Investigation into the Effects of Prior Plasticity on Creep Accumulation in 316H Stainless Steel

Abstract

Steel components in the boilers of nuclear reactors are subject to high temperatures and varying loading conditions. This can introduce time-dependent and time-independent plasticity, which can interact with one another. Specimens of 316H austenitic stainless steel were heated to 550 °C and tensile pre-strained to 8%, 11% and 14% followed by 200 h, 280 MPa creep tests. These tests showed an increase in creep resistance with increasing tensile pre-strain. Macroscale simulations using RCC-MR deformation laws proved ineffective at predicting this interaction. Microscale crystal plasticity simulations proved effective at predicting the trends observed experimentally, hence demonstrating the potential of crystal plasticity as a predictive tool for structural integrity analysis.

Keywords

• stainless steel
• creep
• plasticity
• pre-straining
• crystal plasticity
• finite element analysis