Study Tribological Properties of MoDTC and Its Interactions With Metal Detergents

Abstract

Recently, the synergistic tribological properties between molybdenum dialkyldithiocarbamate (MoDTC) and metal detergents have been the focus of significant attention due to the high requirements of engine oil. In this study, an SRV tribometer and four-ball machine were used to study the tribological performance of MoDTC combined with three types of metal detergents with different base numbers. Meanwhile, the detergency of the three metal detergents was also investigated using the hot tube test and crankcase simulation test. The results showed that (i) a high-based detergent possessed an excellent detergency performance compared with that of low-based detergents. (ii) The tribological properties of the base oil with a content of 0.75% MoDTC were superior to those of other contents at elevated temperatures. (iii) The metal detergents with a higher base number showed the best thermal stability, detergency performance, and anti-wear performance among the three types of metal detergents. The anti-wear mechanism was that the synergistic action of active elements in MoDTC and metal detergents promoted the generation of a tribological film.