Ceramic particle reinforced aluminum-based composite material and preparation method thereof

Abstract

The invention relates to the field of aluminum-based composite materials, and particularly discloses a ceramic particle reinforced aluminum-based composite material and a preparation method thereof.The composite material is composed of an aluminum matrix and surface modified silicon carbide particles, and the surfaces of the surface modified silicon carbide particles are coated with silicon dioxide barrier layers through a sol-gel method; the preparation method comprises the following steps: preheating modified ceramic particles, depositing a nickel-phosphorus alloy infiltration layer through a chemical plating method, adding the preheated modified ceramic particles into an aluminum melt, carrying out electromagnetic stirring for preliminary dispersion, cooling the melt to a semi-solid interval, carrying out mechanical stirring and ultrasonic vibration at the same time to realize uniform dispersion of the particles, and finally carrying out pouring, solid solution and aging treatment to obtain a finished product. In the prepared aluminum-based composite material, the wettability of the surface modified silicon carbide and the aluminum melt is good, and the fatigue strength of the composite material is high.

Description

Technical Field

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

[0002] Aluminum-based composites, especially ceramic particle-reinforced aluminum-based composites, have shown great potential in aerospace, automotive, and electronic packaging fields due to their high specific strength and good thermal conductivity. Hao Bin et al. discovered that the ceramic particle reinforcing phase entering the aluminum alloy matrix can refine the grain and improve the overall performance of the aluminum alloy material. However, its performance advantages have always faced two core problems in the industrialization process. First, in terms of the interface, commonly used reinforcements such as silicon carbide have poor wettability with aluminum melt, and are prone to harmful interfacial reactions during high-temperature preparation, generating brittle and hygroscopic Al4C3 phase. This phase not only weakens the interfacial bonding strength and becomes a source of microcrack initiation, but also deteriorates the corrosion resistance of the material, becoming a safety hazard for long-term service. Secondly, in terms of dispersibility, ceramic particles are prone to macroscopic segregation and microscopic agglomeration in the melt due to density differences and van der Waals forces. Although traditional mechanical stirring can achieve preliminary mixing, it is difficult to break up the firm micron-sized agglomerates, resulting in flow blind zones. As stress concentration points, particle agglomerates reduce the effective load-bearing area of ​​the material and become the preferred initiation sites for fatigue cracks, leading to lower-than-expected fatigue strength of the composite material.

[0003] The prior art discloses a nano-ceramic particle-reinforced aluminum matrix composite material and its preparation method, including the following steps: Step 1: Nano-ceramic particles are uniformly mixed with aluminum or aluminum alloy powder by high-energy mechanical ball milling; Step 2: The mixed powder obtained in Step 1 is sintered to obtain the desired composite material; The composite material of the present invention has high-density stacking faults / microtwins, which enables the aluminum matrix material to maintain good microstructure thermal stability and effectively hinder dislocation movement at high temperatures, so that the aluminum matrix material still maintains high strength even above 400℃, which can effectively break through the bottleneck of the current aluminum matrix material high-temperature strength decreasing sharply above 200℃.

[0004] Existing technology discloses an in-situ nano-TiC ceramic particle-reinforced aluminum matrix composite material and its preparation method. The in-situ nano-TiC ceramic particle-reinforced aluminum or aluminum alloy matrix composite material is prepared using a combustion synthesis chemical reaction method and hot pressing technology. The size of the in-situ synthesized TiC ceramic particles is less than 100 nanometers, and the weight percentage content is 3-30%. The preparation method is as follows: 1) Mixing reactant powders in a certain proportion to form a preform; 2) Mixing evenly in a drum ball mill and a mortar; 3) Pressing into a reaction preform at room temperature; 4) Placing the graphite mold containing the preform into a vacuum / atmosphere protected combustion furnace with a hydraulic device to initiate the combustion reaction. Once the combustion reaction occurs, an axial pressure of 40±5 MPa is immediately applied to the preform, held for 30-40 seconds, and then cooled to room temperature with the furnace, thus synthesizing the nano-TiC ceramic particle-reinforced pure aluminum or aluminum alloy matrix composite material.

[0005] In summary, current inventions of ceramic particle-reinforced aluminum matrix composites mainly focus on improving strength, while the corrosion resistance and fatigue strength of the composites are rarely mentioned. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a ceramic particle-reinforced aluminum matrix composite material and its preparation method. The composite material consists of an aluminum matrix and surface-modified silicon carbide particles. The surface of the silicon carbide particles is coated with a silicon dioxide barrier layer by a sol-gel method, and then a nickel-phosphorus alloy wetting layer is deposited by a chemical plating method. During preparation, the preheated modified particles are first added to the aluminum melt and initially dispersed by electromagnetic stirring. Then, the melt is cooled to the semi-solid range, and ultrasonic vibration is applied while mechanical stirring to achieve uniform dispersion of the particles. Finally, the finished product is obtained through casting, solution treatment, and aging treatment.

