钇-镱柘榴石型铁氧体系统的磁性的研究

本文对钇-镱(Y-Yb)柘榴石型铁氧体系统Y_3-xYb_xFe₃O₁₂ (其中x=0,0.75,1.50,2.25和3.00)的磁性进行了研究。采用共同沉淀和氧气中烧结的方法制备样品,进行了X射线粉末照相的观测,测量了静态磁滞迴线,起始磁导率(500千赫),电阻率,鲍和磁化强度,居里点及分米波段磁谱。实验结果表明:整个系统都是单相的柘榴石型结构,所有样品都具有实际密度大(>90％理论密度)、电阻率高(10⁹—10¹⁰欧姆·厘米)的特点。

STUDY OF THE MAGNETIC PROPERTIES OF THE YTTRIUMYTTERBIUM GARNET SYSTEM

The yttrium-ytterbium (Y-Yb) garnet system Y_3-xYb_xFe₃O₁₂ was investigated at the compositions for which x=0, 0.75, 1.50, 2.25 and 3.00. The samples were prepared by the co-precipitation method and sintered 7 hours in oxygen atmosphere at 1350℃ or 1400℃. Lattice constants and theoretical densities were determined from X-ray diffraction data. It was found that the whole system consisted of a single phase with the garnet structure, and the lattice constant decreased linearly from 12.371? (Y₃Fe₅O₁₂) to 12.297? (Yb₃Fe₅O₁₂). The static hysteresis loop, the initial permeability at 500 Kc, the saturation magnetization between liquid-air temperature to the Curie point and the magnetic spectrum between 500 Mc and 3000 Mc were observed as a function of compositions. It was found that all the samples had high bulk densities ( > 90 % theoretical densities) and high resistivities (10⁹—10¹⁰ohm-cm), and that the saturation magnetization Vs temperature curves had positive slopes at 10W temperature for x ≥ 1.50.