Nanoscratch Property of Self-lubricating Ti/MoS2 Nanocoating at Nano-scale Level

Abstract

Nanoscratch test was performed on self-lubricating Ti/MoS2 coating of 99.79 nm thickness prepared by pulse laser deposited technique on Al-13Si substrate. The surface morphology and surface elemental analysis of Ti/MoS2 were studied using Scanning electron microscope integrated with Energy dispersive X-ray spectroscopy. The structural analysis of Ti/MoS2 coating was conducted using X-ray diffraction and Raman spectroscopy. Nanoscratch tests were carried out at low load of 250-1250 µN to examine the deformation and failure behaviour of the coating/substrate system. The results indicate that Ti/MoS2 coating show better adhesion strength at low loads. Also, in-situ scanning probe microscope images of Ti/MoS2 coating shows plastic flow of coating with no debris and cracks on the surface. Thus, the mode of wear mechanism is mainly ductile and abrasive.