Investigation of physicochemical and tribological properties of TiO2 nano-lubricant oil of different concentrations
Nano-lubricants provide enhanced tribological properties in several applications like machines and engines. The presence of nanoparticles in the lubricating oil effects its wear, friction, thermal, chemical and physical properties in many ways. This article reports effect of TiO2 nanoparticles suspended in servo system lubricating oil prepared by sonication process without adding any surfactant. Four different volume concentrations (0.2%, 0.4%, 0.6% and 0.8%) of TiO2 nanoparticles in the base lubricating oil are used for analysis. Calorific value, flash point, viscosity are the physicochemical properties of the TiO2 nano-lubricant investigated at different Volume Concentrations (VC). Wear scar diameter and coefficient of friction are the tribological properties analyzed for the prepared nano-lubricant at different VCs. Calorific value and flash point of the nano-lubricant was found to be decreasing with increasing VCs compared to base lubricant oil. Viscosity, on the other hand was almost same as the base lubricant oil for the proposed VCs. Wear scar diameter and friction coefficient was found to increase with increase in VC of TiO2 nanoparticles in the lubricant oil. It is concluded that, to obtain better results agglomeration of nanoparticles has to be avoided which can be achieved with the use of surfactant.