Damage Analysis of Aluminum Matrix Composite Considering Non-Uniform Distribution of SiC Particles.

Abstract

In this study, based on the fracture surface observations using a SEM (Scanning Electron Microscope), a numerical unit model and 3-dimensional non-uniform models for FEM (Finite Element Method) analyses are proposed using Gurson's model as a constitutive equation. The effect of the non-uniformity, the reinforcement volume fraction and the aspect ratio are considered for the quantitative evaluation of the stress-strain relationship of SiC particle-reinforced aluminum alloy. The results show that the dimple fracture process of the matrix aluminum alloy is well simulated after a large amount of plastic deformation. The non-uniformity of the SiC reinforcement locations and the aspect ratio have a strong effect on the local and global damage behavior and the stressstrain relations. It is shown that the fracture strain greatly increases when the aspect ratio of SiC particles is nearly 1.0, and the SiC particles are distributed uniformly. To improve both tensile strength and fracture strain, it is better to increase the SiC particle volume fraction rather than to increase the SiC particle aspect ratio. The numerical model is improved by considering the nonuniformity effect on the tensile stress and fracture strain.