A new polyimide matrix composite to improve friction-induced chatter performance through reducing fluctuation in friction force

Stabilizing friction force of polymer composites' wear interfaces during frictional processes is useful to suppress or eliminate the friction-induced chatter and noise behaviors in low velocity. A new Polyimide (PI) matrix composite material composed of Polyimide and MoS2 nano particles was fabricated and tested. The experimental wear tests were conducted to investigate relationship between friction forces, friction-induced chatters and noises under dry and water conditions in low friction velocity. The typical tribological properties of modified composite and some typical mechanical properties were analyzed to reveal the mechanism of MoS2 nano particles on frictional behaviors reduction. The results showed that the transformations and formations of MoS2 tribo-film presented excellent COF reduction on modified PI composite by more than 50%, and also could effectively reduce PI deformations on wear surface which obviously decreased friction forces and their fluctuating amplitudes. These cases endowed the modified PI composite excellent performances on friction-induced chatter and noise reductions compared to the pure PI even though some mechanical properties were weakened. The understanding gained herein is helpful for comprehending the friction-induced chatter reduction of the MoS2 filler on polymer matrix composites and future designing of polymer matrix composites with low friction and good chatter and noise reductions in low friction velocity.