Recent Progress in Shape Memory Alloys and Additive Manufacturing

This chapter aims to review the current progress on the application of additive manufacturing (AM) to nickel-titanium (NiTi) shape memory alloys (SMAs). These materials are unique as they have properties of shape memory that aids transformation between the austenitic and martensitic phases, and they returns to their original form when heated. AM technologies like laser powder bed fusion (LPBF) have added value to the fabrication of complex geometric features and microstructures tailored for different uses, especially in biomedical engineering. This chapter addresses the advantages of AM in the fabrication of SMA components with enhanced mechanical characteristics and minimal material wastage compared to conventional production techniques. There is a focus on the possibility of producing stents and orthodontic wires which utilise with the shape memory effect making them useful for maintaining a patient's health without invasive operations. In addition the present review discusses issues pertaining to the processing of NiTi SMAs, particularly phase stability and defect characteristics during AM.