On the objective representations of kinematics in crystal plasticity

摘要

In crystal plasticity, the velocity gradients, deformation rates and spins in the process of plastic flow are represented by crystallographic shearing on specific slip systems. It is known that such representations describe the physical mechanisms of plastic deformation in crystal material. Obviously, the descriptions of material mechanisms must be objective or frame indifferent. However, in some literatures, non-objective representatins were employed. In this paper, the problems of the objectivity for the kinematics representations in crystal plasticity are discussed. The criteria of the objective representations in relaxed and current configurations are suggested. Some descriptions are analyzed and proved. A few objective representations are presented.