Effect of surface mechanical attrition treatment on stainless steel corrosion

Surface mechanical attrition treatment (SMAT) is a unique method for the nanoscale refinement of a surface grain structure without changing the alloy chemical composition. Herein, the effect of SMAT on the corrosion resistance of 316L stainless steel in artificial sea water used as a corrosive medium has been investigated. As a result, a passive film and a nanostructured layer were formed on the SMAT-processed 316L stainless steel surface, which considerably increased its corrosion resistance during short-term testing. However, after a long-term exposure to the corrosive medium, the treated sample exhibited deterioration of its corrosion properties because of the micro-strain build-up and the presence of defects in the surface layer. The findings of this work suggest that SMAT can be potentially used for providing short-term corrosion protection to stainless steel objects immersed in aqueous saline media.