Nanoscratch property of self-lubricating Ti/MoS₂ nanocoating at nanoscale level

Nanoscratch test was performed on self-lubricating Ti/MoS₂ coating of 99.79 nm thickness deposited by pulse laser deposited technique on AI-Si substrate. The surface morphology and surface elemental analysis of Ti/MoS₂ were conducted 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. (author)