声子晶体在声学抑制、超声成像、热控技术、国防工业、航空航天领域具有十分重要的应用前景，对其弹性波传播特征和带隙进行有效调控是这一领域的核心问题。磁敏感声子晶体作为一种新型智能声子晶体，不仅可以实现其带隙的磁场调控，而且蕴含丰富的非线性动力学行为，展开这一领域的研究十分必要。基于此本课题围绕非线性磁敏感声子晶体的弹性波传播特征及带隙调控展开研究，拟对其：1）建立完备的理论分析框架，寻求有效的非线性定量分析手段，揭示外加磁场、物理、几何和材料参数对其弹性波传播特征及带隙调控的影响规律；2）研究其弹性波单向传播的时空磁场调控模式及实现条件；3）展开相应的基础实验研究。通过这些研究：建立和完善磁敏感声子晶体弹性波传播的多场耦合非线性理论体系，编制有效的定量分析程序；揭示带隙磁场调控的特征和规律，进而为新型的、具有可调控和多功能特征的声学器件和声超材料、结构和装置的设计、分析和测试提供必要的支撑。

Phononic crystals have wide potential applications in engineering practice, such as in acoustic suppression, ultrasound imaging, thermal control technology, defense industry, aerospace. The effective tunability of the band gap and wave propagation characteristics is one of the key problems in this area. As a new kind intelligent material phononic crystal, the magneto-sensitive phononic crystal can not only realize the magnetic tunability of band gap, but also contain the fruitful nonlinear dynamic behaviors, it is very necessary to conduct the research on this field. Based on these, this project will conduct some research works focused on the wave propagation characteristics and band gap’s tunability, which are: 1) build a complete theoretical frame and find a new effective quantitative analytical approach, to reveal the influence rules of the applied magnetic field, physical, geometrical and materials’ parameters on the elastic wave propagation characteristic and band gap tunability of the nonlinear magneto-sensitive phononic crystals; 2) study the spatiotemporally modulation mode and the realized necessary conditions of the magneto-sensitive phononic crystals for nonreciprocal wave propagation; 3) conduct some basic experiments on the wave propagation and band gap tunability of magneto-sensitive phononic crystals. After that, a multi-field coupling, multi-nonlinear theoretical frame of the wave propagation in magneto-sensitive phononic crystals will be built, and the effective quantitative analysis approach and code will be developed and some rules about the band gap tunability will be revealed. All these will be provided a theoretical support for the design, analyses and test of the new, controllable and multi-functional phononic crystals and acoustic metamaterials, structures and devices.