Оn the micromechanical description of rate sensitivity of porous bodies

Abstract

The micromechanical foundation and the general structure of constitutive equations for cold and hot deformation of porous materials is considered. The model is based on analysis when the unit cell is considered as a hollow cylinder. The behavior of material is described in framework of modified model of non–linear viscose body. New macroscopic model, which derived from the some thermodynamics principles and takes into account the rate sensitivity, is based on the expression for averaged energy dissipation rate per unit volume. In particular case of plastic flow of matrix material the model developed in paper is transformed to well known Gursons model.