Addressing the contradiction between the magneto-rheological properties and dispersion stability of MRFs poses a significant challenge in the preparation process. This paper proposes a micro-nano composite material design scheme using graphene oxide as a grafting agent to encapsulate nanoscale magnetite (FeO) particles onto the surface of carbonyl iron powders. The prepared micro-nano composite magnetic microspheres achieve a reduction in density for enhanced stability while ensuring no compromise in magnetic performance. The effectiveness of the preparation process is ensured through the analysis of the microscopic morphology, crystal structure, and elemental characteristics of all process products using Field Emission Scanning Electron Microscopy (FE-SEM), powder X-ray diffraction (XRD), Raman Spectroscopy, and Fourier Transform Infrared Spectroscopy (FTIR). To obtain MRFs more suitable for magneto-rheological damper applications, this study synthesized micro-nano composite MRFs with different base liquids and varying volume fractions. The stability and magneto-rheological properties of each sample were analyzed through visual techniques and rheological testing platforms. The results indicated that micro-nano composite MRFs based on 40% to 50% silicone oil exhibit superior stability in various aspects, including sedimentation stability, redispersion stability, and temperature stability. Additionally, the micro-nano composite MRFs demonstrated significantly enhanced magnetic performance compared to pure micrometer-sized, pure nanometer-sized, and micro-nano hybrid MRFs.

中文翻译：

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氧化石墨烯（GO）修饰微纳复合磁性微球的制备及表征

解决MRF的磁流变特性和分散稳定性之间的矛盾对制备过程提出了重大挑战。本文提出了一种以氧化石墨烯为接枝剂，将纳米级磁铁矿（FeO）颗粒封装在羰基铁粉表面的微纳复合材料设计方案。所制备的微纳米复合磁性微球实现了密度的降低，增强了稳定性，同时保证了磁性能不受影响。通过使用场发射扫描电子显微镜（FE-SEM）、粉末X射线衍射（XRD）、拉曼光谱分析所有工艺产品的微观形貌、晶体结构和元素特征，确保制备工艺的有效性。和傅里叶变换红外光谱 (FTIR)。为了获得更适合磁流变阻尼器应用的磁流变体，本研究合成了具有不同基液和不同体积分数的微纳米复合磁流变体。通过视觉技术和流变测试平台分析每个样品的稳定性和磁流变特性。结果表明，基于40%至50%硅油的微纳米复合MRF在沉降稳定性、再分散稳定性和温度稳定性等方面表现出优异的稳定性。此外，与纯微米尺寸、纯纳米尺寸和微纳米混合MRF相比，微纳米复合MRF表现出显着增强的磁性能。