Magnetorheology of a magnetic fluid based on Fe3O4 immobilized SiO2 core-shell nanospheres: experiments and molecular dynamics simulations
Magnetorheology of a magnetic fluid based on Fe3O4 immobilized SiO2 core-shell nanospheres: experiments and molecular dynamics simulations
复制标题
基于 Fe3O4 固定 SiO2 核壳纳米球的磁流体的磁流变：实验和分子动力学模拟
DOI：
10.1039/c6ra28436a
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发表时间：
2017
期刊：
影响因子：
3.9
通讯作者：
Xuan Shouhu
中科院分区：
文献类型：
--
作者：
Pei Lei;Pang Haoming;Ruan Xiaohui;Gong Xinglong;Xuan Shouhu
研制了一种基于fe3o4 -固定化二氧化硅纳米球（MSiNPs）的超顺磁磁流体。通过实验分析和计算模拟对其磁流变特性进行了研究。与纯Fe3O4基磁流体相比，MSiNPs基磁流体的磁流变效应约大25倍。为了证明力学性能的提高，提出了一个改进的磁偶极模型来描述两个紧密磁化粒子的磁相互作用。此外，还进行了分子动力学模拟，以了解外加磁场作用下的微观结构演变。模拟结果表明，在稳态状态下形成链状和柱状颗粒结构，在稳态剪切流动中转变为片层状微观结构。粒子级模拟结果与实验数据吻合良好。基于MSiNPs的磁流体磁致共振效应的显著增强源于磁感应强度和颗粒结构的大小。
A novel superparamagnetic magnetic fluid based on Fe3O4-immobilized-SiO2-nanospheres (MSiNPs) was developed. Both the experimental analyses and computational simulations were conducted to investigate its magnetorheology. In comparison to the pure Fe3O4 based magnetic fluid, the magnetorheological (MR) effect of the MSiNPs based magnetic fluid was about 25 times larger. To demonstrate the improving mechanical properties, a modified magnetic dipolar model was proposed to describe the magnetic interaction of two close magnetized particles. Moreover, the molecular dynamic simulations were carried out to understand the microstructure evolution under an applied magnetic field. The simulation results showed that chain-like and column-like particulate structures were formed in the stationary state and transferred into lamellar microstructures in the steady shear flow. Particle-level simulations were in good agreement with experimental data. The dramatic increase in MR effect of the MSiNPs based magnetic fluid originated from the intensity of the magnetic attractions and the size scale of the particulate structures.