超细六角铁酸钡的分散与磁场下成型研究  

Research on Dispersion and Molding in Magnetic Field of Ultrafine Hexagonal Barium Ferrite Powders

作　　者：王梦瑜[1] 

机构地区：[1]杜兰大学物理学院

出　　处：《合肥师范学院学报》2011年第3期26-31,共6页Journal of Hefei Normal University

摘　　要：本文采用溶胶凝胶自燃烧法制备了粒径在200~300nm的单相六角铁酸钡粉体,并对其进行球磨,外加PEG-20000为分散剂,调节料浆的pH值等手段对六角铁酸钡磁性颗粒进行分散,研究表明球磨过程中磁性颗粒经历了团聚后打开,然后有形成诸如磁链、磁环等磁结构的过程。对六角铁酸钡进行干压（未加磁场和加磁场）以及磁场下悬浮-沉降等工艺成型,经过压力和磁场的作用得到的块材沿易磁化方向具有一定的取向。磁性测试结果表明：球磨前后的粉体比磁化强度（1.5T）从40.3emu/g上升到了51.5emu/g,这个数值接近铁酸钡单晶磁化强度,矫顽力从4.1kOe小幅度提高到4.3kOe。悬浮-沉降成型比磁化强度（1.0T）就达到了48.4emu/g,而矫顽力有明显下降。Ultrafine M-BaFe12O19 powders with high phase purity were synthesized through sol-gel auto-combustion process,which have an average particle size of 200~300nm.Surfactant-assisted（PEG-20000） ball milling of BaFe12O19 ferrite dispersion,with adjusting the PH of the slurry,indicates that the aggregate particles in the slurry disperse and then form a chain or circle.The slurry with pH=4,PEG which is 10% of the slurry and 8~10 hours of ball milling,shows a relatively fine dispersion.With dry-press and suspension-sedimentation under magnetic field,the orientation of the block material is along with orientation of easy-magnetization axis with the effect of pressure and magnetic field.The result of the test of magnetism indicates that specific magnetization intensity（1.5T） rise from 40.3emu/g to 51.5emu/g after ball milling,which approaches to the intensity of magnetization of mono-crystalline hexagonal barium ferrite,and coercive force has risen from 4.1kOe to 4.3kOe.The specific magnetization intensity（1.0T） of suspension-sedimentation molding has reached 48.4emu/g,but coercive force has obviously fallen.

关 键 词：六角铁酸钡 分散 磁场成型 

分 类 号：TM271[一般工业技术—材料科学与工程]