Electro-chemical corrosion Behavior of Vegetable oil-Based Engine oil

Abstract

Progressive development of bio-lubricants is the need of the day for replacing petroleum-based lubricants in terms of dependency and degradation. Though the developed lubricants meeting out the properties of petroleum-based lubricants, the hygroscopic nature of the lubricants derived from vegetable oils are suspected to deteriorate the metal surfaces by corrosion. The vegetable oil-based engine oil was formulated via chemical alteration method. The mobility of ions is the key factor for electro-chemical corrosion. In this work we executed the corrosion study of engine oils on metallic coupons through electro-chemistry technique. therefore, vegetable oil-based engine oil and synthetic engine oil were tested in conductivity test using Galvanic cell. In this Galvanic cell, Tetra butyl ammonium perchlorate is used as a catalyst to enhance the mobility of ions in engine oils (electrolyte). The test coupons of ferrous and non-ferrous metal are considered as electrodes. The Tafel plot and impedance curve showed that the corrosion rate for the given current potential is not in the measurable range. Therefore, the electro-chemical corrosion study is not a suitable method to evaluate the corrosion rate of metals on viscous fluids like vegetable oil-based engine oil.