Dry Tribological Property of Carbon/polytetrafluoroethylene Hybrid Fabric Reinforced Epoxy Composite

Carbon/polytetrafluoroethylene (CF/PTFE) hybrid fabric reinforced epoxy resin self-lubricating composite was fabricated. Tribological properties of the composites against 45 steel with a ring-on-ring configuration in dry sliding were studied. Influences of fabric, friction heat, load, sliding velocity on composite tribological properties were discussed. Infrared thermographer, thermocouple and cooling air were used to survey and control the friction pair temperature. Worn surface of composite and its counterpart were investigated with laser scanning confocal microscope and scanning electronic microscope equipped with energy disperse spectroscopy. Test results show that composite reinforced by hybrid fabric had better friction and wear property than composite reinforced by carbon fabric. The operating parameters, i.e. friction pair temperature, load and sliding velocity had postive influence on friction and wear property. Transfer film of PTFE was observed on the worn 45 steel surface. Wear mechanism of the composite was fatigue. Tribological property of composite depended on the temperature of friction pair. Adhesive wear and oxidation wear occurred when the composite heated up to distortion temperature. Plastic flow of the resin matrix occurred and friction force increased. Hybrid fiber configuration had influence on the friction and wear property. The PTFE transfer film was damaged by massive broken carbon fibers and abrasive wear prevailed. Solid lubricant in wear debris played the major role in reducing friction.