Composites of randomly oriented, chopped carbon fibres in Pb, Ag, Cu, Ni and Co were prepared by powder metallurgical techniques, with fibre contents up to 25% by volume. The most satisfactory method of fabrication is hot-pressing of fibres precoated with metal by electroless deposition. Rates of wear of the composites, measured at room temperature during sliding against tool steel with and without lubrication, are appreciably lower than those of the parent metals. The coefficients of friction are not reduced, however, nor are the wear rates at elevated temperatures (470C). It is concluded that the carbon fibres function by facilitating the development of a strengthened surface layer during sliding. The fibres do not appear to improve the bulk mechanical properties and possible reasons for this are discussed. (Author)
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