Comparative investigation on the wear and transfer behaviors of carbon fiber reinforced polymer composites under dry sliding and water lubrication

The wear and transfer characteristics of four carbon fiber reinforced polymer composites under distilled-water-lubricated and dry-sliding against stainless steel were comparatively investigated. Scanning electron microscopy (SEM) was utilized to examine composite microstructures and modes of failure. The typical element chemical states of the transfer film on the stainless steel were examined with X-ray photoelectron spectroscopy (XPS). It is found that all the composites hold the lowered friction coefficient and showed much better wear resistance under water lubricated sliding against stainless steel than that under dry sliding. The worn of composites were characterized by plastic deformation, scuffing, micro-cracking, and spalling under both dry- and water lubricated conditions. Such plastic deformation, scuffing, micro-cracking, and spalling, however, are significantly abated under water-lubricated condition. XPS analysis conformed to that the transfer of composites onto the counterpart ring surface is significantly hindered under water lubrication. The transfer film had smaller effect on the tribological behavior of composites under water lubricated condition than that under dry sliding, because under water-lubricated condition the cooling and boundary lubricating effects of the water medium dominated the tribological behavior.