高磁导率材料FeCuNbSiB对超磁致伸缩/压电层合材料磁电性能的影响

摘要

A brand-new magnetostrictive/piezoelectric laminated composite is presented using the giant magnetostrictive Terfenol-D, piezoelectric PZT and high-permeability FeCuNbSiB. Since the high-permeability FeCuNbSiB changes the effective magnetic field in the Terfenol-D and the deformed FeCuNbSiB applies a stress to the Terfenol-D in an external magnetic field, thus the saturation magnetostrictive coefficient of Terfenol-D is enhanced, resulting in a higher magnetoelectric voltage output for the composite. Based on the equivalent magnetic charge theory, the effect of the FeCuNbSiB on the effective magnetic field in the Terfenol-D is analyzed, and the magnetostrictive coefficient of Terfenol-D and the theoretical formula of low-frequency magnetoelectric voltage coefficient are derived based on the nonlinear constitutive model of magnetostrictive material and the equivalent circuit method. The analytical results accord with the experiments qualitatively, and the magnetoelectric voltage of the composite is 1. 3 times as high as that of the Terfenol-D/ PZT-8H (MP) composite. The experimental results indicate that the thickness of FeCuNbSiB has a great influence on magnetoelectric property. The magnetoelectric voltage coefficient increases nearly linearly with the increase of the thickness of FeCuNbSiB until 180μm.%采用超磁致伸缩材料TbxDy1-xFe2(x≈0.3)(Teffenol-D)、压电材料PbZrxTi1-xO3(PZT)和高磁导率材料FeCuNbSiB构造了新型的层合结构.由于引入高磁导率材料FeCuNbSiB改变了Terfenol-D的内部磁场分布,并且在磁场作用下,FeCuNbSiB发生形变对Terfenol-D产生应力,增大了Terfenol-D的饱和磁致伸缩系数,使得该层合结构具有更高的磁电电压输出.利用磁荷理论,分析了FeCuNbSiB对Terfenol-D内部有效磁场分布的影响,并采用磁致伸缩材料Terfenol-D的非线性本构关系和等效电路法研究了FeCuNbSiB对其磁致伸缩系数的影响以及该层合结构的低频磁电电压系数理论计算公式.通过实验研究表明:理论值和实验值定性符合,且该结构的低频最大磁电电压系数是Terfenol-D/PZT-8H(MP)层合结构的1.3倍.同时发现,当FeCuNbSiB厚度小于180 μm时,层合结构的最大磁电电压系数与高磁导率材料FeCuNbSiB的厚度呈线性关系.