Effect of tempering conditions on microstructure evolution and sliding wear behaviour of continuously cooled carbide-free bainitic steel

Microstructural degradation as result of exposure to high temperatures can affect the wear resistance properties of steel. The present study aimed to evaluate the effect of exposing carbide free bainitic steel, a promising material for wear resistance applications, at elevated temperature for varying duration on the microstructure evolution and wear resistance property. A gradual change of wear mechanism from primarily adhesion to combination of abrasion and adhesion to fully abrasion was observed as the severity of tempering was increased. The extent of retained austenite was found to be decreased with increasing acuteness of tempering still good extent of work hardening was obtained where retained austenite was present after being exposed to higher temperature and transformed to martensite during wear.