压电-磁致伸缩双层磁电复合材料的机电谐振

基于压电相和磁致伸缩相的本构方程以及弹性体的运动方程,简要推导了一维机电谐振模式下压电-磁致伸缩双层磁电复合材料横向磁电电压系数的表达式。采用相应的材料参数计算分析了Tb_1-x Dy_x Fe_2-y (TDF)-Pb(Zr,Ti)O₃(PZT)双层磁电复合材料的横向磁电电压系数与交流磁场频率的关系,以及复合材料的长度和压电相体积分数对机电谐振频率的影响。计算与分析结果表明,双层磁电复合材料在机电谐振频率处具有明显的磁电 响应特性。当有效机械品质因数为50,在谐振频率55.2 kHz处横向磁电电压系数达到峰值11.2 V·cm^-1·Oe^-1,是低频下峰值(281.9 mV·cm^-1·Oe^-1)的40倍。机电谐振频率随复合材料长度的减小和压电相体积分数的增加而上升。实验结果说明TDF-PZT双层磁电复合材料在机电谐振频率处具有显著增强的磁电效应,实际有效机械品质因数约为48。

Electromechanical resonance of piezoelectric magnetostrictive bilayer

The transverse magnetoelectric voltage coefficient of piezoelectric-magnetostrictive bilayer at the electromechanical resonance (EMR) was derived according to the constitutive equations of piezoelectric and magnetostrictive phases, and the equation of motion. As a function of frequency, the transverse magnetoelectric voltage coefficients of Tb_1-x Dy_x Fe_2-y (TDF)-Pb(Zr,Ti) O₃ (PZT) bilayer had been calculated using the corresponding material parameters of individual phases. The resonance frequency was calculated using different length and volume fraction of piezoelectric phase, and the dependence of frequency on the two parameters was analyzed. The results indicate that the bilayer shows strong resonance character at resonance frequency. The transverse magnetoelectric voltage coefficient can reach peak value 11.2 V·cm^-1·Oe^-1 at 55.2 kHz when effective mechanical quality factor is 50, which is about 40 times as high as that at the low frequency (281.9 mV·cm^-1·Oe^-1). The resonance frequency rises with shortening the length and increasing the volume fraction of piezoelectric phase. TDF-PZT bilayer is fabricated and the relevant experiment is carried out to verify the calculated results. The actual effective mechanical quality factor is about 48.