Tribocatalysis and High-Temperature Resistance Characteristics of Magnetically Responsive Lubrication Additives

Lubrication systems constructed with responsive additives exhibit real-time changes in the coefficient of friction (CoF) as the external environment changes to achieve controllable friction. However, the CoF of the currently investigated responsive additives is virtually impossible to modulate in real time. Herein, this work presents a magnetic composite material that exhibits a friction curve with a step change in an applied magnetic field. Importantly, the composites can degrade common contaminants in aqueous solutions through a tribocatalytic effect, exhibiting superior eco-friendly properties. Compared to the base oil at 250°C, the composite lubrication system showed a 19.8% and 66.8% reduction in CoF (0.131 to 0.105) and wear volume (21.1 × 10⁵ µm³ to 7.0 × 10⁵ µm³), respectively. The carbon deposition film and tribofilm formed during the friction process are the dominant factors in high-temperature resistant lubrication. Additionally, the finite element analysis (FEA) results indicate that the applied magnetic field exerts a vertically downward load on the tribopairs, causing an increase in the CoF. This research provides a new strategy for the design of multifunctional nano-additives with high-temperature intelligent lubrication.