[0007] Specifically, it is a ceramic particle reinforced aluminum matrix composite material, comprising the following components in parts by weight: 88-96 parts of aluminum matrix and 4-12 parts of surface-modified ceramic particles;

[0008] The aluminum matrix comprises the following elements by mass percentage: silicon: 0.2%~1.0%, magnesium: 0.3%~1.5%, total unavoidable impurities: ≤0.15%, and the balance being aluminum;

[0009] This aluminum matrix controls silicon content to 0.2%–1.0% to avoid the formation of coarse and brittle silicon phases, thus preserving the matrix's high plasticity and toughness. Magnesium content is 0.3%–1.5%, forming the Mg2Si phase with silicon. Subsequent solution aging treatment produces a precipitation strengthening effect, providing the material with high strength. The aluminum matrix not only provides an efficient load transfer platform for the particles but also better coordinates interfacial thermal stress, thus jointly endowing the composite material with a perfect combination of excellent tensile strength, fatigue performance, and good plasticity.

[0010] The surface-modified ceramic particles are silicon carbide particles with an average particle size of 5~20μm.

[0011] The surface-modified ceramic particles are ceramic particles that are sequentially coated with a nickel-phosphorus alloy wetting layer and a silicon dioxide barrier layer from the outside to the inside.

[0012] Preferably, the preparation process of the surface-modified ceramic particles includes the following steps:

[0013] Step 1: Coat the surface of ceramic particles with a silica barrier layer using the sol-gel method;

[0014] Step 1.1: After preparing tetraethyl orthosilicate and ethanol in a volume ratio of 1:3 to 1:5, add deionized water in a molar ratio of 7:1 to 9:1 with tetraethyl orthosilicate, and then add hydrochloric acid with a concentration of 0.1 to 0.3 mol / L to adjust the pH of the mixed solution to 3.0 to 5.0 to obtain a sol;

[0015] Step 1.2: Add 100~500g of ceramic particles to 1000~5000mL of the sol obtained in Step 1.1. Place the mixture in a constant temperature water bath at 60~80℃ and continuously stir mechanically at a speed of 500~800r / min for 4~6h. After the reaction is completed, remove the particles by centrifugation and let the particles stand at room temperature for 12~16h. Then transfer the particles to a drying oven at 60~80℃ and dry for 16~24h.

[0016] Step 1.3: Place the particles obtained in Step 1.2 in a muffle furnace and heat them to 500-700°C at a heating rate of 5-8°C / min in an air atmosphere. Hold them at this temperature for 2-4 hours and cool them with the furnace to obtain ceramic particles coated with a silica barrier layer.

[0017] Step 2: Deposit a nickel-phosphorus alloy wetting layer on the silicon dioxide barrier layer using a chemical plating method;

[0018] Step 2.1: The particles with the silica barrier layer obtained in Step 1.3 are placed in anhydrous ethanol and ultrasonically cleaned at room temperature for 5-10 min. Then, they are washed with anhydrous ethanol and air-dried. The cleaned particles are then immersed in a sensitization solution for sensitization treatment. The sensitization solution contains 5-15 g / L stannous chloride and 0.36-0.60 mol / L hydrochloric acid. The sensitization treatment temperature is 30-50℃ and the sensitization treatment time is 10-30 min.

[0019] Step 2.2: Wash the particles obtained in Step 2.1 with deionized water, then immerse them in an activation solution for activation treatment and wash them with deionized water. The activation solution contains: 2~5 g / L silver nitrate, 0.15~0.40 mol / L ammonia water, and a pH value of 9.0~10.5. The activation treatment is carried out under gentle stirring at a stirring rate of 100~300 r / min.

[0020] Step 2.3: Place the particles obtained in Step 2.2 into a chemical plating solution for plating. The chemical plating solution is prepared as follows: under continuous stirring with a glass rod, dissolve 15-25 mL of lactic acid, 5-15 g of sodium citrate, and 10-20 g of sodium acetate in 1-2 L of deionized water, then add 20-35 g of nickel sulfate until it is completely dissolved, then add 20-35 g of sodium hypophosphite until it is dissolved, and finally add 0.5-1.5 g of potassium iodide to obtain the chemical plating solution. Adjust the pH of the chemical plating solution to 4.8-5.2, and plating at a temperature of 80-90℃ for 20-40 min. During the plating process, mechanical stirring is performed at a speed of 300-500 r / min.

[0021] Step 2.4: After the reaction is complete, filter out the particles, wash them repeatedly with deionized water and ethanol, and finally dry them in a vacuum drying oven at 60~100℃ for 1~3 hours to obtain surface-modified ceramic particles.

