STUDY ON THE ROLE OF CALCIUM OXIDE AND SCANDIUM OXIDE IN THE IMPREGNATED BARIUM ALUMINATE CATHODE
铝酸盐钡钨阴极中掺氧化钙和氧化钪的作用机理

The role of calcium oxide in the barium aluminate and that of calcium oxide and scandium oxide both doped in the impregnated barium aluminate cathode are analytically studied. The results indicate that there are common consitituents, i.e. 2BaO ·CaO · Al2O3 and utilizable barium oxide in the emission substances of various impregnated barium-calcium-aluminate cathodes. The calcium oxide in the barium aluminates participates in constituting 2BaO·CaO·Al2O3. It makes the utilizable barium oxide stable. The scandium oxide doped in the barium-calcium-aluminate 5BaO·3CaO·2Al2O3·0.6Sc2O3 compound is supposed to be a carrier for aarium oxide or barium atom which is the electron source, and it plays the role in controlling and roplonishing the electron source. The proposed mechanism has been proved by some experimental data.