Machinability of Nickel Titanium Shape Memory Alloys: A Review

Shape memory alloys of Nickel Titanium (NiTi) reveal a reversible diffusionless transition between phases, resulting in unique properties and applications. It is widely used in varieties of products; especially in aerospace and medical fields. Yet, these alloys known as hard-to-machine materials owing to their properties of unconventional stress-strain behaviour, high work strain hardening and high ductility. That’s why their machinability is a major issue. The common drawbacks are serious burr formation, rapid tool wear, poor surface quality and high cutting force. This paper puts forward any possibilities to enhance the machining performance through paper reviews from previous researchers. A notable finding is that the machinability issues can be reduced or lessened by changing the cutting parameters and cutting conditions in order to improve the machinability of NiTi alloys.