Hot Tensile Deformation and Fracture Behavior of a Nitrogen Alloyed Ultralow Carbon Austenitic Stainless Steel

Abstract

The hot tensile deformation and fracture behavior of a nitrogen alloyed ultralow carbon austenitic stainless steel were studied by a Gleeble-1500D thermo-mechanical simulator with the temperature range of 11731473 K and strain rate range of 0.011 s ¹1 . Microstructural evolution was analyzed in terms of fractography at various deformation temperatures and strain rates. The tensile true stress-true strain curves after necking were calculated by the heuristic method. The fracture threshold values of the studied steel were estimated by finite element method (FEM). The final load-stroke curves obtained from the FEM simulation were found to have a good agreement with the experimental load-stroke curves. The quantitative relationship between fracture threshold value and Zener-Hollomom parameter was also established. The results are beneficial to the understanding of hot deformation behavior of a wide range of stainless steels.