Wear Performance of Ultra-Performance Engineering Polymers at High PVs 2002-01-0600
Previous tribology studies on ultra-performance engineering polymers, which include polyetheretherketone, (PEEK), polyamideimide (PAI), and polyimide (PI), have focused on pressure and velocity (PV) conditions lower than those typically seen in automotive transmissions. Thrust washers, seal rings and bearings typically endure severe PV conditions. Although this environment is normally lubricated, actual lubrication conditions can vary and the best polymeric materials will be able to handle a loss of lubrication without failure. This study investigated the ultra-performance class of engineering polymers at high PV conditions (50,000-100,000 ft-lb/in2min), under high velocities (up to 800 ft/min), using the ASTM D 3702 thrust washer test specimen rotating against C1018 steel. Tests were done without external lubrication in order to evaluate the performance of the polymer compounds under extreme conditions.
In general, all the materials performed well under low velocity and low PV test conditions as one would expect. When test velocities were increased, a differentiation of the wear resistant properties of the material became evident. Fair performance was apparent in the PEEK compounds. Better wear resistant characteristics were achieved by the polyimide and polyamideimide compounds, with one of the polyamideimide compounds showing excellent wear properties over the entire test regime.