Tribological properties and thermomechanical analysis of unsaturated polyester fabric composite in oscillating line-contact sliding

• Thermoset polyester fabric with highly recoverable elastic deformation.
• Instable frictional regime corresponding to onset of curing.
• Stable friction regime by thermally controlled sliding of PTFE solid lubricant.
• Interpretation of maximum polymer surface temperature for thermosets.

The friction and wear properties of a composite containing unsaturated polyester resin with polyester fiber fabric reinforcement and internal PTFE lubricants are described under reciprocating dry sliding in a cylinder-on-plate contact against steel. By taking into account the deformation, creep, thermal expansion and strain recovery, on-line measurements for diameter reduction by wear are in agreement with post-mortem weight loss measurements. However, it is most important to consider the effects of the maximum polymer surface temperatures. The sliding properties are controlled by mechanical shear and plasticization of the PTFE lubricants under mild sliding conditions with a transition into instable sliding at 75 °C correlating with curing of the matrix, and stable sliding at temperatures of 120 °C corresponding to thermally-controlled sliding of PTFE.