[0022] In the preparation of ceramic particle-reinforced aluminum matrix composites, sensitization and activation treatments are key steps in constructing chemical plating catalytic centers on the surface of non-metallic ceramic particles. The core objective is to form uniformly dispersed active sites on the particle surface through a two-step reaction, ensuring that the subsequent nickel-phosphorus alloy wetting layer can be firmly deposited and play a role in improving wettability, thereby solving the technical problem of poor interfacial compatibility between ceramic particles and aluminum melt. The core function of sensitization is to adsorb a reducing substance onto the surface of ceramic particles, providing a foundation for the subsequent activation reaction. Stannous chloride, as the core component of the sensitization solution, provides low-valence metal ions capable of reducing noble metal ions. Hydrochloric acid maintains the acidic environment of the solution, inhibiting the hydrolysis of stannous chloride to generate inactive hydroxides, preventing the sensitization solution from failing, and ensuring the reducing substance is stably adsorbed onto the particle surface. Activation involves bringing the particle surface, now adsorbed with the reducing substance, into contact with the activation solution. This allows the noble metal ions in the activation solution to be reduced to catalytically active metal particles. These particles act as crystallization centers for electroless plating, initiating the deposition process of the nickel-phosphorus alloy. Silver nitrate in the activation solution provides catalytically active noble metal ions, while ammonia adjusts the pH of the solution to form a stable complexing system, preventing premature precipitation of silver ions and ensuring that the noble metal ions are evenly distributed and fully reduced. During the preparation process, careful control of the sensitization and activation conditions, as well as the cleaning steps, is crucial. Insufficient processing time leads to inadequate adsorption of reducing substances during sensitization and insufficient generation of catalytic nuclei during activation, resulting in incomplete coating coverage or weak adhesion. Excessive processing time causes excessive aggregation of reducing substances or catalytic nuclei, resulting in a rough and porous coating. Over-cleaning removes the reducing substances or catalytic nuclei adsorbed on the particle surface, while incomplete cleaning allows residual sensitization solution to contaminate the activation solution, and residual activation solution to be introduced into subsequent chemical plating solutions, causing decomposition of the plating solution, all of which disrupt the continuity of the process. Simultaneously, it is essential to ensure the composition and... The coordination of the process is crucial. If the concentration of stannous chloride in the sensitizing solution deviates from the reasonable range, it will lead to insufficient or excessive reduction capacity. Insufficient hydrochloric acid concentration will cause stannous chloride hydrolysis. Excessive concentration may corrode the particle surface or interfere with the stability of the activation solution. Excessive concentration of silver nitrate in the activation solution will cause catalytic crystal nuclei to agglomerate, while insufficient concentration will result in insufficient catalytic sites. Improper use of ammonia water will lead to silver ion precipitation or imbalance of the reduction reaction. All of these will lead to uneven distribution of catalytic centers, ultimately affecting the uniformity and bonding strength of the nickel-phosphorus alloy coating, and failing to achieve the core goal of improving the wettability of ceramic particles and aluminum melt and inhibiting harmful interfacial reactions.

[0023] Preferably, the weight gain percentage of the silica barrier layer coating the surface of the surface-modified ceramic particles is 0.2% to 1.5%, the weight gain percentage of the nickel-phosphorus alloy wetting layer is 2% to 6%, and the phosphorus content of the nickel-phosphorus alloy wetting layer is 6% to 10% of the mass.

[0024] This invention resolves the contradictions in the preparation of ceramic particle-reinforced aluminum matrix composites through interface design and component control. Using silicon carbide as the reinforcement, its high hardness and high modulus provide a strong foundation for the aluminum matrix. The dual-layer structure of a silica barrier layer and a nickel-phosphorus alloy wetting layer improves interfacial compatibility: the inner silica layer acts as a chemical barrier, suppressing harmful interfacial reactions between the molten aluminum and silicon carbide particles during high-temperature preparation, thus preventing the formation of brittle phases; the outer nickel-phosphorus alloy layer acts as a metallurgical transition layer, achieving uniform particle dispersion through good wettability with the molten aluminum. Simultaneously, silicon in the aluminum matrix regulates melt flowability and inhibits interfacial reactions, while magnesium further improves the wettability of the melt on the ceramic particles, laying a solid foundation for obtaining a composite material with good interfacial bonding, uniform microstructure, and excellent overall performance.

[0025] This invention further discloses a method for preparing the above-mentioned ceramic particle-reinforced aluminum matrix composite material, comprising the following steps:

[0026] Step S1: Melt the aluminum matrix raw material at 720~760℃ to form an aluminum matrix melt;

[0027] Step S2: Preheat the surface-modified ceramic particles at 400~600℃ for 1~3h, then add them to the aluminum-based melt obtained in step S1, and perform preliminary dispersion under electromagnetic stirring to obtain a pre-dispersed melt.

[0028] Step S3: Cool the pre-dispersed melt obtained in step S2 to the semi-solid range, and apply ultrasonic vibration treatment while mechanically stirring. The ultrasonic power is 1~4kW, the frequency is 20~30kHz, and the treatment time is 10~30min to obtain a uniform composite material melt.

[0029] Step S4: The uniform composite material melt obtained in step S3 is poured into a metal mold preheated to 200~350℃, and after cooling, an ingot is obtained. The ingot is subjected to solution treatment and aging treatment to obtain ceramic particle reinforced aluminum matrix composite material.

[0030] Preferably, in step S2, the electromagnetic stirring intensity is 400~500mT and the stirring time is 10~30min.

[0031] Preferably, in step S3, the temperature of the semi-solid region is 610~640℃.

[0032] As a preferred option, in step S4, the solution treatment process is as follows: first, heat treatment at 500~530℃ for 1~2 hours, followed by water quenching; the aging treatment process is as follows: heat treatment at 150~180℃ for 4~16 hours.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] This invention, through the synergistic effect of double coating, suppresses harmful interfacial reactions and achieves high-strength, stable interfacial bonding. The inner silica barrier layer isolates the aluminum melt from contact with silicon carbide particles, thereby preventing the formation of brittle Al4C3 phase. However, the wettability of silica and aluminum is not ideal. Therefore, the outer nickel-phosphorus alloy wetting layer plays a role. This metal layer can wet the aluminum melt well and react to form a strong metallurgical bond. The two layers complement each other. This synergistic design of barrier and wetting overcomes the limitations of a single coating, ensuring a clean interface while achieving high-strength interfacial bonding, thereby improving the mechanical properties and long-term stability of the composite material. Detailed Implementation

[0035] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. 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.

