A multiaxial cyclic plasticity model for non-proportional loading cases (Q1973717)

From the conclusions: We propose a two-surface plasticity model for non-proportional loading using a nonlinear hardening rule with evanescent memory evolution. The additional term incorporated in the Armstrong-Frederick kinematic hardening rule for cyclic loading is modified to account for continuous non-proportional stress loading paths. The material constant associated with the proposed new term is expressed in a functional form to account for the variation in the loading direction.