for preparing a high-performance multi-scale silicon carbide reinforced aluminum matrix composite material. S1, Hierarchical Surface Modification: Multi-scale silicon carbide was selected for functional surface modification treatment. The multi-scale silicon carbide included micron-sized, submicron-sized, and nano-sized silicon carbide particles. The micron-sized silicon carbide particles had a diameter of 10–40 μm, the submicron-sized particles had a diameter of 0.1–1 μm, and the nano-sized particles had a diameter of 10–100 nm. The functional surface modification treatments were as follows: Micron-sized silicon carbide particles are ultrasonically cleaned with hydrogen fluoride solution for 15-30 minutes to remove surface impurities, followed by chemical copper plating with a copper layer thickness controlled at 0.5-2 μm. Finally, a silane coupling agent is used for surface grafting at a temperature of 60-80℃ for 1-2 hours. Submicron-sized silicon carbide particles are surface-coated with titanate coupling agent, treated in a high-speed mixer at 60~80℃ for 1~2h, and then vacuum dried at 100~120℃ with a vacuum degree ≤50Pa for 2~4h. The nanoscale silicon carbide particles were surface-grafted with stearic acid at a temperature of 80-100℃ for 2-3 hours. Polyvinylpyrrolidone was then added as a dispersant and ultrasonically dispersed in anhydrous ethanol at a power of 100-200W for 30-60 minutes. Finally, after centrifugation, the particles were vacuum-dried at 80-100℃ for 1-2 hours.
[0024] S2, Silicon Carbide Particle Mixing: The three types of silicon carbide particles after surface modification in S1 are mixed according to a preset volume fraction ratio. The preset volume fraction ratio is: micron-sized silicon carbide particles: submicron-sized silicon carbide particles: nano-sized silicon carbide particles = (5~7):(2~4):1. The mixing process is as follows: First, the modified micron-sized and submicron-sized silicon carbide particles are added to a high-speed mixer and mixed at a speed of 1000~1500r / min for 30~60min. Then, the modified nano-sized silicon carbide particles are added, and argon or nitrogen gas is introduced for protection. The speed is adjusted to 800~1200r / min and mixed for 20~40min. During this period, ultrasonic dispersion at 150~250W power is used for 15~30min. A multi-level reinforcement network was constructed to obtain graded mixed silicon carbide particles. The multi-level reinforcement network includes micron-sized silicon carbide particles as the main load-bearing skeleton, submicron-sized silicon carbide particles filling the gaps between micron-sized particles and inhibiting the aggregation of micron-sized particles, and nano-sized silicon carbide particles realizing the functions of dislocation pinning, matrix grain refinement and microcrack bridging. S3, Preform Preparation: Graded mixed silicon carbide particles are combined with a binder and a molding process is used to prepare silicon carbide preforms with a preset porosity; the preset porosity of the silicon carbide preforms has a gradient pore structure, and the porosity gradually increases from the surface to the inside along the direction of aluminum liquid infiltration.
[0025] S4, Composite molding: The aluminum matrix raw material is melted into aluminum liquid, and the aluminum liquid is fully composited with the silicon carbide preform by the infiltration process. The infiltration process is pressure infiltration, the pressure of pressure infiltration is 5~30MPa, the infiltration temperature of pressure infiltration is 700~850℃, and the holding time is 0.5~3 hours to form a multi-scale silicon carbide reinforced aluminum matrix composite material blank. S5, Post-processing: The composite material preform is densified and its performance is optimized. The densification process can be carried out by any one of hot extrusion, hot rolling or isostatic pressing to obtain silicon carbide reinforced aluminum matrix composite material.
[0026] The specific implementation process is as follows: Three types of silicon carbide particles with specific particle sizes are selected as reinforcing phases: micron-sized silicon carbide particles with a particle size of 20 μm, submicron-sized silicon carbide particles with a particle size of 0.5 μm, and nanon-sized silicon carbide particles with a particle size of 50 nm, and their surface modifications are carried out in stages respectively. For 20μm micron-sized silicon carbide particles: First, they are ultrasonically cleaned in a 10% hydrogen fluoride solution for 20 minutes to thoroughly remove surface oxide layers, oil stains, and other impurities; then, chemical copper plating is performed. By controlling the concentration of the plating solution and the reaction time, a uniform copper plating layer with a thickness of 1μm is formed on the particle surface. The copper plating layer can serve as a transition layer to improve the wettability between silicon carbide and the aluminum substrate; finally, the copper-plated particles are placed in a reaction system containing a silane coupling agent and grafted at a constant temperature of 70°C for 1.5 hours to further enhance the chemical bonding force between the particles and the substrate.
