For the purpose of improving tribological properties of FRP sliding pads, an investigation was made on the friction and wear properties of glass fibre reinforced vinylester composite materials with various kinds of fillers. Three types of composites with fillers (pitch based carbon fabric mat: RCM, pitch based short carbon fibre and polyester felt: RPC, and graphite particles and polyester felt: RPG) and a vinylester resin for a comparison specimen were prepared in this experiment. It was also surveyed that the surface roughness of the steel counterface was influenced by the fillers. The tribological properties of these composites were determined with a reciprocating-slider frictional testing machine under a dry condition. Experimental results showed that the coefficient of friction and abrasion loss of these composites reduced in comparison with those of a vinylester resin. RPC presented lower frictional coefficient, particularly. The specimen for maximum wear resistance was RPC during short distance, and RPG for later. The steel surface roughness to RPG was unchanged. On the other hand, the surface roughness value increased with both RPC and RCM at far sliding distance, because carbon fibre injured a steel surface.