[0036] Example 1

[0037] A ceramic particle-reinforced aluminum matrix composite material, characterized in that it comprises the following components in parts by weight: 90 parts aluminum matrix and 10 parts surface-modified ceramic particles; the aluminum matrix comprises the following elements in mass percentage: silicon: 0.2%~1.0%, magnesium: 0.3%~1.5%, total unavoidable impurities: ≤0.15%, and the balance being aluminum; the surface-modified ceramic particles are silicon carbide particles with an average particle size of 10 μm; the surface of the surface-modified ceramic particles is coated with a silica barrier layer and a nickel-phosphorus alloy wetting layer from the inside out;

[0038] A ceramic particle-reinforced aluminum-based composite material, wherein the preparation process of the surface-modified ceramic particles includes the following steps:

[0039] Step 1: Coat the surface of ceramic particles with a silica barrier layer using the sol-gel method;

[0040] Step 1.1: After preparing tetraethyl orthosilicate and ethanol in a volume ratio of 1:4, add deionized water in a molar ratio of 8:1 to tetraethyl orthosilicate, and then add hydrochloric acid with a concentration of 0.1 mol / L to adjust the pH of the mixed solution to 4.0 to obtain a sol.

[0041] Step 1.2: Add 500g of ceramic particles to 5000mL of the sol obtained in Step 1.1. Place the mixture in an 80℃ constant temperature water bath and continuously stir mechanically at 500r / min for 4h. After the reaction is completed, remove the particles by centrifugation, let the particles stand at room temperature for 12h, and then transfer the particles to an 80℃ drying oven to dry for 24h.

[0042] Step 1.3: Place the particles obtained in Step 1.2 in a muffle furnace and heat them to 600°C at a heating rate of 5°C / min in an air atmosphere. Hold them at this temperature for 4 hours and cool them with the furnace to obtain ceramic particles coated with a silica barrier layer.

[0043] Step 2: Deposit a nickel-phosphorus alloy wetting layer on the silicon dioxide barrier layer using a chemical plating method;

[0044] Step 2.1: The particles with silica barrier layer obtained in step 1.3 are placed in anhydrous ethanol and ultrasonically cleaned at room temperature for 5 min. Then they are washed with anhydrous ethanol and air-dried. The cleaned particles are then immersed in a sensitization solution for sensitization treatment. The sensitization solution contains 10 g / L stannous chloride and 0.4 mol / L hydrochloric acid. The treatment temperature is 40℃ and the treatment time is 20 min.

[0045] Step 2.2: Wash the particles obtained in Step 2.1 with deionized water, then immerse them in an activation solution for activation treatment and wash them with deionized water. The activation solution contains: 2 g / L silver nitrate, 0.2 mol / L ammonia water, and pH 9.5. The activation treatment is carried out under gentle stirring at a stirring rate of 100 r / min.

[0046] Step 2.3: Place the particles obtained in Step 2.2 into a chemical plating solution for plating. The chemical plating solution is prepared as follows: under continuous stirring with a glass rod, dissolve 20 mL of lactic acid, 10 g of sodium citrate, and 10 g of sodium acetate in 1 L of deionized water in sequence. Then add 20 g of nickel sulfate until it is completely dissolved, then add 20 g of sodium hypophosphite until it is dissolved, and finally add 0.5 g of potassium iodide to adjust the pH value to 5.0. Plating is carried out at a temperature of 90°C for 30 min. During the plating process, mechanical stirring is performed at a speed of 300 r / min.

[0047] Step 2.4: After the reaction is complete, filter out the particles, wash them repeatedly with deionized water and ethanol, and finally dry them in a vacuum drying oven at 60°C for 1 hour to obtain surface-modified ceramic particles.

[0048] The weight gain percentage of the silica barrier layer coated on the surface of the surface-modified ceramic particles is 0.9%, the weight gain percentage of the nickel-phosphorus alloy wetting layer is 4%, and phosphorus accounts for 6% of the mass percentage of the nickel-phosphorus alloy wetting layer.

[0049] A method for preparing a ceramic particle-reinforced aluminum matrix composite material includes the following steps:

[0050] S1: Melt the aluminum matrix raw material at 720℃ to form an aluminum matrix melt;

[0051] S2: The surface-modified ceramic particles are preheated at 400℃ for 2 hours, and then added to the aluminum-based melt obtained in step S1. The particles are initially dispersed under electromagnetic stirring conditions. The electromagnetic stirring intensity is 400mT and the stirring time is 30min to obtain a pre-dispersed melt.

[0052] S3: Cool the pre-dispersed melt obtained in step S2 to the semi-solid range at a temperature of 640°C, and apply ultrasonic vibration treatment while mechanically stirring. The ultrasonic power is 2kW, the frequency is 20kHz, and the treatment time is 20min to obtain a uniform composite material melt.

[0053] S4: The uniform composite material melt obtained in step S3 is poured into a metal mold preheated to 300°C. After cooling, an ingot is obtained. The ingot is subjected to solution treatment and aging treatment. The solution treatment process is to first hold at 500°C for 1 hour and then water quench. The aging treatment process is to hold at 150°C for 8 hours to obtain ceramic particle reinforced aluminum matrix composite material.

