Plastic deformation and failure of solids with stress state dependent properties

Abstract

The plastic and strength properties of many structural materials depend on the type of external forces; in particular, they have different stress-strain curves under the conditions of uniaxial tension, uniaxial compression, different types of biaxial and triaxial loadings. This effect is concerned some structural features of polycrystalline alloys. Based on the analysis of experimental data, a possible approach to describe the dependence of plastic characteristics of materials on the stress state type realized under loading is proposed. The plasticity condition for the materials of stress state dependent properties is represented in corresponding generalized form, which includes some of well-known plasticity conditions in different particular cases. The constitutive equations to describe simultaneously the anisotropy and stress state dependence of plastic material properties are formulated. The results of experimental studies of plastic properties of aluminum alloy are analyzed with the use of proposed model.