采用主要成分为高粘度线性聚硅氧烷的弹性胶泥为基体,制备了羰基铁粉质量分数为20％,40％和60％的磁流变胶泥.对磁流变胶泥的流变学特性和动态力学特性进行测试,描述了磁流变胶泥的本构关系并识别其参数,分析了磁场、铁粉含量、剪切应变以及剪切频率对粘弹性能的影响.结果表明,磁流变胶泥的本构关系能用 Herschel-Bulkley 模型进行描述；剪切应力、刚度的磁场可控范围宽(铁粉质量分数为60％的磁流变胶泥剪切应力调节范围16~128 kPa,储能模量可调范围0．52~3．28 MPa)；随铁粉含量和磁场的增加,剪切应力增大、弹性增加而粘性减小；不同磁场下磁流变胶泥从线性粘弹性区向非线性粘弹性区转变的临界应变值不同,且磁场增大可拓宽线性粘弹性区的范围；在线性粘弹性区磁流变胶泥对0~80 Hz频率无依赖性.%Elasticity cement consisting of high viscosity linear polysiloxane based magnetorheological elasticity cement (MEC)with 20%,40% and 60% weight fraction of carbonyl iron powder were prepared.Magnetorheo-logical rheological properties and dynamic mechanical properties were systematically tested.The constitutive re-lation and parameters of MEC were identified.The relationship of viscoelastic properties with magnetic field,i-ron powder content,shear strain and shear frequency were analyzed.The results demonstrated that the consti-tutive relation of MEC can be described using a Herschel-Bulkley model.The shear stress and stiffness of MEC with 60% weight fraction of carbonyl iron powder can be controlled by magnetic field with a wide range (for ex-ample,adjustable range of shear stress was from 16 kPa to 128 kPa,adjustable range of storage modulus was from 0.52 MPa to 3.28 MPa).The shear stress increased,the elasticity increased and the viscosity decreased with the iron mass fraction and magnetic field increasing.The critical strain,which was from the linear viscoe-lastic region to nonlinear viscoelastic area,was different at various magnetic field.The range of the linear visco-elastic region can be broaden with the magnetic field increasing.Magnetorheological elasticity cement was inde-pendent of frequency (0-80 Hz)in the linear viscoelastic range.
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