Influence Composition Fe2O3 of Isotropic Magnet BaFe12O19 on Microstructure and Magnetic Properties
Abstract
The isotropic magnets Barium Hexsaferit has been made by using a sintering
process and the composition of Fe2O3 on barium hexaferrite was carried by the addition of
Fe2O3 (0, 0:25, and 0.5, % wt). The raw materials were used such as: commercial powder
BaFe12O19 and hematite Fe2O3 from e-Merck. Both the raw materials were weighed according
to the composition, and then refined for 48 hrs by using ball mill. After milling processes, the
mixed powder was measured particle size distribution by using Laser Particle Size Analyzer,
and it was obtained average particle size about 17,15 μm. After that, the powders were mixed
with 2 % white. Celuona WE 518 as a binder, then the sample powders were formed by using
cold pressing with a force about 5 tons becomes pellets with a diameter of 13.10 mm and
thickness of 7.12 mm. Then samples pellet were sintered by using Electrical Thermolyne
Furnace at temperature: 1150 ° C and holding time for 2 hours. The sintered samples were
measured microstructure by using XRD, magnetic properties by using Permeagraph and
Gausmeter. The variation of composition Fe2O3 on barium ferrite can influence significantly on
crystal structure and magnetic properties. It was found two phases such as: BaFe12O19 phase
and Fe2O3 phase on the samples with the addition of 0.5 % Fe2O3, but for sample without the
addition of Fe2O3 and with 0.24% Fe2O3 have only single phase BaFe12O19. The results of
measurement magnetic properties show that Magnet BaFe12O19, with addition 0.25% wt.
Fe2O3 has high value for flux magnetic density and Br, but the Hc value of magnet BaFe12O19
becomes 2 times higher with the addition of 0.5% wt. Fe2O3.