[0027] For submicron-sized 0.5μm silicon carbide particles: they are added to a high-speed mixer in proportion with titanate coupling agent and stirred at high speed at 70℃ for 1.5 hours to allow the coupling agent molecules to uniformly coat the particle surface and reduce the van der Waals forces between particles; then the coated particles are placed in a vacuum drying oven and dried at 110℃ and 40Pa vacuum for 3 hours to remove residual moisture and avoid bubble defects in subsequent processes.
[0028] For 50nm silicon carbide nanoparticles: the particles were mixed with stearic acid and surface grafted at 90℃ for 2.5 hours to prevent particle aggregation through the steric hindrance effect of stearic acid molecules; then polyvinylpyrrolidone was added to the system as a dispersant, and anhydrous ethanol was poured in to form a suspension. The suspension was ultrasonically dispersed at 150W for 45 minutes to ensure uniform dispersion of the nanoparticles in the solution; finally, the particles were collected by centrifugation and vacuum dried at 90℃ for 1.5 hours to obtain well-dispersed modified silicon carbide nanoparticles.
[0029] The silicon carbide particles were mixed according to a preset volume fraction of micron-sized: submicron-sized: nano-sized = 6:3:1, i.e., 60% 20μm silicon carbide particles, 30% 0.5μm silicon carbide particles, and 10% 50nm silicon carbide particles. First, the modified 20μm micron-sized and 0.5μm submicron-sized silicon carbide particles were added to a high-speed mixer, set to a speed of 1200 rpm, and mixed continuously for 45 minutes. This allowed the submicron-sized particles to uniformly fill the gaps between the micron-sized particles, initially reducing particle agglomeration. Then… Modified 50nm nanoscale silicon carbide particles were added to the mixer, and nitrogen gas was introduced for protection to prevent the particles from being oxidized during high-speed mixing. The speed was adjusted to 1000r / min and mixing continued for 30 minutes. During this period, a 200W ultrasonic device was turned on to assist dispersion for 20 minutes. The cavitation effect of ultrasound was used to break up the tiny agglomerates of nanoparticles, and finally a graded mixed silicon carbide particle structure with "micron particles as the framework, submicron particles filling the gaps, and nanoparticles diffusely distributed" was formed, thus constructing a complete multi-level reinforcement network.
[0030] A composite binder consisting of 50% paraffin emulsion and 5% sodium carboxymethyl cellulose (CMC) was used. This CMC was thoroughly mixed with silicon carbide particles in a step-graded mixing process. Preforms were then prepared using a dry-mix extrusion molding process. The porosity gradient was controlled through mold design, resulting in an initial contact porosity of 20% for the molten aluminum, 30% for the intermediate layer, and 40% for the inner infiltration terminal. After molding, the preforms underwent drying and sintering treatment: first, the preforms were held at 60℃ for 2 hours to evaporate surface moisture and create air channels; then, they were held at 100℃ for 3 hours to remove internal moisture; subsequently, they were held at 350℃ for 2 hours to remove the paraffin emulsion; finally, the CMC was sintered at 900℃ for 3 hours, resulting in a stable silicon carbide preform with a gradient porosity. This gradient structure allows the molten aluminum to gradually overcome resistance during infiltration, smoothly filling from the surface to the interior and preventing infiltration blockage.
[0031] 6063 cast aluminum alloy was selected as the aluminum matrix raw material and heated and melted in the lower furnace of the infiltration equipment at a controlled melting temperature of 830℃ to obtain pure aluminum liquid. The prepared gradient pore preform was fixed in the upper furnace of the equipment, and the temperature of the upper furnace was controlled at 750℃ to create a reasonable temperature difference with the aluminum liquid temperature. This ensured the fluidity of the aluminum liquid while avoiding harmful reactions between silicon carbide and the aluminum matrix caused by high temperature. After evacuating the upper furnace, nitrogen gas was introduced into the lower furnace containing the aluminum liquid, applying a pressure of 20MPa. Under the action of pressure difference, the aluminum liquid rose along the riser pipe and, after contacting the surface of the preform, gradually infiltrated from the surface to the interior along the gradient pores, eventually filling all pores. The temperature and pressure were maintained for 2 hours to allow the aluminum liquid and silicon carbide particles to fully wet and combine, forming a multi-scale silicon carbide reinforced aluminum matrix composite preform.
[0032] After the composite material preform is cooled to room temperature, it is placed in a hot extrusion device for densification treatment. The hot extrusion temperature is controlled at 450℃ and the extrusion ratio is set to 5:1. The extrusion action eliminates the micropores inside the preform, making the silicon carbide particles bond more tightly with the aluminum matrix, while refining the aluminum matrix grains and improving the mechanical properties of the material.
[0033] After extrusion, the material undergoes surface cleaning to remove impurities such as oxide scale, ultimately yielding a high-performance multi-scale silicon carbide-reinforced aluminum matrix composite. This high-performance multi-scale silicon carbide-reinforced aluminum matrix composite retains the high stiffness and load-bearing capacity of micron-sized silicon carbide, while also improving density through submicron-sized particle filling and refining grains through the pinning effect of nano-sized particles. Its overall performance far surpasses that of single-scale silicon carbide-reinforced aluminum matrix composites.
