Metamaterials refer to man-made materials with properties that natural materials do not possess, and are usually composed of periodically arranged units. By adjusting the structural shape, geometric size and orientation of the internal unit of the material, metamaterials can realize the control of various physical properties such as light, sound, electromagnetic, and mechanical response, and obtain properties such as negative dielectric constant and negative Poisson's ratio. There is huge potential in many application fields such as equipment, aerospace and new energy. However, in the current related research, most metamaterial structures have fixed geometric shapes, or only realize passive deformation under mechanical loading. Therefore, the geometric shapes realized by a single material system are relatively limited, which limits the reconfigurability of materials in physical properties. .
Recently, the team of Professor Zhao Ruike of Ohio State University and the team of Professor Qi Hang of Georgia Institute of Technology used a coupled magneto-mechanical actuation to control the applied magnetic field direction, magnetic field amplitude and mechanical load, demonstrating the active performance Controlled magnetic metamaterial structure. The metamaterial is driven by a magnetic-mechanical coupling to realize a variety of structural and shape deformation modes, and has physical properties such as ultra-wide adjustable mechanical stiffness, Poisson's ratio, and elastic wave band gap. By using the temperature dependence of the modulus of the recently developed magnetic shape memory polymer (Magnetic shape memory polymer), the research further realizes the selective local tunability and global tunability of physical properties. The research results were recently published online in "Advanced Functional Materials" under the title "Magneto-Mechanical Metamaterials with Widely Tunable Mechanical Properties and Acoustic Bandgaps".