Effect Of Tempering On Tribological Properties Of 13cr Martensitic Stainless Steel And Alumina Material Pair In Dry Sliding

This present study seeks to understand tribological properties of 13Cr martensitic stainless steel (MSS) in austenitizing and tempering conditions (300, 550, and 700 degrees C). A ball-on-plate configuration with an alumina ball as the counterface was employed for dry sliding experiments. Complementary analytical techniques such as 3D optical profilometry, optical microscopy, scanning electron microscopy/energy-dispersive spectroscopy, and microhardness measurements were used to elucidate the operating wear mechanism. The results showed that the coefficient of friction (COF), wear rate, and wear mechanism changed significantly with tempering temperature. Austenitized and 300 degrees C tempering condition exhibited stable COF variations with time, whereas fluctuating and increasing COFs with time were observed in 550 and 700 degrees C tempering conditions, respectively. Wear resistance for the tempering condition was lower than that for the austenitizing condition, with the least wear resistance for the 550 degrees C tempering condition. The wear resistance of the alumina ball also followed the same trend as for 13Cr MSS. The least wear resistance of the counterface material was observed against the 550 degrees C tempering condition. These observations were attributed to the (a) formation of large amount of nanosized carbides and (b) embedment of the counterface material during sliding. The austenitizing and 300 degrees C tempering conditions showed abrasive plus mild oxidation wear mechanism, whereas tempering at 550 and 700 degrees C showed delamination plus the presence of adhesion traces and a compacted tribolayer plus severe oxidational wear mechanism, respectively. The present results clearly highlight the changes in wear mechanism of 13Cr MSS against the counterface alumina ball with the developed microstructural changes during tempering treatments.