Effect of lubricating oil temperature on friction coefficient, oil film thickness, and polarizability of transformed layer in friction of ta-CNx film in base oil

Abstract

The low friction mechanism of ta-CNx film is strongly affected by the polarizability of the transformed layer and the oil film thickness. The purpose of this study was to clarify the effect of lubrication temperature change on the polarizability and oil film thickness of the transformed layer and the mechanism of oil film thickness increase with increasing polarizability. Using a reflection spectral friction surface in-situ observation device, a friction test was performed while changing the lubricating oil temperature, and the relationship between each parameter was determined. As a result, the correlation between the polarizability of the structure change layer and the oil film thickness is weak, and the correlation between the product of the polarizability of the structure change layer and the lubricant and the oil film thickness is strong. It was also found that the van der Waals force strongly affected the oil film thickness because the product of polarizability is included in the formula of the van der Waals force.