[0054] Example 2

[0055] A ceramic particle-reinforced aluminum matrix composite material, characterized in that it comprises the following components in parts by weight: 88 parts aluminum matrix and 4 parts surface-modified ceramic particles; the aluminum matrix comprises the following elements in weight percentage: silicon: 0.2%~1.0%, magnesium: 0.3%~1.5%, total unavoidable impurities: ≤0.15%, and the balance being aluminum; the surface-modified ceramic particles are silicon carbide particles with an average particle size of 10 μm; the surface of the surface-modified ceramic particles is coated with a silica barrier layer and a nickel-phosphorus alloy wetting layer from the inside out;

[0056] A ceramic particle-reinforced aluminum-based composite material, wherein the preparation process of the surface-modified ceramic particles includes the following steps:

[0057] Step 1: Coat the surface of ceramic particles with a silica barrier layer using the sol-gel method;

[0058] Step 1.1: After preparing tetraethyl orthosilicate and ethanol in a volume ratio of 1:4, add deionized water in a molar ratio of 8:1 to tetraethyl orthosilicate, and then add hydrochloric acid with a concentration of 0.1 mol / L to adjust the pH of the mixed solution to 4.0 to obtain a sol.

[0059] Step 1.2: Add 500g of ceramic particles to 5000mL of the sol obtained in Step 1.1. Place the mixture in an 80℃ constant temperature water bath and continuously stir mechanically at 500r / min for 4h. After the reaction is completed, remove the particles by centrifugation, let the particles stand at room temperature for 12h, and then transfer the particles to an 80℃ drying oven to dry for 24h.

[0060] Step 1.3: Place the particles obtained in Step 1.2 in a muffle furnace and heat them to 600°C at a heating rate of 5°C / min in an air atmosphere. Hold them at this temperature for 4 hours and cool them with the furnace to obtain ceramic particles coated with a silica barrier layer.

[0061] Step 2: Deposit a nickel-phosphorus alloy wetting layer on the silicon dioxide barrier layer using a chemical plating method;

[0062] Step 2.1: The particles with silica barrier layer obtained in step 1.3 are placed in anhydrous ethanol and ultrasonically cleaned at room temperature for 5 min. Then they are washed with anhydrous ethanol and air-dried. The cleaned particles are then immersed in a sensitization solution for sensitization treatment. The sensitization solution contains 10 g / L stannous chloride and 0.4 mol / L hydrochloric acid. The treatment temperature is 40℃ and the treatment time is 20 min.

[0063] Step 2.2: Wash the particles obtained in Step 2.1 with deionized water, then immerse them in an activation solution for activation treatment and wash them with deionized water. The activation solution contains: 2 g / L silver nitrate, 0.2 mol / L ammonia water, and pH 9.5. The activation treatment is carried out under gentle stirring at a stirring rate of 100 r / min.

[0064] Step 2.3: Place the particles obtained in Step 2.2 into a chemical plating solution for plating. The chemical plating solution is prepared as follows: under continuous stirring with a glass rod, dissolve 20 mL of lactic acid, 10 g of sodium citrate, and 10 g of sodium acetate in 1 L of deionized water, then add 20 g of nickel sulfate until it is completely dissolved, then add 20 g of sodium hypophosphite until it is dissolved, and finally add 0.5 g of potassium iodide to adjust the pH value to 5.0. Plating is carried out at 90°C for 30 min. During the plating process, mechanical stirring is performed at a speed of 300 r / min.

[0065] Step 2.4: After the reaction is complete, filter out the particles, wash them repeatedly with deionized water and ethanol, and finally dry them in a vacuum drying oven at 60°C for 1 hour to obtain surface-modified ceramic particles.

[0066] The weight gain percentage of the silica barrier layer coating the surface of the surface-modified ceramic particles is 0.6%, the weight gain percentage of the nickel-phosphorus alloy wetting layer is 3%, and phosphorus accounts for 6.5% of the mass percentage of the nickel-phosphorus alloy wetting layer.

[0067] A method for preparing a ceramic particle-reinforced aluminum matrix composite material includes the following steps:

[0068] S1: Melt the aluminum matrix raw material at 720℃ to form an aluminum matrix melt;

[0069] S2: The surface-modified ceramic particles are preheated at 400℃ for 2 hours, and then added to the aluminum-based melt obtained in step S1. The particles are initially dispersed under electromagnetic stirring conditions. The electromagnetic stirring intensity is 400mT and the stirring time is 30min to obtain a pre-dispersed melt.

[0070] S3: Cool the pre-dispersed melt obtained in step S2 to the semi-solid range at a temperature of 640°C, and apply ultrasonic vibration treatment while mechanically stirring. The ultrasonic power is 2kW, the frequency is 20kHz, and the treatment time is 20min to obtain a uniform composite material melt.

[0071] S4: The uniform composite material melt obtained in step S3 is poured into a metal mold preheated to 300°C. After cooling, an ingot is obtained. The ingot is subjected to solution treatment and aging treatment. The solution treatment process is to first hold at 500°C for 1 hour and then water quench. The aging treatment process is to hold at 150°C for 8 hours to obtain ceramic particle reinforced aluminum matrix composite material.

