An Elastic-Plastic Constitutive Equation Taking Account of Particle Size and Its Application to A Homogenized Finite Element Analysis of A Composite Material

摘要

Composite materials have complicated microstructures. These microstructures affect the macroscopic deformation of composite materials. In the present study, we focus on the effect of particle size in a particle-dispersed composite material on the mechanical strength of the material. For this purpose, we derived a macroscopic elastic-plastic constitutive equation using a modified version of the Eshelby's equivalent inclusion method combined with the gradient plasticity. We incorporated this macroscopic elastic-plastic constitutive equation into a finite element program and performed a homogenized finite element analysis of a particle-dispersed composite material in which both the macroscopic and microscopic behaviors of the composite material were obtained. The present method successfully revealed the size effect in a particle-dispersed composite material, namely that its mechanical strength increases with a decrease in the particle size.