Ceramic reinforced aluminum alloy composite material and preparation method thereof

Abstract

The invention relates to the technical field of metal materials, in particular to a ceramic reinforced aluminum alloy composite material and a preparation method thereof. The aluminum alloy composite material comprises the following raw materials in parts by weight: 75-85 parts of an aluminum alloy matrix and 10-20 parts of a ceramic reinforced phase, a preparation method of the ceramic reinforced phase comprises the following steps: step 1, adding silicon carbide and a silane coupling agent into absolute ethyl alcohol, and drying after ultrasonic dispersion; 2, dissolving tetraethoxysilane in an ethanol-water mixed solvent, adjusting the pH value to 3-4, adding the silicon carbide treated in the step 1, stirring to form sol, drying, converting into gel, and calcining to form a coating layer; step 3, dispersing the silicon carbide treated in the step 2 into water, adding nickel nitrate, uniformly stirring, adding a reducing agent, stirring for reaction, and collecting precipitate particles; and 4, adding an interface modifier, and uniformly mixing. The ceramic reinforced aluminum alloy composite material has high strength, high wear resistance and good mechanical property and thermal stability.

Description

Technical Field

[0001] This invention relates to the field of metal materials technology, specifically to a ceramic-reinforced aluminum alloy composite material and its preparation method. Background Technology

[0002] Aluminum alloys are widely used in aerospace, automotive manufacturing, and electronics industries due to their advantages such as low density, high specific strength, good corrosion resistance, and ease of processing and forming. However, the mechanical properties of traditional aluminum alloys (such as strength, wear resistance, and high-temperature stability) are limited by their intrinsic characteristics, making it increasingly difficult to meet the requirements of applications under high loads and extreme environments (such as high-speed friction and high-temperature oxidation). For example, in aerospace structural components, aluminum alloy parts need to withstand high-frequency vibrations and complex stresses; in lightweight automotive design, engine peripheral components need to possess both high strength and heat resistance; and in electronic packaging, heat dissipation components need to simultaneously meet the requirements of high thermal conductivity and structural stability.

[0003] Therefore, improving the overall performance of aluminum alloys through material composite technology has become a current research hotspot. Ceramic reinforcing phases (such as silicon carbide, alumina, and titanium carbide) are widely used as reinforcements in metal matrix composites due to their high hardness, high melting point, excellent chemical stability, and good wear resistance. Among them, silicon carbide is one of the most commonly used ceramic reinforcing phases because of its relatively good wettability with aluminum alloys, its high matching degree of thermal expansion coefficient with aluminum alloys, and its ability to significantly improve the strength, stiffness, and wear resistance of composite materials. However, directly compositing unmodified silicon carbide particles with aluminum alloys presents the following key problems:

[0004] (1) Insufficient interfacial bonding strength

[0005] Aluminum alloys are liquid metals with significantly different physicochemical properties from ceramics (e.g., large wetting angle and low interfacial reactivity). This leads to the formation of weak interfacial bonds between ceramic particles and the aluminum alloy matrix during the composite process. Such weak interfaces not only fail to effectively transfer loads but may also become the source of crack initiation and propagation, significantly reducing the mechanical properties of the composite material (e.g., tensile strength and fracture toughness).

[0006] (2) Uneven dispersion of ceramic particles

[0007] Unmodified ceramic particles have high surface energy and are prone to agglomeration in aluminum alloy melts, resulting in uneven distribution within the matrix. Localized high-concentration ceramic particle areas can cause stress concentration, while low-concentration areas cannot fully exert their reinforcing effect, ultimately affecting the overall performance consistency of the composite material.

[0008] (3) Interfacial reaction and compatibility issues

[0009] During high-temperature composite processes (such as casting), active elements in aluminum alloys (such as magnesium and silicon) may react with ceramic particles (such as silicon carbide) at the interface to generate brittle phases. These brittle phases can reduce the reliability of the interfacial bonding and even deteriorate the ductility and fatigue performance of the composite material.

[0010] Therefore, how to solve the problems of poor wettability and easy occurrence of harmful interfacial reactions between ceramic particles and aluminum alloy matrix, and prepare an aluminum alloy composite material with high strength, high wear resistance, good mechanical properties and thermal stability, has become an urgent problem to be solved. Summary of the Invention

[0011] To address the aforementioned technical problems, this invention provides a ceramic-reinforced aluminum alloy composite material and its preparation method. The ceramic-reinforced aluminum alloy composite material provided by this invention systematically solves the technical challenges of poor wettability and easy occurrence of harmful interfacial reactions between ceramic particles and the aluminum alloy matrix through multi-level, composite ceramic reinforcing phase surface modification. The prepared aluminum alloy composite material exhibits high strength, high wear resistance, and good mechanical properties and thermal stability.

[0012] The technical solution of the present invention to solve the above problems is as follows:

[0013] A ceramic-reinforced aluminum alloy composite material comprises the following raw materials in parts by weight: 75-85 parts of aluminum alloy matrix and 10-20 parts of ceramic reinforcing phase.

[0014] The method for preparing the ceramic reinforcing phase includes the following steps:

[0015] Step 1: Place silicon carbide and silane coupling agent in a container, add anhydrous ethanol, and ultrasonically disperse at a power of 200-400W, a frequency of 30-40kHz, for 20-40 minutes, with the temperature controlled at 50-70℃. After ultrasonication, dry the mixture at 60-80℃ for 3-5 hours to remove the ethanol and obtain silicon carbide with coupling agent attached to its surface.

[0016] Step 2: Dissolve tetraethyl orthosilicate in an ethanol-water mixture and stir at 200-400 rpm until homogeneous. Adjust the pH of the solution to 3-4 with dilute nitric acid, add the silicon carbide treated in Step 1, and stir in a water bath at 60-80℃ for 2-4 hours to form a homogeneous sol. Dry the sol at 80-120℃ for 12-24 hours to convert it into a gel. Calcinate the gel at 400-600℃ for 1-3 hours to form a nano-silica coating layer.

