An efficient closed-loop design framework for additive manufacturing of multiphysical metamaterials

Achieving multifunctionality has long been a key objective in the development of functional materials. Metamaterials have emerged as a promising solution due to their exceptional ability to manipulate physical fields. However, current metamaterial design methods predominantly rely on priori approaches. While these methods suffice for designing metamaterials targeting a single physical field, they are inadequate for multiphysical metamaterials characterized by high-dimensional design variables and complex hyperparameters. To address these challenges, this study proposes an efficient closed-loop design framework tailored for multiphysical metamaterials. Through this framework, a freeform metadevice was successfully designed to combine mechanical load-bearing, thermal protection, and low-loss electromagnetic wave transmission. This method integrates data-driven optimization design of multiphysical performance with lightweight requirements, and manufacturability of metamaterials. Compared with an unoptimized standard periodic reference structure, both simulation and experimental results show that the multiphysical metadevice achieves a 113.3% enhancement in load-bearing performance and a 13.4% reduction in relative density, while satisfying the requirement for thermal protection and low-loss electromagnetic wave transmission. This method can be extended to the design of other types of multiphysical metamaterials, establishing a new paradigm for the engineering application of functional materials, the design of multiphysical functional structures, and the integrated design and manufacturing process.