[0072] Example 3

[0073] A ceramic particle-reinforced aluminum matrix composite material, characterized in that it comprises the following components in parts by weight: 96 parts aluminum matrix and 12 parts surface-modified ceramic particles; the aluminum matrix comprises the following elements in mass percentage: silicon: 0.2%~1.0%, magnesium: 0.3%~1.5%, total unavoidable impurities: ≤0.15%, and the balance being aluminum; the surface-modified ceramic particles are silicon carbide particles with an average particle size of 10 μm; the surface of the surface-modified ceramic particles is coated with a silica barrier layer and a nickel-phosphorus alloy wetting layer from the inside out;

[0074] A ceramic particle-reinforced aluminum-based composite material, wherein the preparation process of the surface-modified ceramic particles includes the following steps:

[0075] Step 1: Coat the surface of ceramic particles with a silica barrier layer using the sol-gel method;

[0076] Step 1.1: After preparing tetraethyl orthosilicate and ethanol in a volume ratio of 1:4, add deionized water in a molar ratio of 8:1 to tetraethyl orthosilicate, and then add hydrochloric acid with a concentration of 0.1 mol / L to adjust the pH of the mixed solution to 4.0 to obtain a sol.

[0077] Step 1.2: Add 500g of ceramic particles to 5000mL of the sol obtained in Step 1.1. Place the mixture in an 80℃ constant temperature water bath and continuously stir mechanically at 500r / min for 4h. After the reaction is completed, remove the particles by centrifugation, let the particles stand at room temperature for 12h, and then transfer the particles to an 80℃ drying oven to dry for 24h.

[0078] Step 1.3: Place the particles obtained in Step 1.2 in a muffle furnace and heat them to 600°C at a heating rate of 5°C / min in an air atmosphere. Hold them at this temperature for 4 hours and cool them with the furnace to obtain ceramic particles coated with a silica barrier layer.

[0079] Step 2: Deposit a nickel-phosphorus alloy wetting layer on the silicon dioxide barrier layer using a chemical plating method;

[0080] Step 2.1: The particles with silica barrier layer obtained in step 1.3 are placed in anhydrous ethanol and ultrasonically cleaned at room temperature for 5 min. Then they are washed with anhydrous ethanol and air-dried. The cleaned particles are then immersed in a sensitization solution for sensitization treatment. The sensitization solution contains 10 g / L stannous chloride and 0.4 mol / L hydrochloric acid. The treatment temperature is 40℃ and the treatment time is 20 min.

[0081] Step 2.2: Wash the particles obtained in Step 2.1 with deionized water, then immerse them in an activation solution for activation treatment and wash them with deionized water. The activation solution contains: 2 g / L silver nitrate, 0.2 mol / L ammonia water, and pH 9.5. The activation treatment is carried out under gentle stirring at a stirring rate of 100 r / min.

[0082] Step 2.3: Place the particles obtained in Step 2.2 into a chemical plating solution for plating. The chemical plating solution is prepared as follows: under continuous stirring with a glass rod, dissolve 20 mL of lactic acid, 10 g of sodium citrate, and 10 g of sodium acetate in 1 L of deionized water, then add 20 g of nickel sulfate until it is completely dissolved, then add 20 g of sodium hypophosphite until it is dissolved, and finally add 0.5 g of potassium iodide to adjust the pH value to 5.0. Plating is carried out at 90°C for 30 min. During the plating process, mechanical stirring is performed at a speed of 300 r / min.

[0083] Step 2.4: After the reaction is complete, filter out the particles, wash them repeatedly with deionized water and ethanol, and finally dry them in a vacuum drying oven at 60°C for 1 hour to obtain surface-modified ceramic particles.

[0084] The weight gain percentage of the silica barrier layer coating the surface of the surface-modified ceramic particles is 1.2%, the weight gain percentage of the nickel-phosphorus alloy wetting layer is 5%, and phosphorus accounts for 8% of the mass percentage of the nickel-phosphorus alloy wetting layer.

[0085] A method for preparing a ceramic particle-reinforced aluminum matrix composite material includes the following steps:

[0086] S1: Melt the aluminum matrix raw material at 720℃ to form an aluminum matrix melt;

[0087] S2: The surface-modified ceramic particles are preheated at 400℃ for 2 hours, and then added to the aluminum-based melt obtained in step S1. The particles are initially dispersed under electromagnetic stirring conditions. The electromagnetic stirring intensity is 400mT and the stirring time is 30min to obtain a pre-dispersed melt.

[0088] S3: Cool the pre-dispersed melt obtained in step S2 to the semi-solid range at a temperature of 640°C, and apply ultrasonic vibration treatment while mechanically stirring. The ultrasonic power is 2kW, the frequency is 20kHz, and the treatment time is 20min to obtain a uniform composite material melt.

[0089] S4: The uniform composite material melt obtained in step S3 is poured into a metal mold preheated to 300°C. After cooling, an ingot is obtained. The ingot is subjected to solution treatment and aging treatment. The solution treatment process is to first hold at 500°C for 1 hour and then water quench. The aging treatment process is to hold at 150°C for 8 hours to obtain ceramic particle reinforced aluminum matrix composite material.

