Häßner Manuel, Vinnik Denis A, Niewa Rainer
University of Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart, Germany.
South Ural State University, Lenin's Prospect 76, 454080 Chelyabinsk, Russia.
Materials (Basel). 2020 Feb 13;13(4):858. doi: 10.3390/ma13040858.
Single crystals of aluminum substituted strontium hexaferrite SrFeAlO were grown from sodium oxide based flux. The substitution level aimed for was = 1.2. Annealing experiments performed on single crystals show that the Al distribution on the five iron sites of the hexaferrite structure depends on the annealing time at 900 °C. Single crystal X-ray diffractometry shows that annealing a crystal after the initial synthesis has an impact on the Al content on the octahedrally and tetrahedrally coordinated sites. Furthermore, it was found that heating in a corundum crucible increases the overall Al content. Magnetic measurements show that annealing in a platinum or corundum crucible decreases coercivity and remanence while the saturation magnetization is hardly influenced.
采用基于氧化钠的助熔剂生长出了铝取代的六方铁酸锶单晶SrFeAlO。目标取代水平为 = 1.2。对单晶进行的退火实验表明，六方铁氧体结构中五个铁位点上的铝分布取决于900℃下的退火时间。单晶X射线衍射法表明，初始合成后对晶体进行退火会影响八面体和四面体配位位点上的铝含量。此外，还发现，在刚玉坩埚中加热会增加铝的总含量。磁性测量表明，在铂坩埚或刚玉坩埚中退火会降低矫顽力和剩磁，而饱和磁化强度几乎不受影响。
