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A database tool is developed for archiving and exploring shape memory materials including shape memory alloys (SMAs), superelastic alloys, magnetic SMAs, shape memory polymers, and shape memory ceramics. Over 750 000 data points and their pedigree metadata are extracted and stored into records. Data are handled via a graphical user interface running in a web application. The tool provides interactive menus for the selection of material types, properties, and filters, culminating with a visualization panel. Data are displayed in three forms, consisting of pie charts, 2D scatter plots, and ternary diagrams, all of which provide unique information pertinent to the materials and properties being explored. This database tool is a major stepping stone toward building an information system where an entire continuum of material novices to experts can have an infrastructure to explore and discover these multifunctional materials. [ABSTRACT FROM AUTHOR]

The authors report on a relatively new alloy, Ni54Ti45Hf1, that exhibits strengths more than 40% greater than those of conventional NiTi‐based shape memory alloys − 2.5 GPa in compression and 1.9 GPa in torsion − and retains those strengths during cycling. Furthermore, the superelastic hysteresis is very small and stable with cycling. Aging treatments are used to induce a very high density of Ni4Ti3 precipitates, which impede plasticity during cycling yet do not impart substantial dissipation to the reversibility of the phase transformation. Pairing compression testing with high‐energy synchrotron X‐ray diffraction and aberration‐corrected electron microscopy provides an in‐depth look at the structure‐property relationships of this alloy. Specifically, it is found that a combination of small, untwinned retained martensite laths, and dislocations on the austenite‐martensite interfaces primarily strengthen the alloy as opposed to dislocation networks. Furthermore, some combination of nanoprecipitation and interface dislocations is responsible for the remarkably low mechanical hysteresis exhibited by this material. [ABSTRACT FROM AUTHOR]