The effect of an alumina counterface on friction reduction of CuO/3Y-TZP composite at room temperature

► The addition of CuO into 3Y-TZP reduces friction when sliding against alumina. ► CuO changes of contact conditions. ► CuO reacts with alumina to form CuAlO2 phase. ► CuO increases the wear of alumina and accelerates the formation of an Al-rich surface layer. ► The surface layer reduces friction.