微波大功率稀土复合石榴石铁氧体的研究

Preparation of Gd- and Dy-Doped Composite Rare Earth Garnet with High Microwave Power

报道了用稀土元素Gd,Dy和金属元素Al,Mn等按适当比例部分置换Y,Fe制备钇钆镝复合石榴石铁氧体((YGdDy)IG)的研制方案和实验结果。实验结果表明,该种材料除具有优良的旋磁特性外,还兼备承受高平均功率和高峰值功率的性能。其主要特性参数为:4πMs依实用需要可在48～96mT内选择,且具有甚高的温度稳定度:在0～160℃范围内Ms的温度系数αM≤2.8×10-4℃-1;电阻率ρ高达1013Ω·m,介电损耗tanδe≤4×10-4;居里温度TC≥500K;共振线宽ΔH=3.4～6.4kA·m-1;门阈场Hcrit适用于MW级脉冲功率。该种铁氧体可用作甚高频及微波低频段、超大功率的环行器和变极化器等微波器件。

The theoretical and experimental study on preparation of the composite yttrium-iron granet,in which Y^(3+) and Fe^(3+) were replaced partly by rare earth elements Gd and Dy and metal elements Al, In, Mn with different and suitable mass ratio, were reported. The experimental results show that the rare-earth garnet ferrites not only possess excellent gyramagnetic features but also contain the property bearing high peak and average power of microwave. Their main electromagnetic parameters as follows: The saturation magnetization field 4πM_s is chosen at 48～96 mT according to application requirement, and the ferrites have very high stability to temperature,for example,its temperature coefficient α_M≤2.8×10^(-4) ℃^(-1) within (0～160 ℃), the Curie Temperature T_C≥500 K, the critical field H_(crit) is suited to peak power at MW level. The ferrite is used to manufacture microwave high power circulator and variable polarizer.