Patent ID: 7722804

Claim:
A method of manufacturing pressed scandate doped cathodes comprising the steps of: providing Sc(NO 3 ) 3 .xH 2 O, Ba(NO 3 ) 2 , Ca(NO 3 ) 2 .xH 2 O, Al(NO 3 ) 3 .xH 2 O and (NH 4 ) 6 H 6 W 12 O 40 .xH 2 O (AMT) as raw materials, wherein the raw materials correspond to 3-5 wt % of Sc 2 O 3 , total 5 wt %-15 wt % of CaO, Al 2 O 3 and BaO, and balanced with the (NH 4 ) 6 H 6 W 12 O 40 .xH 2 O (AMT); dissolving the raw materials in de-ionized water, respectively, to obtain a raw material solution; mixing the raw material solution with a cross-linking agent solution to form a sol in a water bath at a temperature between 80° C. and 100° C.; drying the sol in air at a temperature between 80° C. and 100° C. to form a gel; calcining the gel in the atmosphere of air/oxygen at a temperature between 500° C. and 550° C. for 2-5 hours to obtain complex oxide powders; reducing the complex oxide powders at a temperature of 500° C. in the atmosphere of hydrogen, followed by reduction at a temperature between 850° C. and 1000° C. in the atmosphere of hydrogen, so as to obtain composite oxide doped tungsten powders; pressing the composite oxide doped tungsten powders at a pressure between 1.5 t/cm 2 to 2.5 t/cm 2 and sintering in the atmosphere of hydrogen at a temperature between 1450° C. and 1650° C. for 1 to 10 minutes or sintering in vacuum at a temperature between 1100° C. and 1450° C. for 1 to 10 minutes by Spark Plasma Sintering (SPS apparatus type 3.202-MK-V), to form the pressed scandate doped cathodes.