Temperature dependent sliding wear behaviour of Stellite 6 alloy

Abstract

The present work investigates the frictional and sliding wear characteristics of cobalt-based alloy, Stellite 6 at room temperature (RT), 150 °C, and 300 °C. Wear tests were performed using a ball on plate reciprocating tribometer with a tungsten carbide ball as a counter surface. Scanning electron microscopy (SEM) and Raman spectroscopy techniques were used to investigate worn surface morphology and chemical characteristics, respectively. The wear test results clearly indicate that the specific wear rate increased with increasing temperature. Abrasion, oxidation, and delamination wear mechanisms were observed as predominant at higher temperatures. The formation of CoO and Co3O4 phases were evident from the Raman spectroscopy analysis, which is responsible for the reduction of friction, particularly on the samples tested at elevated temperatures. Formation and removal of the tribo-oxide layers at higher temperatures are responsible for increased wear rate as compared to the sample tested at room temperature. The results demonstrate a strong influence of temperature on the wear and friction characteristics of the alloy.