Some new aspects of boundary conditions at cracks in piezoelectrics
Some new aspects of boundary conditions at cracks in piezoelectrics
复制标题
压电体裂纹边界条件的一些新方面
DOI：
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
A. Ricoeur
中科院分区：
文献类型：
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作者：
R. Gellmann;A. Ricoeur
压电材料作为智能结构的组成部分的断裂力学研究在过去的30年中已经成为热门。在早期的研究中，裂纹面的边界条件是在假设边界是无牵引力的情况下从纯力学系统中获得的。从静电的观点来看，裂纹被假定为不带电荷或完全可渗透。后来，有限渗透裂缝边界条件在社区中流行起来，但仍然假设无牵引裂缝面。最近，理论框架已扩展到包括静电引起的裂纹模型产生显着的裂纹闭合效应的机械牵引。然而，这些模型仍然很简单，忽略了，例如，压电场耦合。在这项工作中，我们提出了一个扩展模型的裂纹表面牵引力产生一些有趣的效果。特别地，电场相对于极化轴的取向变得重要。此外，施加平行于裂纹面的共线应力影响模式I应力强度因子和模式II剪切加载耦合到模式I SIF。
Fracture mechanical investigations of piezoelectric materials as components of smart structures have become popular in the last 30 years. In the early years of research, boundary conditions at crack faces have been adopted from pure mechanical systems under the assumption that boundaries were traction free. From the electrostatic point of view, cracks have been assumed to be either free of charge or fully permeable. Later, limitedly permeable crack boundary conditions have become popular among the community, nevertheless still assuming traction-free crack faces. Recently, the theoretical framework has been extended to include electrostatically induced mechanical tractions in crack models yielding a significant crack closure effect. However, these models are still simple, neglecting, e.g., the piezoelectric field coupling. In this work, we present an extended model for crack surface tractions yielding some interesting effects. In particular, the orientation of the electrical field with respect to the poling axis becomes important. Furthermore, applying a collinear stress parallel to the crack faces influences the Mode-I stress intensity factor and a Mode-II shear loading couples to the Mode-I SIF.