A study of cyclic plasticity and viscoplasticity in a new nickel-based superalloy using unified constitutive equations. Part II: Simulation of cyclic stress relaxation

Cyclic stress relaxation behaviour has been investigated during strain hold periods under dwell loading conditions. A dynamic recovery term was introduced in the non-linear kinematic hardening rule and incorporated into the unified Chaboche model. The material parameters associated with this new term were determined and optimisation procedures were followed to obtain a new set of optimised parameters. The modified Chaboche model was then used in the simulation of creep and cyclic stress relaxation of a new nickel-based alloy, and the simulations were compared with the experimental results. Good agreement has been achieved between the numerical solutions and the experimental results. Correlation of the material parameters was also examined to evaluate the efficiency of the new model formulation.