Tribological Behavior of Nanocrystalline Layer on 316L Stainless Steel Subjected to Surface Mechanical Rolling Treatment under Corrosion Environment

A gradient nanostructured layer was fabricated on 316L austenitic stainless steel by means of surface mechanical rolling treatment (SMRT) technology. The microstructure and mechanical properties of the surface layer were studied by transmission electron microscopy, nanoindentation tester. And on this basis, this article focused on the tribological behavior of 316L before and after SMRT in 1 mol/L HCl solution, and the pure water environment was taken as the reference group. The results showed that, a gradient nanocrystalline layer with a thickness of 200 μm was formed after SMRT processing. The surface hardening layer exceeded 1.5 mm in thickness. The surface microhardness of surface hardening layer was twice as much as that of the base metal. The surface subjected to SMRT greatly alleviated wear. Compared with the base metal, SMRT surface was effective in reducing friction under the corrosive medium than that under the pure water environment, and it exhibited excellent corrosion resistance. The wear mechanisms varied from abrasive wear and fatigue wear accompanied by severe delamination before treatment to mild fatigue wear. Therefore, the nanostructured layer of 316L subjected to SMRT is a good candidate for application.