Modeling of cyclic stress–strain behavior and damage mechanisms under thermomechanical fatigue conditions

A multi-component model was applied to predict the cyclic stress–strain response of different alloys under thermomechanical fatigue conditions based upon isothermal hysteresis loops. A ductile AISI 304 L-type stainless steel and two high strength alloys, the near-α titanium alloy IMI 834 and the nickel-base superalloy IN 100, were chosen as test materials. These represent alloys with rather different dislocation slip modes, stress–strain characteristics and damage mechanisms. Model predictions are compared with experiments and the differences in cyclic stress–strain response and damage mechanisms under isothermal and thermomechanical fatigue conditions, respectively, are discussed based upon microstructural observations.