[0017] Step 3: Disperse the silicon carbide treated in step 2 in deionized water, add nickel nitrate, stir evenly at 200-300 rpm, then add sodium borohydride as a reducing agent, stir continuously at 20-25℃ for 30-60 minutes, filter to collect precipitated particles, wash with deionized water, and dry at 60-80℃ for 2-4 hours to obtain silicon carbide with surface-deposited active metal.

[0018] Step 4: Add an interface modifier to the silicon carbide treated in step 3, then add deionized water or ethanol, ultrasonically disperse and mix evenly, and dry at 60-80℃ for 2-4 hours to obtain the final product.

[0019] Further, in step 1, the mass ratio of silicon carbide to silane coupling agent (KH550 or KH560, preferably KH550) is 100:0.5-1.5, and the mass-volume ratio of silicon carbide to anhydrous ethanol is 100g:500-1000ml.

[0020] Further, in step 2, the mass ratio of silicon carbide and tetraethyl orthosilicate treated in step 1 is 100:5-10, and the mass-volume ratio of tetraethyl orthosilicate to ethanol-water mixed solvent is 5-10g:80-120ml, wherein the volume ratio of ethanol to water in the ethanol-water mixed solvent is 9:1-2.

[0021] Further, in step 3, the mass-to-volume ratio of silicon carbide treated in step 2 to deionized water is 1g:10-20ml, the mass ratio of silicon carbide treated in step 2 to nickel nitrate is 100:5-10, and the molar ratio of the reducing agent to nickel ions is 1.5-2:1.

[0022] Further, in step 4, the mass ratio of silicon carbide treated in step 3 to the interface modifier is 1:0.05-0.1, the interface modifier includes silane coupling agent and nano rare earth oxide, and the mass-volume ratio of silicon carbide treated in step 3 to deionized water or ethanol is 1g:8-12mL.

[0023] Furthermore, the interface modifier is a mixture of silane coupling agent and nano-rare earth oxide in a mass ratio of 0.5-2:0.2-1, wherein the silane coupling agent is KH550 and the nano-rare earth oxide is nano-yttrium trioxide or cerium dioxide.

[0024] Furthermore, the interface modifier is prepared by modifying and pretreating a silane coupling agent and nano-rare earth oxides, and the modification and pretreating method is as follows:

[0025] Step a: Dissolve the silane coupling agent and polyethylene glycol in anhydrous ethanol, stir at 60-80℃ and 200-400 rpm for 40-80 minutes, and then let it stand for 30-60 minutes to obtain a light yellow transparent pre-assembled liquid.

[0026] Step b: Disperse the nano-rare earth oxides in anhydrous ethanol, add aluminum zirconium coupling agent, and stir at 60-80℃ and 200-400rpm for 1-2 hours to obtain a mixture. Then, add the mixture to the pre-assembled liquid obtained in step a, continue stirring for 30-60 minutes, and then let it stand at 20-25℃ for 1-2 hours to obtain the pre-assembled composite.

[0027] Step c: Dissolve nano-silver and silane coupling agent in anhydrous ethanol, and ultrasonically disperse at 50-70℃ for 10-20 minutes to obtain a dispersion. Add the pre-assembled composite obtained in step b to the dispersion, continue ultrasonic dispersion for 20-30 minutes, dry at 50-70℃ for 2-4 hours, remove ethanol, and obtain the pretreated composite interface modifier.

[0028] Further, in step a, the mass ratio of the silane coupling agent to polyethylene glycol is 40-60:10-20, and the mass-volume ratio of the silane coupling agent to anhydrous ethanol is 1g:3-5ml.

[0029] Further, in step b, the mass ratio of nano-rare earth oxide to aluminum zirconium coupling agent is 100:1-3, the mass ratio of the pre-assembled liquid to nano-rare earth oxide is 1:0.2-0.3, the mass-volume ratio of nano-rare earth oxide to ethanol is 1g:8-12ml, and the nano-rare earth oxide is nano-yttrium trioxide or cerium dioxide.

[0030] Further, in step c, the mass ratio of the nano-silver to the silane coupling agent is 1-1.3:1, and the mass-volume ratio of the nano-silver to anhydrous ethanol is 1g:10-20ml.

[0031] The preparation method of the above-mentioned ceramic-reinforced aluminum alloy composite material includes the following steps:

[0032] Step A: Melt the aluminum alloy matrix at 700-750℃ and hold for 10-30 minutes, then pass argon or nitrogen gas through it for degassing and refining for 10-20 minutes, and finally let it stand for 5-15 minutes to remove slag.

[0033] Step B: Heat the aluminum alloy melt to 720-760℃, add the ceramic reinforcing phase in 2-3 batches, with an interval of 3-5 minutes between each addition, while stirring at 300-500 rpm. After each addition, stir for 15-20 minutes to obtain the composite melt.

[0034] Step C: Pour the composite melt into a metal mold preheated to 200-250℃, cool to room temperature and demold, then solution treat at 500-550℃ for 1-2 hours, water quench, then hold at 175-185℃ for 4-8 hours, and air cool to obtain the final product.

