Terfenol-D/SAW谐振器/Terfenol-D复合磁传感器

设计了一种由超磁致伸缩材料Terfenol-D和SAW谐振器构成的复合磁传感器,在磁场作用下,Terfenol-D沿长度方向伸缩,并将应力应变传递至SAW谐振器,使其产生应变,造成谐振频率改变,通过测量SAW谐振器谐振频率的变化来测量磁场强度.分析了该磁传感器的传感原理,建立了该复合磁传感器的静态模型,对弹性敏感元件进行了受力分析,根据压磁方程和受力平衡得到该磁传感器的静态特性.实验结果表明:该复合磁传感器灵敏度可达341.6Hz/Oe,较Terfenol-D/SAW谐振器结构灵敏度提高了3倍;测量谐振频率的分辨率为1Hz,SAW谐振器频率稳定度为0.1×10-6时,该磁传感器对磁场的分辨率为10-6T.

Terfenol-D/SAW resonator/Terfenol-D composite magnetic sensor

A composite magnetic sensor consisting of giant magnetostrictive material Terfenol-D and a SAW resonator is designed. The resonant frequency of the SAW resonator varies with the stress induced magnetically. Resultantly, the magnetic field strength can be measured by the variation of the resonant frequency. The principle of the magnetic sensor is analyzed. The static model of the composite magnetic sensor is established and the stress of elastic sensing element is analyzed. Based on the piezo-magnetic equations and equilibrium of force, the static characterization of the composite magnetic sensor is obtained. Experimental results indicate that the static sensitivity of the composite magnetic sensor can reach 341.6Hz/Oe, and the resolution of the magnetic field can reach 10-6 Tesla when the resolution of frequency detection is 1Hz and the frequency stability of SAW resonator is 0.1ppm.