Numerical and Experimental Study of the Mechanical Response of Diatom Frustules
Numerical and Experimental Study of the Mechanical Response of Diatom Frustules
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DOI：
10.3390/nano10050959
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发表时间：
2020-05-01
期刊：
影响因子：
5.3
通讯作者：
Zschech, Ehrenfried
中科院分区：
文献类型：
--
作者：
Topal, Emre;Rajendran, Harishankaran;Zschech, Ehrenfried
硅藻晶体具有纳米到微米级的分层三维模式二氧化硅结构，可以成为轻量级结构材料设计的典范。然而，对于具有pennate对称性的晶体，其力学性能还没有系统的研究。提出了一种结合原位微压痕和基于高分辨率x射线计算机断层扫描（XCT）的有限元分析（FEA）方法，并将其应用于双颌双颌体结构。此外，还进行了扫描电镜和透射电镜研究，以获得有关可分辨结构和组成的详细信息。在原位micro-indentation研究Didymosphenia geminata细胞膜,主要是弹性变形行为与位移不连续/非线性观测。为了从得到的载荷-位移曲线中提取材料在弹性区域的特性，进行了弹性有限元模拟。杨氏模量为31.8 GPa。本文所描述的方法可以理解非常复杂结构的力学行为。
Diatom frustules, with their hierarchical three-dimensional patterned silica structures at nano to micrometer dimensions, can be a paragon for the design of lightweight structural materials. However, the mechanical properties of frustules, especially the species with pennate symmetry, have not been studied systematically. A novel approach combining in situ micro-indentation and high-resolution X-ray computed tomography (XCT)-based finite element analysis (FEA) at the identical sample is developed and applied to Didymosphenia geminata frustule. Furthermore, scanning electron microscopy and transmission electron microscopy investigations are conducted to obtain detailed information regarding the resolvable structures and the composition. During the in situ micro-indentation studies of Didymosphenia geminata frustule, a mainly elastic deformation behavior with displacement discontinuities/non-linearities is observed. To extract material properties from obtained load-displacement curves in the elastic region, elastic finite element method (FEM) simulations are conducted. Young's modulus is determined as 31.8 GPa. The method described in this paper allows understanding of the mechanical behavior of very complex structures.