镝钴铁氧体磁流体的制备与性质研究(英文)

Study of preparation and modification for Dysprosium Cobalt Ferrite Magnetic Fluids

为了提高磁流体的抗氧化能力 ,我们采用化学共沉淀———超声波分散法制备了镝钴铁氧体磁流体 ,用Dy3 + 取代Co2 + 进行改性。利用古埃磁天平研究了温度、稀土镝改性、表面活性剂的表面改性、超声波分散时间对其磁性和稳定性的影响 ,并从理论上进行了分析。X射线衍射谱(XRD)、透射电镜 (TEM)对制得的磁粒子组成、结构及粒径进行了分析。提高熟化温度 ,添加适量的镝有利于磁化强度的提高。

In order to improve the resistivity of oxidation,dysprosium cobalt ferrite magnetic fluids were prepared by precipitation-sonication.Dysprosium modification is carried out replacing Co 2+ with Dy 3+ .Influences of temperature,amount of dysprosium and mechanism of surface modification on the magnetic properties and stability have been studied through a measurement device based on Gouy magnetic balance.X-ray diffraction (XRD) and transmission electron microscopy (TEM) are utilized to analyze the phase,structure and sizes of the magnetic particles.In addition,effects of ultrasonic time on the stability of dysprosium cobalt ferrite magnetic fluids were also investigated in this study.Studies have shown that improving the curing temperature and adding the proper amount of Dy 3+ will increase the magnetic property for magnetic fluids.