Friction and wear behavior of nano/ultrafine-grained and heterogeneous ultrafine-grained 18Cr-8Ni austenitic stainless steels

The dry sliding friction and wear behavior of nano/ultrafine-grained (NG/UFG), heterogeneous ultrafine-grained (HUFG), and coarse-grained (CG) austenitic stainless steels was studied. The results revealed that the wear resistance of the samples increased with an increase in hardness under the applied load of 10 N. However, under the applied loads of 20 N and 30 N, the HUFG steel presented the best wear resistance. Analysis of the wear mechanism revealed that the HUFG structure with good comprehensive performances formed a continuous hardened layer early, which did not delaminate and peel off prematurely, thereby effectively resisting the damage of a Si3N4 ball. The epsilon- and alpha'-martensite were generated below the wear surfaces of the NG/UFG, HUFG, and CG samples after wear.