Interest in the use of non-magnetic stainless steels for ship hull construction has focused attention on candidate coating systems with antifouling resistance. This attention is elevated by the knowledge that
subject austenitic grades are not inherently fouling resistant, and, in some cases, may be prone to. localized corrosion at marine attachment, e.g., barnacles, sites. Moreover, it has already been demonstrated that coating of candidate austenitic alloys with epoxy and epoxy + antifouling paint systems can promote crevice corrosion at coating-to-bare metal interfaces, especially when the surface area of the latter becomes large. Various investigations are underway by different researchers to identify a compatible coating system to minimize fouling without creating adverse conditions for crevice corrosion. This paper describes a nine-month seawater test program involving exposure of 240 stainless steel test specimens, mostly treated with water-base and solvent-base silane and topcoated with ablative Cu antifouling paint. Interim, three-month, test results presented indicate marked improvement in localized corrosion
resistance for silane treated "20Cr-6Mo" stainless steel (UNS N08367) over that exhibited by test specimens coated with epoxy alone. These same benefits were not observe when the silane treatments, formulated for the N08367 alloy, were applied to UNS S31603.
Keywords: austenitic stainless steels, crevice corrosion, seawater, silane, antifouling paint