料粉振磨处理在各向异性干压永磁铁氧体中的应用

Application of vibrating ball milling of powder for anisotropic dry-press permanent ferrite

以高性能的预烧料为原料,采用有别于传统制造干压料粉的工艺,通过对细磨烘干后的料粉进行振磨处理,制备各向异性干压永磁铁氧体材料。结果表明,料粉的振磨处理减少了料浆在高温烘干时不可避免出现的粉体颗粒间的粘连,提高了粉体的分散性,有利于取向成型时粉体颗粒在磁场中的转动,进而提高了干压成型体的取向度和密度。典型干压磁体磁性能为:剩磁B_r=404mT、矫顽力H_(cb)=283kA/m、内禀矫顽力H_(cj)=317kA/m、最大磁能积(BH)_(max)=30.4kJ/m^3。

Anisotropic dry-pressed hard ferrite was prepared from fine drying pre-sintered ferrite powders treated with vibrating ball milling,different from traditional manufacturing process to improve the orientation degree and density of dry-pressed magnets.The result shows that vibration grinding process after the fine grinding and drying of powders reduces the adhesion of powder particles brought inevitably during high temperature drying of slurry,which is beneficial to the rotation of powder particles in orientation magnetic field.The magnetic properties of typical dry-pressed magnet are as follows:Br=404mT,Hcb=283kA/m,Hcj=317kA/m,(BH)max=30.4kJ/m3.