Faculty of Physics, Lomonosov Moscow State University, 119991 Moscow, Russia.
Helmholtz-Zentrum Dresden-Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany.
Int J Mol Sci. 2019 Mar 22;20(6):1457. doi: 10.3390/ijms20061457.
We present the results of numerical simulation of magnetodielectric effect (MDE) in magnetorheological elastomers (MRE)-the change of effective permittivity of elastomer placed under the external magnetic field. The computer model of effect is based on an assumption about the displacement of magnetic particles inside the elastic matrix under the external magnetic field and the formation of chain-like structures. Such displacement of metallic particles between the planes of capacitor leads to the change of capacity, which can be considered as a change of effective permittivity of elastomer caused by magnetic field (magnetodielectric effect). In the literature, mainly the 2D approach is used to model similar effects. In this paper, we present a new approach of magnetorheological elastomers simulation-a 3D-model of the magnetodielectric effect with ability to simulate systems of 10 5 particles. Within the framework of the model, three types of particle size distributions were simulated, which gives an advantage over previously reported approaches. Lognormal size distribution was shown to give better qualitative match of the modeling and experimental results than monosized type. The developed model resulted in a good qualitative agreement with all experimental data obtained earlier for Fe-based elastomers. The proposed model is useful to study these novel functional materials, analyze the features of magnetodielectric effect and predict the optimal composition of magnetorheological elastomers for further profound experimental study.
我们展示了磁流变弹性体（MRE）中磁电效应（MDE）数值模拟的结果——在外磁场作用下弹性体有效介电常数的变化。该效应的计算机模型基于在外磁场作用下磁性颗粒在弹性基体中的位移假设和链状结构的形成。这种金属颗粒在电容器极板之间的位移导致电容的变化，这可以被认为是磁场引起的弹性体有效介电常数的变化（磁电效应）。在文献中，主要使用二维方法来模拟类似的效应。在本文中，我们提出了一种新的磁流变弹性体模拟方法——具有模拟 105 个粒子系统能力的三维磁电效应模型。在模型框架内，模拟了三种粒径分布类型，这比以前报道的方法具有优势。对数正态分布的模拟结果与实验结果具有更好的定性匹配，优于单尺寸类型。所提出的模型与先前为 Fe 基弹性体获得的所有实验数据在定性上吻合较好。所提出的模型对于研究这些新型功能材料、分析磁电效应的特征以及预测磁流变弹性体的最佳组成以进行进一步深入的实验研究非常有用。
