Homogenization of the average thermo-elastoplastic properties of particle reinforced metal matrix composites: The minimum representative volume element size

The average thermo-elastoplastic properties of particle reinforced metal matrix composites (PRMMC) including the average coefficient of thermal expansion (CTE), Young’s modulus, Poisson’s ratio and isotropic hardening function are investigated. Computational homogenization method based on 3D realistic microstructures (RMs) is employed. Unit cell microstructure (UCM) based model and analytical models are also employed for comparison. As an illustration, 17 vol.%SiCp (3 μm)/2124Al composite is studied. Compared to RMs, UCM underestimates the average CTE and Poisson’s ratio, while it overestimates the average Young’s modulus and isotropic hardening function. The minimum representative volume element (RVE) size for determining the average CTE, Young’s modulus and Poisson’ ratio is δ = 15, δ = 20 and δ = 20, respectively, where δ is the size ratio of microstructure model, which is defined by the ratio of the side length of the RVE to the nominal mean radius of reinforcement. The minimum size of RVE for estimating average isotropic hardening function of plastic deformation is dependent on both the temperature and the plastic deformation condition.