High pressure arc discharge lamp having barium hafnate impregnated electrodes

摘要

An electron emitting, barium hafnate material for arc discharge lamp electrodes is manufactured by the method comprising the steps of: forming a mixture of barium carbonate and hafnium oxide in a 48 to 52 mole ratio; adding the mixture to a suitable carrier to form a slurry; ball milling the slurry for about 2 hours to form a powder mix; drying the powder mix; firing the dried powder mix in air at about 1500 DEG C. for about 22 hours to produce a product; and vibration milling the product in methanol with zirconia media to produce the barium hafnate. The latter material is then preferably vacuum impregnated into a tungsten electrode and hydrogen fired to produce a single phase barium oxide/hafnium oxide compound.