Effect of Nitrogen on Creep Properties of 22Cr-25Ni Austenitic Heat-Resistant Steels

Abstract

The effect of nitrogen on creep properties of 22Cr-25Ni austenitic heat-resistant steels with different nitrogen content was studied. The tensile and creep strength increased with increasing nitrogen content. The tensile strength increased due to grain refinement by Nb-rich carbonitride. The creep strength increased with increasing nitrogen content because nitrogen retarded the formation and growth rate of Cr-rich carbide and the growth rate of Nb-rich carbonitride during creep.