摘要:
本文采用固相反应法制备了掺杂M型钡铁氧体BaFe10.2Sc1.8O19，并对其在烧结过程中的相变及磁性质做了一定的研究。结果表明，当烧结温度低于1000℃时，尖晶石相BaFe2O4和铁离子缺失的M型铁氧体是主要的烧结产物。当烧结温度高于1050℃时，M型铁氧体BaFe10.2Sc1.8O19开始生成。直到当烧结温度达到1200℃时，BaFe10.2Sc1.8O19才以单相的形式存在于烧结产物中。随着烧结温度的升高，烧结产物的剩磁比和矫顽场逐步降低，并在烧结温度高于1200℃的时候降到接近于零。饱和磁化强度随着烧结温度的升高逐步升高，并在1050℃的时候达到最大值，随后逐渐降低。磁性质的变化过程与烧结产物的相变是一致的。以上结果表明，相对于Fe3+，Sc3+对M型铁氧体的掺杂需要更高的热能，并会导致M型铁氧体磁性质的较大变化。
Abstract:
Sc doped M-type hexaferrite BaFe10.2Sc1.8O19 was prepared with the conventional solid state reaction method. The phase and magnetic property transition processes in the sintering process of M-type hexaferrite BaFe10.2Sc1.8O19 have been investigated. Results show that the spinel phase BaFe2O4 and ion-deficient M-type hexaferrite dominate when sintering temperature is lower than 1000˚C. The M-type hexaferrite BaFe10.2Sc1.8O19 appears above 1050˚C and does not become a single phase until 1200˚C. Both the remanence ratio and coercivity of the samples decrease with increasing sintering temperature and drop to nearly zero above 1200˚C. However, the saturation magnetization of the samples increases with increasing sintering temperature until 1050˚C and then decreases. The magnetic property transition process agrees well with the phase transition process. The above results show that incorporation of Sc3+ into the M-type hexaferrite needs a higher thermal energy than that of Fe3+, and will lead to a drastic change in the magnetic properties of M-type hexaferrite.