Accession Number : AD0660439

Title :   WORK FUNCTIONS OF W-HF, TA-HF, NB-HF, RE-HF, RE-ZR AND W-RE ALLOYS,

Corporate Author : FOREIGN TECHNOLOGY DIV WRIGHT-PATTERSON AFB OHIO

Personal Author(s) : Dyubua,B. Ch. ; Kultashev,O. K.

Report Date : 03 MAY 1967

Pagination or Media Count : 17

Abstract : The paper presents data on the work function of refractory metals in which various amounts of hafnium and zirconium have been dissolved. The work function was determined from the Richardson-Dushman equation for A = 120.4 A/sq cm deg. to the 2nd power. The thermionic emission measurements were carried out in a vacuum of 10 to the minus 8th power - 10 to the minus 9th power mm Hg. The phase composition of the alloys was determined by microstructural analysis. The work function of pure Re, Ta, Nb, and Zr was shown to remain constant with changing temperature. The addition of hafnium and zirconium was found to decrease the work function of the refractory metals. The cause of this effect is thought to be the adsorption of hafnium and zirconium atoms on the surface of the solid solution. In the region of the sigma phase of the W-Re alloy an increase in work function up to 5.0 eV was observed. This is attributed to a possible adsorption of rhenium. (Author)

Descriptors :   (*TUNGSTEN ALLOYS, WORK FUNCTIONS), (*TANTALUM ALLOYS, WORK FUNCTIONS), (*NIOBIUM ALLOYS, WORK FUNCTIONS), (*RHENIUM ALLOYS, WORK FUNCTIONS), (*REFRACTORY METALS, WORK FUNCTIONS), HAFNIUM ALLOYS, ZIRCONIUM ALLOYS, REFRACTORY METAL ALLOYS, THERMIONIC EMISSION, PHASE DIAGRAMS

Subject Categories : Metallurgy and Metallography

Distribution Statement : APPROVED FOR PUBLIC RELEASE