Fabrication and characterization of composite MoS2-TiO2 coating material

Abstract

Molybdenum disulphide (MoS2) is a popularly used solid lubricant in various applications due to its superior tribological behaviour. However, it possesses poor wear resistance which requires further improvement. In the present study efforts have been made to enhance the tribological properties of pure MoS2 coating film by doping TiO2 nanoparticles as a reinforcement material. The Manganese phosphating is selected as a pre-treatment method to improve the bond strength between coating and substrate. The coating is bonded with the substrate material employing sodium silicate as a binder. The effects of wt. % of TiO2 onto the mechanical properties of composite MoS2-TiO2 coating such as hardness and bond strength have been studied. In addition coating microstructure before and after experimental test was studied using optical microscope and scanning electron microscope. It was also found that with increase in wt. % addition of TiO2 upto 15% into MoS2 base matrix, the hardness of coating increases proportionally. Beyond 15 wt. % addition of TiO2, the coating becomes brittle in nature. This leads to reduction in the scratch resistance.