Tribological properties of a tightly woven carbon-carbon composite

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2005
Karaveli, Keriman
Tribological properties of a tightly woven Carbon/Carbon (C/C) composite were assessed experimentally in accord with the ASTM pin on disk technique. The C/C composite used in this study was a commercial material (K-Karb) obtained in a panel form. The composite consists of graphite fiber reinforced graphite matrix developed for aerospace applications. The fiber reinforcement was in a plain weave woven fabric form. The tests were conducted by sliding zirconia ball against the C/C composite. The friction coefficient and wear rate were determined as functions of applied load, sliding speed, sliding distance and lubrication in ambient laboratory conditions. Mean friction coefficient of the composite was 0.135 æ when tested at ambient atmosphere and 0.113 æ in lubricated environment at a load of 5 N, sliding speed of 0.5 cm/s, and sliding distance of 100 m. The wear volumes determined from surface profile traces obtained on the wear tracks after completion of the tests were used for calculations of the specific wear rates. The specific wear rates of the composite were 0.754 x 10-4 mm3/N.m at ambient atmosphere and 0.437 x 10-4 mm3/N.m in lubricated environment at the load of 5 N, sliding speed of 0.5 cm/s, and sliding distance of 100 m. The specific wear rate of the composite decreased with increasing sliding distance, sliding speed, applied load and also, decreased in lubricated environment. Keywords: C/C composite, tribology, friction, wear, lubricant.

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Citation Formats
K. Karaveli, “Tribological properties of a tightly woven carbon-carbon composite,” M.S. - Master of Science, Middle East Technical University, 2005.