Study on a novel Y2O3-Gd2O3-HfO2 impregnated W base direct-heated cathode

In order to enhance the emission current, reduce the operating temperature and prolong the lifetime of the pure W filament cathode for application in high-power (i.e., more than 10KW) continuous wave magnetron tube, a novel Y
₂
O
₃
-Gd
₂
O
₃
-HfO
₂
impregnated W base direct-heated cathode (Y-Gd-Hf-O impregnated cathode) has been developed. At 1700°br, the dc emission density of the Y-Gd-Hf-O impregnated cathode can reach to 10.5A/cm
²
. After 3600 h operation of the cathode under 1600°br, the dc emission current density of it is still stable at the initial value of 1.5A/cm
²
.