Magnetorheological (MR) materials, a class of smart materials that can reversibly change rheological and mechanical properties under magnetic fields15,16,17, are composed of soft magnetic particles within a fluid or elastomeric carrier18,19. Under external magnetic fields, the magnetized particles attract each other through dipole-dipole interaction to form fibre-like structures-known as the MR effect-that increase the viscosity and stiffness of the MR materials20,21. Among these materials, anisotropic MR elastomers with predefined fibre-like soft magnetic structures exhibit directional responses, including sheer stiffening22 and rotational actuation23, to magnetic fields.
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