Reprogrammable liquid-metal/NdFeB/silicone composite magnetic elastomer

Abstract

Programming the patterned magnetization profile on the magnetic elastomer can enable the magnetic soft robot to produce controlled deformation. But the magnetization profiles are usually unchangeable, which leads to the single function of magnetic soft robot. This paper presents a reprogrammable mangetic elastomer based on liquid-metal/NdFeB/Silicone composites. Liquid-metal/NdFeB functional groups wrapped in silicone matrix can realize repeated magnetization through thermal-assisted magnetic programming. By using several liquid metals (melting points <60 °C), we have manufactured composite magnetic elastomer with regulate-temperature at 15.7, 29.7, 41.5 and 47 °C, respectively. SEM and EDS results exhibits the elastomer’s micromorphology and element content. The elstomer’s magnetic properties are tested by the comprehensive physical property measurement system (PPMS). The moment–temperature (M–T) curve shows the material’s moment jumps at the melt point of the liquid metal. And the moment–magnetic field (M–H) curves indicate that the elastomer exhibit hard and soft magnetic characteristics. At last, a hexagon-shape robot is manufactured and then programmed to two modals of grasping and standing. The experimental results verify the reprogrammability of the proposed composite elastomer. The elastomer is expected to be utilized to manufacture multi-modal magnetic soft robot.