Inelastic design for type 316L stainless steel at ambient and 600 °C under uniaxial loading

Abstract

This study aims to determine the safe elastoplastic shakedown limit of type 316L stainless steel at room temperature and at an elevated temperature of 600°C. Components made of type 316L stainless steel are commonly subjected to combined thermomechanical loads in various engineering applications. Shakedown based designs can be used to expand the feasible design space under combined thermomechanical cyclic loading conditions compared to conventional yield-limited designs. Extensive experimental and numerical effort has been made to model ratchetting and cyclic hardening/softening of stainless steels under uniaxial cyclic loading but a very limited number of studies have focused on determining the shakedown limit. In this work, shakedown limits are determined experimentally and numerically. A numerical model that combines time-dependent creep deformation and time-independent hardening is used to develop Bree load-interaction diagrams. It is found that shakedown occurs at room temperature at stress levels up to two times the linear elastic limit of the material and is limited by the time-dependent creep deformation. At 600oC, an enhanced shakedown behavior is observed that expands the feasible design space up to 4 times the linear elastic limit.