Certain Refractory Compounds as Thermionic Emitters

Abstract

Several refractories of the nitride, boride, and carbide families are investigated as sources of thermionic electrons. An activation pattern qualitatively common to several of the compounds is observed. Emission data for the final state of activation are presented. Data concurrently obtained for thoria are also given for comparison. True temperature used in the Richardson equation is obtained by correction from brightness temperature. Temperature correction curves have been obtained. These curves can be satisfactorily represented in the region of thermionic emission by one value of spectralemissivity, which values are listed for the materials studied.