Development of non Masing characteristic model for LCF and ratcheting fatigue simulation of SA333 C–Mn steel

• Elegant formulation of cyclic hardening is proposed with new memory function.
• Low cycle fatigue simulation shows good co-relation with the experiments.
• Influence of loading history and magnitude of SA333 C–Mn steel are demonstrated.
• Effect of mean strain on mean stress and non Masing characteristics are simulated.
• In all load cases, prediction of ratcheting strain is improved in transient cycles.

In this paper, finite element based cyclic plasticity model of SA333 C–Mn steel has been developed incorporating non Masing and cyclic hardening characteristics of the material. In the proposed model, a new fading memory stress function has been introduced in the recovery term of the kinematic hardening rule to simulate the cyclic hardening behavior of the material under strain controlled loading cycles. Evolution of the yield stress during cyclic plastic deformation process has been introduced through exponential function of accumulated plastic strain. The present formulation has demonstrated the non Masing behavior and cyclic hardening characteristic of SA333 C–Mn steel material similar to the experimental observations. A number of experiments have been performed to investigate the LCF and ratcheting characteristics of the material. Material constants are derived from the experimental data. In the present paper, LCF and ratcheting phenomena have been simulated by developing a FEM model with axisymmetric round specimen and the new cyclic plasticity formulations have been incorporated in the material model. The fading memory stress function, which is dependent on the loading history, leads to better realization of cyclic hardening and ratcheting phenomenon in the transient cycles as observed from the simulation and experimental results.