Rate-dependent constitutive modelling and micro-mechanical analysis of fibre-reinforced metal-matrix composites

A rate-dependent elastic-plastic constitutive model is presented which was implemented into a finite element code. As an illustration, this model is u sed in a micro-mechanical analysis of a fibre-reinforced metal matrix compo site laminate. The matrix (a titanium alloy) is a rate-dependent material w hile the fibre behaves elastically. The residual stresses due to mismatch o f the thermal expansion of the matrix and fibre are determined first. The t hree-dimensional finite element prediction of the representative volume ele ment, which includes a debonding criterion, is found to be in good agreemen t with the experimental data in the linear and nonlinear regimes as well as the unloading part of the stress-strain curve. This success is attributed to the accurate representation of the matrix material properties by the rat e-dependent constitutive model, and proper simulation of the fibre/matrix i nterface debonding. (C) 2001 Elsevier Science Ltd. All rights reserved.