The coupled effect of thermal and mechanical stabilities of austenite on the wear resistance in a 0.2C–5Mn-1.6Si steel down to cryogenic temperatures

Abstract

The effect of testing temperatures on wear-induced austenite-martensite transformation and the resultant wear resistance in metastable austenite-containing steels remains unclear. This issue is addressed in the current study, wherein the wear behavior of medium Mn steel was studied using a ball-on-disk sliding test at 20 °C, 0 °C, −50 °C, and −120 °C. The results demonstrate that the strain hardening and toughness enhancement produced by metastable austenite in austenite-rich steel greatly reduce wear volume at low temperatures. The dominant wear mechanism thereby changes from grooving and ploughing to cutting compared with martensitic steel. The wear resistance of austenite-rich steel depends significantly on the thermal and mechanical stabilities of metastable austenite. This study provides the basis for the development of novel wear resistant steels with relatively low initial hardness applicated at low temperatures.