Tribochemical investigation of tungsten carbide/titanium alloy tribo-couples under aqueous lubrication

The present paper deals with the fundamental understanding on the tribochem ical mechanism of tungsten carbide (WC) coating and titanium alloy tribe-co uples system. The tribological experiments were performed with a Timken-typ e tester. Water containing water-soluble additives was employed as the lubr icating media. The rubbed surfaces of the carbide coating were characterize d with scanning electric microscopy (SEM) and X-ray photoelectron spectrosc opy (XPS), Significant titanium transfer was observed, Results of XPS analy ses show that the interfacial layers formed consist of multiple oxides whic h suggests that oxidative reactions predominate in frictional processes und er aqueous lubrication. It is proposed that the oxide layer is responsible for the tribological behavior because it controls the diffusive and adhesiv e wear. (C) 2000 Elsevier Science S.A. All rights reserved.