前向波放大管用冷阴极Pd-Ba合金的研究

Pd-Ba Cold Cathode Materials Used in Crossed-Field Amplifier

冷阴极作为微波放大管的核心组件, 它对冷阴极材料有着严格的技术要求. 经过中频炉熔炼, 压力加工以及热处理, 制备了厚度尺寸范围0.10～0.20 mm的Pd-Ba合金箔材. 经均匀化热处理, 有效地改变了Pd-Ba合金中第二相的形态而趋于粒状化, 同时增强了第二相与基体金属的结合能力, 使阴极片在正常装管打磨处理过程中第二相不发生脱落, 保证了合金表面的Ba含量. 在一次电子轰击功率为100 W·cm-2, 连续轰击2500 h后, 最大二次电子发射系数稳定在δmax2.55～2.6, 满足特定型号微波放大管对冷阴极最大二次电子发射系数的严格要求.

Cold cathode is applied as the important component in the crossed-field amplifier (CFA) and has critical requirements for cold cathode materials. Middle-frequency melting, deformed process and final heat-treatment were used to prepare Pd-Ba alloy foil with thickness in range of 0.1～0.2 mm. After uniform heat treatment, the second-phase pattern in Pd-Ba alloy turns to spheroidic, at the same time, the binding ability between the second-phase and the matrix metal is reinforced. That ensures the second-phase a...