Magnetorheological fluid (MRF)-based rotating torque transmission devices are gaining popularity such as MR brake and MR clutch. The effectiveness of the developed devices reduces due to thermal thinning behavior such as a decrease in strength at high temperature of MRF. To design MR devices such as MR clutch and MR brakes, it is necessary to maintain the strength of MRF at the higher temperature. Since MRF is the main component of MR devices, the synthesis of good quality MRF is a prime concern. In this research article, the role of graphite flakes on the strength of MRF at high temperature and its rheology is investigated. In this article, the effectiveness of graphite flakes is tested on MRF by selecting different weight fractions. MRF and MRF with graphite flakes (MRFG) have been synthesized with carbonyl iron particles (80 wt%) and graphite flakes (0.5, 1, 2, 3, 4, and 5 wt%). MRF and MRFG are characterized or evaluated by the rheometer. The rheological properties of MRF and MRFG have been examined using rotational tests. Results show the effective use of graphite flakes in MRF. MRFG has a higher value of shear stress than the MRF at high temperature and shear rate.

中文翻译：

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石墨薄片对高温磁流变流体强度及其流变学的影响

基于磁流变液 (MRF) 的旋转扭矩传输装置越来越受欢迎，例如 MR 制动器和 MR 离合器。由于热变薄行为，例如 MRF 在高温下的强度降低，所开发器件的有效性会降低。为了设计MR离合器和MR制动器等MR器件，需要在较高温度下保持MRF的强度。由于 MRF 是 MR 设备的主要组成部分，因此合成高质量的 MRF 是首要问题。在这篇研究文章中，研究了石墨薄片对高温下 MRF 强度的作用及其流变学。在本文中，通过选择不同的重量分数，在 MRF 上测试了石墨薄片的有效性。MRF 和带有石墨片 (MRFG) 的 MRF 已经用羰基铁颗粒 (80 wt%) 和石墨片 (0.5, 1, 2, 3, 4, 和 5 wt%) 合成。MRF 和 MRFG 由流变仪表征或评估。MRF 和 MRFG 的流变特性已使用旋转测试进行了检查。结果表明石墨薄片在 MRF 中的有效利用。MRFG 在高温和剪切速率下具有比 MRF 更高的剪切应力值。