Tribological Performance of PM400 Bushings in Oscillatory Sliding from 25 to 900°C*
By
Dr. Christopher DellaCorte
Senior Technologist, Tribology and Rotating Machinery
And
Richard A. Manco
Senior Research Technician, Sierra Lobo Corporation at
NASA Glenn Research Center
Cleveland, Ohio
Abstract:
Small bore (6.35mm) bushings, made from NASA PM400 solid lubricant composite, were evaluated in oscillatory sliding contact against a nickel-based superalloy shaft. Tests were conducted in air from 25 to 900°C for extended periods (1 million cycles, +/-15°, 1 Hz) to assess the suitability of PM400 in gas turbine and reciprocating engine exhaust gas path control valve applications. Operating torque and estimated friction was monitored throughout the test duration and wear was measured at the end of test. In general, friction, torque and wear was low. At temperatures above 600°C, bushing dimensional stability was achieved via short duration pre-test furnace exposure heat treatments. Preliminary test results show that bushings made from NASA PM400 are feasible for aerospace and industrial applications.