In new video, Engineer Guy Bill Hammack explores shape memory effect and superelasticity


Bill Hammack, a.k.a., Engineer Guy, has released a new video in which he demonstrates the temperature-dependent shape memory of nitinol metal. He explains how “twinning” in the crystal structure of nitinol produces the memory effect and he shows a nitinol-based engine that is powered by temperature differences. He closes the video with a description of superelasticity, a phenomenon related to the memory effect, which he demonstrates with a cardiac stent.