SiC_(p)表面化学镀Cu对Al基复合材料组织和性能的影响

Effects of Electroless Copper Plating on Surface of SiC on Microstructure and Properties of Al-matrix Composites

采用化学镀覆的方法对SiC_(p)表面进行镀Cu处理,以2024铝合金为基体,通过直热法粉末触变成形工艺制备了SiC_(p)体积分数为60%的Al基复合材料,研究了Cu镀层对复合材料显微组织、相组成、断裂行为、抗弯强度和热膨胀系数的影响。研究发现,SiC_(p)经过镀Cu处理后,复合材料的组织由AlCu、Al_(2)Cu为主的金属间化合物组成,对复合材料的性质和性能产生了较大影响。新相AlCu、Al_(2)Cu的出现,显著降低了复合材料的热膨胀系数。与未镀Cu的SiC_(p)/2024Al复合材料相比,镀Cu后复合材料的致密度为99.15%,提高了1.57%;热膨胀系数为5.73×10^(-6) K^(-1),降低了32.4%;抗弯强度为283 MPa,降低了10.2%。

The surface of SiC_(p) was coated with Cu by electroless plating method. Taking 2024 Al alloy as the matrix, 60%SiC_(p)/Al-matrix composites were prepared by direct-heating powder thixoforming process, and the effects of Cu coating on the microstructure, phase composition, fracture behavior, flexural strength and thermal expansion coefficient of composite were investigated. The results indicate that after Cu plating, the matrix of the composite is composed of intermetallic compounds dominated by AlCu and Al2Cu, which has a greater impact on the properties and performance of the composites. The thermal expansion coefficient is significantly reduced due to the appearance of new phases AlCu and Al_(2)Cu in the matrix. Compared with the SiC_(p)/2024 Al composite without copper plating, the relative densities of the material after copper plating are 99.15%, which is increased by 1.57%. The coefficients of thermal expansion are 5.73×10^(-6) K^(-1), which is reduced by 32.4%. The flexural strength are 283 MPa, which is reduced by 10.2%.