Preparation method of permanent magnetic ferrite

Abstract

The invention relates to a preparation method of permanent magnetic ferrite. The preparation method comprises the following steps of: burdening; mixing; pelletizing and pre-sintering; crushing; forming; sintering; and cooling to obtain the permanent magnetic ferrite. Through selecting raw materials, optimizing a technological parameter, such as controlling a pulverizing process, controlling a forming parameter, controlling a sintering schedule, controlling a cooling process, and the like in a preparation process, particularly, controlling ball-milling and secondary ball-milling process parameters, the residual magnetism Br of sintered ferrite is not less than 500mT, the coercive force Hcb of the sintered ferrite is not less than 310kA / m, the intrinsic coercive force Hcj of the sintered ferrite is not less than 410kA / m, and the maximum magnetic energy product (BH)max of the sintered ferrite is not less than 35kJ / m<3>.

Description

technical field

[0001] The invention relates to a preparation method for improving the comprehensive performance of permanent magnet ferrite. Background technique

[0002] With the rapid development of the automobile industry, high-performance automobile motors have higher and higher requirements on the performance of permanent ferrite. In order to meet the market demand, in recent years, after the Japanese TDK company, the ace company in the ferrite industry, launched the FB9 and FB12 series of high-performance permanent magnet ferrite products, there has been a rapid development of high-tech ferrite companies in the global ferrite industry. Performance permanent ferrite boom. Various manufacturers have explored ways to improve the magnetic properties of permanent ferrites from the aspects of raw materials, secondary additions, and production processes. The microstructure characteristics of high-performance permanent ferrite materials are: the crystal grains are small and...