Evaporation and lifetime of the Ammonium Perrhenate Impregnated W Matrix Ba-W Cathode

In this paper we mainly describes the research progress in a kind of ammonium perrhenate impregnated W matrix Ba-W cathode, which includes the evaporation rate measuring and the lifetime testing of the cathode. The evaporation rate measuring results shows that the evaporation rate of the cathode is 8.66 x 10(-10)g.cm(-2) s(-1) at 1000 degrees Cbr measured by a quartz crystal oscillating method. The lifetime testing results show that the emission current, after 22392h lifetime at a temperature of 1000 degrees Cbr, has still increased more than 6% of the initial 3.0 A/cm(2) DC current density.