Experimental and numerical studies of the effect of particle size on the deformation behavior of the metal matrix composites

By incorporating the Taylor-based nonlocal theory of plasticity, the finite element method (FEM) is applied to investigate the effect of particle size on the deformation behavior of the metal matrix composites. The contributions of various strengthening mechanisms to overall composite strengthening, and the impact of particle size on each mechanism were explicitly evaluated. Both numerical and experimental results indicate that, at a constant particle volume fraction, there is a close relationship between the particle size and the deformation behavior of the composites. The yield strength and plastic work hardening rate of the composites increase with decreasing particle size. The predicted stress-strain behaviors of the composites are qualitative agreement with the experimental results. It is also found that the particle size has a significantly effect on the dislocation strengthening mechanism, but little on the load transfer strengthening mechanism. (c) 2006 Elsevier B.V. All rights reserved.