The heat-resistant and tribological mechanism of nano-Fe3O4-reinforced nitrile butadiene rubber

To improve the tribological properties of nitrile butadiene rubber (NBR), nano-Fe3O4 particles with good lubricity were added into the NBR to prepare NBR/nano-Fe3O4 composites. In our experiment, surface microstructure of the composites was observed by JSM-5600LV low-vacuum scanning electron microscope; disposition of nano-Fe3O4 was measured by an energy dispersive x-ray spectrometer; friction and wear condition of the composites were tested by UMT-2MT friction testing machine, and friction condition of the composites were tested for different temperatures by SRV high temperature friction testing machine. The results showed that after adding nano-Fe3O4 particles in NBR, surface of the composites was smoother than NBR due to less defects and the tribological properties were significantly improved. Friction and wear rate of the composites were 300% lower than NBR, and we owe this to the nano-Fe3O4 particles that played a role as solid lubricant on the surface of the composites. Meanwhile, friction coefficient was greatly affected by friction time; when the friction time was more than 10 min, the friction coefficient would become larger and there would be more abrasion; the friction coefficient of the composites was less affected by the temperature with the additional increase in nano-Fe3O4 particles.