Magnetic Actuation Under DC and AC Fields of Thermoplastic Polyurethane With Strontium Hexaferrite

Abstract The growing field of applications where magnetic actuation is required relies on significant developments in materials science, particularly using polymer matrices to enhance the design and multifunctionality of small‐sized devices through additive manufacturing techniques. Thermoplastic polyurethane (TPU) is widely used for fused deposition modeling 3D printing technology and, as an elastomer, confers the degrees of freedom necessary to develop soft actuators capable of complex shape deformations. Such actuators can be triggered through different stimuli, with magnetic actuation standing out for its capacity to induce fast deformations of remotely actuated systems. Magnetic TPU composites with strontium hexaferrite (SrFe 12 O 19 ) were produced through a solvent‐free melt‐mixing technique. These composites display a magnetomechanical actuation mechanism, being able to deform (bend and twist) through DC and AC magnetic fields, showcasing their potential as a promising material for the fabrication of future magnetic actuators.