How to use manganese and nitrogen instead of nickel chromium nickel stainless steel in principle

Cr-ni austenitic steel advantage although a lot of, but in recent decades because of nickel-base heat resistant alloy and nickel of less than 20% of the heat intensity development and application of steel, and the growing development of chemical industry of growing demand for stainless steel, nickel and mineral deposits is less and concentrated distribution in minority areas, therefore appeared worldwide nickel in terms of supply and demand contradiction. So in the field of stainless steel and many other alloy ( Such as large castings and forgings steel, tool steel, refractory steel, etc. ) , especially the relative lack of resources of the country of nickel, nickel widely carried out section and other elements for scientific research and production practice of nickel in this aspect research and application of more on manganese and nitrogen instead of nickel in stainless steel and heat resistant steel. The role of manganese in austenite is similar to nickel. But some say exactly, the effect of manganese is not formed austenite, but is that it slows the critical quenching of steel, increase the stability of austenite during cooling, inhibit austenite decomposition, keep high temperature to form austenite to to room temperature. 4% change, also do not make the corrosion resistance of steel in the air and acid obvious change. This is because the manganese to enhance the role of iron base solid solution of electrode potential is not big, the formation of oxide film of protection is also very low, so the industry is to manganese alloying austenitic steel ( Such as mn18cr4 40, 50 mn18cr4wn, ZGMn13 steel, etc. ) , but they cannot be used as stainless steel. Manganese stability of austenite in the steel is about half of the nickel, 2% of nitrogen in the steel is also stable austenite, and effect degree bigger than the nickel. For example, to make containing 18% chromium steel at room temperature for austenitic organization, generation of nickel with manganese and nitrogen low nickel stainless steel and the nickel, and chromium manganese nitrogen not steel has been used in industry, and some of which have been successfully replaced the classic 18 8 chromium nickel stainless steel.