On the strengthening mechanisms of high nitrogen austenitic stainless steels

• High-N stainless steels with yield strength of 1060 MPa were obtained by hot rolling. • Dislocation density is the main strengthening contributor after hot rolling. • Increasing N and C content improves plasticity in annealed or rolled conditions. The effect of microstructure and dispersion of secondary phases on tensile mechanical properties of two high nitrogen austenitic stainless steels subjected to annealing or rolling at 1000 °C was studied. The solid solution strengthening gave the main contribution to overall strength after annealing. Similar strength contribution was provided by the dislocation density after rolling that resulted in almost twofold increase in the yield strength.