Mn-Zn Ferrite의 소결조건이 미세조직 및 자기특성에 미치는 영향

Abstract

The effects of sintering temperature and sintering atmosphere on magnetic properties and microstructuresof Mn-Zn ferrites have been studied. Mixture of 52.8mole% Fe2O3, 26.4mole% MnO, 15.1mole0% ZnO and 5.7mole% NiO was prepared, and 0.1mole% CaO, 0.02mole% $SiO2 were added as minor additives. After calcining and ball milling the powder was granulated for compacting. The specimens were sintered at $1, 250^{\circ}$, $1, 300^{\circ}$and 1, 350℃ in the various atmosphere of N₂, $N^_2\DIV0.6% O2, $N_2＋2.7% O2, $N_2＋4.1% O2, $N^2＋8.2% O2 and air for 3 hours and cooled in N₂ atmosphere. The grian growth rate and densities increase as sintering temperature and oxygen content of atmosphere increase. At the sintering temperature of 1, 250℃ the initial permeabilities increase as oxygen content of atmosphere increase. At the sintering temperature of$ 1, 300^{\circ}$and $1, 350^{\circ}$ the initial permeabilities show maximum values at $N_2＋4.1% O2 atmosphere. The secondary peaks of initial permeabilities are observed between 100oand 200℃, and the positions of secondary peaks move to higher temperature as oxygen content of atmosphere increases. Q-factors decrease as sintering temperature increases and oxygen content of atmosphere decreases.