Hysteretic Buckling for Actuation of Magnet-Polymer Composites

The development of bioinspired, novel, high-performance, "artificial muscle" materials is a topic of high current interest. Flexibility for folding and actuation are key parameters in the development of such artificial muscles, especially for self-assembly and origami engineering. A current challenge is to develop a multifunctional material that combines the biological functions of actuation, sensing, and healing. In this work, for the first time experimental and modeling results of the actuation capability of a multifunctional magnet-polymer (Magpol) composite material that is already capable of damage sensing and self-healing are reported. Actuation by constrained buckling of Magpol in an external magnetic field shows two buckling modes. The stress and strain are studied and optimized for various actuator geometries. Work density of up to 16 J kg^-1 is obtained, comparable to electroactive polymers. Magpol is successfully able to lift more than four times its own weight at relatively low applied magnetic field. Good agreement is observed between the experimental and modeling results. An Ashby design chart is employed to compare its performance to other actuators. This work provides insight into the development of next generation flexible, active multifunctional materials. The development of flexible "artificial muscle" actuators is a topic of interest especially for self-assembly and origami engineering applications. This work studies the actuation of magnet-polymer composites in a novel buckling mode. The stress and strain are optimized to obtain a work density comparable to electroactive polymers. This work provides insight into the development of next generation active materials.