| M-type ferrite is applied more and more widely, have an important role in the field of home appliances, computers, office equipment. Along with the rapid development of electronic information and electrical automation, magnetic materials also ushered in a development opportunity. The magnetic material needed by society is the goals of magnetic materials workers. The community still needs low cost and excellent performance, durable magnetic products.so the low cost is the pursuit of every business.This paper is completed in Magnetic Materials Engineering Technology Research Center of Anhui Province, relying on advanced laboratory equipment and testing devices, by carrying out a series of experiments with the excellent experimental materials. Preparation of strontium ferrite sample in this experiment is in the traditional ceramic method and wet molding method. The M-type strontium ferrite samples obtained is anisotropic.By changing the calcining temperature, adding the secondary additives and adjusting the milling process, impact on the structure and magnetic performance of the M-type strontium ferrite materials prepared is studied. In the experiments, the test device SY-8258produced by Iwasaki in Japan for magnetic properties of permanent ferrite, scanning electron microscopy (SEM), X-ray diffraction (XRD) and other advanced equipment are applied, body samples were related to expression. Experimental research results obtained are as follows:1. Fewer impurities and better morphology pre-sintered material is selected by analysis equipment.2. The secondary additives alone of CaCO3, Al2O3, H3BO3, sorbitol is added during the experiment. The impact on Magnetic properties of magnetic materials is analyzed, the most appropriate range of the secondary additives added is determined: CaCO3addition in the range of0.7to0.9wt%, Al2O3addition within the range of0.3to0.5wt%, H3BO3addition within the range of0.2to0.4wt%, SiO2addition in the range of0.2to0.3wt%.3.In the preparation process, how the milling time and milling method affect the phase structure and magnetic properties of samples is researched, experiments results show that the magnetic performance is the best when the samples are milled for five hours.The roller ball milling effect is much better than a planetary ball milling,the former remanent magnetization of the former is higher10-20mT than the latter one,the coercivity Hcj-improves15～20kA·m-1.4.By changing the sintering temperature,the impact on the phase structure of the samples prepared at different sintering temperatures is studied,the residual magnetization Br and intrinsic coercivity Hci, the experimental results show that when heated to1234℃, the magnetic properties of the samples obtained is optimal.5. By adding a separate secondary additives, the optimal amount of secondary additives is determined. The secondary additives:CaCO3, Al2O3, H3BO3, SiO2and sorbitol are choosed, and then orthogonal experiment by adding the second additive is done, the amount of the secondary additives is determined. CaCO3addition is0.8wt%,Al2O3amount is0.3wt%, H3BO3amount is0.2wt%,SiO2amount is0.3wt%, sorbitol addition amount is0.7wt%,by this way, the magnetic properties by ceramic method can be very prominent, the magnetic properties of the samples abtained: remanent magnetization410.2mT, the intrinsic coercivity316.0kA·m-1,the maximum energy product (BH)max31.8kJ·m-3,they are measured by the Beijing Institute of Metrology.6.The X-ray diffraction (XRD) and scanning electron microscopy (SEM) are applied to express the phase structure and morphology of the hexagonal strontium ferrite prepared. |
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