Effect of Impregnation on the Performance of Sc2O3-doped Tungsten Matrix Cathodes
High emission and long lifetime scandate cathode is one of the key research directions of high current density cath-odes.In order to improve the working stability and increase the proportion of scandium element on the surface of cathodes,a com-bination of scandate cathodes was obtained based on the high uniform Sc2O3-doped tungsten matrix and high emission scandate.In this paper,the impregnation effect on the emission performance and lifetime of Sc2O3-doped tungsten matrix cathodes are investiga-ted.The results show that the active substance is fully filled in the matrix when the impregnation amount is larger than 6.4 wt%and the obtained scandate cathode can work stably in the low vacuum environment with high current density of 20 A/cm2 for more than 400 Hrs.