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 conse-quently 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.