[0035] The present invention has the following beneficial effects:

[0036] The ceramic-reinforced aluminum alloy composite material provided by this invention systematically solves the technical problems of poor wettability and easy occurrence of harmful interfacial reactions between ceramic particles and aluminum alloy matrix through multi-level, composite ceramic reinforcing phase surface modification. The prepared aluminum alloy composite material has high strength, high wear resistance, and good mechanical properties and thermal stability. In the preparation of the nano-reinforcing phase, in step 1, one end of the silane coupling agent molecule is a siloxane alkyl group that can react with the hydroxyl groups on the surface of silicon carbide, and the other end is an amino group. It forms an organic molecular film on the surface of silicon carbide particles through chemical bonding. This organic film improves the dispersibility of silicon carbide in the subsequent solution system (ethanol-water), prevents particle agglomeration, and lays the foundation for subsequent uniform coating. After the amino group of the silane coupling agent is protonated, it becomes positively charged and electrostatically attracts the oligomers generated by the hydrolysis of tetraethyl orthosilicate in step 2, which is conducive to the formation of a denser and more uniform silica coating layer. In step 2, an amorphous nano-silica layer is coated on the surface of silicon carbide by the sol-gel method. Silica exhibits significantly higher chemical stability than silicon carbide in molten aluminum alloys (typically above 700°C). This coating layer forms a diffusion barrier, effectively preventing direct contact between the molten aluminum and silicon carbide particles, greatly suppressing interfacial reactions and the formation of brittle phases, thereby enhancing the mechanical properties and corrosion resistance of the composite material. Simultaneously, amorphous silica possesses a certain degree of plasticity, which can buffer the micro-stress generated during preparation and stress application due to the mismatch in thermal expansion coefficients between aluminum and silicon carbide, reducing stress concentration at the interface and improving interfacial bonding strength and material toughness. Step 3 involves depositing nanoscale nickel particles on the surface of the silica coating layer using a chemical reduction method. The excellent wettability of nickel with molten aluminum significantly reduces the contact angle between the molten aluminum and the reinforcing phase, allowing the molten aluminum to easily spread and encapsulate the ceramic particles. Upon addition to the melt, the surface nickel layer dissolves into the molten aluminum and reacts with it, generating high-strength intermetallic compounds in situ. This achieves a transformation from simple physical bonding to metallurgical bonding between the reinforcing phase and the matrix, greatly enhancing the interfacial adhesion. At the same time, the rough metal deposit layer also increases the mechanical engagement with the substrate.

[0037] Furthermore, when the interface modifier in step 4 is a direct mixture of silane coupling agent and nano-rare earth oxides, the silane coupling agent acts as a "medium," binding one end of its functional groups to the nickel layer or oxide surface deposited in step 3, while the other end interacts with the molten aluminum, further improving wettability and dispersibility. At high temperatures, trace amounts of rare earth elements in the nano-rare earth oxides can dissolve in the aluminum matrix, playing a role in grain refinement and melt purification (e.g., hydrogen adsorption, oxygen fixation). The nano-rare earth oxides may undergo a reduction reaction at the aluminum melt interface, generating active rare earth atoms that accumulate at the interface, further increasing the interfacial energy, promoting wettability, and pinning grain boundaries and phase boundaries, thus enhancing the material's thermal stability. This interface modifier is simple to prepare, relatively low in cost, and can improve interface and matrix properties to a certain extent.

[0038] Furthermore, when the interface modifier is prepared by modifying and pretreating silane coupling agents and nano-rare earth oxides, in step a, the silane coupling agent and polyethylene glycol are initially bonded in anhydrous ethanol through hydrogen bonds / van der Waals forces to form a pre-assembled composite with dual "wetting-dispersing" functions. The silane groups provide reactivity with the hydroxyl groups on the surface of ceramic particles, while the flexible segments of PEG reduce the surface energy of the particles and inhibit aggregation through steric hindrance, providing a stable carrier for subsequent loading of nano-rare earth oxides and active metals, ensuring the uniform distribution of each functional component on the surface of the ceramic particles. In step b, through the bridging effect of the aluminum-zirconium coupling agent, the nano-rare earth oxides are firmly anchored on the silane / PEG pre-assembled network, forming a structurally stable pre-assembled composite. This step ensures that the nano-rare earth oxides can be uniformly distributed at the nanoscale on the surface of the ceramic reinforcing phase and enriched at the interface during subsequent composite processes. Through competitive reactions and interface energy regulation, the formation of harmful phases is synergistically and efficiently suppressed, while laying the foundation for strengthening interface bonding and improving load transfer efficiency. Step c introduces nano-silver to form a low-melting-point eutectic liquid phase. Silver and aluminum can form a low-melting-point eutectic phase. At the high temperature (720-760℃) during composite material preparation, nano-silver melts instantaneously and forms a transient liquid phase at the interface. This liquid phase acts like a "lubricant," greatly promoting wetting and mass transfer, accelerating the spreading of molten aluminum on the surface of the reinforcing phase, and promoting atomic diffusion at the interface, resulting in a more complete and uniform interfacial reaction and the generation of a beneficial reinforcing phase. The transient liquid phase sintering effect helps fill the interfacial micropores, forming a dense and complete interfacial transition zone. The nano-silica coating layer and active metal deposition layer on the surface of the ceramic reinforcing phase, together with the rare earth-metal intermetallic compound layer in the interface modifier, form a continuous gradient interface of "silicon carbide-nano-silica-nickel-aluminum intermetallic compound-rare earth intermetallic compound," resulting in a smooth transition of chemical composition and structure and better stress matching. The active nickel on the surface of the ceramic reinforcing phase and the rare earth metals (yttrium / cerium) in the interface modifier work together to form a multi-metallic compound network (such as nickel-aluminum, aluminum-yttrium, aluminum-cerium) in the aluminum alloy matrix. This three-dimensional chemical bonding network firmly anchors the ceramic particles within the aluminum alloy matrix. The ceramic reinforcing phase provides high modulus, high hardness, and wear resistance, while the interface modifier optimizes the interface structure to transfer loads and alleviate stress concentration. The synergistic effect of these two components enables the composite material to simultaneously possess high strength, high toughness, and good thermal stability.

[0039] In summary, this invention employs multi-level composite modification of the ceramic reinforcing phase (silicon carbide) to synergistically suppress the formation of brittle phases and significantly optimize the interfacial structure and bonding strength by forming a transient liquid phase. This approach systematically solves two key technical challenges: poor wettability between ceramic and aluminum matrix and uncontrolled interfacial reactions. The resulting composite material exhibits remarkable characteristics such as strong interfacial bonding, uniform microstructure, and excellent mechanical properties and thermal stability. Attached Figure Description

[0040] Figure 1 The graph shows the mechanical property test results of Examples 1-5 and Comparative Examples 1-3;

[0041] Figure 2 The figures show the hardness test results of Examples 1-5 and Comparative Examples 1-3. Detailed Implementation

[0042] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0043] All of the following raw materials are commercially available.

