Li X W, Ji H M, Yang W, Zhang G P, Chen D L
Department of Materials Physics and Chemistry and Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), School of Material Science and Engineering, Northeastern University, Shenyang 110819, PR China.
Department of Materials Physics and Chemistry and Key Laboratory for Anisotropy and Texture of Materials (Ministry of Education), School of Material Science and Engineering, Northeastern University, Shenyang 110819, PR China; Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria Street, Toronto, Ontario, Canada M5B 2K3.
J Mech Behav Biomed Mater. 2017 Oct;74:54-71. doi: 10.1016/j.jmbbm.2017.05.022. Epub 2017 May 17.
The self-fabrication of materials in nature offers an alternate and powerful solution towards the grand challenge of designing advanced structural materials, where strength and toughness are always mutually exclusive. Crossed-lamellar structures are the most common microstructures in mollusks that are composed of aragonites and a small amount of organic materials. Such a distinctive composite structure has a fracture toughness being much higher than that of pure carbonate mineral. These structures exhibiting complex hierarchical microarchitectures that span several sub-level lamellae from microscale down to nanoscale, can be grouped into two types, i.e., platelet-like and fiber-like crossed-lamellar structures based on the shapes of basic building blocks. It has been demonstrated that these structures have a great potential to strengthen themselves during deformation. The observed underlying toughening mechanisms include microcracking, channel cracking, interlocking, uncracked-ligament bridging, aragonite fiber bridging, crack deflection and zig-zag, etc., which play vital roles in enhancing the fracture resistance of shells with the crossed-lamellar structures. The exploration and utilization of these important toughening mechanisms have attracted keen interests of materials scientists since they pave the way for the development of bio-inspired advanced composite materials for load-bearing structural applications. This article is aimed to review the characteristics of hierarchical structures and the mechanical properties of two kinds of crossed-lamellar structures, and further summarize the latest advances and biomimetic applications based on the unique crossed-lamellar structures.
自然界中材料的自我构建为设计先进结构材料这一重大挑战提供了另一种强大的解决方案，而在先进结构材料中，强度和韧性往往相互排斥。交叉层状结构是软体动物中最常见的微观结构，由文石和少量有机材料组成。这种独特的复合结构具有比纯碳酸盐矿物高得多的断裂韧性。这些结构呈现出复杂的分级微观结构，从微米尺度到纳米尺度跨越几个子层，可以根据基本构建块的形状分为两类，即片状和纤维状交叉层状结构。已经证明，这些结构在变形过程中具有很大的自我强化潜力。观察到的潜在增韧机制包括微裂纹、通道裂纹、互锁、未开裂韧带桥接、文石纤维桥接、裂纹偏转和曲折等，这些机制在增强具有交叉层状结构的贝壳的抗断裂能力方面起着至关重要的作用。这些重要增韧机制的探索和利用引起了材料科学家的浓厚兴趣，因为它们为开发用于承重结构应用的仿生先进复合材料铺平了道路。本文旨在综述分级结构的特点以及两种交叉层状结构的力学性能，并进一步总结基于独特交叉层状结构的最新进展和仿生应用。
