Abstract
This study describes the effect of Pr6O11 addition on the magnetic properties and the microstructures of the sintered Mn-Zn ferrite for high frequency power transformer uses. After calcination of mixed raw materials at 1000°C in nitrogen gas, the calcined powders were mixed with Pr6O11 in the concentration ranging from 0 to 0.8wt.% and then compacted. The compacted powders were sintered in air at the various temperatures of 1125-1225°C for 3 hours. When sintered at 1175°C, the coreloss at 50 mT and 200 kHz of sample added with 0.1 wt.% of Pr6O11 decreased to about a quarter of that of the sample without addition. Moreover, the initial permeability of the former sample increased by. about twice that of the latter sample. The fact suggests the formation of Fe2+ ions in the former sample caused by the substitution of Fe3+ ions by added Pr4+ ions.
