超磁致伸缩材料Terfenol—D在机械应力作用下,磁化强度会发生变化,这种效应为逆磁致伸缩效应或Villari效应,利用该效应可以制作将机械能转换成电能的振动传感器。进行振动传感器的实验研究,结果表明在合适的偏置磁场和较小的预应力偏置条件下,传感器输出的感应电压峰一峰值较大,传感器输出感应电压的峰一峰值和输入振动信号的频率和幅值成正比。基于电磁学原理和铁磁材料的磁化强度模型,计算振动传感器的偏置磁场和预应力对感应电压输出的影响,并计算振动传感器在机械振动输入条件下的感应电压输出,实验结果与计算结果基本相符。实验结果和计算结果为振动传感器的优化设计和应用打下基础。
When applying mechanical stress to giant magnetostrictive material Terfenol-D, the magnetization along the direction of the applied stress varies due to the reverse magnetostrictive effect, which is called Villari effect. A magnetostrictive vibration sensor, which converts mechanical energy to electric energy, can be designed based on this effect. The experiment of the sensor was provided and the results show that peak to peak value of the sensing voltage is higher when the bias magnetic field is appropriate and the prestress is less. The voltage is proportional to frequency and amplitude of the mechanical stress. Based on the electromagnetic principle and the magnetization model of ferromagnetic material, the effect of the bias magnetic field and the prestress on the sensing voltage of the sensor can be calculated, and the voltage under different mechanical vibration input can also be calculated. It is found that the calculating results are in a good agreement with the experimental ones. The experimental and calculation results can provide the groundwork of optimizing design and application of the magnetostrictive vibration sensor.