含磁电弹夹层的压电/压磁声子晶体带隙特性研究

将具有力电磁耦合性能的夹层引入到压电/压磁声子晶体中,在保持单胞长度为固定值的情况下,分别改变磁电弹夹层的厚度、磁电弹夹层中压电材料的体积分数和磁电弹夹层中压电材料的种类;并利用传递矩阵法和Bloch定理,得到波数k与频率ω的色散关系;通过色散关系图分析不同的磁电弹夹层对压电/压磁声子晶体带隙特性的影响.研究发现:当磁电弹夹层厚度增加时,带隙的中心频率上升,带隙宽度变宽;当磁电弹夹层中压电材料体积分数增加时,带隙中心频率下降,第一带隙宽度变窄,第二带隙宽度增加,第三带隙宽度保持不变;当磁电弹夹层中的压电材料种类不同时,带隙的中心频率和带隙宽度有明显的改变;磁电弹夹层对压电/压磁声子晶体带隙中心频率的影响在高频区比低频区更显著.

Band gaps of piezoelectric/piezomagnetic phononic crystal with magneto-electro-elastic interlayer

Laminate piezoelectric (PE)/piezomagnetic (PM) composites consisting of alternating PE and PM layers can facilitate the conversion of energy between electric and magnetic fields, i.e., they possess the magneto-electric (ME) coupling effects, which recently has attracted much attention due to the huge potential applications in the field of high technology. The PE/PM phononic crystal is an ideal material for manufacturing high-tech precision parts such as resonator components, magnetoelectric sensors, weak magnetic field detectors, electric field tunable filters and magnetic field probes. In the practical applications, the adhesive interfaces of PE/PM phononic crystals are prone to deformation and failure during their use, because of the big difference between PE and PM material. In this paper, the magneto-electro-elastic (MEE) interlayer of magneto-electro-mechanical coupling is introduced into the PE/PM phononic crystal. The thickness of the MEE interlayer, the volume fraction of the piezoelectric material in the MEE interlayer and the type of the piezoelectric materials in the MEE interlayer are changed separately, with the thickness of the unit cell kept at a fixed value. The dispersion relation between the k and the ω is obtained by using the transfer matrix method and Bloch theorem. The influence of MEE interlayer on the band gap characteristics of PE/PM phononic crystal is studied by the dispersion relation diagram. The results show that as the thickness of the MEE interlayer increases, the central frequency of the band gaps shifts toward a higher frequency and the width of band gap becomes wider. As the volume fraction of the piezoelectric material increases, the center frequency and the width of the first band gap decrease. However, the width of the second band gap increases, and the width of the third band gap remains unchanged. The type of piezoelectric material in the MEE interlayer has an obvious influence on both the width and the central frequency of the band gaps. The effect of MEE interlayer on the central frequency of band gap of PE/PM phononic crystal is more significant in the high frequency region than in the low frequency region. Therefore, the width and central frequency of the band gaps can be adjusted to a certain extent by adding different MEE interlayers into the phononic crystal structure when designed.