Particle distribution-dependent micromechanical simulation on mechanical properties and damage behaviors of particle reinforced metal matrix composites

Abstract

A micromechanical simulation has been performed to study the effect of particle distribution on the mechanical properties and damage behaviors of particle reinforced metal matrix composites (PRMMCs). Two-dimensional (2D) representative volume elements with variable particle size, volume fraction and particle distribution were generated and subjected to finite element simulation. An enhanced continuum model, which incorporates dislocation punching effect at particle-matrix interfaces and Taylor-based nonlocal theory of plasticity in matrix, was used to simulate the mismatch in coefficients of thermal expansion strengthening and particle size-dependent strengthening. Additionally, constitutive damage behaviors were involved in simulating the crack initiation and evolution, considering the ductile damage in matrix and dislocation punching zone, as well as the particle cracking. Simulation results indicate that refining the particle size is helpful to improve the tensile strength and fracture resistance of PRMMCs, whereas the increase of particle clustering volume fraction or severity facilitates damage evolution and deteriorates the mechanical properties. Statistical analysis indicates a negative linear dependence between particle distribution homogeneity and the ductility, given a constant particle size and volume fraction.