The electronic Lorenz number in some transition metals at high temperatures

• Published in: Journal of physics. Condensed matter Vol. 2; no. 3; pp. 631 - 639
• Main Authors: Chari, M S R, Chari, M V N
• Format: Journal Article
• Language: English
• Published: Bristol IOP Publishing 22.01.1990; Institute of Physics
• Subjects: Analysing. Testing. Standards; Applied sciences; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Cross-disciplinary physics: materials science; rheology; Electrical and thermal conduction in crystalline metals and alloys; Electronic conduction in metals and alloys; Electronic transport in condensed matter; Exact sciences and technology; Materials science; Measurement of properties and materials state; Metals, semimetals and alloys; Metals. Metallurgy; Nondestructive testing; Physics; Specific materials; Phenomenological model; Lorenz number; Electrical conductivity; Theoretical study; Thermal conductivity; Transition metal; High temperature; Lattice thermal conductivity
• ISSN: 0953-8984; 1361-648X
• DOI: 10.1088/0953-8984/2/3/011

The usual method of plotting the high-temperature electrical resistivity rho and thermal conductivity lambda data on transition metals in the form of lambda T against T exp 2 / sigma plots gives a negative lattice thermal conductivity lambda sub g , when applied to vanadium, Rh, Pd and cobalt. It is shown that lambda T for these metals, plotted against T exp 2 , gives positive lambda sub g and electronic Lorenz numbers L* sub e , which depend on T in a particular manner, namely in proportion to sigma . These values of L* sub e broadly conform to Kolomoets' theory. When applied to the data on Ti, Zr and hafnium, the values obtained for from the lambda T against T exp 2 / sigma plots. In the case of polycrystalline and wire-form Nb, the values of L* sub e conform to Kolomoets' theory while the L* sub e obtained from the lambda T against T exp 2 / sigma plots do not. Graphs. 26 ref.--AA