Effect of different base oils on the friction behaviour of polycrystalline diamond compact

This study analysed and discussed the friction and wear properties, as well as the interface evolution behaviour of polycrystalline diamond compact (PDC) under various base oils, through conducting friction experiments on PDC/Si₃N₄ with different base oils. The friction and lubrication mechanism of PDC under different base oils were examined using scanning electron microscopy (SEM), x-ray energy dispersive spectrometry (EDS), three-dimensional white light interferometry, and Raman spectroscopy. The results of the study demonstrated that PDC exhibited the best friction and wear performance when lubricated with synthetic oil PAO, followed by castor oil. The inferior performance of paraffin oil can be attributed to its low viscosity, resulting in a lower presence of ions capable of passivating the carbon dangling bond. Consequently, paraffin oil displayed inadequate oxidation stability and increased susceptibility to oil film destruction, ultimately leading to suboptimal friction and wear characteristics. Overall, this study provides valuable insights for industrial applications, aiding in the selection of appropriate base oils as cutting fluids for PDC cutting tools and enhancing the friction and wear properties of PDC.