超磁致伸缩薄膜悬臂梁的非线性振动特性试验研究

超磁致伸缩薄膜(GMF)的振动特性是决定其驱动性能的重要因素。针对研制出的Cu基双层GMF(TbDyFe/Cu/SmFe),测量并分析了其磁致回线、矫顽力等磁化特性。在此基础上,采用基于激光位移传感器的薄膜振动特性试验装置,研究了Cu基GMF悬臂梁在低频低磁场下的振动特性,结果表明,Cu基GMF悬臂梁具有10阶超谐波共振特性,二、三阶超谐波共振的峰峰值均在35μm以上,且其一阶主共振呈现明显的"软弹簧"特征。最后,给出了直流偏置磁场和交流驱动磁场对Cu基GMF共振频率和振动幅值等驱动性能的影响规律,为设计开发低频低磁场驱动的GMF微执行器和微传感器提供试验参考。

Experimental Study of Non-linear Vibration Characteristics of Bimorph Giant Magnetostrictive Thin Film Cantilever

The vibration characteristics of giant magnetostrictive thin film（GMF）play an important role in determining the driving performances of micro-devices.In this paper,the magnetization hysteresis curve and the coercive force of the bimorph GMF with Cu substrate are measured by VSM.Thereafter,the vibration characteristics of Cu substrate GMF cantilever at low frequency magnetic field are detected and analyzed by the experimental device based on laser displacement sensor.The experimental results indicate that the Cu substrate GMF cantilever exhibits the characteristic of super harmonic resonance of order ten,and the peak-to-peak values of super harmonic resonance of both two and three are beyond 35 m.Moreover,the main resonance of order one shows markedly the property of ＂soft spring＂.Finally,the effect of the bias magnetic field and alternative magnetic field on resonance frequency and resonance amplitude are given,which can provide the experimental reference for developing and designing effective of micro-actuators and micro-sensors with bimorph GMF.