Study On Preparation,Microstructure And Magnetic Properties Of RE Elements Doped M Type Strontium Ferrites

M-type permanent magnet ferrite is an indispensable functional material in today's society.Because of its excellent magnetic properties and high performance-to-price ratio,M-type permanent magnet ferrite firmly occupies most of the permanent magnetic material market.With the vigorous development of intelligent office equipment and household appliances,the development of M-type permanent magnet ferrite has been further improved,and the magnetic properties of M-type permanent magnet ferrite have higher requirements.This is an opportunity and challenge for the development of permanent magnet ferrite.Ion substitution is a very effective method to improve M-type permanent magnet ferrite.In this paper,the effects of different ion substitutions on the structure and magnetic properties of M type permanent magnet ferrite are studied in detail,which is of great significance to the research and development of high performance M type permanent magnet oxygen.M-type strontium permanent magnet ferrites doped with Y-Co,Y-La-Co and Ce-Zn ions were prepared by conventional solid-state reaction method.The experimental results are as follows:1.Y-Co doped strontium ferrite Sr0.95Y0.05Fe12-xCoxO19(x=0.00,0.08,0.16,0.24,0.32,0.40)was prepared by solid state reaction.The microstructure and magnetic properties of the samples were studied in detail.XRD results showed that the pure phase of M-type strontium permanent magnet ferrite could be obtained when the doping amount was appropriate.When the doping amount is excessive,the ?-FezO3 miscellaneous begins to appear.The lattice constant a of the substituted sample is almost unchanged.The lattice constant c shows a trend of increasing with the increase of doping content.The structure of SEM shows that all the samples have hexagonal flake structure.And the particle size and distribution are more uniform.The magnetic properties of the sample are studied by VSM.The experimental results show that the Y-Co doping can improve the magnetic properties of M-type permanent magnet ferrite to a certain extent when the doping content is in a proper range.2.Y-La-Co doped M-type permanent magnet ferrite Sr0.95-xY0.0sLaxFe11.75Co0.25O19(x=0,0.1,0.2,0.3,0.4)was prepared by conventional solid-state reaction.The XRD results showed that the pure phase of M-type strontium permanent magnet ferrite could be obtained when the doping amount was not more than 0.3.When ?-Fe2O3 is more than 0.3,?-Fe2O3 begins to appear.The lattice constant a of the doped sample is almost unchanged.The lattice constant c shows a decreasing trend with the increase of doping content.The results of scanning electron microscopy(SEM)show that all the samples have formed hexagonal lamellar structure.The sample size is more uniform.The results of the vibratory sample magnetometer(VSM)show that Y-La-Co doping can effectively enhance the comprehensive magnetic properties of M-type permanent magnet ferrite under appropriate conditions.3.Ce-Zn doped M-type permanent magnet ferrite Sr1-xCexFe12-xZnxO19(X=0,0.1,0.2,0.3,0.4,0.5)was prepared by solid state reaction method.The effect of doping amount on the microstructure and magnetic properties of the samples was studied in detail.The results of XRD showed that the pure phase of oxygen of M-type strontium permanent magnet could be obtained when the doping amount was within the appropriate range.When the doping amount exceeds a suitable value,?-Fe2O3 will appear in the XRD spectra of the sample.The results of scanning electron microscopy(SEM)show that all the samples have formed hexagonal flake structure.The size and distribution of the particles are uniform.The magnetic properties of the samples show saturation magnetization(Ms)and coercivity(Hc).The results of this experiment show that the doping of Ce-Zn can improve the magnetic properties of M-type strontium permanent ferrite in a certain range.