Comparative study and application of a coupled nonlinear kinematic hardening model for structural metallic material behavior

摘要

According to the experimental observation made by Phillips and Lee in 1979, the direction of the movement of the yield surface centre occurs between the stress rate tensor and the plastic strain rate tensor. When the plastic strains dominate the global behavior of the structure in question, the effect of the plastic flow rule can be unwitting overlooked. However, the application of more advanced engineering materials, e.g. high strength steel etc., is increasing and the ambiguity of plastic flow can not be ignored. Take the high strength steel of 420 Mpa as an example, a detailed comparative discussion of a coupled nonlinear kinematic hardening model is presented to account for such an experimental observation. A better prediction for the kinematic hardening behavior can be expected by adding a new term originally proposed by Frederick and Armstrong in 1996. In this work, the advantages as well as the accuracy for the coupled nonlinear constitutive model is discussed.