【摘要】 利用动态 Hopkinson装置和 Instron 40 2 6测试了 15 % Si CP/Al- 5 Cu、 15 % Si CP/2 12 4、15 % Si CP/Al- L i、15 % Si CW/6 0 6 1和 30 % Si CP/6 0 6 1铝合金等几种复合材料的准静态和冲击力学性能 ,探讨了应变率等对于强度、硬化模量和失效应变等的影响。同时观察了上述材料动态拉伸断口 ,揭示了金属基复合材料破坏的几种不同控制机理。最后讨论了实验中发现的上述复合材料拉压不对称性的新特征 ,其中考虑了金属基复合材料的热失配应力和不同的损伤、破坏控制机理更多还原

【Abstract】 In this paper, the mechanical behaviors of 2124, Al 5Cu, Al Li and 6061 alloys reinforced by silicon carbide particulate, together with the silicon carbide whisker reinforced 6061 Al alloy, were studied under quasi static and impact loading conditions, by using the Split Hopkinson Tension / Compressure Bars and Instron universal testing machine. The effect of the strain rate on the UTS, hardening modulus, and failure strain was investigated. At the same time, the SEM observations of dynamic fracture surfaces of various MMC materials showed some distinguished failure characteristics, which determined the sensitivity of the strain rate of failure strain and the asymmetry of tension and pressure of MMC materials. Some new characteristics of asymmetry of mechanical behaviors of MMC materials under tension and compression loadings were also presented and explained in details in this paper, which can be considered as flags, to some degree, to determine the controlling mechanism of damage and failure of metal matrix composites under impact loading. The development of new constitutive laws about MMC materials under impact loadings should benefit from these experiment results and theoretical analysis.更多还原