[0044] Silicon carbide, 100 mesh, 99.99% effective component content, Nangong Xindun Alloy Welding Material Spraying Co., Ltd.; Aluminum-zirconium coupling agent, Yangzhou Lida Resin Co., Ltd.; Nano silver, 20nm particle size, Beijing Zhongke Keyou Technology Co., Ltd.; Nano cerium oxide, 20nm average particle size, Hangzhou Hengge Nanotechnology Co., Ltd.; Polyethylene glycol-400, Jinan Hongteng Weiye New Material Co., Ltd.; Aluminum alloy matrix, using aluminum alloy-6061, Yifei Aluminum (Suzhou) Co., Ltd.; Nano yttrium oxide, 30nm average particle size, Qinghe Chaotai Metal Materials Co., Ltd.

[0045] Example 1

[0046] A ceramic-reinforced aluminum alloy composite material comprises the following raw materials in parts by weight: 80 parts of aluminum alloy matrix and 15 parts of ceramic reinforcing phase;

[0047] The method for preparing the ceramic reinforcing phase includes the following steps:

[0048] Step 1: Place silicon carbide and silane coupling agent KH550 in a container, add anhydrous ethanol, and ultrasonically disperse at 300W power and 35kHz frequency for 30 minutes, controlling the temperature at 60℃, so that the coupling agent uniformly coats the particle surface. After ultrasonication, dry the mixture at 70℃ for 4 hours to remove the ethanol, obtaining silicon carbide with coupling agent attached to the surface; wherein, the mass ratio of silicon carbide to silane coupling agent KH550 is 100:1, and the mass-volume ratio of silicon carbide to anhydrous ethanol is 100g:800ml;

[0049] Step 2: Dissolve tetraethyl orthosilicate in an ethanol-water mixed solvent, stir at 300 rpm until homogeneous, adjust the pH of the solution to 3-4 with 1 mol / L dilute nitric acid, add the silicon carbide treated in Step 1, stir in a 70°C water bath for 3 hours to form a homogeneous sol, dry the sol at 100°C for 18 hours to transform it into a gel, place the gel in a muffle furnace, calcine at 500°C for 2 hours to remove organic matter and form a nano-scale silica coating layer; wherein, the mass ratio of silicon carbide treated in Step 1 to tetraethyl orthosilicate (TEOS) is 100:8, the mass-volume ratio of tetraethyl orthosilicate to the ethanol-water mixed solvent is 8 g:100 ml, and the volume ratio of ethanol to water in the ethanol-water mixed solvent is 9:1.5;

[0050] Step 3: Disperse the silicon carbide treated in Step 2 in deionized water, ultrasonically disperse for 15 minutes at 200W, add nickel nitrate, stir evenly at 250rpm, then add sodium borohydride (prepared as a 5% concentration ice-water dispersion and sprayed in), stir continuously at 23℃ for 45 minutes, filter and collect the precipitated particles, wash three times with deionized water, and dry at 70℃ for 3 hours to obtain silicon carbide with surface-deposited active metal; wherein, the mass-volume ratio of silicon carbide treated in Step 2 to deionized water is 1g:15ml, the mass ratio of silicon carbide treated in Step 2 to nickel nitrate is 100:8, and the molar ratio of sodium borohydride to nickel ions is 1.8:1;

[0051] Step 4: Add an interface modifier to the silicon carbide treated in Step 3, then add deionized water or ethanol, ultrasonically disperse for 15 minutes, mix thoroughly, and dry at 70°C for 3 hours to obtain the final product. The mass ratio of the silicon carbide treated in Step 3 to the interface modifier is 1:0.08. The interface modifier is a mixture of a silane coupling agent and nano-rare earth oxides. The mass ratio of the silane coupling agent KH550 and the nano-rare earth oxide yttrium trioxide is 1.2:1.5. The mass-to-volume ratio of the silicon carbide treated in Step 3 to deionized water is 1g:10mL.

[0052] The preparation method of the above-mentioned ceramic-reinforced aluminum alloy composite material includes the following steps:

[0053] Step A involves completely melting the aluminum alloy substrate at 730℃ and holding it at that temperature for 20 minutes, then passing nitrogen gas (10L / min) through it for degassing and refining for 15 minutes, and finally letting it stand for 10 minutes to remove slag.

[0054] Step B: Heat the aluminum alloy melt to 740°C, add the ceramic reinforcing phase in three batches with a 4-minute interval between each addition, and stir at 400 rpm. Stir for 18 minutes after each addition to obtain the composite melt.

[0055] Step C: Pour the composite melt into a metal mold preheated to 220°C, cool it to room temperature and demold it, then perform a solution treatment at 530°C for 1.5 hours, immediately quench it in water (room temperature water), then hold it at 180°C for 6 hours, and finally air cool it to obtain the final product.

