Experimental Study on Enhancement in the Tribological Behaviour of Military Grade Lubricant Using Titanium Dioxide Nanoadditives for Aerospace Applications

ABSTRACT The coefficient of friction of low carbon chromium alloy steel with military grade lubricant was high, resulting in increased heat generation and temperature rise of the lubricant in the aircraft power transmission units such as engine gearbox, accessory gearbox and so on. To address this, the current research proposes the addition of TiO 2 nanoparticles to MIL grade lubricant as an additive to enhance the tribological performance. In this experimental study, TiO 2 nanolubricant was prepared using various surfactants for better suspension of TiO 2 nanoparticles, and properties were evaluated for both base lubricant and nanolubricant. The tribological experiments were conducted using a four ball tester, a shear stability tester and a reichert tester. In a four ball test, TiO 2 nanolubricant resulted in a 27.3% reduction in wear scar diameter by the addition of TiO 2 nanoparticles to the base lubricant. In a shear stability test, TiO 2 nanolubricant showed 80% better shear stability than the base lubricant. In the reichert test, the coefficient of friction was reduced by 13% with the TiO 2 nanolubricant. The experimental findings demonstrated that the TiO 2 nanoparticles, as an additive to a military grade lubricant, have superior tribological properties for aerospace applications.