Synthesis and characterization of Nd doped M-type hexagonal barium ferrite ultrafine powders

来源期刊：中南大学学报(英文版)2001年第2期

论文作者：GUO Rui-qian LI Hong-gui SUN Pei-mei LI Yun-jiao ZHAO Zhong-wei LIU Mao-sheng

文章页码：130 - 134

Key words：sol-gel method; rare earth element; permanent ferrite; citrate; ultrafine powder

Abstract: The hexagonal BaNdxFe12-xO19(x=0.1-1·0) fine powders with M-type structure were synthesized by sol-gel auto-combustion high-temperature synthesis method. The structure of powders, gels′combustion and magnetic properties of powders were respectively studied by means of X-ray diffractometer (XRD),differential thermal analysis-thermogravimetric analysis (DTA-TG) and vibratingsample magnetometer (VSM).The powders before and after combustion and calcination at 450-850℃with different mole ratio of Nd to Ba(0.1-1.0) were compared in terms of XRD. In addition, the effects of different synthesis conditions on magnetic properties of powderswere also discussed. The results show that at pH7.0 or so, mole ratio of citrate to nitrate (1-3) and calcination temperature of 850℃for1 h, M-type BaNd_xFe_12-xO₁₉(x=0.1-1.0) fine powders can be obtained, and the coercive force reaches 436880 A·m-1atx=1, which is fargreaterthan that ofbarium permanent ferrite (BaFe₁₂O₁₉).