伪半固态触变成形制备SiCp/Al电子封装材料的组织与性能

采用伪半固态触变成形工艺制备了40%、56%和63%三种不同SiC体积分数颗粒增强Al基电子封装材料，并借助光学显微镜和扫描电镜分析了材料中Al和SiC的形态分布及其断口形貌，测定了材料的密度、致密度、热导率、热膨胀系数、抗压强度和抗弯强度.结果表明，通过伪半固态触变成形工艺可制备出的不同SiC体积分数Al基电子封装材料，其致密度高，热膨胀系数可控，材料中Al基体相互连接构成网状，SiC颗粒均匀镶嵌分布于Al基体中.随着SiC颗粒体积分数的增加，电子封装材料密度和室温下的热导率稍有增加，热膨胀系数逐渐减小，室温下的抗压强度和抗弯强度逐渐增加.SiC/Al电子封装材料的断裂方式为SiC的脆性断裂，同时伴随着Al基体的韧性断裂. 

Microstructure and properties of SiCp/Al electronic packaging materials fabricated by pseudo-semi-solid thixoforming

SiC particles reinforced Al matrix composites with three different SiC volume fractions of 40%, 56% and 63% for electronic packaging were prepared by pseudo-semi-solid thixoforming. The Al and SiC distribution and the fractographs of the SiCp/Al electronic packaging materials were examined by optical microscopy and scanning electron microscopy. The density, relative density, thermal conductivity (TC), coefficient of thermal expansion (CTE), compressive strength and bending strength of the SiCp/Al electronic packaging materials were tested. It is found that the SiCp/Al electronic packaging materials have controllable coefficients of thermal expansion and high relative density. The Al matrix is connected into a network, and SiC particles are uniformly distributed in the Al matrix. When the SiC volume fraction increases, the density and thermal conductivity at room temperature lightly increase, the coefficient of thermal expansion gradually decreases, and the compressive strength and bending strength increase. The main fracture mode of the SiC/Al electronic packaging materials is brittle fracture of SiC particles accompanied by ductile fracture of the Al matrix at the same time.