Micromechanical Analysis of SiC/Al Metal Matrix Composites: Finite Element Modeling and Damage Simulation

The influence of interface strengths and microstructures on the strength and damage of SiC particle reinforced aluminum Metal Matrix Composite (MMC) is investigated under uniaxial tensile, simple shear, biaxial tensile and combined tensile and shear loadings. An algorithm to generate automatically the microstructural models of MMCs with random distribution of particle shapes, dimensions, orientations and locations is proposed and implemented within Matlab. A damage model based on the stress triaxial indicator is developed to simulate the ductile failure of metal matrix, the other damage model based on the maximum principal stress criterion is developed to simulate the brittle failure of SiC particles, and 2D cohesive element is utilized to describe interface decohesion between matrix and particles. A series of numerical experiments are performed to study the macroscopic stress-strain relationships and microscale damage evolution in MMCs under different loading conditions.