Investigation on wear characteristics of a titanium alloy/steel tribo-pair

•The tribo-pair of the Ti alloy/steel is an ideal high-temperature sliding system.•Ti–6.5Al–3.5Mo–1.5Zr–0.3Si alloy is of high elevated-temperature wear resistance.•The protective tribo-layers in the titanium alloy contain more tribo-oxides.

Dry sliding wear tests of a titanium alloy against AISI 52100 steel as a tribo-pair were performed under 50–250 N at 25–600 °C. The wear characteristics of the titanium alloy and the counterface steel were investigated. The results showed that tribo-layers always existed on the worn surfaces of titanium alloy (pins) and steel (disks) in various test conditions. At 25–200 °C, the titanium alloy presented much higher wear rate than the steel. As the temperature increased to 400–600 °C, the wear rate was substantially reduced to very low values for both of the titanium alloy and steel. For titanium alloy (pins), the severe-to-mild wear transition was attributed to the formation of tribo-layers containing tribo-oxides, especially Fe2O3. The tribo-pair of the titanium alloy sliding against AISI 52100 steel was suggested to an ideal sliding system for elevated-temperature applications.