The stiffness and strength of metamaterials based on the inverse opal architecture
The stiffness and strength of metamaterials based on the inverse opal architecture
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DOI：
10.1016/j.eml.2016.07.006
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发表时间：
2017-04-01
影响因子：
4.7
通讯作者：
Schneider, Gerold A.
中科院分区：
文献类型：
--
作者：
do Rosario, Jefferson J.;Berger, Jonathan B.;Schneider, Gerold A.
反蛋白石结构是一类最近显示出高比强度和高模数的机械超材料，本文通过仔细的耦合实验和有限元建模对其进行了进一步的研究。我们证明，这种结构可以用来获得优化的比强度和模数，同时提供可调的光学带隙和大面积制造。从二氧化硅反蛋白石结构开始，加入不同厚度的二氧化钛(10-34 nm)，在300-1000 kg m(-3)密度范围内，强度从41 Mpa逐渐增加到410 Mpa，弹性模数从1.7 Gpa增加到8.3 Gpa。模拟结果表明，这种反蛋白石结构在杨氏、剪切和体积弹性系数以及结构效率(总刚度)方面都优于最先进的八重态和各向同性桁架结构设计。模拟还预测了二氧化钛涂层和二氧化硅涂层中的应力在破坏时的理论拉伸屈服应力的数量级，表明控制缺陷数量的尺寸效应是导致高强度的原因。(C)2016爱思唯尔有限公司。保留所有权利。
The inverse opal architecture, a class of mechanical metamaterials recently shown to exhibit high specific strength and modulus, is further investigated here using carefully coupled experiments and finite element modeling. We demonstrate that this architecture can be exploited to achieve optimized specific strength and modulus, while simultaneously offering tunable optical bandgaps and large-area fabrication. Starting with a silica inverse opal structure and adding different thicknesses of titania (10-34 nm) the strength was gradually increased from 41 to 410 MPa and the elastic modulus from 1.7 to 8.3 GPa, within densities of 300-1000 kg m(-3). Simulations confirmed that the inverse opal structure can outperform the stateof- the-art octet-and isotropic-truss designs in terms of Young's, shear and bulk modulus, as well as in structural efficiency (total stiffness). Simulations also predict stresses in the titania coating and in the silica that are on the order of the theoretical tensile yield stresses at failure, indicating that size effects controlling defect population are responsible for the high strengths. (C) 2016 Elsevier Ltd. All rights reserved.