Effect of Cyclic Deformation on Magnetorheological Elastomers

采制备了铁颗粒含量分别是60%，70%和80%的三种材料，在应变幅值为50%，75%和100%的循环加载条件下，利用改进后的动态力学分析仪测试了循环加载后材料的储能模量和损耗模量. 结果显示铁颗粒含量为70%和80%的样品，其储能模量和损耗模量都和循环加载的幅值以及循环加载的次数有关，铁颗粒含量为80%样品受加载条件的影响尤其明显. 但铁颗粒含量为60%的样品，其性能却与循环加载的幅值和次数无关. 为了更好的研究磁流变弹性体受循环加载后的性能，样品还进行了准静态拉伸测试，并用扫描电镜对测试的样品进行了原位观察.

Effect of Cyclic Deformation on Magnetorheological Elastomers

Fatigue properties of magnetorheological elastomer (MRE) samples were investigated based on cis-polybutadiene rubber by using a fatigue test machine. Three MRE samples with iron particles mass fraction of 60%, 70%, and 80% were fabricated, and their properties dependence of three strain amplitudes (50%, 75%, and 100%) were measured. The absolute magnetorheological (MR) effect, storage modulus, and loss modulus of MRE samples after fatigue were evaluated by a modified dynamic mechanical analyzer. The results revealed that MR effect, storage modulus, and loss modulus of MREs containing 80% iron particles depended strongly on the strain amplitudes and the number of cycles, while storage mod-ulus and loss modulus of MREs containing 70% iron particles also depended on the strain amplitudes and the number of cycles but not as strongly as sample which contains 80% iron particles, but the properties of MREs containing 60% iron particles after cyclic deforma-tion were almost independent of the fatigued conditions. In order to investigate the fatigue mechanism of MREs, the sample was carried out with a quasi-static tensile testing and its surface morphology during testing was observed in situ by scanning electron microscopy.