Abstract The microstructures, magnetic and electronic performance of NiZnCu ferrites have been investigated at temperature from 850 °C to 1000 °C. X-ray diffraction (XRD) patterns showed that only single phase with spinel structure existed. Scanning electron microscopy (SEM) results showed that grain size increased with enhancement of sintering temperature and the most homogeneous, compact microstructure was obtained at 950 °C. Magnetic properties measurements revealed that both complex permeability and saturation magnetization increased with increasing of sintering temperature. The initial permeability was approximately linear within the scope of 850–1000 °C as well as the resonance frequency decreased from 70 MHz to 30 MHz. Power loss density tests demonstrated that the core sintered at 950 °C instead of the one sintered at 1000 °C had the lower power loss density at both 5 mT and 10 mT and the higher inductance under a certain exciting direct current at 1 MHz. Also the inductance of the sample sintered at the higher temperature dropped faster than that at the lower temperature. The results showed that the core sintered at 950 °C had better electrical performance and was suitable for wide usage.

中文翻译：

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烧结温度对使用 NiZnCu 铁氧体的环形磁芯性能的影响，用于 >1 MHz 的功率应用

摘要 研究了 NiZnCu 铁氧体在 850 °C 至 1000 °C 温度范围内的微观结构、磁性和电子性能。X 射线衍射 (XRD) 图案表明仅存在具有尖晶石结构的单相。扫描电子显微镜 (SEM) 结果表明，晶粒尺寸随着烧结温度的升高而增加，并且在 950 °C 时获得了最均匀、致密的微观结构。磁性能测量表明复磁导率和饱和磁化强度都随着烧结温度的增加而增加。初始磁导率在 850-1000 °C 范围内近似线性，共振频率从 70 MHz 降低到 30 MHz。功率损耗密度测试表明，在 950 °C 下烧结的磁芯比在 1000 °C 下烧结的磁芯在 5 mT 和 10 mT 下的功率损耗密度更低，并且在 1 MHz 的一定励磁直流电流下具有更高的电感。此外，在较高温度下烧结的样品的电感比在较低温度下的下降得更快。结果表明，950°C烧结的磁芯具有更好的电气性能，适合广泛使用。