Demonstration of shape memory and superelastic effects of nitinol alloys

Abstract

One of the outcomes of the course entitled: Experimental Methods in Orthopaedic Biomechanics is for mechanical and bioengineering undergraduate and graduate students to learn the design and implementation of Nitinol (Nickel-titanium, NiTi) alloys. This is achieved by conducting two experiments to observe the shape memory and superelastic effects of NiTi alloys. The superelastic effect exhibits itself when a relatively high mechanical load is applied to the material at relatively high temperatures. In this condition the material recovers relatively high levels of deformation upon unloading. The shape memory effect is the material behavior after permanent deformation in response to temperature changes which leads to shape recovery. NiTi wires were tested in both experiments.