Electrostatically Self‐Assembled Magnetic Nanoparticles for High‐Temperature Resistant and Friction‐Controlled Lubrication System

Abstract

Magnetic‐responsive surfactants are considered promising smart lubricating materials due to their significant stimulation response to applied magnetic fields. In this study, four magneto‐responsive surfactants are successfully fabricated and encapsulated on the surface of molybdenum disulfide nanosheets (MoS2@C18H37N+(CH3)3[XCl3Br]−, X = Fe, Ce, Gd, and Ho) as base‐oil components using electrostatic self‐assembly, thereby constructing a multi‐functional magnetic lubrication system (MoS2@STAX). Magnetorheological measurements confirm the remarkable responsiveness of MoS2@STACe lubricants at high shear rates and applied magnetic fields, which is further corroborated by the constant proximity of the magnet. The formation of dense carbon and tribo‐chemical films between the friction interfaces at elevated temperatures is the primary factor contributing to the significant reduction in frictional wear. Notably, the magnetic lubricant demonstrates a pronounced response behavior when subjected to an applied magnetic field in the ceramic tribopair, even at lower magnetic fields. This work presents concepts for the development of high‐temperature resistant and tunable lubrication additives by designing the material structure and controlling the magnetic stimulation.