A simple integration algorithm for a non-associated anisotropic plasticity model for sheet metal forming

In this paper, an anisotropic material model based on a non-associated flow rule and nonlinear mixed isotropic-kinematic hardening is developed. The quadratic Hill48 yield criterion is considered in the non-associated model for both yield function and plastic potential to account for anisotropic behavior. The developed model is integrated based on fully implicit backward Euler's method. The resulting problem is reduced to only two simple scalar equations. The consistent local tangent modulus is obtained by exact linearization of the algorithm. All numerical development was implemented into user-defined material subroutine for the commercial finite element code ABAQUS/Standard. The performance of the present algorithm is demonstrated by numerical examples. Copyright (c) 2015 John Wiley & Sons, Ltd.