铁电材料力-电非线性电滞与蝴蝶曲线综合模型研究

Comprehensive Modeling for Electro-Mechanical Nonlinear Hysteretic and Butterfly Curves in Ferroelectrics

铁电材料固有的电畴结构和极化反转特性引发宏观非线性行为,即极化电滞曲线和应力蝴蝶曲线,且由于材料、制备技术、电路系统等限制因素使得行为曲线出现不对称、中心偏移等现象,使得目前常规模型很难精确、有效地描述铁电系统的真实特性。针对此问题,提出一种适用于铁电材料的综合含参数模型用以有效模拟力、电及耦合非线性行为。该模型基于现有铁电模型理论并引入异化参数而形成,可广泛适用各类铁电曲线中存在的不对称和偏移等异化现象;此外,为了有效预测综合模型中多个未知特性参数,通过设计遗传算法程序实现其精确优化识别,为进一步提高模型预测精确性和实用性提供必要条件;最后,分别开展了虚拟试验和真实试验仿真模拟验证,结果表明:采用优化参数综合模型的模拟误差均可控制在10%以内,相较于传统模型方法可提高约50%。因此,该模型方法可广泛用于实际铁电材料特性行为的描述,且具有较好的应用前景。

Ferroelectric materials have domain structure and present switching behavior of the polarization, resulting in nonlinear characteristics of electric field-induced hysteretic polarization and butterfly-shaped strain. In addition, they also show abnormal performance of asymmetry and bias due to inevitable sophisticated factors in material processing, electric circuit, etc. In this sense, this paper presents a comprehensive parameterized model to simulate the electro- mechanical coupling properties in ferroelectrics. The model was formed from adding a set of extra parameters on the basis of ferroelectric model theory, and it can be used to describe the behaviors of all kinds of ferroelectrics. Genetic algorithm （GA） program was designed to optimize the values of the underdetermined parameters in the model. By this program, the model can be greatly improved in accuracy and practicality. Finally, the simulation verification was carried out by using synthetic and actual experimental data, and the simulation errors are below 10%, improved by about 50% compared with the traditional methods. The proposed approach can be extensively used to describe the behaviors of various ferroelectric materials, and has very goodapplication prospect.