颗粒分布对金属基复合材料激光热冲击破坏的影响

从宏观和微观两方面研究了ＳｉＣ颗粒分布状况对陶瓷颗粒增强金属基复合材料激光热冲击破坏的影响，发现微裂纹形成是由基体内的孔洞和颗粒与基体脱胶所引起，而陶瓷颗粒分布不均匀对裂纹的扩展机理有重要影响，它大大降低了复合材料的宏观力学性能

THE EFFECT OF PARTICLE DISTRIBUTION ON THERMAL FAILURE IN PARTICULATE REINFORCED METAL MATRIX COMPOSITES INDUCED BY LASER

Thermal failure of particulatereinforced 6061 aluminum alloy composites with two kinds of particle distribution has been investigated. The thermal failure was induced by the coupled load of laser thermal shock and mechanical load. The initiations of microfracture in composites for homogeneous and heterogeneous particle distributions are both in the form of void in matrix or decohesion at the interface between the particle and the matrix. However, their mechanisms of the crack propagation are very different. The macrocrack formation is produced in the form of the separation of the SiC particlematrix interface or in the form of void nucleation and growth within the matrix for the composites with homogeneous particles distribution. However, for the composites with heterogeneous particles distribution, the reinforcement SiC particle fracture is the dominant damage mechanism for macrocrack proagation. As the results of the different microbehavioures of the composites, their mechanical properties are different. The strength of the composties with heterogeneous particle distribution is very lower than that of the composites with homogeneous particles distribution.