Modification of corrosion resistance by single and multi-element implantation into 304 stainless steel

Aqueous corrosion behaviour of ion implantation with molybdenum, yttrium, titanium and nitrogen on 304 austenitic stainless steel in acid solution was investigated by electrochemistry and surface analysis. Results show that the corrosion resistance of implanted samples has been evidently improved. After implantation the free corrosion current and passive current density of alloys reduce, and the breakdown potential grows up in chloride-containing solution. By AES analysis, it is found that the implanted element demonstrates a normal distribution in the surface layer. Besides the alloying action of implanted elements, the physical effectiveness such as radiation, displacement and sputtering during the implanting process also has a modification on corrosion resistance. (C) 1998 Elsevier Science S.A. All rights reserved.