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Effect of load, area of contact, and contact stress on the tribological properties of polyimide bonded graphite fluoride filmsA pin-on-disk type of friction and wear apparatus was used to study the effect of load, contact stress and rider area of contact on the friction and wear properties of polyimide-bonded graphite fluoride films. Different rider area contacts were obtained by initially generating flats (with areas of 0.0035, 0.0071, 0.0145, and 0.0240 cm) on 0.476-cm radius hemispherically-tipped riders. Different projected contact stresses were obtained by applying loads of 2.5-to 58.8-N to the flats. Two film wear mechanisms were observed. The first was found to be a linear function of contact stress and was independent of rider area of contact. The second was found to increase exponentially as the stress increased. The second also appeared to be a function of rider contact area. Wear equations for each mechanism were empirically derived from the experimental data. In general, friction coefficients increased with increasing rider contact area and with sliding duration. This was related to the build-up of thick rider transfer films.
Document ID
19820043538
Document Type
Conference Proceedings
Authors
Fusaro, R. L. (NASA Lewis Research Center Cleveland, OH, United States)
Date Acquired
August 10, 2013
Publication Date
January 1, 1981
Subject Category
MECHANICAL ENGINEERING
Meeting Information
In: Wear of materials 1981(San Francisco, CA)
Distribution Limits
Public
Copyright
Other