Tribological Study of Nano Fly Ash as Lubrication Oil Additive for AISI 4140 Steel for Automotive Engine Applications

The major concern of the researchers in automotive engine applications is to improve the tribological properties of a material, in order to increase the safety and save energy. Nano additives used with lubricants enhance the anti-wear properties of material when used in different proportions. A variety of nano additives has been used by many researchers to enhance the tribological properties of material, but many aspects of these nano additives and its potential still need to be explored. The effect of nano fly ash as an additive in lubricating oil on alloy steel used in automotive engine applications has to be studied. Fly ash nano particles (FNPS) 0.1% by weight were used as an additive in SAE 10W-30 lubricant and wear behavior of AISI 4140, chromium molybdenum alloy steel was experimented using pin on disc laboratory set up. Three cases were taken under consideration. In Case I, the wear test was conducted in dry conditions. In Case II, SAE 10W-30 lubricant only was used and during Case III, Fly ash nano particles (FNPS) mixed in SAE 10W-30 lubricant were used while conducting the wear tests. The FNPS in SAE 10W-30 lubricant exhibited excellent wear characteristics by decreasing average wear loss and coefficient of friction (COF) remarkably. It was found that in Case II, the coefficient of friction and weight loss percentage decreased by 78% and 62% respectively in comparison to Case I. Where as in Case III, the coefficient of friction and weight loss percentage decreased by 79% and 32% respectively, when compared with Case II. The mechanism of reduced wear was studied using Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS).