Abstract: A high emission of electrons, as a result of negative electron affinity, has been achieved from an insulating nitride coated with a film of an electropositive work function reducing material.

Abstract: Mechanical retension of a lead having a core material with a ductile metal plating of lower melting temperature is provided within a receiving opening of a fired ceramic body by heating the lead within the opening of the ceramic body to a temperature between the melting temperature of the plating on the lead and the melting temperature of the core material of the lead. A charge of molten plating material is formed and cast thereby, substantially by capillary action, within an interstitial opening at the lead-ceramic interface substantially conterminous to surfaces of interior surface irregularities within the opening. Upon cooling, an integral lead-ceramic body is formed wherein the lead is anchored within its receiving opening substantially by the casting of the plating material within the surface irregularities.