Two different shapes of spherical- and flake-like soft-magnetic carbonyl iron (CI) microparticles were dispersed in silicone oil to prepare magnetorheological (MR) fluids. The magnetic-field dependent rheological behaviors of the MR fluids were scrutinized focusing on their shape effect. Saturation magnetization of the flake-shaped CI was obtained to be slightly lower than that of spherical-shaped CI. However, rheological properties of shear stress, shear viscosity, and storage modulus of the flake-shaped CI MR fluid surpassed those of the spherical-shaped CI MR suspension under applied magnetic field strengths. The flake-shaped CI based MR fluid also demonstrated superior sedimentation stability compared with the spherical-shaped CI. This was due to large surface area, suggesting that the anisotropy of CI particles plays an important role in their MR performance.

中文翻译：

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形状不同的羰基铁微粒的磁流变特性

将两种不同形状的球形和片状软磁羰基铁（CI）微粒分散在硅油中以制备磁流变（MR）流体。仔细研究了MR流体与磁场有关的流变行为，重点研究了它们的形状效应。片状CI的饱和磁化强度略低于球形CI的饱和磁化强度。但是，在施加磁场强度下，片状CI MR流体的剪切应力，剪切粘度和储能模量的流变特性超过了球形CI MR悬浮液的流变特性。与球形CI相比，片状CI基MR流体还显示出优异的沉降稳定性。这是因为表面积大，