PERTANIKA JOURNAL OF SCIENCE AND TECHNOLOGY

In this study, palm olein-based grease with a micro-molybdenum disulfide (MoS₂) additive has been developed. The grease was prepared using various MoS₂ concentrations to investigate the role of additives in improving grease performance. A four-ball tribological test was conducted to investigate the surface morphology, wear depth, and volume loss of the steel ball. The results indicated that the MoS₂ additive reduced the coefficient of friction and wear scar diameter compared to pure palm olein grease. The value of 0.5 wt.% was considered the optimum value, reflecting the best grease performance indicated by low friction coefficient, wear diameter, wear depth, and volume loss. Elemental analysis revealed that the MoS₂ additive was deposited onto the wear tracks, improving the surface protection. Thus, this additive was found to have a good potential for improving palm olein-based grease.

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