Application of a Constitutive Model for Simulating Thermo-Mechanical Fatigue for Austenitic Stainless Steel.

Austenitic stainless steels are one choice of material that is used within steam and gas turbines components. This material shows adequate mechanical properties at high temperatures, high corrosion resistance, and relatively cheaper processing costs making them a viable choice for the components. This work primarily focused on a specific series of stainless steel for use within constitutive models. The use of constitutive models allows for simulations of various loading conditions to better improve the service life of materials. Using constitutive models, simulations can be done to replicate the behavior of the material undergoing thermos-mechanical fatigue (TMF) and low cyclic fatigue (LCF) to represent service conditions that the material can experience when under complex loading conditions. A modified unified Chaboche viscoplasticity model is tested to determine the validity of the use of the model with temperature dependence for this type of stainless steel. The results are compared with isothermal and LCF data from generic steel of the stainless steel series.