Large internal stresses in particle-reinforced composites subjected to dynamic loads

Discontinuously reinforced particulate composites are often used in applications where they may be subject to dynamic mechanical loads. A rational analysis of composites under these loadings to predict the initiation of failure and its subsequent accumulation must concentrate on the stress state at the microstructured level. In this study, the steady-state stresses resulting from a dynamic loading in a particle-reinforced metal-matrix composite are determined, and the stress concentration factors at the interface between the particle and matrix are obtained in an effort to determine the parameters which govern the dynamic response. It is found that the dynamic stress concentrations are dependent on the frequency of excitation and elastic properties of the composite, and they can be larger than those encountered under static loading. (C) 1999 Elsevier Science Ltd. All rights reserved.