Mechanical Characterisation of PBF-LB Nickel-Rich NiTi tube actuators

Nickel-rich NiTi alloys produced through metal additive manufacturing (AM) allows for the creation of complex shapes with minimal post-processing. The large reversible strain upon heating (Shape memory effect), high power to weight ratio, good functional stability, compact size and lightweight make the NiTi shape memory alloy actuator an interesting candidate for many engineering applications specially in field of aerospace. In the laser-based powder bed fusion (PBF-LB) technique of AM, the process parameters play a crucial effect in the properties and dimensional accuracy of the finished part. In this study, Ni-rich NiTi tubes were manufactured through PBF-LB technique and is further characterized for the actuation force, evolution of microstructure, actuation temperatures (transformation temperatures), hardness, density, size accuracy of finished parts and the effect of heat treatment on the desirable properties of an actuator, thereby providing insights into optimizing these additively manufactured NiTi tube actuators for advanced applications.