Tribological results of PEEK nanocomposites in dry sliding against 440C in various gas environments

This case study reports on a recent survey of filled polyetheretherketone composites. A wide variety of available nanoparticles and microparticles were used during this exploratory activity. The friction coefficients ranged from below mu = 0.05 to over mu = 0.60; the wear rates varied from 10(-4) to 10(-7) mm(3)/(N m). The tests were run against 440C stainless steel counterfaces in open laboratory air with approximately 45% RH, a dry nitrogen environment with less than 0.5% RH, and unfilled PEEK was cycled between ambient air and high vacuum (10(-6) Torr). The open (with edge sites) and closed (without edge sites) structures of the solid lubricant particles did not demonstrate a clear environmental dependence, while the PEEK showed a very low friction coefficient and wear rate in dry and vacuum environments. (C) 2007 Published by Elsevier B.V.