Strain Glass as Potential Smart Materials

For more than a century, martensite, a micro-sized microstructure, has played a central role in both structural materials (e.g., steels and Ti-alloys) and functional materials (e.g., shape memory alloys). The mechanical and functional properties of these materials come from micron-sized martensite and martensitic transformation, and the manipulation of which by temperature, stress, and magnetic field can lead to effects of technologically importance, such as shape memory effect and superelasticity. Contrasting with the martensite materials, over the recent 15 years more and more evidence has been found and knowledge accumulated on the existence of a new class of martensite-derived materials called “strain glass”, which is characterized by nano-sized martensite domains and a sluggish strain glass transition. The manipulation of these nano-domains by temperature and external field can lead to novel effects not found in conventional martensitic materials, such as nearly hysteresis-free superelasticity, giant magnetostriction, Invar and Elinvar effect. In this talk we shall talk about the state-of-the-art of strain glass studies and its potential applications as novel smart structural materials.