基于自适应差分进化算法的多晶pzt压电陶瓷非线性模型优化研究系统工程专业论文.docxVIP

优秀毕业论文 精品参考文献资料 AbstractPZT Abstract PZT piezoelectric ceramics ale one of the most typical piezoelectric ceramic materials．And due to their high efficiency of electromechanical energy conversion properties，PZT piezoelectric ceramics are widely used in smart structure for sensor and actuator applications．With the increase of the strength of the outer field，traditional piezoelectric constitutive relation falls to characterize the nonlinear ferroelectric response of PZT piezoelectric ceramics．At present the research of nonlinear ferroelectric response and cognition are limited，which seriously restrict the further promotion and application of PZT piezoelectric ceramics．The main reason that result in the nonlinear ferroelectric response of PZT piezoelectric ceramics is the occurrence of domain switching in their microstructure．Therefore，an accurate description of the constitutive laws for domain switching is of benefit to the study of nonlinear ferroelectric response of piezoceramic materials． In order to study the nonlinear ferroelectric response of PZT piezoelectric ceramics， this article describes the quantitative relationship between the volume fractions of domain variants of a single grain and the free energy of grains．The exploration of domain switching process and nonlinear ferroelectric response of PZT piezoelectric ceramics are researched from the viewpoint of optimization．A mathematical optimization model based on the volume fractions of domain variants is established to reach the optimization goal of minimize the free energy of a single grain．To get the volume fractions of each domain variants of each grain under electrical loading，self- adaptive differential evolution algorithm that has extraordinary search performance is used to optimize the model．The interaction between grains of polycrystalline PZT piezoelectric ceramic materials is calculated by applying finite element method，and the macroscopic nonlinear response of the polycrystalline PZT piezoelectri