TRIBOLOGICAL PERFORMANCE OF MODIFIED FLOCCULENT GRAPHITE AS LUBRICANT ADDITIVES

Abstract

In this research, graphite has been found to have excellent tribological properties as a lubricant additive. To reduce high friction and wear in cylinder liner piston ring friction pairs, modified flocculent graphite have been prepared via chemical technology. The morphology and microstructure of modified flocculent graphite were investigated via SEM, EDS, XRD and IR. In this study, varying concentrations (0.1, 0.5, and 0.9 wt.%) within modified flocculent graphite were dispersed at 350 SN lubricant for Gasoline Engine. Suspension stability of the lubricating oils with modified flocculent graphite and graphite as determined by ultraviolet-visible light (UV-VIS) spectrophotometry. The friction and wear characteristics of lubricants containing materials of modified flocculent graphite were evaluated under reciprocating test conditions to simulate contact. The morphology and microstructure of the friction pair tribofilms produced during frictional contact were investigated via SEM, EDS and a 3D surface profiler. The results show that scratching, pits, furrows and adhesive wear took place, respectively, on the worn surfaces of friction pairs. But, modified flocculent graphite showed excellent friction reducing and anti-wear performance and subsequently has great potential for the application of anti-wear.