磁流变弹性体的可编程磁致形变及其优化机理研究

Magnetorheological elastomer (MRE) has excellent magnetic-control mechanical properties and as deformation driven material, it has great application prospect in the soft actuators. By combining the advantages of multi-scale material design method and additive manufacturing technology, this project innovatively plans to design and develop composite MRE with programmable magneto-deformation. This project proposes a multi-scale material design method for the novel MRE. Thereinto, the magnetic field is used to control the aggregation state and magnetic domain of the magnetic particles, and the 3D printing technology is used to realize the distribution design and topology optimization of the magnetic moment. It is proposed to characterize the magneto-deformation and microstructure by using advanced three-dimensional observation technology, and to clarify the influences of driving magnetic field, matrix, particle aggregation state and particle magnetic characteristics on magneto-deformation. It is proposed to construct the transition relationship between microscopic particles and macroscopic deformation based on the finite element analysis method. Combining the theory of micro-magnetism with the theory of non-uniform dielectric elasticity, the force-magnetic coupling mechanism of the magneto-deformation is analyzed by means of multi-physics coupling simulation. Finally, this project will establish a macro-microscopic theoretical model for the magneto-deformation of MRE. The successful implementation of this project will not only deepen the understanding of the magnetic-control properties but also open up new ways for the material design and preparation methods of MREs. It will provide new design theories and technical supports for the significant needs of soft actuators in the fields of bionics, actuation, and sensing.

磁流变弹性体（MRE）具有优异的磁控力学特性，作为形变驱动材料在柔性致动器领域具有巨大的应用前景。本项目拟结合多尺度材料设计方法与增材制造技术的优势，创新性地设计和研制具有可编程磁致形变特性的复合MRE材料。拟提出MRE的多尺度材料设计方法，借助磁场调控磁性颗粒的聚集态与磁畴，采用3D打印技术实现对磁矩的分布设计及拓扑优化。利用先进三维观测技术对磁致形变和微观结构进行表征，厘清磁场、基体、颗粒聚集态、颗粒磁学特性等因素对磁致形变的影响。基于有限元分析方法构建细观颗粒与宏观形变的过渡关系，将微磁学理论与非均匀介质弹性理论相结合，借助多物理场仿真分析MRE磁致形变的力-磁耦合机制，最终建立MRE磁致形变的宏-细观理论模型。本项目的成功实施不仅能加深对于MRE磁致特性的理解，为MRE的材料设计与制备方法开辟新的途径，还将为柔性致动器在仿生、致动、传感等领域的重大需求提供新的设计理论和技术支撑。

磁流变弹性体是将微米级磁性颗粒分散于高分子弹性体中复合而成的一种智能材料，具有优异的磁控力学性能和形变驱动功能。针对磁流变弹性体在柔性驱动和智能结构领域的应用，本课题聚焦于磁致形变的可编程设计和优化机制研究，并初步开展了其在柔性驱动器件以及智能吸波结构上的应用研究。课题在形变设计理论、多物理场模型、结构拓扑优化方法、3D打印制造系统、柔性驱动器件、可调谐电磁吸波结构、力-电-磁耦合测试系统等方面取得了一定成果。首先搭建了磁流变材料的3D打印制造系统，开发了形状记忆磁敏线材，实现了多种磁敏结构的3D打印制造。其次基于弹性理论和磁学理论提出了一种基于软磁材料的形变可编程策略。通过3D打印具有不同取向性的磁性微结构，从而对磁流变弹性体的磁力矩进行调控，实现了磁致形变的可编程设计。另外借助热-磁耦合场诱导磁性颗粒的聚集态重构，确保了磁致形变可编程设计的可重复和多样性。通过多物理场仿真建立了磁致形变的物理模型，搭建了力-磁-电测试系统，系统地研究了磁致形变的输出力、可重复性、响应时间等性能。开发了多种具有优异驱动性能的磁控柔性驱动器件和仿生软体机器人，包含仿尺蠖、仿蝠鲼、仿章鱼等软体机器人，以及用于抓取的柔性夹持器。另外针对柔性驱动器件的驱动传感一体化需求，本课题提出结合电子皮肤的感知功能，实现了对柔性驱动器件的接触和弯曲感知，获得了稳定灵敏的信号输出，为磁控柔性驱动器件的驱动传感一体化提供了技术途径。课题最后拓展了磁敏结构在电磁吸波领域的应用研究，提出通过磁场诱导微观结构实现可调谐电磁吸波体的制造。结合热-磁场的耦合效应和拓扑优化理论，开发了“吸收强，性能稳”的可调谐磁敏吸波结构。本课题提出的关于磁流变材料和器件的设计理论、制造方法和多场耦合模型等研究成果不仅为磁敏柔性驱动器件的应用提供方法和途径，还将为拓展其在电磁吸波、减振降噪等领域的应用研究提供理论和实验基础。