Anti-corrosion and corrosive wear properties of AISI 316L stainless steel with surface nanocrystallization by surface mechanical rolling treatment

Abstract

In this work, surface mechanical rolling treatment (SMRT) was adopted to obtain the gradient nanostructured (GNS) layer on AISI 316L stainless steel (SS) surface. To evaluate the effect of the GNS, anti-corrosion and corrosive wear tests of the SMRT sample were conducted in pure water and corrosive medium in comparison with a unSMRT (i.e., coarse-grained 316L SS). The corrosion behaviors, tribological properties, damage mechanism as well as relation of pitting and delamination, have been investigated to clarify their synergetic effects and failure mechanism. The results show that, the GNS of 316L SS has poor corrosion resistance due to initiation in local of stress corrosion crack (SCC). However, in comparison with the unSMRT sample, the pitting resistance of 316L SS after SMRT is significantly enhanced. For both samples, the wear loss by delamination is obviously accelerated by corrosion in the friction process. The tribo-corrosion resistance is markedly enhanced with the GNS layer relative to the unSMRT sample, the GNS layer can effectively inhibit the formation of delamination in the corrosive environment, and can also mitigate the abrasive wear in the water lubrication condition, due to the beneficial combination of superfine nanocrystalline structure and high hardness of the GNS layer.