[0090] Comparative Example 1

[0091] The only difference from Example 1 is that 80 parts of aluminum matrix and 2 parts of surface-modified ceramic particles are weighed out and set aside.

[0092] Comparative Example 2

[0093] The only difference from Example 1 is that 100 parts of aluminum matrix and 15 parts of surface-modified ceramic particles are weighed out and set aside.

[0094] Comparative Example 3

[0095] The only difference from Example 1 is that the sensitized particles are directly placed into the chemical plating solution for plating.

[0096] Comparative Example 4

[0097] The only difference from Example 1 is that the ceramic particles coated with the silicon dioxide barrier layer are directly activated and then placed in a chemical plating solution for plating.

[0098] Comparative Example 5

[0099] The only difference from Example 1 is that the ceramic particles are not modified.

[0100] Comparative Example 6

[0101] The only difference from Example 1 is that only the sol-gel method is used to coat the surface of ceramic particles with a silica barrier layer.

[0102] Comparative Example 7

[0103] The only difference from Example 1 is that only chemical plating is used to deposit a nickel-phosphorus alloy wetting layer on the surface of ceramic particles.

[0104] Comparative Example 8

[0105] The only difference from Example 1 is that after the pre-dispersed melt is cooled to the semi-solid range, only mechanical stirring is used.

[0106] Performance testing:

[0107] 1. Tensile test: in accordance with ASTM E8 / E8M-25, "Standard Test Methods for Tension Testing of Metallic Materials";

[0108] 2. Fatigue strength test: According to ASTM E466-21 "Constant Amplitude Axial Fatigue Test of Metallic Materials", the specimen is a cylindrical bar with a diameter of 6~10mm, or a bent beam with a polished surface.

[0109] 3. Salt spray corrosion rate test: according to ASTM B117-19 "Standard Practice for Operating Salt Spray (Fog) Apparatus".

[0110] The performance test results are shown in Table 1.

[0111] Table 1 Test Results of Examples and Comparative Examples

[0112] In the prior art, ceramic particles have poor wettability with aluminum melt and are prone to harmful interfacial reactions at high temperatures, generating brittle and hygroscopic phases that weaken interfacial bonding strength and deteriorate corrosion resistance. At the same time, ceramic particles are prone to segregation and agglomeration due to density differences and van der Waals forces, which are difficult to overcome with traditional stirring, resulting in insufficient fatigue strength of the material. Moreover, existing inventions mostly focus on strength improvement and pay less attention to corrosion resistance and fatigue strength. The embodiment achieves optimized overall material performance by precisely controlling the ratio of aluminum matrix to surface-modified ceramic particles, optimizing the silicon and magnesium content in the aluminum matrix, and double-coating the ceramic particles with a silica barrier layer and a nickel-phosphorus alloy wetting layer from the inside out. This is further enhanced by electromagnetic stirring in the pre-dispersion stage and mechanical stirring combined with ultrasonic vibration in the semi-solid zone. The core mechanism lies in the effective inhibition of harmful interfacial reactions by the silica barrier layer, the improvement of wettability between the particles and the aluminum melt by the nickel-phosphorus alloy wetting layer, and the avoidance of insufficient reinforcement due to too few particles or agglomeration due to too many particles. The synergistic stirring process further breaks up particle agglomerates, achieving uniform particle dispersion. The reinforcing phase formed by silicon and magnesium in the aluminum matrix further enhances the material's load-bearing capacity and coordinates interfacial thermal stress. Compared to the examples, Comparative Examples 1 and 2 deviated from the optimal ratio of aluminum matrix to ceramic particles, resulting in either insufficient reinforcing phase to fully exert the reinforcing effect or excessive particles that easily caused agglomeration, leading to a decline in performance. Comparative Example 3 lacked activation treatment, and Comparative Example 4 lacked sensitization treatment, both affecting the bonding strength between the electroless nickel-phosphorus alloy wetting layer and the surface of the ceramic particles, resulting in insufficient interfacial bonding strength and inability to effectively transfer loads. Comparative Example 5 did not modify the ceramic particles in any way, failing to inhibit harmful interfacial reactions or improve wettability, exhibiting a high proportion of brittle interfacial phases and severe particle agglomeration, resulting in poor overall performance. The worst; Comparative Example 6 only has a silica barrier layer, which can suppress the interfacial reaction to some extent, but the wettability of silica with aluminum melt is poor, resulting in poor particle dispersion and interfacial bonding; Comparative Example 7 only has a nickel-phosphorus alloy wetting layer deposited, which cannot prevent direct contact between ceramic particles and aluminum melt. At high temperatures, harmful interfacial reactions will still occur to generate brittle phases, affecting the stability and corrosion resistance of the material; Comparative Example 8 did not apply ultrasonic vibration, and mechanical stirring alone was insufficient to completely disperse the micron-sized agglomerates. The particles were unevenly dispersed, forming stress concentration points, resulting in the fatigue strength and plasticity of the material being inferior to those of the examples.

[0113] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A ceramic particle-reinforced aluminum matrix composite material, characterized in that, The components include the following parts by weight: 88-96 parts aluminum matrix and 4-12 parts surface-modified ceramic particles; The aluminum matrix comprises the following elements by mass percentage: Silicon: 0.2%~1.0%, Magnesium: 0.3%~1.5%, Total unavoidable impurities: ≤0.15%, Balance: Aluminum; The surface-modified ceramic particles are ceramic particles that are sequentially coated with a nickel-phosphorus alloy wetting layer and a silicon dioxide barrier layer from the outside to the inside.

