Surface buffing and its effect on chloride induced SCC of 304L austenitic stainless steel

Abstract

The study focuses on the impact of buffing operation on the stress corrosion cracking (SCC) susceptibility of 304L austenitic stainless steel (SS). The SCC susceptibility of the buffed surfaces were determined by testing in boiling magnesium chloride (MgCl2) environment as per ASTM G 36. Test was conducted for 3hr, 9hr and 72hr to study the SCC susceptibility. Buffed surfaces were resistant to SCC even after 72hr of exposure to boiling MgCl2. The surface and cross section of the samples were examined for both before and after exposure to boiling MgCl2 and was characterized using optical microscopy. The study revealed that buffing operation induces compressive residual stresses on the surface, which helps in protecting the surface from SCC.