Abstract: The present disclosure discloses a preparation method of pressed Scandia-doped dispenser cathode using microwave sintering. Embodiments of the present disclosure include dissolving some nitrates and ammonium metatungstate with deionized water to prepare a homogeneous solution. Precursor powder with uniform size is obtained by spray drying, the precursor powder is decomposed, and two-step reduction may be proceeded to form doped tungsten powder with uniform element distribution. The cathode is prepared by one-time microwave sintering. One-time forming of cathode sintering is realized, and sintering shrinkage and sintering time are reduced significantly. The method has excellent repeatability, and the cathode has a homogeneous structure and excellent emission performance at 950° C.

Abstract: A carburized La2O3 and Lu2O3 co-doped Mo filament cathode is made from lanthanum oxide (La2O3) and lutetium oxide (Lu2O3) doped molybdenum (Mo) powders, the lanthanum oxide (La2O3) and lutetium oxide (Lu2O3) doped molybdenum (Mo) powders contain La2O3, Lu2O3 and Mo with the total concentration of La2O3 and Lu2O3 being 2.0-5.0 wt. % and the rest being Mo.

Abstract: A carburized La2O3 and Lu2O3 co-doped Mo filament cathode and its fabrication method, which belongs to the technical field of rare earth-refractory metal cathodes. The rare earth oxides are La2O3 and Lu2O3, and the total concentration of rare earth oxides ranges from 2.0-5.0 wt. %. The La2O3 and Lu2O3 co-doped molybdenum oxide powers are prepared by Sol-Gel method. La2O3 and Lu2O3 co-doped Mo powers are prepared by two calcining steps. Then pressing and sintering the mixed powders to obtain the molybdenum rods; operating mechanical and heat processes of the molybdenum rods to obtain molybdenum filament. Operating electrolytic cleaning, straightening, winding modeling and cutting treatments with Mo filament to obtain the un-carburized La2O3 and Lu2O3 co-doped Mo cathode. And then carburize the filament cathode at a high temperature for a short time to obtain a cathode with high carburization degree.

Abstract: The present disclosure discloses a preparation method of pressed Scandia-doped dispenser cathode using microwave sintering. Embodiments of the present disclosure include dissolving some nitrates and ammonium metatungstate with deionized water to prepare a homogeneous solution. Precursor powder with uniform size is obtained by spray drying, the precursor powder is decomposed, and two-step reduction may be proceeded to form doped tungsten powder with uniform element distribution. The cathode is prepared by one-time microwave sintering. One-time forming of cathode sintering is realized, and sintering shrinkage and sintering time are reduced significantly. The method has excellent repeatability, and the cathode has a homogeneous structure and excellent emission performance at 950° C.

Abstract: Impregnated rare earth metal-containing barium-aluminum-scandate cathodes with a rare earth oxide doped tungsten matrix and methods for the fabrication thereof are described. In one aspect, an impregnated rare earth metal-containing barium-aluminum-scandate cathode comprises: a rare earth oxide doped tungsten matrix, and an impregnated active substance. The active substance comprises scandium oxide (Sc2O3), a second rare earth oxide, and barium calcium aluminate, wherein the molar ratio of Ba:Ca:Al is about 4:1:1.

Abstract: Impregnated rare earth metal-containing barium-aluminum-scandate cathodes with a rare earth oxide doped tungsten matrix and methods for the fabrication thereof are described. In one aspect, an impregnated rare earth metal-containing barium-aluminum-scandate cathode comprises: a rare earth oxide doped tungsten matrix, and an impregnated active substance. The active substance comprises scandium oxide (Sc2O3), a second rare earth oxide, and barium calcium aluminate, wherein the molar ratio of Ba:Ca:Al is about 4:1:1.

Abstract: In a method of manufacturing a pressed scandate dispenser cathode, firstly, scandium nitrate, barium nitrate, calcium nitrate, aluminum nitrate and ammonium metatungstate (AMT) are dissolved in de-ionized water, respectively, and then mixed with a solution of a cross-link agent such as citric acid and H2O2. After water bathing, the mixed aqueous solution turns into gel, and the powders are obtained after the gel calcination. Secondly, the calcined powders are reduced by hydrogen. Finally, the reduced powders are pressed into shapes and then sintered in the furnace with the atmosphere of hydrogen or by Spark Plasma Sintering (SPS 3.202-MK-V) in vacuum.

Abstract: In a method of manufacturing a pressed scandate dispenser cathode, firstly, scandium nitrate, barium nitrate, calcium nitrate, aluminum nitrate and ammonium metatungstate (AMT) are dissolved in de-ionized water, respectively, and then mixed with a solution of a cross-link agent such as citric acid and H2O2. After water bathing, the mixed aqueous solution turns into gel, and the powders are obtained after the gel calcination. Secondly, the calcined powders are reduced by hydrogen. Finally, the reduced powders are pressed into shapes and then sintered in the furnace with the atmosphere of hydrogen or by Spark Plasma Sintering (SPS 3.202-MK-V) in vacuum.