| 摘要 |
PURPOSE:To lower a dispersion of electron radiant material, by such means that, a mixed power between electron radiant material and heat resistant material is processed a firing and granulation, after being coated this granular surface by the heat resistant material, pressure formed, with a sintering processed at a temperature higher than the temperature of preceding process of firing. CONSTITUTION:A mixing is made between the powder of electron radiant material like oxide, carbonate, etc. of Ba, Ca, Sr and the powder of heat resistant metal, heat resistant oxide like W, Mo, ZrO2, Al2O3, ThO3, Y2O3, etc., with a firing processed at a temperature or 1250-1350 deg.C in the ambience of neturality or reduction. Subseqently, after being finely crushed in a suitable organic binder, a construction is made into a granule of 10-500mu, further with this granule coated by a heat resistant metal, heat resistant oxide of mean granular diameter less than 8mu, and this coated compound particle is pressure formed into a prescrived shape 1, simultaneously with an electrode bar 2 inserted. And then a sintering is processed at about 1350-1500 deg.C in a vacuum oven or reducing atmospheric furnace. |
