Stress fluctuation, crack renucleation and toughening in layered materials
Stress fluctuation, crack renucleation and toughening in layered materials
复制标题
DOI：
10.1016/j.jmps.2018.04.011
复制
发表时间：
2018-11-01
影响因子：
5.3
通讯作者：
Bhattacharya, K.
中科院分区：
文献类型：
--
作者：
Hsueh, C-J;Avellar, L.;Bhattacharya, K.
已经证实，弹性性能的差异可以导致非均质材料的断裂韧性的提高。将层状材料作为一个模型系统，我们表明这种增强是两个明显现象的结果--第一，应力波动导致裂纹处的应力强度比宏观应用值小得多的区域；第二，当裂纹处于柔顺到刚性的界面从而需要重成核时，缺乏应力强度。利用理论、计算和实验的方法，我们研究了两种几何结构--层状材料和具有窄通道的层状材料--来分离这两种现象。在这两种介质中都存在应力波动，但只在层状介质中存在重成核。我们提供了增强韧性的定量估计。(C)2018爱思唯尔有限公司。保留所有权利。
It has been established that contrast in the elastic properties can lead to enhancement of fracture toughness in heterogeneous materials. Focussing on layered materials as a model system, we show that this enhancement is a result of two distinct phenomena - first, fluctuations in stress leading to regions where the stress intensity at the crack is considerably smaller than that of the macroscopically applied value; and second, the lack of stress intensity when a crack is at a compliant to stiff interface thereby requiring renucleation. Using theoretical, computational and experimental methods, we study two geometries - a layered material and a layered material with a narrow channel - to separate the two phenomena. The stress fluctuation is present in both, but renucleation is present only in the layered medium. We provide quantitative estimates for the enhanced toughness. (C) 2018 Elsevier Ltd. All rights reserved.