FRICTION AND WEAR BEHAVIOUR OF INTERMETALLIC Ni60Ti40 ALLOY MODIFIED WITH ALUMINIUM

Tribological properties of nickel titanium-based alloys were investigated systematically. One binary (Ni60Ti40) and two ternary (Ni58.8Ti39.2Al2, Ni57Ti38Al5) alloys were fabricated using a conventional sintering process. Their friction and wear properties were studied using a reciprocating dry sliding method against 440C steel at temperatures up to 200 degrees C. The results showed that the addition of aluminium reduced the friction coefficient of Ni60Ti40 alloy and increased its wear resistance at all test temperatures. The results obtained were related to microstructure of the alloys and their wear mechanisms. Wear surface of the alloys were characterised mainly by smearing indicating that adhesion was the dominant mechanism governing the friction and wear behaviour of the alloys. At elevated temperature, the area of smearing layer became more visible.