Effects of oxygen ion implantation on wear behavior of NiTi shape memory alloy

The plasma source ion implantation (PSII) technique was employed to modify the near-surface region of NiTi shape memory alloy by ion implantation with oxygen at 45 kV bias and 5 × 1016 ions/cm2 dose. Wear resistance of control and oxygen-implanted NiTi samples was evaluated using fretting wear tests followed by the measurement of wear scar volume. Oxygen ion implantation improved the wear resistance of the NiTi alloy. The wear of NiTi has been described by a modified Archard's equation which incorporates the effect of elasticity and pseudoelasticity on wear resistance in addition to hardness. The relative contribution to wear resistance by elasticity and pseudoelasticity versus hardness is discussed.