铁电陶瓷宏观单轴力电行为的双面模型

铁电陶瓷以其优越的力电耦合性作为新型的智能材料使用. 提出基于弹塑性双面理论的宏观铁电本构模型. 根据铁电陶瓷内部电畴在外电场和机械场作用下的微观运动，在宏观上除引入材料的畴变面外，还首次引入饱和面，并考虑以畴变面与饱和面之间的广义距离来表征铁电陶瓷的非线性行为. 数值计算结果与实验数据的比较表明所提出的初步理论可适当地反映力电加载下铁电陶瓷的宏观非线性行为.

Two-surface model of macroscopic electro-mechanical behavior for ferroelectrics under unaxial loading

Ferroelectric ceramics are widely used as new smart materials due to their strong coupling between electric and mechanical fields. Our aim is to present a macroscopic constitutive model for ferroelectric ceramics based on Two-Surface theory of Plasticity, According to the microscopic evolvements of domains in ferroelecrics under electric and mechanical loadings, a switching surface of material is introduced, and a saturated surface of material is proposed firstly. The general distance between the switching surface and the saturated surface is regarded as the internal variable, which expresses the non-linear behavior of ferroelectric ceramics. The predicted hysteresis and butterfly loops by this model are in good agreement with the form of loops observed experimentally.