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Top1. Introduction
The tribological behaviour of the carbon fibre reinforced composites is believed to be influenced by the nature of matrix, microstructure and fibre architecture of the composites. Wear of components under oscillatory relative motion (either linear or torsional) with small amplitudes of displacement is termed as low amplitude reciprocating wear. Such short amplitude reciprocating sliding between contacting surfaces for a large number of cycles involves fatigue and is also termed as fretting wear. It has been shown that micro-movements involved in the process of reciprocating sliding motion are fundamentally associated with Hertzian contact subjected to a tangential force (Mindlin, 1949). One of the special characteristics of fretting is the prolonged retention of wear debris between the sliding surfaces, when amplitude of sliding is relatively small. It has been shown that such accumulation of debris can cause depressions on the surfaces by deformation (Colombie, Berthier, Floquet, Vincent, & Godet, 1984) due to the development of large contact stresses. Moreover, the temperature may affect the process of fretting in two ways: (12) corrosion and oxidation rates usually increase with temperature; and (ii) the mechanical properties of materials usually change with temperature.
Reinforced polymer based composites are frequently used to make components such as bearing’s outer ring and housing, wire ropes, electrical switchgears, multiplayer leaf springs, palliatives, spline couplings, flanges, seals, riveted and pinned joints (Ohmae, Kobayashi, & Tsukizoe, 1974; Bill, 1985; Jocobs, Friedrich, & Schulte, 1991), where fretting wear is commonly observed. A survey of the literature (Chivers & Gordelier, 1984; Vishwanath & Rao, 1991; Sabota & Holy, 2000; Bijwe, Indumathi, & Ghosh, 2002; Bijwe, Indumathi, Satapathy, & Ghosh, 2002; Bijwe & Rattan, 2006; Xiang & Chuanjin, 2006; Rattan & Fahim, 2007; Shangguan & Cheng, 2007; Li & Cheng, 2008) suggests that research on the tribological behaviour of the continuous fibre reinforced composites has received significant attention. On account of their high strength and elastic modulus, corrosion resistance, good friction and wear properties and low thermal expansion, carbon fibres are widely used as fillers in advanced composite materials (Okabe & Takeda, 2002). However, limited information is available about the performance of carbon fibre reinforced composites with phenolic and epoxy matrices. In the present study, the response of two dimensionally (2D) reinforced carbon-fibre reinforced composites having different phenolic or epoxy matrices to reciprocating wear tests under two different test loads at either room temperature or 250 oC have been compared. These tests could not be carried out at higher temperatures such as 500 oC, because the rates of vaporization of phenolic and epoxy matrices have been found to be accelerated to an extent that damage by wear becomes less significant.