Friction and wear properties of PTFE composites filled with different mix materials made of polyimide and graphite.

Polyimide (PI), graphite and copper powder mixed in different proportion filled polytetrafluoroethylene (PTFE) to form a new composite material, respectively in MMU-2 friction and wear testing machine for tribological performance tests, and will wear after sample in JMS-5600 scanning electron microscope observation of friction surface grinding crack and transfer of composite materials, and determine the best proportion. In order to study the influence of test conditions on the tribological properties of materials, the optimal ratio of PTFE matrix composites was tested again by changing test conditions. The results show that polyimide can enhance the wear resistance of PTFE, and increase the strength of the transfer film binding to the dual parts. When the mass fraction of PI is 25%, graphite mass fraction is 5%, and Cu powder mass fraction is 5%, the tribological performance of the material is the best. When the sliding velocity is more than 4.5 m/s, the load is greater than 300 N, the sample surface temperature were greater than 120 °C, composite material has entered into the phase of high temperature and friction, the friction surface creep, transfer film a burning phenomenon. [ABSTRACT FROM AUTHOR]