Abstract: | ![]() Eringen's and Trusedell's polar decomposition are formulated by explicit formulation of displacement field, based on Chen's additive decomposition of deformation gradient. Then the strain introduced by the multiplicative decomposition and the strain introduced by the additive decomposition are formulated explicitly with displacement gradient. This formulation clears the intrinsic contents of strains defined by taking the Eringen's and Trusedell's polar decomposition. After that, Chen's strain definition was introduced to show that the plastic deformation can be understood as the irreversible local average rotation. For initial isotropic simple elastic material, the research shows that path-dependent feature of classical plasticity theory is naturally expressed in Chen's strain definition. For rate-independent plasticity, the related deformation stress was discussed. The research shows that for isotropic hardening material the relation equation between the required geometric configuration and the corresponding loading field is explicitly formulated. Hence, for metal forming, this paper explicitly formulates the related fields by displacement field and invariant elastic constants. |