In Situ Observation of Extreme Pressure Agents in Elastohydrodynamic Lubrication Oil Film by Micro-Fourier Transform Infrared SpectroscopyⅠ

Achieving high surface brightness and high processability necessitates the development of a lubricant with suitable extreme-pressure (EP) agents to prevent seizures and heat scratches on strip surfaces. Despite its significance, a comprehensive investigation of the mechanisms by which EP agents function within lubricant oils during cold rolling remains insufficient. In this study, we aim to elucidate the effect of EP agents with varying molecular structures on oil film formation, utilizing micro-Fourier transform infrared spectroscopy (micro-FTIR) in conjunction with ball-on-disk testing. The findings reveal that the molecular structure of EP agents significantly impacts oil film formation, attributable to their condensation behaviors at the entry side of the Hertzian contact area and their distinct viscosity characteristics.