Reinforced polymer-matrix composites are widely used under sliding contact conditions in various boating and automotive applications. In this paper, the friction and wear of bulk epoxy and carbon filler reinforced epoxy composites have been investigated using a pin-on-disc tribometer. The effect of different fillers on the tribological behavior of an epoxy has been studied using treated and untreated carbon nanotubes, graphite, and a mixture of graphite and carbon nanotubes. Filler addition greatly enhances the tribological properties of the epoxy resin, by reducing the friction coefficient and the wear rate. In addition, it was found that the treated carbon nanotubes/epoxy composites have the best tribological behavior. Moreover, a correlation between contact temperature and friction coefficient is reported. Finally, the wear mechanisms were determined by scanning electronic microscopy.

The olive pomace erosion wear behavior of carbon fiber-reinforced epoxy composite (epoxy/CF) has been analyzed. A tribological test was carried out using an in house centrifugal testing setup in order to simulate the environment in olive oil extraction procedure. The environment is composed from a pomace-to-water ratio 70/30. The erosion wear-rate of this composite has been studied at different impact angles (45 deg and 90 deg) and at different impact velocities (200, 1200, 1500, and 2000 rpm). It was demonstrated that both the impact angle and the impact velocity have a significant effect on the carbon fiber-reinforced epoxy composite erosive wear-rate. The main findings reveal an erosive wear characterized by brittle damage; in fact, micro-cracks at the surfaces and sub-surfaces were found. The damage surfaces were marked by fragmented fibers.

In this study, the wetting time measurement of five weathering plates, which have three types of chamfered edges, were carried out for clarifying the superiority of drainage performance. The wetting state on steel surface was judged by measuring the electrical resistance at a center point near the plate edge. The inclination of all specimens was set to 2 % in this wetting time measurement. The protective rust (about 70 μm thickness) was generated all over the surfaces of specimens by the outdoor exposure test. From the experimental results, the linear-chamfered edges could shorten the average wetting time by 14~28 % than the non-chamfered edge, because the water-drops attached to the edges drip more easily. On upper surface, the drainage performance will be significantly influenced by the cutting size of chamfered edges.

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