Stress Relaxation Behavior of a Nb-Stabilized Austenitic Stainless Steel at 550

Stress relaxation resistance is one of the most significant properties that are critical to the service life of the fasteners. In this study, the stress relaxation behavior of a Nb-stabilized austenitic stainless steel was investigated. It was revealed that the homogenization treatment at 1250 ℃ could make more primary NbC particles dissolved back into the matrix and consequently get a great number of nano-sized secondary NbC carbides. Therefore, the stress relaxation resistance will be enhanced due to the effective pinning of such higher density of nano-sized secondary NbC carbides on the dislocation movement.