Li Weichen, Wang Yue, Chen Tian, Zhang Xiaojia Shelly
Department of Civil and Environmental Engineering, University of Illinois Urbana-Champaign, Urbana, IL 61801, USA.
Department of Mechanical Engineering, University of Houston, Houston, TX 77204, USA.
Sci Adv. 2023 Nov 24;9(47):eadk0620. doi: 10.1126/sciadv.adk0620. Epub 2023 Nov 22.
We envision programmable matters that can alter their physical properties in desirable manners based on user input or autonomous sensing. This vision motivates the pursuit of mechanical metamaterials that interact with the environment in a programmable fashion. However, this has not been systematically achieved for soft metamaterials because of the highly nonlinear deformation and underdevelopment of rational design strategies. Here, we use computational morphogenesis and multimaterial polymer 3D printing to systematically create soft metamaterials with arbitrarily programmable temperature-switchable nonlinear mechanical responses under large deformations. This is made possible by harnessing the distinct glass transition temperatures of different polymers, which, when optimally synthesized, produce local and giant stiffness changes in a controllable manner. Featuring complex geometries, the generated structures and metamaterials exhibit fundamentally different yet programmable nonlinear force-displacement relations and deformation patterns as temperature varies. The rational design and fabrication establish an objective-oriented synthesis of metamaterials with freely tunable thermally adaptive behaviors. This imbues structures and materials with environment-aware intelligence.
我们设想了一种可编程物质,它可以根据用户输入或自主感知,以理想的方式改变其物理性质。这一设想推动了对能够以可编程方式与环境相互作用的机械超材料的探索。然而,由于高度非线性变形以及合理设计策略的不完善,软超材料尚未系统地实现这一目标。在此,我们利用计算形态发生和多材料聚合物3D打印技术,系统地创建了在大变形下具有任意可编程温度可切换非线性力学响应的软超材料。这是通过利用不同聚合物独特的玻璃化转变温度实现的,当这些聚合物被优化合成时,它们能够以可控的方式产生局部和巨大的刚度变化。所生成的结构和超材料具有复杂的几何形状,随着温度变化,呈现出截然不同但可编程的非线性力-位移关系和变形模式。这种合理的设计和制造建立了一种面向目标的超材料合成方法,其热适应性行为可自由调节。这赋予了结构和材料环境感知智能。