Effect of rGO@Fe3O4 on the tribological behavior of biodiesel soot-contaminated polyalphaolefin

Abstract

The biodiesel soot interacts with engine oil and causes the wear of engine parts. In this study, we present the effects of rGO@Fe3O4 on the tribological behavior of the biodiesel soot-contaminated lubricating oil using a UMT-2 multifunction friction tester to ensure active control with respect to the role of biodiesel soot in engine oil. Three-dimensional laser scanning microscopy, field-emission scanning electron microscopy, and Raman spectroscopy were used to analyze the worn surfaces of the lower disc. rGO@Fe3O4 reduced the wear of the GCr15 steel specimens as an additive in the polyalphaolefin-6 base oil containing biodiesel soot. The tribological mechanism can be attributed to the formation of a protecting layer in the presence of rGO@Fe3O4 and the ability of the exfoliated Fe3O4 particles to repair the friction surfaces, enhancing the anti-wear property of polyalphaolefin-6 containing biodiesel soot.