SiCp粒径及含量对铝基复合材料拉伸性能和断裂机制的影响

Influence of SiCp Size and Content on Tensile Properties and Fracture Mechanism of SiCp/Al Composites

摘要: 采用冷压烧结和热挤压方法制备出不同体积分数(1.5%,5%)亚微米(130 nm)和微米级(14 μm)的SiCp增强铝基复合材料,并对其拉伸性能及断口形貌进行了分析.结果表明：粒径为130 nm 的SiCp 增强的铝基复合材料抗拉强度随着体积分数的增加而提高,其断裂机制是在Al-SiC界面处的铝基体撕裂形成的空洞和裂纹扩展为主;而粒径为14 μm的SiCp增强的铝基复合材料的抗拉强度随着体积分数的增加而降低,其断裂机制为部分SiCp的解理断裂并沿基体扩展的复合过程.

Abstract: Al matrix composites reinforced with various sizes and contents of SiCp were fabricated via powder metallurgy followed by hot extrusion,and their tensile properties and fractographs were examined.The results show that with the increase in SiCp(130 nm) volume fraction,the tensile strength increase,their breakage is due to tearing of the matrix near interface.With the increase in SiCp(14 μm) volume fraction,the tensile strength decrease,composite failure resulted from cleavage cracking of SiCp and propagation going along matrix.