Nucleation and growth of domains near crack tips in single crystal ferroelectrics
Nucleation and growth of domains near crack tips in single crystal ferroelectrics
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DOI：
10.1016/j.engfracmech.2011.01.002
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发表时间：
2011-05
影响因子：
5.4
通讯作者：
Wenyuan Li;C. Landis
中科院分区：
文献类型：
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作者：
Wenyuan Li;C. Landis
研究了铁电材料单晶中静止裂纹尖端附近畴的形核与生长。相场法，应用材料的极化作为序参量，被用来作为理论建模框架和有限元方法用于数值求解技术。的J-积分的机电形式进行了适当的修改，以占极化梯度能量项，并进行分析，以说明屏蔽量，或缺乏，由于域切换在裂纹尖端。结果表明，外加电场引起的裂纹尖端畴形核受外加应力的影响。然而，在畴形核时刻和最终平衡畴结构之间，裂纹尖端能量释放率会发生显着变化。这些结果的铁电单晶断裂准则的影响进行了讨论。
The nucleation and growth of domains is investigated near a stationary crack tip in a single crystal of ferroelectric material. The phase-field approach, applying the material polarization as the order parameter, is used as the theoretical modeling framework and the finite element method is used for the numerical solution technique. The electromechanical form of the J-integral is appropriately modified to account for the polarization gradient energy terms, and analyzed to illustrate the amount of shielding, or lack thereof, due to domain switching at the crack tip. It is shown that the nucleation of domains near the crack tip due to applied electric field is affected by applied stress. However, the crack-tip energy release rate can change significantly between the instant of domain nucleation and the final equilibrium domain configuration. Implications of these results for ferroelectric single crystal fracture criteria are discussed.