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DETERMINATION OF SUBSEQUENT YIELD SURFACES USING A COROTATIONAL CONSTITUTIVE MODEL FOR RIGID PLASTIC HARDENING MATERIALS

In this paper, the application of different corotational rates in the constitutive modeling of rigid plastic hardening materials at large deformations is considered. For this purpose, a corotational constitutive model for kinematic and isotropic hardening materials, obeying the von mises yield criterion, is used. By applying this constitutive model, the subsequent yield surfaces are determined for the simple shear problem. It is noted that all corotational rates give the same yield surface for this problem. The yield surface moves in the direction of the stress increment vector for kinematic hardening materials. Also, in the case of combined hardening materials, the motion direction of the yield surface center will become coincident with the stress increment vector as the deformation increases.