Sliding friction and wear behavior of TC11 in aqueous condition

The corrosion wear behavior of a titanium alloy TC11 flat against a high carbon bearing steel ball was investigated in artificial sea water and distilled water with a ball-on-flat configuration, with a reciprocating amplitude of 5 mm at various normal load and frequency. The worn surfaces of TC11 specimens were observed by scanning electron microscopy (SEM). The influences of the load, frequency, and water on the friction coefficient and wear-resistance were analyzed. It is clear that the friction coefficient decreased with an increase in the frequency. As the frequency increased from 5 to 20 Hz the coefficient of friction quickly decreased from 0.40 to 0.27 in distilled water, while it decreased from 0.37 to 0.26 in the artificial sea water. The coefficient of friction was found to decrease with the increase in normal load. However, the reduction in the friction coefficient was influenced more by an increase in frequency than that of load. The results from the SEM and EDS analyses revealed that a lubricating surface was formed on TC11 specimens during wear in artificial sea water which could possibly reduce the friction coefficient. But the wear volume of TC11 in the artificial sea water was always higher than that in the distilled water, which demonstrates that the corrosion of sea water accelerated the wear. The wear mechanism of TC11 in water was related to abrasion wear, whereas it was related to an abrasive wear associated with delamination fatigue in sea water.