Discontinuous crack-bridging model for fracture toughness analysis of nacre
Discontinuous crack-bridging model for fracture toughness analysis of nacre
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DOI：
10.1016/j.jmps.2012.04.011
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发表时间：
2012-08-01
影响因子：
5.3
通讯作者：
Gao, Huajian
中科院分区：
文献类型：
--
作者：
Shao, Yue;Zhao, Hong-Ping;Gao, Huajian
研究生物材料的结构-性能关系不仅可以深入了解其优异性能和功能的物理机制，而且有利于先进仿生材料的设计和制造。在本文中，我们提出了一种基于微观结构的断裂力学模型来研究片晶裂纹桥接机制的增韧效应。我们的理论分析证明了这种机制对珍珠质高韧性的关键贡献。研究发现，珍珠质的断裂韧性对片晶的尺寸表现出明显的依赖性，并给出了实现更高断裂韧性所需的片晶厚度和长度的优化范围。此外，还考察了有机相（或界面）的机械性能、珍珠层的有效弹性模量以及片晶的堆积模式等因素的影响。最后，根据我们的理论分析，提出了一些新型材料仿生设计的指南。 (C) 2012 Elsevier Ltd. 保留所有权利。
Studying the structure-property relation of biological materials can not only provide insight into the physical mechanisms underlying their superior properties and functions but also benefit the design and fabrication of advanced biomimetic materials. In this paper, we present a microstructure-based fracture mechanics model to investigate the toughening effect due to the crack-bridging mechanism of platelets. Our theoretical analysis demonstrates the crucial contribution of this mechanism to the high toughness of nacre. It is found that the fracture toughness of nacre exhibits distinct dependence on the sizes of platelets, and the optimized ranges for the thickness and length of platelets required to achieve higher fracture toughness are given. In addition, the effects of such factors as the mechanical properties of the organic phase (or interfaces), the effective elastic modulus of nacre, and the stacking pattern of platelets are also examined. Finally, some guidelines for the biomimetic design of novel materials are proposed based on our theoretical analysis. (C) 2012 Elsevier Ltd. All rights reserved.