Extreme Pressure Properties of 600 N Base Oil Dispersed With Molybdenum Disulphide Nano Particles

Abstract

This work presents the extreme-pressure behavior of 600 N base oil dispersed with MoS2 Nano particles with 1 volume percent of polyisobutylenesuccinamide as dispersant. MoS2 Nano particles were dispersed in 0.05, 1.0 wt. % and tested for Extreme pressure behavior on a 4 ball wear tester using the test method ASTM D 2783. The weld load and load wear index of base oil and oil dispersed with Nano particles are evaluated and compared for improvement. Prior to dispersion, the MoS2 Nano particles are suitably surface modified to make them uniformly disperse in oils. The seizure load, weld load and load wear index of Nano particles dispersed oils have improved remarkably compared to Base oil. Metallographic studies done on the wear balls show that Nano particles get deposited on the worn area preventing the welding of the surfaces and hence higher weld load. The wear scar of bottom there balls are also found to be less for Nano dispersed oils compared to base oil and hence lower load-wear index. reduced by applying extreme pressure (EP) and anti-wear (AW) additives. These tend to be sulphur-chlorine and phosphorous containing compounds designed to react chemically with the metal surfaces, forming easily sheared layers of sulphides, chlorines or phosphide and thereby preventing severe wear and seizure. The advantage of using nano materials in lubricants are 2 fold: one they form a barrier between two mating surfaces thereby preventing wear and secondly the spherical nano particles cat as rollers thereby reducing friction.