Y2O3-Gd2O3-HfO2掺杂W基直热式阴极热发射及耐电子轰击特性研究

A study on the thermionic emission and anti-electron-bombing characteristics of the Y2O3-Gd2O3-HfO2 doping W base direct-heated cathode

摘要:

为了提高大功率磁控管阴极的耐电子轰击性能，首次采用Y2O3-Gd2O3-HfO2(Y-Gd-Hf-O)掺杂金属W粉制备大功率磁控管用直热式阴极。对不同质量百分比(wt%)Y-Gd-Hf-O掺杂W基直热式阴极的热发射及耐电子轰击特性进行了研究。实验结果显示，50 wt% Y-Gd-Hf-O掺杂W基直热式阴极具有较大的热发射能力，1500 ℃工作温度下即可提供1.0 A/cm2的拐点发射电流密度。10 wt% Y-Gd-Hf-O掺杂W基直热式阴极具有较好的耐电子轰击性能，经过14 W/cm2电子连续轰击200 h后，热发射电流密度仅下降0.1 A/cm2。最后，对Y-Gd-Hf-O掺杂W基直热式阴极热发射及耐电子轰击机理进行了有益的探讨。

Abstract:

In order to improve the anti-electron-bombing performance of the cathode applied in high-power magnetron tube. A method of Y2O3-Gd2O3-HfO2(Y-Gd-Hf-O) doping metallic W powders was used to prepare direct-heated cathode. The thermionic emission and anti-electron-bombing characteristics of different mass percent Y-Gd-Hf-O doping cathode were researched. Experimental results show that the 50 wt% Y-Gd-Hf-O doping cathode has large thermionic emission, which can provide 1.0 A/cm2 knee-point emitted current at 1500 ℃. The 10 wt% Y-Gd-Hf-O doping cathode has good anti-electron-bombing capability, whose thermionic emission current density has merely fell by 0.1 A/cm2 after 200 h continuous 14 W/cm2 electron bombing. At last, the thermionic emission and anti-electron-bombing mechanisms of the Y-Gd-Hf-O doping cathode were discussed reasonably.