SiC/Cu复合材料具有良好的导热性、高强度、高硬度等优异性能，被广泛应用于电子封装、换热设备、航空航天领域（如飞行器构架）、汽车领域（如刹车片、内燃机活塞和发动机叶轮）领域等。但存在制备工艺复杂、成本高、难以获得高热导率和高强度的产品等问题，限制了其发展及应用。本文采用粉末冶金法制备了高导热、高强度、低膨胀系数的SiC/Cu复合材料，系统研究了烧结温度、压力、保温保压时间等因素对SiC/Cu复合材料力学性能和热物理性能的影响，并采用响应曲面方法对其性能进行优化，获得最佳制备工艺参数。

采用粉末冶金热压工艺制备SiC/Cu复合材料，系统研究了烧结温度、烧结压力和保温保压时间等工艺参数对试样性能的影响。研究结果表明，随着烧结温度的升高，试样的致密度、硬度、抗弯强度及导热率呈先增加后降低的趋势，当烧结温度为800 ℃时，其分别为99.1%、569 MPa、128 HRB、220.47 W/m·K；孔隙率与致密度趋势相反，当烧结温度为800 ℃时，孔隙率最小为0.9%；随着温度的升高，热膨胀系数从10.43×10^-6 /K降低至8.09×10^-6 /K。当烧结压力从20 MPa增大到60 MPa时，致密度随之增加，随后增幅不大，孔隙率随之降低，并趋于平缓；当烧结压力从20 MPa增大到60 MPa时，试样的硬度从67 HRB增加到130 HRB，热膨胀系数从9.12×10^-6 /K降低到8.09×10^-6 /K。抗弯强度和导热率随烧结压力的增加呈先增大后降低的趋势，当烧结压力为50 MPa时，达到最大值567 MPa和224.72 W/m·K。随着烧结保温保压时间的增加（2~22 min），试样的性能变化趋势较小，当烧结保温保压时间为12 min时，试样的致密度、孔隙率、硬度、抗弯强度、导热率及热膨胀系数较优，分别为98.58%、1.42%、118 HRB、569 MPa、225.13 W/m·K、8.41×10^-6 /K。综上所述，最佳烧结温度、烧结压力、烧结保温保压时间分别是：800 ℃、50 MPa、12 min。

在最佳工艺参数的基础上，研究SiC含量对试样性能的影响，并用Maxwell-Eucken模型和核-壳球体颗粒增强“复合热导率立方体”模型对试样的导热率进行了预测，用ROM混合定律和Turner模型预测了复合材料的热膨胀系数。研究结果表明：试样中生成的金属间化合物AlCuMg大大提高了材料的强度；当SiC含量为35 vol%时，SiC颗粒在基体中分散较均匀，试样的致密度、孔隙率、抗弯强度、热导率和热膨胀系数最大，分别为98.81%、1.19%、478 MPa、254.76 W/m·K和11.84×10^-6 /K。随着SiC含量的增加，SiC颗粒团聚较严重，试样的致密度、抗弯强度、热导率和热膨胀系数随之降低，孔隙率随之增加；其硬度呈先增加后降低的趋势，当SiC含量为45 vol%时，达到最大值110 HRB。发现当SiC含量较低时，核-壳球体颗粒增强“复合热导率立方体”模型预测值的导热系数与实测值相符，用Turner模型预测的热膨胀系数与实测值接近。

采用响应面法（RSM）进一步优化SiC/Cu复合材料性能，选变量为烧结温度（700~900 ℃），烧结压力（40~60 MPa），烧结保温保压时间（7~12 min），以致密度、硬度、抗弯强度、热导率和热膨胀系数为响应值，研究实验因素的交互作用，模拟并获取的最佳烧结温度、烧结压力、烧结保温保压时间分别为：826 ℃、50 MPa、10 min，并用模拟结果做了验证实验，试样的致密度、硬度、抗弯强度、导热率和热膨胀系数分别为99.32±0.45%、127±4 HRB、562±8 MPa、230.21±4 W/m·K和8.44±0.32×10^-6 /K，与理论值较符合。

SiC/Cu composites have excellent properties such as good thermal conductivity, high strength and high hardness, and are widely used in electronic packaging, heat transfer devices, aerospace fields (such as aircraft frames), automotive fields (such as brake pads, internal combustion engine pistons and engine impellers) and other fields. However, there are problems such as complicated preparation process, high cost and difficulty in obtaining products with high thermal conductivity and high strength, which limit their development and application. In this paper, SiC/Cu composites with high thermal conductivity, high strength and low expansion coefficient were prepared by powder metallurgy. The effects of sintering temperature, pressure and holding time on the mechanical and thermophysical properties of SiC/Cu composites were systematically investigated, and their properties were optimised using the response surface method to obtain the optimum preparation process parameters.

