Effect of heating of test pin above ambient temperatures on tribological behavior of two-phase and three-phase polystyrene composites

Abstract

The tribological behavior of the sliding surfaces is dependent on the frictional heating. Surface and near surface temperatures may become high enough to cause changes in structure and properties of the sliding surfaces. It can also cause oxidation and even melting. Wear and frictional behavior of materials above ambient (25°C) conditions would become critical for polymers as the operating temperature bands of polymers are always limited. In the present study, tribological studies on two-phase and three-phase polystyrene composites at temperatures of 45 and 60°C have been reported. It is found that with increase in temperature the wear rate increases, whereas the friction coefficient decreases. Polymer–ceramic composite exhibited higher friction coefficient than other composites. At temperature of 45°C, the wear rate of the neat polymer increases exponentially whereas at 60°C it decreased. However, addition of fillers into polystyrene brought in drastic reduction in the wear rate of polymer composites. Scanning electron microscopic pictures revealed melting, flowing, and glazing after wear test. Higher pressure velocity resulted in higher wear coefficient.