Crevice Corrosion Resistance of Commercial and High-Purity Experimental Stainless Steels in Marine Environments—The Influence of N, Mn, S

A major use of stainless steel is in chloride-containing environments; the limiting factor that most frequently determines an alloy's suitability to such environments is its crevice corrosion resistance. The objective of this work was to examine in detail the effect of minor elements on the crevice corrosion resistance of stainless steels ranging from the type 316 (UNS(1) S31600) alloy to the 6% molybdenum austenitic stainless steels (SS) in order to define an alloy composition that would be suitable for seawater service. To this end, eight commercial stainless steels together with 31 high-purity experimental alloys have been assessed for resistance to crevice corrosion initiation in seawater environments using an accelerated test technique. Overall, the results indicate the feasibility of significantly improving the corrosion resistance of the high-alloy austenitic stainless steels to the point where they would be suitable for seawater service.