Transfer layer formation in MoS2/hydroxypropyl methylcellulose composite

Understanding the mechanism of transfer layer formation in tribological systems is important as it greatly influences the wear behavior of polymer based composites. The proposed study analyzes the formation of transfer layers on the counter body surface of a tribological system containing an MoS2/biopolymer (hydroxypropyl methylcellulose) composite thin film with the aim of improving the coverage and, hence, the lubrication effect of the layers. The role of the thin film is also investigated from the aspect of the third-body approach. The formation mechanism of the transfer layer is studied by adding different amounts of MoS2. Field emission scanning electron microscopy with energy dispersive spectrometry has been used for the surface structural and elemental analyses of the transfer layer. Raman spectroscopy is used to analyze structures of the thin film as well as the transfer layer. An appropriate amount of MoS2, as an additive, was found to improve the ability of the third body to remain in the internal zone of the contact area between friction pairs rather than accumulating in adjacent zones. Addition of MoS2 was, thus, found to enhance the formation and development of transfer layers thereby strengthening their anti-wear and lubrication properties.