Effect of machining-induced harden layer on wear resistance of Type316L austenitic stainless steel

In order to clarify the effect of surface hardening layers induced during machining processes such as cutting and grinding on the wear resistance of austenitic stainless steel SUS316L, a surface hardening layer was intentionally induced on SUS316L through lathe cutting. A ball-on-disk friction wear test was then conducted on the hardened SUS316L using an alumina ball with a load of 9.8 N, total sliding distance of approximately 7.9 m to 31 m. The results showed that the samples with a surface hardening layer had a significantly improved volumetric wear rate (up to 37% improvement) compared to those without a hardening layer. To understand the reasons for this improvement, the observation of cross-sectional microstructure, hardness tests, and profile scanning of the test specimens after the wear test were conducted. These observations indicated that plastic deformation suppressed by a harder surface layer on hardened sample, and inducing stable oxidation layer on the worn track which resulted in a reduction in the amount of wear. This suggests that intentionally inducing and retaining a surface hardening layer during manufacturing, especially during machining, can potentially enhance the wear resistance of SUS316L products.