Influence of Nickel Content on the Properties of High Nitrogen Austenitic Stainless Steels

摘要

In this study, the influence of nickel content on the corrosion and mechanical properties of Fe-8Mn-21Cr-4Mo-1. 2N steel grades produced through a pressurized induction furnace, which contained nickel content of up to 5mass% , were investigated. The solution annealing temperature should be increased with the nickel content to prevent the formation of chromium nitride, which is detrimental to corrosion resistance. The nickel-bearing steels maintain low magnetic permeability, even when subject to 70% cold worked condition, while the magnetic permeability of the nickel-free steel slightly increases with cold working. Nickel addition of up to 5mass% has no significant effect on work hardening behaviour and renders it ductile to brittle transition behaviour. The nickel release rate of all of the experimental steels was below 0.5μg·(cm~2·week)~(-1), as defined by the European Standard EN1811. None of the experimental steels showed any evidence of pitting below 333 K in the Critical Pitting Temperature test. The depassivation pH also revealed no difference among the experimental steels. It is confirmed that the nickel addition has little influence on corrosion and mechanical properties and that it contributes to austenite stability in these steel grades.