The tribological performance analysis of palm olein-based grease lubricants containing copper nanoparticle additive

Abstract

Mineral oil-based lubricants have been widely used for their beneficial properties. However, their environmental impact and toxicity have raised concerns, resulting in a search for sustainable and environmentally friendly alternatives. This study investigates the tribological behavior of palm olein-based grease with copper nanoparticles additive concentrations of 0.25 and 0.50 wt%. The friction and wear tests were conducted using a four-ball tribometer to evaluate the performance of the formulated grease and compare it with commercial mineral grease. The results showed that the palm olein-based grease with a 0.25 wt% copper nanoparticle additive concentration had excellent lubricant performance, with low friction and wear prevention characteristics. This concentration of Cu nanoparticles led to a 35.05% reduction in average friction coefficient (COF), a 32.56% reduction in wear scar diameter (WSD), and a 48.02% reduction in wear volume compared to pure palm olein-based grease.

Tribological and Chemical–Physical Behavior of a Novel Palm Grease Blended with Zinc Oxide and Reduced Graphene Oxide Nano-Additives

“…Despite the promising findings from previous studies, palm oil still suffers from drawbacks such as poor oxidation stability and marginal viscosity values, which limits its application in industry. Therefore, investigators conducted many studies addressing these issues by testing additives on palm oil lubricants [35][36][37][38]. Traditional additives such as zinc dialkyldithiophosphates (ZDDP) have a negative impact on the environment, which involves high contents of toxic sulfur and phosphorous in the blend, the corrosive metallic compounds (such as lead), and tacky solubility of additives in oil [39,40].…”