Influence of Oxynitriding on Antifriction Properties of Ti–6Al–4V Titanium Alloy

The wear resistance of a plate–screw tribo pair used to fix bone fractures was investigated using the pin-on-plate configuration under conditions of dry friction and friction in Ringer’s solution. The nitrided and oxynitrided plates of Ti–6Al–4V titanium alloy in friction pairs with Fe–18Cr–10Ni–1Ti stainless steel were used. It was determined that under dry friction conditions, regardless of load, the nitrided Ti–6Al–4V titanium alloy provides a lower friction coefficient than the oxynitrided one; friction is implemented according to the adhesive wear mechanism. The use of Ringer’s solution during friction tests leads to an adhesive–oxidative wear mechanism that decreases the friction coefficient in friction pairs of nitrided (oxynitrided) Ti–6Al–4V titanium alloy–Fe–18Cr–10Ni–1Ti stainless steel. In addition, the oxidative portion in the wear mechanism for an oxynitrided surface is greater, which decreases the adhesive wear in such a friction pair.