Toughening under non-uniform ferro-elastic domain switching
Toughening under non-uniform ferro-elastic domain switching
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DOI：
10.1016/j.ijsolstr.2005.05.015
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发表时间：
2006-07
影响因子：
3.6
通讯作者：
Yuanqing Cui;Wei Yang
中科院分区：
文献类型：
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作者：
Yuanqing Cui;Wei Yang
现有的切换增韧模型很少考虑裂纹附近非均匀铁弹性畴切换的影响。为了探讨这一问题，从最小能量原理出发，建立了受机电载荷作用下开关部分体积分数的演化规律。在此基础上，建立了能处理开关应变非均匀分布的开关模型。域切换区分为饱和的内核和活跃的环空。在小尺度域切换模型下，得到了铁弹性增韧的单域解。利用罗伊斯近似估计了不同极化态铁电体的增韧。根据球形和圆柱形夹杂得到了两组解。两种模型定义的增韧区间涵盖了实验数据的范围。对于切换区的大小也得出了同样的结论。
The existing models of switch-toughening seldom consider the effect of non-uniform ferro-elastic domain switching in the vicinity of a crack. To explore this issue, an evolution law for the volume fraction of the switched portion under applied electromechanical loading is established from the minimum energy principle. Based on this law, a switching model capable of dealing with the non-uniform distribution of switching strain is developed. The domain switching zone is divided into a saturated inner core and an active surrounding annulus. Mono-domain solution of ferro-elastic toughening is obtained under the model of small scale domain switching. Toughening for ferroelectrics with different poling states is estimated via Reuss type approximation. Two sets of solutions are obtained according to spherical and cylindrical inclusions. The interval of toughening defined by these two models covers the range of experimental data. The same conclusion is reached for the size of the switching zone.