Ferroelasticity in magnetorheological elastomers

The combined progress in the fields of magneto-elastic theory, additive manufacturing of soft materials and constitutive modeling has recently increased attention on magneto-mechanics. Departing from the study of classical magnetorheological elastomers (MREs) as bulk material, researchers started to investigate composites featuring permanently magnetic particles (h-MREs) and the stability of magneto-elastic structures. Both directions reach for applications far beyond what can be achieved with mere bulk MREs. Our contribution is inspired by experimental observations and highlights a third avenue to potential applications that is based on the physics that emerge from microstructural multistability of very soft MREs: ferroelasticity. The presentation discusses the underlying processes at microscopic scales by means of analytical considerations and representative numerical simulations. Moreover, we provide a characterization of the material properties of the individual phases and of the external loading conditions under which the effective properties of the composite change from elastic to ferroelastic. In that course we also attempt to connect the observed effects to other domains of (multi-)physics.