Evaluation of viscoplastic parameters of an austenitic stainless steel at high temperature

Metals at high temperatures are sensitive to strain rate effects and exhibit viscoplastic behavior. The Perzyna model is one of the most widely used ones to study rate-dependent plasticity. This paper presents the details of calibration of Perzyna model parameters of an austenitic stainless steel from tension tests and calibration of Chaboche and Voce model parameters from low-cycle fatigue test at 1000 K. Tests are conducted in an INSTRON 8862 electromechanical UTM. Perzyna model parameters are validated by comparing tension test results with finite element simulations using ANSYS (Version 16.0) software. Sensitivity of Perzyna model parameters on viscoplastic behavior is investigated for monotonic as well as cyclic loading situations. Perzyna model is combined with the Chaboche–Voce cyclic plasticity model for investigating cyclic loading. Finally, viscoplastic cyclic stress analysis of a double-walled rocket engine thrust chamber is carried out using a combination of Perzyna, Chaboche and Voce models and its cyclic life evaluated. © 2018, Springer Nature Singapore Pte Ltd.