Effect of cold working on mechanical properties of high-nitrogen 18Mn-18Cr austenitic steels

The effects of nitrogen content, cold working, and stress relief treatment on the mechanical properties of high-nitrogen 18Mn-18Cr austenitic steels with different nitrogen content are investigated with respect to the specimen direction and location. The yield and tensile strengths usually increased with increasing nitrogen content and cold working, and they additionally increased after stress relief treatment. Based on these results, we propose a semi-empirical equation to predict the yield and tensile strengths of high-nitrogen 18Mn-18Cr austenitic steels. On the other hand, we discuss the ductile-brittle transition behavior depending on cold working and stress relief treatment in terms of the temperature sensitivty of yield stress.