氮化铝基微波衰减材料在高频行波管中的应用

应用于高频行波管中全匹配吸收模式的微波衰减材料需要具有好的高温稳定性、高的导热率以及高的衰减量.氮化铝基微波衰减材料由于成本低、性能好,已经取代BeO基复合材料而成功应用于实践.综述了AlNSiC、AlN-C、AlN-金属几种复相微波衰减材料的研究现状,比较分析了各体系的衰减特性.AlN-SiC复相陶瓷具有较好的宽频衰减特性,主要衰减机制为介电损耗,但存在难以烧结的问题;AlN-C复相陶瓷微波衰减量较低,限制了其在行波管中的应用;AlN-金属复相陶瓷衰减量大,但选频衰减特性相对比较明显.

AIN-based Microwave Lossy Materials Used for High Frequency Traveling Wave Tube

Lossy materials used in the high frequency traveling-wave tube require the high temperature stability,high thermal conductivity and high attenuation.Newly emerging lossy materials are based on AlN with various lossy additives,such as SiC,C and metal.They provide the microwave tube industry with a new alternative to the BeO matrix composites,offering the promise of lower cost with no compromise in performance.In this paper,several candidate lossy materials based on AlN matrix are introduced and a comparison of attenuation characteristics is provided.