烧结温度对纳米复相SmFeO_3/γ-Fe_2O_3材料组织结构及磁性的影响  

Effect of Sintering Temperature on the Microstructure and Magnetic Properties of SmFeO_3/γ-Fe_2O_3 Nanocomposites

作　　者：林超[1] 盛晓波[1] 董寅生[1] 储成林[1] 郭超[1] 

机构地区：[1]东南大学材料科学与工程学院江苏省先进金属材料高技术研究重点实验室,江苏南京211189

出　　处：《磁性材料及器件》2009年第6期15-18,共4页Journal of Magnetic Materials and Devices

摘　　要：采用溶胶-凝胶法制备了纳米晶SmFeO3/γ-Fe2O3复合粉体,然后经压制和高温烧结制备了SmFeO3/γ-Fe2O3块体样品。研究了烧结温度对样品组织结构与磁性能的影响,结果表明,干凝胶经450℃预烧后,粉体样品中出现SmFeO3相,但仍有部分非晶相存在。烧结温度对块体材料晶粒尺寸及磁性能有着显著的影响,在保温时间为1h的情况下,当烧结温度从800℃升高到1100℃时,烧结块体中SmFeO3和γ-Fe2O3两相的平均晶粒尺寸分别由51nm和48nm长大到79nm和76nm,样品致密度由56%增大到72%,比饱和磁化强度从51A.m2/kg升高到76A.m2/kg,矫顽力从215kA/m下降到187kA/m。SmFeO3/γ-Fe2O3 nano-powder was prepared by sol-gel method, and then the bulk magnet samples were fabricated by suppression molding and sintering. The influence of sintering temperature on microstructures and magnetic properties of the samples were investigated. The experimental results indicated that the SmFeO3 phase is formed after xerogels are preheated at 450℃, however, there are still some amorphous phase in the sample. The sintering temperature has a significant influence on the grain size and the magnetic properties of the nano-composite. When increasing the sintering temperature from 800℃ to 1100℃ for 1 h, the average grain size of SmFeO3 and γ-Fe2O3 increases from 5 lnm to 79nm and 48nm to 76nm, respectively, the relative density of the samples increases from 56% to 72%, and the saturation magnetization of the samples increases from 5 1A·m2/kg to 76A·m2/kg while the coercivity force decreases from 215kA/m to 187kA/m.

关 键 词：SmFeO3/γ-Fe2O3复合磁体 溶胶-凝胶法 烧结温度 纳米晶 结构 磁性能 

分 类 号：TM273[一般工业技术—材料科学与工程]