Three-dimensional multi-particle FE model and effects of interface damage, particle size and morphology on tensile behavior of particle reinforced composites

In this article, we developed a three-dimensional multi-particle finite element model to explore the effects of particle size, morphology and interfacial strength on the elastic-plastic behavior of particle-reinforced composites under uniaxial tension. We adopted strain-gradient plasticity to evaluate the size-dependent strengthening effect on matrix. Randomly distribution of spherical or cubic particles was realized in a cubic representative cell and interface damage was described by the cohesive zone model. Numerical analysis quantified the effects of microstructural features on interface damage, load transfer and strengthening effect in matrix: the flow strength of composites increases with decreasing particle size, which is attributed to the increased size-dependent strengthening in matrix, considering that the load bearing capacity of particles is decreased simultaneously. Weaker interface results in earlier and faster development of interface damage, and as the interface damage grows to the order of 0.1, load bearing capacity of particles drops from its peak value.