Recent advances in additive manufacturing of complex geometries enabled the creation of mechanical metamaterials whose exotic properties are based on local control of complex cell geometries. Overhanging and free-hanging features that lack continuous support layers in the previous build volume cannot be directly manufactured, imposing a major design limitation. The resulting metamaterials are limited to single homogenous structural materials, and inherently self-supporting geometries, resulting in constraints of achievable architectures. Realizing arbitrary features is compelling but is inherently limited by process and material support constraints. Here we present a novel light-based additive manufacturing approach capable of printing arbitrary micro-architectures comprising a large array of internally suspended features, large span overhang, and high aspect ratio struts. This method eliminates the need for manual removal of internal supports and enables a suite of multi-functional metamaterials with a range of designed properties, including wide bandgaps for elastic waves at low frequency, switchable wave transmissions, and products requiring no post support removal. We describe the synthesis and rapid printing of a variety of metamaterials comprising an extensive array of suspended features and demonstrate their metamaterial behaviors. The proposed approach removes scale and unit cell limitations and is capable of achieving embedded features across multiple materials.

复杂几何形状的增材制造的最新进展使机械超材料的创造成为可能，其奇异特性基于对复杂细胞几何形状的局部控制。无法直接制造在先前构建体积中缺少连续支撑层的悬垂和自由悬垂特征，这造成了主要的设计限制。由此产生的超材料仅限于单一的同质结构材料，以及固有的自支撑几何形状，从而限制了可实现的架构。实现任意功能是引人注目的，但本质上受到工艺和材料支持的限制。在这里，我们提出了一种新型的基于光的增材制造方法，能够打印任意微架构，包括大量内部悬挂特征、大跨度悬垂、和高纵横比支柱。这种方法消除了手动移除内部支撑的需要，并实现了一套具有一系列设计特性的多功能超材料，包括低频弹性波的宽带隙、可切换的波传输以及不需要后支撑移除的产品。我们描述了包括大量悬浮特征的各种超材料的合成和快速打印，并展示了它们的超材料行为。所提出的方法消除了规模和单位单元的限制，并且能够实现跨多种材料的嵌入特征。包括用于低频弹性波的宽带隙、可切换波传输以及无需去除后支撑的产品。我们描述了包括大量悬浮特征的各种超材料的合成和快速打印，并展示了它们的超材料行为。所提出的方法消除了规模和单位单元的限制，并且能够实现跨多种材料的嵌入特征。包括用于低频弹性波的宽带隙、可切换波传输以及无需去除后支撑的产品。我们描述了包括大量悬浮特征的各种超材料的合成和快速打印，并展示了它们的超材料行为。所提出的方法消除了规模和单位单元的限制，并且能够实现跨多种材料的嵌入特征。