Technical Paper
Thermomechanical Fatigue Behavior and Life Modeling of An Austenitic Stainless Steel
2024-04-09
2024-01-2683
Austenitic stainless steel (1.4837Nb) is widely used for turbo housing and other components which are subjected to elevated temperature conditions. Due to assembly constraints, geometry limitation, and particularly high temperatures, thermomechanical fatigue (TMF) issue is commonly seen in the service of the components. Therefore, it is critical to understand the TMF behavior of the steel. In the present study, a series of fatigue tests including isothermal low cycle fatigue (LCF) test at elevated temperatures up to 1000°C, in-phase and out-of-phase TMF tests in different temperature ranges have been conducted. Both creep and oxidation are active in these conditions, and their contributions to the damage of the steel are evaluated. A Chaboche viscoplasticity model for constitutive simulation, and a DTMF damage model for life prediction are developed and validated at specimen level.