Analysis of shear band instabilities in sintered metals

For structural components made of sintered metals the porosity may be rather high\ and this a}ects conditions for material failure[ A simple model for analysis of shear band development in uniformly strained solids is used here to study the e}ect of rather high initial porosities on the onset of a material instability[ The elastic plastic behaviour of the material is represented by a material model\ which combines the Gurson model\ relevant to rather low porosities\ with theFKMmodel\ developed for high porosity powder compacts[ Predictions are shown for various levels of initial porosity and for various levels of initial material imper! fections\ considering both plane strain and axisymmetric conditions outside the shear band[ Also a com! parison of localization predictions by the Gurson model\ the FKM model and the combined model is presented