[0056] Example 2

[0057] A ceramic-reinforced aluminum alloy composite material comprises the following raw materials in parts by weight: 75 parts of aluminum alloy matrix and 20 parts of ceramic reinforcing phase;

[0058] The method for preparing the ceramic reinforcing phase includes the following steps:

[0059] Step 1: Place silicon carbide and silane coupling agent KH550 in a container, add anhydrous ethanol, and ultrasonically disperse at 200W power and 40kHz frequency for 20 minutes, controlling the temperature at 50℃, so that the coupling agent uniformly coats the particle surface. After ultrasonication, dry the mixture at 80℃ for 3 hours to remove the ethanol, obtaining silicon carbide with coupling agent attached to the surface; wherein, the mass ratio of silicon carbide to silane coupling agent KH550 is 100:0.5, and the mass-volume ratio of silicon carbide to anhydrous ethanol is 100g:1000ml;

[0060] Step 2: Dissolve tetraethyl orthosilicate in an ethanol-water mixed solvent, stir at 400 rpm until homogeneous, adjust the pH of the solution to 3-4 with 1 mol / L dilute nitric acid, add the silicon carbide treated in Step 1, stir in a water bath at 60°C for 4 hours to form a homogeneous sol, dry the sol at 80°C for 24 hours to transform it into a gel, place the gel in a muffle furnace, calcine at 400°C for 3 hours to remove organic matter and form a nano-scale silica coating layer; wherein, the mass ratio of silicon carbide treated in Step 1 to tetraethyl orthosilicate (TEOS) is 100:10, the mass-volume ratio of tetraethyl orthosilicate to the ethanol-water mixed solvent is 10 g:120 ml, and the volume ratio of ethanol to water in the ethanol-water mixed solvent is 9:1;

[0061] Step 3: Disperse the silicon carbide treated in Step 2 in deionized water, ultrasonically disperse for 10 minutes at 250W, add nickel nitrate, stir evenly at 200rpm, then add sodium borohydride (prepared as a 5% concentration ice-water dispersion and sprayed in), stir continuously at 25℃ for 30 minutes, filter and collect the precipitated particles, wash three times with deionized water, and dry at 60℃ for 4 hours to obtain silicon carbide with surface-deposited active metal; wherein, the mass-volume ratio of silicon carbide treated in Step 2 to deionized water is 1g:20ml, the mass ratio of silicon carbide treated in Step 2 to nickel nitrate is 100:10, and the molar ratio of sodium borohydride to nickel ions is 1.5:1;

[0062] Step 4: Add an interface modifier to the silicon carbide treated in Step 3, then add deionized water or ethanol, ultrasonically disperse for 20 minutes, mix thoroughly, and dry at 60°C for 4 hours to obtain the final product. The mass ratio of the silicon carbide treated in Step 3 to the interface modifier is 1:0.05. The interface modifier is a mixture of a silane coupling agent and nano-rare earth oxides. The mass ratio of the silane coupling agent KH550 to the nano-rare earth oxide yttrium trioxide is 0.5:0.2. The mass-to-volume ratio of the silicon carbide treated in Step 3 to deionized water is 1 g:12 mL.

[0063] The preparation method of the ceramic-reinforced aluminum alloy composite material described above is the same as in Example 1.

[0064] Example 3

[0065] A ceramic-reinforced aluminum alloy composite material comprises the following raw materials in parts by weight: 85 parts of aluminum alloy matrix and 10 parts of ceramic reinforcing phase;

[0066] The method for preparing the ceramic reinforcing phase includes the following steps:

[0067] Step 1: Place silicon carbide and silane coupling agent KH550 in a container, add anhydrous ethanol, and ultrasonically disperse at 400W power and 30kHz frequency for 40 minutes, controlling the temperature at 50℃, so that the coupling agent uniformly coats the particle surface. After ultrasonication, dry the mixture at 60℃ for 5 hours to remove the ethanol, obtaining silicon carbide with coupling agent attached to the surface; wherein, the mass ratio of silicon carbide to silane coupling agent KH550 is 100:1.5, and the mass-volume ratio of silicon carbide to anhydrous ethanol is 100g:500ml;

[0068] Step 2: Dissolve tetraethyl orthosilicate in an ethanol-water mixed solvent, stir at 200 rpm until homogeneous, adjust the pH of the solution to 3-4 with 1 mol / L dilute nitric acid, add the silicon carbide treated in Step 1, stir in an 80°C water bath for 2 hours to form a homogeneous sol, dry the sol at 120°C for 12 hours to transform it into a gel, place the gel in a muffle furnace, calcine at 600°C for 1 hour to remove organic matter and form a nano-scale silica coating layer; wherein, the mass ratio of silicon carbide treated in Step 1 to tetraethyl orthosilicate (TEOS) is 100:5, the mass-volume ratio of tetraethyl orthosilicate to the ethanol-water mixed solvent is 5 g:80 ml, and the volume ratio of ethanol to water in the ethanol-water mixed solvent is 9:2;

[0069] Step 3: Disperse the silicon carbide treated in Step 2 in deionized water, ultrasonically disperse for 20 minutes at 150W, add nickel nitrate, stir evenly at 300rpm, then add sodium borohydride (prepared as a 5% ice-water dispersion and sprayed in), stir continuously at 20℃ for 60 minutes, filter and collect the precipitated particles, wash three times with deionized water, and dry at 80℃ for 2 hours to obtain silicon carbide with surface-deposited active metal; wherein, the mass-volume ratio of silicon carbide treated in Step 2 to deionized water is 1g:10ml, the mass ratio of silicon carbide treated in Step 2 to nickel nitrate is 100:5, and the molar ratio of sodium borohydride to nickel ions is 2:1;

[0070] Step 4: Add an interface modifier to the silicon carbide treated in Step 3, then add deionized water or ethanol, ultrasonically disperse for 10 minutes, mix thoroughly, and dry at 80°C for 2 hours to obtain the final product. The mass ratio of the silicon carbide treated in Step 3 to the interface modifier is 1:0.1. The interface modifier is a mixture of a silane coupling agent and nano-rare earth oxides. The mass ratio of the silane coupling agent KH550 to the nano-rare earth oxide yttrium trioxide is 2:1. The mass-to-volume ratio of the silicon carbide treated in Step 3 to deionized water is 1 g:8 mL.

[0071] The preparation method of the ceramic-reinforced aluminum alloy composite material described above is the same as in Example 1.

