A porosity-dependent inelastic criterion for engineering materials

Many criteria have been developed to describe the yielding condition, plastic potential, and failure strength of engineering materials. In this paper, the authors first review the characteristics of a few of the more common criteria used for porous materials. It is then shown that the main features of many criteria can be represented by a unique set of recently developed equations. The ensuing multiaxial criterion becomes applicable to a variety of materials and loading states. One of the advantages of the proposed criterion, named MSDP_u, is that it is explicitly porosity-dependent. The validity of this general inelastic criterion is demonstrated using experimental results obtained from various types of materials. A brief discussion follows on the advantages and limitations of the proposed equations.