Effect of magnetic field on tribological performances of two lubricating oils with phosphorus‐containing additives

Abstract

Abstract The influence of magnetic field on the tribological properties of 150SN mineral oil and the oils formulated with tricresyl phosphate or ammonium thiophosphate was evaluated on a modified 4‐ball tribo‐tester. The influencing mechanisms were discussed from the viewpoint of physical effect and chemical effect. The results indicated that the applied magnetic field improved the anti‐wear ability of the neat mineral oil and T306‐doped oils but impaired that of T307‐doped oils. The friction‐reducing capacity of the tested oils was undermined by the magnetic field. The atomic concentrations of the functional elements identified in T306 or T307 under magnetic field were higher or lower than those without magnetic impact, respectively. The magnetic force between steel balls and tribo‐diffusion of the functional elements contained in T306 or T307 into the substrate induced by magnetism was inferred to impair the friction‐reducing performances of the formulated oils.