TRIBOLOGICAL EVALUATION OF PALM OIL-BASED TRIMETHYLOLPROPANE (TMP) LUBRICANT ENHANCED WITH GRAPHENE OXIDE FOR ENGINE OIL APPLICATIONS

Abstract

Palm oil's long molecular fatty acid chains make it a promising candidate for lubricants due to its potential to reduce wear and friction. However, its thin fluid film may sometimes fail to protect contact surfaces. To solve this, an effective additive is required. This study used trimethylolpropane (TMP) as the base lubricant and graphene oxide (GO) as a nano-based additive. The combination's performance was evaluated using a Four-ball tribotester, measuring friction coefficient, wear scar, and surface roughness under various conditions, and compared with synthetic and mineral oils. While the TMP +0.5wt% mixture had a slightly higher friction coefficient than pure TMP, it outperformed both mineral and synthetic oils in friction reduction. Additionally, the TMP+0.5wt% formulation showed significant improvements in surface roughness and wear scar diameter, indicating enhanced surface protection and wear resistance with the inclusion of graphene oxide.