| Nanosized magnetic material is the main domain in material study in future. As an important sort of magnetic materials, MnZn ferrites have a better prospect. The sintering and influence of additive on properties of MnZn ferrites nanocrystal were discussed in this paper. We got better sintering system and doping conditions of MnZn ferrites.The MnZn ferrite nanocrystal has been successfully synthesized by a simple synthesis, co-precipitation phase transformation. The green body was sintered by different sintering process, the segmented sintering process and the two steps sintering process. The physical and magnetic properties of sintered compacts were measured by X-ray diffraction (XRD), scanning electron microscopy (SEM), Nim2000 testing system of magnetic material and vibrating sample magnetometer (VSM), respectively.To the segmented sintering process, the results show that the density and grain size of sintered compacts increase with the rising of the sintering temperature and the magnetic properties of sintered compacts also increase with the rising of the sintering temperature. The better sintered temperature is 850℃, its density is 4.30g/cm3. To avoid the abnormal grain growth of sintering process, the two steps sintering is used. The sintering temperature rises to a higher temperature first. Then it lowers to an exact temperature and remains for some time. As a result, the abnormal grain growth is not occurred in the sintering process.The key technology for MnZn ferrite is to add in proper content dopants and sintered under optimal sintering condition. The influence of SiO2 on the magnetic properties of MnZn ferrite is studied. The results show that the magnetic property is improved and the proper content is 0.005%.
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