[0034] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A method for producing a high performance multi-scale silicon carbide reinforced aluminum matrix composite material, characterized by, The method comprises the following steps: S1, hierarchical surface modification: selecting multi-scale silicon carbide for functional surface modification treatment, the multi-scale silicon carbide including micron-sized silicon carbide particles, sub-micron-sized silicon carbide particles and nano-sized silicon carbide particles; S2, mixing of silicon carbide particles: mixing the three types of silicon carbide particles after the surface modification treatment in S1 according to a preset volume fraction ratio, constructing a multi-level reinforced network, and obtaining graded mixed silicon carbide particles; the multi-level reinforced network including micron-sized silicon carbide particles as a main bearing framework, sub-micron-sized silicon carbide particles filling the gaps between micron-sized particles and inhibiting micron-sized particle agglomeration, and nano-sized silicon carbide particles achieving dislocation pinning, matrix grain refinement and micro-crack bridging functions; S3, preparation of a preform: combining the graded mixed silicon carbide particles with a binder, and preparing a silicon carbide preform with a preset porosity through a molding process; S4, composite molding: melting an aluminum-based matrix raw material into aluminum liquid, and fully combining the aluminum liquid with the silicon carbide preform through an infiltration process to form a multi-scale silicon carbide reinforced aluminum-based composite material blank; S5, post-processing: performing densification treatment and performance optimization treatment on the composite material blank, and obtaining a silicon carbide reinforced aluminum-based composite material.
2. The method of making a high performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 1, wherein, In S1, the particle size of the micron-sized silicon carbide particles is 10-40 μm, the particle size of the sub-micron-sized silicon carbide particles is 0.1-1 μm, and the particle size of the nano-sized silicon carbide particles is 10-100 nm.
3. The method of making a high-performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 2, wherein, In S1, the hierarchical surface modification treatment of the micron-sized silicon carbide particles is as follows: The micron-sized silicon carbide particles are ultrasonically cleaned with hydrogen fluoride solution for 15-30 min to remove surface impurities, then subjected to chemical copper plating treatment, the thickness of the copper plating layer is controlled to be 0.5-2 μm, and finally subjected to surface grafting with a silane coupling agent, the grafting temperature is 60-80 ℃, and the grafting time is 1-2 h.
4. The method of making a high-performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 3, wherein, In S1, the hierarchical surface modification treatment of the sub-micron-sized silicon carbide particles is as follows: The sub-micron-sized silicon carbide particles are coated with a titanate coupling agent in a high-speed mixer at 60-80 ℃ for 1-2 h, and then dried in a vacuum at 100-120 ℃ and a vacuum degree of ≤50 Pa for 2-4 h.
5. The method of making a high-performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 4, wherein, In S1, the hierarchical surface modification treatment of the nano-sized silicon carbide particles is as follows: The nano-sized silicon carbide particles are subjected to surface grafting modification with stearic acid at a grafting temperature of 80-100 ℃ and a grafting time of 2-3 h, then polyvinylpyrrolidone is added as a dispersant, ultrasonic dispersion is performed in anhydrous ethanol at a power of 100-200 W for 30-60 min, and finally, after centrifugal separation, vacuum drying is performed at 80-100 ℃ for 1-2 h.
6. The method of making a high-performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 5, wherein, In S2, the preset volume fraction ratio is: micron-sized silicon carbide particles: sub-micron-sized silicon carbide particles: nano-sized silicon carbide particles = (5-7):(2-4):
1.
7. The method of making a high-performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 6, wherein, In S2, the mixing process is as follows: first, the modified micron and submicron silicon carbide particles are added into a high-speed mixer and mixed at a speed of 1000-1500 r / min for 30-60 min, then the modified nano silicon carbide particles are added, argon or nitrogen is introduced for protection, the speed is adjusted to 800-1200 r / min for mixing for 20-40 min, and 150-250 W ultrasonic dispersion is performed for 15-30 min during the mixing.
8. The method of making a high-performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 7, wherein, In S3, the preset porosity of the silicon carbide preform has a gradient porosity structure, and the gradient porosity structure has a gradually increasing porosity from the surface to the inside along the aluminum liquid infiltration direction.
9. The method of making a high-performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 8, wherein, In S4, the infiltration process is pressure infiltration, the pressure of the pressure infiltration is 5-30 MPa, the infiltration temperature of the pressure infiltration is 700-850 ℃, and the holding time under pressure is 0.5-3 hours.
10. The method of making a high-performance, multi-scale silicon carbide reinforced aluminum matrix composite of claim 9, wherein, In S5, the densification treatment adopts any one of hot extrusion, hot rolling or isostatic pressing.