SiC/Cu composites were prepared by powder metallurgy hot pressing process, and the effects of process parameters such as sintering temperature, sintering pressure and holding time on the performance of the specimen were systematically studied. The results show that with the increase of sintering temperature, the density, hardness, flexural strength and thermal conductivity of the specimen first increase and then decrease, and when the sintering temperature is 800 °C, it is 99.1%, 569 MPa, 128 HRB, 220.47 W/m·K, respectively. The porosity is contrary to the density trend, and the minimum porosity is 0.9% when the sintering temperature is 800 °C. With increasing temperature, the coefficient of thermal expansion decreases from 10.43×10^-6 /K to 8.09×10^-6 /K. When the sintering pressure increases from 20 MPa to 60 MPa, the density increases, and then the increase is not large, the porosity decreases and tends to be flat. When the sintering pressure increases from 20 MPa to 60 MPa, the hardness of the specimen increases from 67 HRB to 130 HRB, and the coefficient of thermal expansion decreases from 9.12×10^-6 /K to 8.09×10^-6 /K. The flexural strength and thermal conductivity increased first and then decreased with the increase of sintering pressure, and when the sintering pressure was 50 MPa, the maximum values were 567 MPa and 224.72 W/m·K. With the increase of sintering insulation and holding time (2~22 min), the performance change trend of the sample is small, when the sintering holding time is 12 min, the density, porosity, hardness, flexural strength, thermal conductivity and thermal expansion coefficient of the sample are better, which are 98.58%, 1.42%, 118 HRB, 569 MPa, 225.13 W/m·K, 8.41×10^-6 /K, respectively. In summary, the optimal sintering temperature, sintering pressure and sintering holding time are: 800 °C, 50 MPa, 12 min, respectively.

On the basis of the best process parameters, the influence of SiC content on the performance of the specimen was studied, and the thermal conductivity of the specimen was predicted by Maxwell-Eucken model and the core-shell spheroid particle reinforced "composite thermal conductivity cube" model, and the thermal expansion coefficient of the composite was predicted by the ROM mixing law and the Turner model. The results show that the intermetallic compound AlCuMg generated in the sample greatly improves the strength of the material. When the SiC content was 35 vol%, the SiC particles were uniformly dispersed in the matrix, and the density, porosity, flexural strength, thermal conductivity and thermal expansion coefficient of the sample were the largest, which were 98.81%, 1.19%, 478 MPa, 254.76 W/m·K and 11.84×10^-6/K, respectively. With the increase of SiC content, the agglomeration of SiC particles is serious, the density, flexural strength, thermal conductivity and thermal expansion coefficient of the sample decrease, and the porosity increases. Its hardness showed a trend of first increasing and then decreasing, and when the SiC content was 45 vol%, it reached a maximum of 110 HRB. It is found that when the SiC content is low, the thermal conductivity predicted by the core-shell spheroid particle enhanced "composite thermal conductivity cube" model is consistent with the measured value, and the thermal expansion coefficient predicted by the Turner model is close to the measured value.

The response surface method (RSM) was used to further optimize the performance of SiC/Cu composites, and the variables were selected as sintering temperature (700~900 °C), sintering pressure (40~60 MPa), sintering holding time (7~12 min), with density, hardness, flexural strength, thermal conductivity and thermal expansion coefficient as the response values, and the interaction of experimental factors was studied, and the optimal sintering temperature, sintering pressure and sintering holding time were simulated and obtained: 826 °C, 50 MPa, 10 min, respectively The density, hardness, flexural strength, thermal conductivity and thermal expansion coefficient of the sample were 99.32±0.45%, 127±4 HRB, 562±8 MPa, 230.21±4 W/m·K and 8.44±0.32×10^-6 /K, respectively, which were in line with the theoretical values.