梯度材料的物理特性在空间上是连续变化的，由于其具备优良的功能特性，从而广泛运用到智能结构中。本项目研究板波在一维及二维周期性宏观和微观梯度压电和磁电弹性板中的不对称传播:首先研究板波在一维周期性宏观梯度压电和磁电弹性板中的不对称传播；接着研究板波在二维周期性宏观梯度压电和磁电弹性板中的不对称传播；再重点研究板波在一维和二维周期性微观梯度变化压电和磁电弹性板中的不对称传播，并详细分析板波在一维和二维周期性宏观和微观梯度变化的磁电板中的非互易单向传播；最后实验验证板波在周期性宏观和微观梯度弹性、压电材料板中的不对称传播以及周期性宏观和微观梯度变化磁电材料板中的非互易单向传播。本项目旨在揭示周期性宏观和微观材料板中板波的不对称传播和周期性宏观和微观梯度磁电材料板中的非互易单向传播。为功能梯度材料与结构的超声表征与检测提供必要的理论依据；并为板波的不对称传播和非互易单向传播提供理论和实验基础。

Graded materials are widely uesed in smart structures because its have excellent features and its' physical properties in space are continuous change.This project is intented to investigate asymmetric plate-mode waves propagation in one-dimensional(1D) and two-dimensional(2D) gradient-index and functionally graded piezoelectric and magneto-electro-elastic phononic crystal slabs: First asymmetric plate-mode waves propagation in 1D gradient-index piezoelectric and magneto-electro-elastic phononic crystal slabs and 2D gradient-index piezoelectric and magneto-electro-elastic phononic crystal slabs are studied; then it focuses on studing asymmetric plate-mode waves propagation in 1D and 2D functionally graded piezoelectric and magneto-electro-elastic phononic crystals slabs and plate-mode waves diode in 1D and 2D functionally graded magnetoelectric phononic crystal slabs;at last asymmetric plate-mode waves propagation in 1D and 2D graded phononic crystal salbs and plate-mode waves diode in 1D and 2D graded magneto-electro phononic crystal slabs are proved by experiment. This project aims to reveal the asymmetric plate-mode waves propagation in 1D and 2D graded piezoelectric and magneto-electro-elastic phononic crystal slabs and plate-mode waves diode in 1D and 2D gradient-index magnetoelectric phononic crystal slabs. It provides the theoretical basis for the research on development of the ultrasonic characterization and testing of functionally graded materials；It also provides the theoretical and experimental basis for asymmetric plate-mode waves and plate-mode waves diode.