Ferrite-based material as a permanent magnet for components of electrical generators

Perdamean Sebayang, Muljadi Masbah, R T Siregar and Tomi Budi Walyo

  • ANSN Editor
Keywords: nano


A permanent magnet based on ferrite for use as components of electrical generators has been fabricated by two different methods: solid–solid mixing and cooprecipitation. The conventional solid–solid mixing method uses Fe2O3 and BaCO3 as starting materials with mole ratio n=BaO:Fe2O3=1: 6. The mixture is calcinated at 1100 °C and two crystal structures, BaOFe2O3 and BaFe12O19, were obtained with particle size of about 0.5–1.5 μm. Sintering at 1100 °C was followed by a magnetization process. Measurements give the following physical parameter values: remanence, Br=0.0792 T; magnetic saturation, Bs=1.21 T; coersivity, Hc=44.7 kA m-1; density 3.43 g cm-3 and porosity 9.16%. On the other hand, the cooprecipitation method uses FeCl3 and BaCl2 solution with mole ratio n=BaCl2:FeCl3=1:6. After the calcination at 900 °C and higher temperatures a single crystal structure of BaOcenterdot6Fe2O3 is formed with particle size of about 30–60 nm. The optimum sintering temperature for the formation of this single phase crystal structure is 1050 °C. The physical parameters of the final product have the following values: Br=0.2673 T; Bs=1.42 T; Hc=89.4 kA m-1; density 4.34 g cm-3 and porosity 3.36%

Regular articles