[0072] Example 4

[0073] A ceramic-reinforced aluminum alloy composite material, wherein the interface modifier is prepared by pretreatment of a silane coupling agent and nano-rare earth oxides, and the pretreatment method is as follows:

[0074] Step a: Dissolve silane coupling agent KH550 and polyethylene glycol in anhydrous ethanol, stir at 70°C and 300 rpm for 60 min, then let stand and age for 45 min to obtain a light yellow transparent pre-assembled solution; wherein, the mass ratio of silane coupling agent KH550 to polyethylene glycol is 50:15, and the mass-volume ratio of silane coupling agent to anhydrous ethanol is 1 g:4 ml;

[0075] Step b: Disperse nano-rare earth oxide cerium dioxide in anhydrous ethanol, add aluminum zirconium coupling agent, and stir at 70℃ and 300 rpm for 1 hour to obtain a mixture. Then, add the mixture to the pre-assembled solution obtained in step a, continue stirring for 45 minutes, and then let it stand at 22℃ for 1.5 hours to obtain a pre-assembled composite. The mass ratio of nano-rare earth oxide cerium dioxide to aluminum zirconium coupling agent is 100:2, the mass ratio of the pre-assembled solution to nano-rare earth oxide cerium dioxide is 1:0.25, and the mass-volume ratio of nano-rare earth oxide cerium dioxide to ethanol is 1g:10ml.

[0076] Step c: Dissolve nano-silver and silane coupling agent KH550 in anhydrous ethanol, and ultrasonically disperse for 15 minutes at 200W and 60℃ to ensure uniform dispersion of the nano-silver and coating of its surface with the coupling agent, obtaining a dispersion. Add the pre-assembled composite obtained in step b to the dispersion, continue ultrasonic dispersion for 25 minutes, dry at 60℃ for 3 hours, remove ethanol, and obtain the pretreated composite interface modifier. The mass ratio of nano-silver to silane coupling agent KH550 is 1.2:1, and the mass-to-volume ratio of nano-silver to anhydrous ethanol is 1g:10ml.

[0077] The rest is the same as in Example 1.

[0078] Example 5

[0079] The composite modification method of the interface modifier is as follows:

[0080] Step a: Dissolve silane coupling agent KH550 and polyethylene glycol in anhydrous ethanol, stir at 80°C and 200 rpm for 80 min, then let stand and age for 30 min to obtain a light yellow transparent pre-assembled solution; wherein, the mass ratio of silane coupling agent KH550 to polyethylene glycol is 60:10, and the mass-volume ratio of silane coupling agent to anhydrous ethanol is 1 g:5 ml;

[0081] Step b: Disperse nano-rare earth oxide cerium dioxide in anhydrous ethanol, add aluminum zirconium coupling agent, and stir at 80℃ and 200 rpm for 2 hours to obtain a mixture. Then, add the mixture to the pre-assembled solution obtained in step a, continue stirring for 30 minutes, and then let it stand at 25℃ for 1 hour to obtain a pre-assembled composite. The mass ratio of nano-rare earth oxide cerium dioxide to aluminum zirconium coupling agent is 100:3, the mass ratio of the pre-assembled solution to nano-rare earth oxide cerium dioxide is 1:0.3, and the mass-volume ratio of nano-rare earth oxide cerium dioxide to ethanol is 1g:12ml.

[0082] Step c: Dissolve nano-silver and silane coupling agent KH550 in anhydrous ethanol, and ultrasonically disperse for 10 minutes at 200W and 70℃ to ensure uniform dispersion of the nano-silver and coating of its surface with the coupling agent, obtaining a dispersion. Add the pre-assembled composite obtained in step b to the dispersion, continue ultrasonic dispersion for 30 minutes, dry at 70℃ for 2 hours, remove ethanol, and obtain the pretreated composite interface modifier. The mass ratio of nano-silver to silane coupling agent KH550 is 1.3:1, and the mass-to-volume ratio of nano-silver to anhydrous ethanol is 1g:20ml.

[0083] The rest is the same as in Example 2.

[0084] Comparative Example 1

[0085] A ceramic-reinforced aluminum alloy composite material comprises the following raw materials in parts by weight: 80 parts of aluminum alloy matrix, 15 parts of ceramic reinforcing phase, wherein the ceramic reinforcing phase is silicon carbide, and the rest are the same as in Example 1.

[0086] Comparative Example 2

[0087] A ceramic-reinforced aluminum alloy composite material, wherein the method for preparing the ceramic reinforcing phase includes the following steps:

[0088] Step 1: Place silicon carbide and silane coupling agent KH550 in a container, add anhydrous ethanol, and ultrasonically disperse at 300W power and 35kHz frequency for 30 minutes, controlling the temperature at 60℃, so that the coupling agent uniformly coats the particle surface. After ultrasonication, dry the mixture at 70℃ for 4 hours to remove the ethanol, obtaining silicon carbide with coupling agent attached to the surface; wherein, the mass ratio of silicon carbide to silane coupling agent KH550 is 100:1, and the mass-volume ratio of silicon carbide to anhydrous ethanol is 100g:800ml;

[0089] Step 2: Dissolve tetraethyl orthosilicate in an ethanol-water mixed solvent, stir at 300 rpm until homogeneous, adjust the pH of the solution to 3-4 with 1 mol / L dilute nitric acid, add the silicon carbide treated in Step 1, stir in a 70°C water bath for 3 hours to form a homogeneous sol, dry the sol at 100°C for 18 hours to transform it into a gel, place the gel in a muffle furnace, calcine at 500°C for 2 hours to remove organic matter and form a nano-scale silica coating layer; wherein, the mass ratio of silicon carbide treated in Step 1 to tetraethyl orthosilicate (TEOS) is 100:8, the mass-volume ratio of tetraethyl orthosilicate to the ethanol-water mixed solvent is 8 g:100 ml, and the volume ratio of ethanol to water in the ethanol-water mixed solvent is 9:1.5;

[0090] Step 3: Disperse the silicon carbide treated in Step 2 in deionized water, ultrasonically disperse for 15 minutes at 200W, add nickel nitrate, and stir evenly at 250rpm. Then add sodium borohydride (prepared as a 5% ice-water dispersion and sprayed in), and continue stirring at 23°C for 45 minutes. Filter and collect the precipitated particles, wash three times with deionized water, and dry at 70°C for 3 hours to obtain silicon carbide with surface-deposited active metal. The mass-to-volume ratio of silicon carbide treated in Step 2 to deionized water is 1g:15ml, the mass ratio of silicon carbide treated in Step 2 to nickel nitrate is 100:8, and the molar ratio of sodium borohydride to nickel ions is 1.8:1. The rest is the same as in Example 1.

