【摘要】 为了研制工艺简单且饱和磁化强度高的磁流体,本文采用化学共沉淀法通过对铁氧体磁流体改性制备了水基镝钕复合铁氧体磁流体,实验讨论了温度、镝与钕的配比及用量、表面活性剂的用量、pH值对磁流体稳定性,改变工艺流程的影响,其结果表明:(1)在n(Fe):[n(Nd3+)+n(Dy3+)]=14:1,n(Fe3+):n(Fe2+)=1.70~1.75,镝与钕的用量比为n(Nd3+):n(Dy3+)=1:1,25%NH3.H2O作为沉淀剂和pH值的调节剂,反应体系温度控制在35℃左右,调pH值至9~11;(2)以明胶作为表面活性剂,其最佳用量是每60 mL载液0.005 0 g,包裹温度在55℃左右,包裹最佳pH=4。该条件下制得黑亮的水基镝钕铁氧磁流体,其磁性能比普通水基铁氧体高。在可见光的照射和磁场的共同作用下,可以看到明亮的磁光环产生。同时,还对产品的黏度、磁化强度、表面包覆情况、稳定性等进行了相应的表征。更多还原

【Abstract】 In this study,We used the chemical co-precipitation method to prepare water-based dysprosium-neodymium ferrite magnetic with higher saturation intensity.The effect on stability of temperature,the amount of dysprosium and neodymium,the amount of surfactant added,the pH were studied.The result showed that:(1) the n(Fe):[n(Nd3+)+n(Dy3+)]=14:1,n(Fe3+):n(Fe2+)=1.70～1.75,the ratio of dysprosium and neodymium is n(Nd3+):n(Dy3+)=1:1,25%NH3·H2O(A.R.) as precipitating agent and pH value conditioner,the reacting system temperature was controlled in 35℃,pH= 9～11 are the optimal condition;(2)the optimal concentration of gelatin is 0.08g/L,the temperature was controlled in 55 ℃ and pH= 4.The magnetism of dysprosium-neodymium ferrite magnetic fluid is higher than common water-base magnetic fluid.It has shined the bright light-ring of magnetism shine,under visible light and acts on magnetic field together.In addition,the characteristics of viscosity,saturation magnetization,surface of the coating and the stability were tested.更多还原