Adding micro-alloy elements Ti, Nb, and V in a martensitic stainless steel tube is usually expected to form a nitrogen compound with C and N. As a result increasing the strength of the steel. Ti is a stabilizing element.
At the same time, it is a fine crystalline element. Ti can form a variety of stable carbon-nitrogen compounds. Finally, Ti (C, N) can increase the toughness without sacrificing strength. The addition of 0.1% Nb in CA6NM martensitic stainless steel can reduce the precipitation of the rich Cr ions. Because Nb can combine with C and N atoms to form nanometer grade Nb rich precipitates (5-15nm). The homogeneous distribution of rich Nb precipitates can increase the strength of the steel and hence optimize its plasticity and toughness.