Shaping Magnetic Liquid Metals Into 3D Leakage-Free, Shape-Programmable Structures and Electronics

This study introduces a novel approach for fabricating 3D leakage-free, reconfigurable magnetic liquid metal (MLM) structures through magnetically immobilized gallium composites. By dispersing NdFeB microparticles into liquid gallium and magnetizing the mixture, a porous magnetic network was formed that immobilized the liquid metal while maintaining high electrical conductivity. The composite was mechanically programmed within elastomer molds to create freestanding 3D shapes that exhibit reversible transitions between 2D and 3D configurations via induction heating and magnetic-assisted reprogramming. Mechanical testing demonstrated high compressive resilience and self-healing capability, while functional prototypes such as wireless antennas and optogenetic implants validated performance in communication and energy harvesting applications.