Accession Number : AD0701394

Title :   THERMODYNAMIC PROPERTIES OF TERNARY REFRACTORY CARBIDES. III. ZIRCONIUM-HAFNIUM-CARBON.

Descriptive Note : Technical rept. 1 Jul 67-30 Jun 69,

Corporate Author : CINCINNATI UNIV OHIO

Personal Author(s) : Hoch,M. ; Yamauchi,S.

Report Date : DEC 1969

Pagination or Media Count : 29

Abstract : The thermodynamic properties of ternary zirconium-hafnium carbide, Zr(x)Hf(1-x)C(y), having the sodium-chloride type structure were studied, using the time-of-flight mass spectrometer. The ratios of the activities of the components were measured as a function of composition at 2440K. From the variation of the ratio of activities with composition, the pairwise interaction energies were obtained. The metal-metal interaction energy (E(12)-(E(11)+E(22))/2) = 1.9 plus or minus 0.3 kcal/mole, similar to that in the body-centered cubic zirconium-hafnium metallic system. The difference between the zirconium-carbon and hafnium-carbon interaction energy E(13)-E(23) is a function of composition and can be expressed as: E(13)-E(23) = (9.8 plus or minus 0.05)-(7.5 plus or minus 0.2)x in kcal/mole. (Author)

Descriptors :   (*CARBIDES, *CRYSTAL LATTICES), (*REFRACTORY MATERIALS, CARBIDES), PHASE STUDIES, ZIRCONIUM COMPOUNDS, HAFNIUM COMPOUNDS, SOLID SOLUTIONS, CHEMICAL BONDS, THERMODYNAMICS, MASS SPECTROSCOPY

Subject Categories : Ceramics, Refractories and Glass
      Atomic and Molecular Physics and Spectroscopy

Distribution Statement : APPROVED FOR PUBLIC RELEASE