Enhanced tribological properties of bismaleimides filled with aligned graphene nanosheets coated with Fe₃O₄ nanorods

Hybrid particles composed of reduced graphene oxide sheets (GNSs) coated with Fe₃O₄ nanorods (GNS-Fe₃O₄) were synthesized through a facile coprecipitation route. Bismaleimide (BMI) composites were then prepared with the aligned GNS-Fe₃O₄ hybrid particles by a casting method, and the effect of the GNS-Fe₃O₄ hybrid particles on the mechanical and tribological properties of the composites was investigated. It was found that the BMI composites with the aligned GNS-Fe₃O₄ exhibited thermal stability, as well as excellent mechanical and tribological properties, such as friction coefficients as low as 0.07 with 0.6 wt% GNS-Fe₃O₄. This is mainly due to the fact that the aligned GNS-Fe₃O₄, with its layered structure, can effectively reduce the friction coefficient due to the good synergy between the graphene and Fe₃O₄ during the wear process. The obtained results indicate that the magnetic alignment of GNS-Fe₃O₄ is an effective method for greatly improving the friction and wear properties of resin-based composites.