NiCuZnフェライトの透磁率の温度特性に及ぼすAl₂O₃添加の影響

抄録

The effects of Al₂O₃ addition on the temperature dependency of initial permeability and microstructure of NiCuZn ferrites were investigated. The temperature dependency of initial permeability decreases as Al₂O₃ addition increases. EPMA analysis revealed that Al₂O₃ dissolves into the grains of NiCuZn ferrite, but the dispersion is not uniform. By separating the initial permeability into the contributions of spin rotation and domain wall motion, it was found that the temperature dependence of the domain wall motion derived part of permeability decreases as Al₂O₃ addition increases, while that of the part derived from spin rotation changes little. This indicates that the decrease of the temperature dependency of initial permeability may be attributed to the influence of Al₂O₃ on the domain wall motion.