Shape Memory Zirconia: Shape Memory, Superelasticity, and Electric Field-Activated Shape Memory at Small Scales

Whereas zirconia ceramics are widely known for their propensity to crack during their martensitic tetragonal-to-monoclinic transformation, the past decade has seen a surge of activity on small scale samples in which cracking can be avoided. This talk will provide an overview of such studies, illustrating various compositions and structures in which small single- and oligo-crystalline specimens survive the transformation. The resulting shape memory and superelastic properties of zirconia present unique opporunities that may not be achieveable with other shape memory materials, such as shape actuation at very high stresses and temperatures. Finally, our latest work shows how the electrical susceptibility of zirconia enables shape memory triggered directly by an electric field in a paraelectric material for the first time. This demonstration provides a new bridge between the fields of shape memory and electroceramics with many open questions.