A Comparative Study of Additively Manufactured Nickle Titanium (NiTi) Shape Memory Alloy (SMA)

Nickel titanium (NiTi) belongs to the class of Shape Memory Alloy (SMA) and has a memory capability to retain its original shape when subjected to stress or temperature changes. It undergoes solid to solid state phase transformations from an austenite to martensite phase which corresponds to the functional properties of pseudo elasticity (PE) and shape memory effects (SME). These indicate a strong coupling effect of NiTi in response to stress and temperature changes. These properties esteemed NiTi as an excellent candidate for many design applications in automotive, aerospace, robotic and biomedical industry. However, potential applications of NiTi are hindered by the conventional manufacturing methods that are limited to simple geometries. Therefore, advances in Additive Manufacturing (AM) techniques can simplify the process by fabricating NiTi parts with complex geometry and enhanced the mechanical aspects of NiTi. A review on additively manufactured NiTi is provided in this paper. This paper also reviews affecting parameters of additively manufactured NiTi. Besides that, a case study on NiTi fabrication through directed energy deposition (DED), selective laser melting (SLM) and electron beam melting (EBM) are briefly explained in this paper. The main aim of this paper is to provides a fundamental knowledge on additively manufactured NiTi and to give readers a better understanding on the perspectives of material properties.