Hoberman-sphere-inspired lattice metamaterials with tunable negative thermal expansion
Hoberman-sphere-inspired lattice metamaterials with tunable negative thermal expansion
复制标题
DOI：
10.1016/j.compstruct.2018.01.108
复制
发表时间：
2018-04-01
影响因子：
6.3
通讯作者：
Wang, Lifeng
中科院分区：
文献类型：
--
作者：
Li, Yangbo;Chen, Yanyu;Wang, Lifeng
具有工程热膨胀系数的材料能够避免结构和器件的失效或不可逆破坏，在航空航天、民用、生物医学、光学和半导体应用中具有重要意义。在天然材料中，热膨胀通常不容易调整，负的热膨胀系数仍然很少见。在这里，我们提出了一种新颖的格子双材料体系，灵感来自Hoberman球，表现出从负到正的宽范围可调热膨胀系数，从-1.04×10(-3)℃-1到1.0×10(-5)℃-1。数值模拟和解析公式被用来量化热膨胀系数的演化，并揭示了导致这种异常行为的潜在机制。结果表明，超材料的热膨胀系数取决于组成材料的热膨胀系数比和轴向刚度比，以及本构单元的弯曲刚度和拓扑排列。这一发现为设计具有可调负热膨胀的超材料体系提供了新的途径，具有广泛的潜在应用前景。
Materials with engineered thermal expansion coefficients, capable of avoiding failure or irreversible destruction of structures and devices, are important for aerospace, civil, biomedical, optics, and semiconductor applications. In natural materials, thermal expansion usually cannot be adjusted easily and a negative thermal expansion coefficient is still uncommon. Here we propose a novel architected lattice bi-material system, inspired by the Hoberman sphere, showing a wide range of tunable thermal expansion coefficient from negative to positive, -1.04 x 10(-3) degrees C-1 to 1.0 x 10(-5) degrees C-1. Numerical simulations and analytical formulations are implemented to quantify the evolution of the thermal expansion coefficients and reveal the underlying mechanisms responsible for this unusual behavior. We show that the thermal expansion coefficient of the proposed metamaterials depends on the thermal expansion coefficient ratio and the axial stiffness ratio of the constituent materials, as well as the bending stiffness and the topological arrangement of the constitutive elements. The finding reported here provides a new routine to design architected metamaterial systems with tunable negative thermal expansion for a wide range of potential applications.