磁流变弹性体剪切式动态力学性能测试

Dynamic mechanical properties testing for shear mode of magnetorheological elastomer

磁流变弹性体(MRE)是磁流变材料中新的一员,研究磁流变弹性体材料,其动态力学性能的探究是研究的重要组成部分,建立一套磁流变弹性体动态力学性能测试系统是需亟待解决的问题。设计了一种磁流变弹性体剪切式动态力学性能测试装置,由电磁振动台提供稳定的正弦激励,通过可调间距的钕铁硼永磁体产生可变的磁场,利用安装在测试系统中的力与加速度传感器,获取磁流变弹性体在往复剪切运动中的剪切力与加速度信号,其中加速度信号经两次数值积分获得位移数据,通过力与位移数据建立磁流变弹性体在动态剪切模式下的应力-应变关系,结合粘弹性材料理论模型,得到磁流变弹性体在剪切模式下的磁控动态力学性能参数。为研制高性能的磁流变弹性体提供了评价体系。

Magnetorheological elastomer（MRE） is a new member of the magnetorheological materials and dynamic mechanical properties of MRE is an important part of studing MRE materials.The establishment of dynamic mechanical properties testing system is the problem which must to be solved.This work designed a device for testing dynamic mechanical properties of MRE,which steady sinusoidal signal was provided by electromagnetic vibration.Magnetic field strength can be changed by adjusting the spacing of NdFeB permanent magnet during the experiment.Force sensor and accelerometer installed on the testing system to get shear stress and acceleration signal of MRE in shear motion and displacement data can be calculated from two acceleration integration.Dynamic shear stress-strain relationship of MRE established through the force and displacement data,therefore,dynamic mechanical properties of MRE under shear mode were obtained by combining theoretical model of viscoelastic material.The system will provide a necessary guidance for preparation high performance MRE.