Damage evolution and characterization for sintered powder metals with the varying porosity

Micro-structure of sintered powder metals is characterized by the high porosity. Experiments confirm that the major mechanical property can be expressed in a power-law function of the porosity. In the present work the interdependence between the porosity and the elastic-plastic mechanical property as well as the damage evolution in sintered metals with varying porosity is investigated experimentally and analytically. A damage characterization is introduced based on the stiffness degradation to predict the inelastic behavior of the sintered material and the damage process. The proposed damage evolution model is further verified under multi-axial loading conditions.