[0091] Comparative Example 3

[0092] A ceramic-reinforced aluminum alloy composite material comprises the following raw materials in parts by weight: 75 parts of aluminum alloy matrix and 20 parts of ceramic reinforcing phase;

[0093] The method for preparing the ceramic reinforcing phase includes the following steps:

[0094] Step 1: Place silicon carbide and silane coupling agent KH550 in a container, add anhydrous ethanol, and ultrasonically disperse at 200W power and 40kHz frequency for 20 minutes, controlling the temperature at 50℃, so that the coupling agent uniformly coats the particle surface. After ultrasonication, dry the mixture at 80℃ for 3 hours to remove the ethanol, obtaining silicon carbide with coupling agent attached to the surface; wherein, the mass ratio of silicon carbide to silane coupling agent KH550 is 100:0.5, and the mass-volume ratio of silicon carbide to anhydrous ethanol is 100g:1000ml;

[0095] Step 2: Dissolve tetraethyl orthosilicate in an ethanol-water mixed solvent, stir at 400 rpm until homogeneous, adjust the pH of the solution to 3-4 with 1 mol / L dilute nitric acid, add the silicon carbide treated in Step 1, stir in a water bath at 60°C for 4 hours to form a homogeneous sol, dry the sol at 80°C for 24 hours to transform it into a gel, place the gel in a muffle furnace, calcine at 400°C for 3 hours to remove organic matter and form a nano-scale silica coating layer; wherein, the mass ratio of silicon carbide treated in Step 1 to tetraethyl orthosilicate (TEOS) is 100:10, the mass-volume ratio of tetraethyl orthosilicate to the ethanol-water mixed solvent is 10 g:120 ml, and the volume ratio of ethanol to water in the ethanol-water mixed solvent is 9:1;

[0096] Step 3: Disperse the silicon carbide treated in Step 2 in deionized water, ultrasonically disperse for 10 minutes at 250W, add nickel nitrate, and stir evenly at 200rpm. Then add sodium borohydride (prepared as a 5% ice-water dispersion and sprayed in), and continue stirring at 25°C for 30 minutes. Filter and collect the precipitated particles, wash three times with deionized water, and dry at 60°C for 4 hours to obtain silicon carbide with surface-deposited active metal. The mass-to-volume ratio of silicon carbide treated in Step 2 to deionized water is 1g:20ml, the mass ratio of silicon carbide treated in Step 2 to nickel nitrate is 100:10, and the molar ratio of sodium borohydride to nickel ions is 1.5:1. The rest is the same as in Example 2.

[0097] Performance testing:

[0098] Tensile testing: The tensile strength, yield strength, and elongation after fracture of the composite materials obtained in the examples and comparative examples were tested according to GB / T 228.1-2021 "Metallic materials, tensile testing—Part 1: Test method at room temperature". The hardness of the composite materials obtained in the examples and comparative examples was tested according to GB / T 4340.1-2024 "Metallic materials, Vickers hardness testing—Part 1: Test method".

[0099] Table 1. Test Results

[0100] From Table 1, Figure 1 , Figure 2 As can be seen, Example 4 exhibits the best overall performance, with the highest tensile strength (398 MPa), yield strength (335 MPa), and Vickers hardness (155 HV) among all samples, while maintaining a good elongation after fracture of 9.5%. This signifies the successful preparation of an aluminum alloy composite material with high strength, high hardness, and good plasticity through optimized interface modifiers.

[0101] Comparing Examples 1-3, which used a simple mixture of interface modifiers, with Examples 4-5, which used a composite pretreatment interface agent, the performance improvement of the latter is clearly visible. At similar reinforcing phase contents, Example 4 (tensile strength 398 MPa) outperformed Example 1 (360 MPa) across the board; similarly, Example 5 (388 MPa) also outperformed Example 2 (380 MPa). This result demonstrates that the composite pretreatment process containing polyethylene glycol, aluminum-zirconium coupling agent, and nano-silver can construct a stronger and more stable interface layer, thereby more efficiently transferring the load from the aluminum matrix to the ceramic reinforcing phase and maximizing the reinforcing effect.

[0102] Comparative Example 1 (untreated silicon carbide) exhibited the worst performance due to extremely poor interfacial bonding. While Comparative Examples 2 and 3 (lacking a final interfacial modifier) ​​performed better than Comparative Example 1, they were significantly inferior to the corresponding fully treated examples. This indicates that even with silica coating and Ni deposition, the interfacial bonding strength is not optimal without the optimization of a final interfacial modifier, thus failing to fully realize the role of the reinforcing phase.

[0103] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, 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 process, method, article, or apparatus.

[0104] Although embodiments of this application have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A ceramic-reinforced aluminum alloy composite material, characterized in that, The following ingredients are included by weight: 75-85 parts aluminum alloy matrix, 10-20 parts ceramic reinforcing phase; The method for preparing the ceramic reinforcing phase includes the following steps: Step 1: Place silicon carbide and silane coupling agent in a container, add anhydrous ethanol, and ultrasonically disperse at a power of 200-400W, a frequency of 30-40kHz, for 20-40 minutes, with the temperature controlled at 50-70℃. After ultrasonication, dry the mixture at 60-80℃ for 3-5 hours to remove the ethanol and obtain silicon carbide with coupling agent attached to its surface. Step 2: Dissolve tetraethyl orthosilicate in an ethanol-water mixture and stir at 200-400 rpm until homogeneous. Adjust the pH of the solution to 3-4 with dilute nitric acid, add the silicon carbide treated in Step 1, and stir in a water bath at 60-80℃ for 2-4 hours to form a homogeneous sol. Dry the sol at 80-120℃ for 12-24 hours to convert it into a gel. Calcinate the gel at 400-600℃ for 1-3 hours to form a nano-silica coating layer. Step 3: Disperse the silicon carbide treated in step 2 in deionized water, add nickel nitrate, stir evenly at 200-300 rpm, then add sodium borohydride as a reducing agent, stir continuously at 20-25℃ for 30-60 minutes, filter to collect precipitated particles, wash with deionized water, and dry at 60-80℃ for 2-4 hours to obtain silicon carbide with surface-deposited active metal. Step 4: Add an interface modifier to the silicon carbide treated in step 3, then add deionized water or ethanol, ultrasonically disperse and mix evenly, and dry at 60-80℃ for 2-4 hours to obtain the final product.

2. The ceramic-reinforced aluminum alloy composite material according to claim 1, characterized in that, In step 1, the mass ratio of silicon carbide to silane coupling agent is 100:0.5-1.5, and the mass-volume ratio of silicon carbide to anhydrous ethanol is 100g:500-1000ml.

3. The ceramic-reinforced aluminum alloy composite material according to claim 1, characterized in that, In step 2, the mass ratio of silicon carbide and tetraethyl orthosilicate treated in step 1 is 100:5-10, and the mass-volume ratio of tetraethyl orthosilicate to ethanol-water mixed solvent is 5-10g:80-120ml, wherein the volume ratio of ethanol to water in the ethanol-water mixed solvent is 9:1-2.

4. The ceramic-reinforced aluminum alloy composite material according to claim 1, characterized in that, In step 3, the mass-to-volume ratio of silicon carbide treated in step 2 to deionized water is 1g:10-20ml, the mass ratio of silicon carbide treated in step 2 to nickel nitrate is 100:5-10, and the molar ratio of the reducing agent to nickel ions is 1.5-2:

1.

5. The ceramic-reinforced aluminum alloy composite material according to claim 1, characterized in that, In step 4, the mass ratio of silicon carbide treated in step 3 to the interface modifier is 1: 0.05-0.1, wherein the interface modifier includes silane coupling agent and nano rare earth oxide, and the mass-volume ratio of silicon carbide treated in step 3 to deionized water or ethanol is 1g:8-12mL.

6. The ceramic-reinforced aluminum alloy composite material according to claim 5, characterized in that, The interface modifier is a mixture of silane coupling agent and nano-rare earth oxide in a mass ratio of 0.5-2:0.2-1, wherein the silane coupling agent is KH550 and the nano-rare earth oxide is nano-yttrium trioxide or cerium dioxide.

7. The ceramic-reinforced aluminum alloy composite material according to claim 5, characterized in that, The interface modifier is prepared by modifying and pretreating a silane coupling agent and nano-rare earth oxides. The modification and pretreating method is as follows: Step a: Dissolve the silane coupling agent and polyethylene glycol in anhydrous ethanol, stir at 60-80℃ and 200-400 rpm for 40-80 minutes, and then let it stand for 30-60 minutes to obtain a light yellow transparent pre-assembled liquid. Step b: Disperse the nano-rare earth oxides in anhydrous ethanol, add aluminum zirconium coupling agent, and stir at 60-80℃ and 200-400rpm for 1-2 hours to obtain a mixture. Then, add the mixture to the pre-assembled liquid obtained in step a, continue stirring for 30-60 minutes, and then let it stand at 20-25℃ for 1-2 hours to obtain the pre-assembled composite. Step c: Dissolve nano-silver and silane coupling agent in anhydrous ethanol, and ultrasonically disperse at 50-70℃ for 10-20 minutes to obtain a dispersion. Add the pre-assembled composite obtained in step b to the dispersion, continue ultrasonic dispersion for 20-30 minutes, dry at 50-70℃ for 2-4 hours, remove ethanol, and obtain the pretreated composite interface modifier.

8. The ceramic-reinforced aluminum alloy composite material according to claim 7, characterized in that, In step a, the mass ratio of the silane coupling agent to polyethylene glycol is 40-60:10-20, and the mass-volume ratio of the silane coupling agent to anhydrous ethanol is 1g:3-5ml.

9. The ceramic-reinforced aluminum alloy composite material according to claim 7, characterized in that, In step b, the mass ratio of nano-rare earth oxide to aluminum zirconium coupling agent is 100:1-3, the mass ratio of the pre-assembled liquid to nano-rare earth oxide is 1:0.2-0.3, the mass-volume ratio of nano-rare earth oxide to ethanol is 1g:8-12ml, and the nano-rare earth oxide is nano-yttrium trioxide or cerium dioxide. In step c, the mass ratio of the nano-silver to the silane coupling agent is 1-1.3:1, and the mass-volume ratio of the nano-silver to anhydrous ethanol is 1g:10-20ml.

10. The method for preparing ceramic-reinforced aluminum alloy composite materials as described in claims 1-9, characterized in that, Includes the following steps: Step A: Melt the aluminum alloy matrix at 700-750℃ and hold for 10-30 minutes, then pass argon or nitrogen gas through it for degassing and refining for 10-20 minutes, and finally let it stand for 5-15 minutes to remove slag. Step B: Heat the aluminum alloy melt to 720-760℃, add the ceramic reinforcing phase in 2-3 batches, with an interval of 3-5 minutes between each addition, while stirring at 300-500 rpm. After each addition, stir for 15-20 minutes to obtain the composite melt. Step C: Pour the composite melt into a metal mold preheated to 200-250℃, cool to room temperature and demold, then solution treat at 500-550℃ for 1-2 hours, water quench, then hold at 175-185℃ for 4-8 hours, and air cool to obtain the final product.

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