2. The ceramic particle-reinforced aluminum matrix composite material according to claim 1, characterized in that, The weight gain percentage of the silica barrier layer is 0.2% to 1.5%, the weight gain percentage of the nickel-phosphorus alloy wetting layer is 2% to 6%, and phosphorus accounts for 6% to 10% of the mass of the nickel-phosphorus alloy wetting layer.

3. The ceramic particle-reinforced aluminum matrix composite material according to claim 1, characterized in that, The preparation process of the surface-modified ceramic particles includes the following steps: Step 1: Coat the surface of ceramic particles with a silica barrier layer using the sol-gel method; Step 1.1: After preparing tetraethyl orthosilicate and ethanol in a certain proportion, deionized water is added, followed by the addition of hydrochloric acid to adjust the pH of the mixed solution to 3.0~5.0, thus obtaining a sol; Step 1.2: Add ceramic particles to the sol obtained in Step 1.1, place the mixture in a constant temperature water bath and mechanically stir for 2-6 hours. After the reaction is complete, remove the particles by centrifugation, let the particles stand at room temperature for aging, and then dry the particles. Step 1.3: Place the particles obtained in step 1.2 in a muffle furnace, heat and hold in air atmosphere for 2-4 hours, and cool with the furnace to obtain ceramic particles coated with a silica barrier layer. Step 2: Deposit a nickel-phosphorus alloy wetting layer on the silicon dioxide barrier layer using a chemical plating method; Step 2.1: Place the ceramic particles coated with the silica barrier layer obtained in step 1.3 into anhydrous ethanol, clean them with ultrasonication, dry them, and then immerse them in a sensitization solution for sensitization treatment for 10~30 min to obtain sensitized particles. Step 2.2: After washing the sensitized particles, immerse them in the activation solution for 10-30 minutes to obtain activated particles; Step 2.3: Place the activated particles into the chemical plating solution and plate them. Adjust the pH of the plating solution to 4.8~5.2 and plate them at a temperature of 80~90℃ for 20~40 minutes. Mechanical stirring is performed during the plating process. Step 2.4: After the reaction is complete, filter out the particles, wash and dry them to obtain surface-modified ceramic particles.

4. The ceramic particle-reinforced aluminum matrix composite material according to claim 3, characterized in that, The chemical plating solution is prepared as follows: 15-25 mL of lactic acid, 5-15 g of sodium citrate, and 10-20 g of sodium acetate are dissolved sequentially in 1-2 L of deionized water. Then, 20-35 g of nickel sulfate is added until it is completely dissolved. Next, 20-35 g of sodium hypophosphite is added until it is dissolved. Finally, 0.5-1.5 g of potassium iodide is added to obtain the solution.

5. The ceramic particle-reinforced aluminum matrix composite material according to claim 3, characterized in that, The ceramic particles are silicon carbide particles with an average particle size of 5~20μm.

6. The ceramic particle-reinforced aluminum matrix composite material according to claim 3, characterized in that, The sensitization solution contains 5-15 g / L stannous chloride and 0.36-0.60 mol / L hydrochloric acid; the sensitization treatment temperature is 30-50℃, and the treatment time is 10-30 min; the activation solution contains 2-5 g / L silver nitrate, ammonia water with a molar concentration of 0.15-0.40 mol / L, and the pH value of the activation solution is 9.0-10.5, and the activation treatment is carried out at 100-300 r / min.

7. A method for preparing ceramic particle-reinforced aluminum matrix composite material according to any one of claims 1 to 6, characterized in that, Includes the following steps: Step S1: Melt the aluminum matrix raw material at 720~760℃ to form an aluminum matrix melt; Step S2: Preheat the surface-modified ceramic particles at 400~600℃ for 1~3h, then add them to the aluminum-based melt obtained in step S1, and perform preliminary dispersion under electromagnetic stirring to obtain a pre-dispersed melt. Step S3: Cool the pre-dispersed melt obtained in step S2 to the semi-solid range, and apply ultrasonic vibration treatment while mechanically stirring. The ultrasonic power is 1~4kW, the frequency is 20~30kHz, and the treatment time is 10~30min to obtain a uniform composite material melt. Step S4: The uniform composite material melt obtained in step S3 is poured into a metal mold preheated to 200~350℃, and after cooling, an ingot is obtained. The ingot is subjected to solution treatment and aging treatment to obtain ceramic particle reinforced aluminum matrix composite material.

8. The method for preparing ceramic particle-reinforced aluminum matrix composite material according to claim 7, characterized in that, In step S2, the electromagnetic stirring intensity is 400~500mT and the stirring time is 10~30min.

9. The method for preparing ceramic particle-reinforced aluminum matrix composite material according to claim 7, characterized in that, In step S3, the temperature of the semi-solid region is 610~640℃.

10. The method for preparing ceramic particle-reinforced aluminum matrix composite material according to claim 7, characterized in that, In step S4, the solution treatment process is as follows: first, heat treatment at 500~530℃ for 1~2 hours, followed by water quenching. The aging treatment process is as follows: heat treatment at 150~180℃ for 4~16 hours.

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