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In this paper we present a continuum theory for large strain anisotropic elastoplasticity based on a decomposition of the modified plastic velocity gradient into energetic and dissipative parts. The theory includes the Armstrong and Frederick hardening rule as well as multilayer models as special cases even for large strain anisotropic elastoplasticity. Texture evolution may also be modelled by the formulation, which allows for a meaningful interpretation of the terms of the dissipation equation.

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Many authors have observed experimentally that the macroscopic yield surface changes substantially its shape during plastic flow, specially in metals which suffer significant work hardening. The evolution is frequently characterized by a corner effect in the stress direction of loading, and a flatter shape in the opposite direction. In order to incorporate this effect many constitutive models for yield surface evolution have been proposed in the literature. In this work we perform some numerical predictions for experiments similar to the ones performed in the literature using a multilayer kinematic hardening model which employs the associative Prager's translation rule. Using this model we prescribe offsets of probing plastic strain, so apparent yield surfaces can be determined in a similar way as it is performed in the actual experiments. We show that similar shapes to those reported in experiments are obtained. From the simulations we can conclude that a relevant part of the apparent yield surface evolution may be related to the anisotropic kinematic hardening field.