Comparative Corrosion Behaviour of Ferrous and Non-ferrous Metals in Bio-lubricant and Bio-diesel Environment

Abstract

Major cause for the deterioration of metals in automotive engine components is due to the corrosive effect of bio-fuels as well as bio-lubricant. This study compares the corrosive behaviour of rapeseed oil bio-lubricant and petroleum lubricant on ferrous and non-ferrous metals. Rapeseed oil bio-lubricant and petroleum lubricant with 10% by volume of rapeseed bio-fuel blend are used for conducting static immersion tests for the period of 2880 h at room temperature. The changes in properties of oils like density and kinematic viscosity were examined for the different metals exposed under bio-lubricant and petroleum lubricant. The corrosion rates of metallic coupons are evaluated by weight loss basis. Degradation of metallic surfaces was characterized by digital camera (visual testing) and SEM. Static immersion test studies show that the non-ferrous metals are more prone to corrosion comparatively ferrous metals exposed in bio-based fuels and lubricants.