The Research Of Fabrication Of Mnzn Ferrite Nano-magnetic By High-energy Grinding

As a multi-functional material,MnZn ferrite nano-magnetic material,are widely used in communication devices and a variety of switching power converters.It has become a promising magnetic material in the field of high-frequency.Compare with other materials,it has a lot of advantages,such as high initial permeability,high saturation magnetic induction and low coercivity.Therefore,its fabrication method has attracted attention of scientists around the world.Nowadays,the fabrication methods of nanometer magnetic material mainly include high-energy grinding method,chemical precipitation method,thermal decomposition method and so on.Nanometer material is commonly fabricated because of its simple process,low cost,high efficiency.The work of this paper includes the influence of the preparation MnZn ferrite on its magnetic.The working principle of high energy grinding is mainly through the grinding and collision of the grinding medium and material.The grinding effect of the material is closely related to many factors,including grinding speed,medium ratio,grinding time and so on.In this paper,the ooptimum parameters of the process of preparing MnZn ferrite were studied by using the control variable method.Then,prepare the magnetic fluid of MnZn ferrite by high energy grinding method,and the best parameters were got by the conclusion,that influence fabrication of MnZn ferite nanometer magnetic.The works of the paper are as follows:(1)Based on the relationship between the composition of MnZn ferrite and the initial magnetic permeability,and the magnetic theory of MnZn ferrite,the experimental results show which formula make the initial permeability of MnZn ferrite is the highest.(2)Proper amount of dopnant can improve the magnetic properties of MnZn ferrite.In this paper,the effects of SiO2,Bi2O3,Nb2O5 single doping and co-mplex doping on the magnetic properties of MnZn ferrite were studied.The con-clusion is that the maximum factor of MnZn ferrite initial permeability is with-in the process experiment,the order is SiO2,Bi2O3 Nb2O5,figure out the best formula.(3)With the second grinding milling time increasing,can effectively reduce the particle size of powder.Then,the conclusion of secondary milling time was figured by sample density,powder particle size and sample morphology.Figure out the secondary milling time.(4)Compare with the particle size,viscosity and saturation magnetization of the sample under different process conditions by controlling the variable method.Figure out the final dispersant,the medium pellet,the ratio and the milling time.The MnZn ferrite magnetic fluid prepared by mechanical method has the advantages of uniform and good sample structure,high stability and high saturation magnetization.It can be proved that the mechanical preparation of MnZn ferrite magnetic fluid is not only feasible but also effective.