Transient Thermal Investigation of Dry Sliding Friction at a Polymer-Metal Interface

Polymers for tribological applications in machines offer the advantages of simple designs, reduced manufacturing complexity and lower maintenance costs. However, polymers are far more sensitive to friction-generated temperature than are metals or ceramics. Some typical tribological polymers are being evaluated in dry sliding by a thermo tribometer that uses a thrust washer configuration [1,2]. The polymer is pressed against and slides on a ring-shaped, thermocouple-instrumented metal anvil mounted on a torque cell thus providing for simultaneous measurement of friction and temperature. Previously reported finite element estimates of temperature distribution in the polymer-metal couple have been used to guide the design of and testing with the thermo tribometer [3]. Reported here are experimental results of friction and temperature rise for three polymers (acetal, nylon 6/6, UHMWPE) sliding against metal anvils (stainless steel, aluminum) with different thermal diffusivities. Results were obtained with normal pressures of 93–465kPa and sliding speeds of 0.81–4.06 m/s during the first 300 seconds of sliding.