Harnessing magneto-mechanical coupling to tailor structural transformations in soft composites

Materials with shape-shifting and morphing capabilities are crucial for applications such as soft robotics and deployable devices. Here, we focus on the structural transformations associated with the onset of instability in soft composites. This strategy of reversibly transforming the structural layout has been employed for designing materials with switchable properties and functionalities, for example, tunable Poisson’s ratio, phononic and photonic switches, and color displays. In all these designs, notably, the behavior of the material in the post-transformation regime is dictated by instability-induced patterns. However, in a purely mechanical setting, the range of admissible patterns is highly restricted. In our work, we address this issue by designing soft multiphase composites with magnetoactive constituents. We show that the utilization of the magneto-mechanical coupling provides new ways to expand the design space for soft tunable materials.