| 摘要 |
FIELD: electronic engineering. ^ SUBSTANCE: proposed method includes step-by-step annealing of source powder at temperature ranging between 1650 and 1750°C including temperature rise by 25-50°C, cake milling, powder quality control upon every annealing step by producing sample pellet compressed at constant pressure Psp, and evaluation of pressure P of air flowing through sample pellet upon second annealing step until pressure P is attained after at least two annealing steps corresponding to mean powder particle diameter over 4.5 mum, for instance, for Psp = 2.8 t/cm2 at P <= 0.45 kg/cm2 which are values of its open steam channel in terms of air pressure; this is followed by compression of pellets from powder obtained, their sintering in acid-free medium, and impregnation of sintered pellets in emission-active material; powder particle mean diameter Dp is calculated and should be minimum 4.5 mum but not over 7.0 mum; density range of sintered pellets rhosn min - rhosn max is calculated basing on pressure of air flowing through sample pellet using equations rhosn min = 12.35 - 0.03 Dp + 0.05 Dp 2, rhosn max = rhosn min+ 20, where rhosn min (g/cm3) meets condition of minimal open steam channel from its optimal range for given production and rhosn min, condition of maximal open steam channel, and compressing pressure is chosen from values of rhosn min and rhosn max using standard dependence of sintered pellet density as function of specific compressing pressure rhosn = f(Psp). ^ EFFECT: enhanced life of cathodes, reduced evaporation from them. ^ 1 cl, 3 dwg, 3 tbl |
