Dispersion stability and wear properties of nano-CeO2 as lubricating oil additives for engines

Abstract

PurposeThe purpose of this paper is to evaluate the dispersion stability and the wear properties of lubricating oil blends added with modified nanometer cerium oxide (CeO2) at high temperature.Design/methodology/approachIn this paper, CeO2 was self-made and it was chemically modified. The dispersion stability of CeO2 in lubricating oil was studied. And the wear test of lubricating oil blends added with modified CeO2 was carried out at high temperature.FindingsThe results showed that CeO2 was successfully modified by oleic acid and stearic acid. The dispersion stability of modified CeO2 in lubricating oil was improved. Adding modified nano-CeO2 with the concentration less than 50 ppm into the lubricating oil can improve the wear properties of friction pairs in different extent. With the increase of the amount of CeO2, the wear properties increased first and then decreased. The lubricating oil blend added with 25 ppm CeO2 has the best wear properties.Originality/valueThe raw material CeO2 in this paper is self-made and its shape and size are well controlled. Research on the addition of nano-CeO2 to the engine low viscosity finished lubricants is lacking. It is of great significance to study the dispersion stability and tribological properties of nano-lubricants under the new background of low viscosity of lubricating oil and close to the real engine working conditions. It has certain significance to promote the development of nano-lubricants for engines.