Thermal expansion of Cr, Mo and W at low temperatures
โ Scribed by G.K. White; T.F. Smith; R.H. Carr
- Publisher
- Elsevier Science
- Year
- 1978
- Tongue
- English
- Weight
- 272 KB
- Volume
- 18
- Category
- Article
- ISSN
- 0011-2275
No coin nor oath required. For personal study only.
โฆ Synopsis
Linear expansion coefficients have been measured for Cr, Mo and W from 2-30 K, 55-90 K, and near room temperature. At low temperatures, the lattice contributions for Mo and W, although small, are determined to better than 10% giving respective limiting values of the lattice GriJneisen parameter, 3'o, of 1.3and 1.35compared with 3,(283 K) = 1.61; their electronic components are very different, giving 3,e = d In N(EF)/d In V = I. 1 (Mo) and 0.3 (W). For Cr, the "electronic" term is large and negative at low temperatures, giving 3,ern = -9; anomalies occur in ~ (7") at 124 and 311 K.
๐ SIMILAR VOLUMES
VANADIUM, niobium, and tantalum are three transition elements with relatively large electronic specific heats; they are also supercondfictors. Interest in their low temperature expansion properties, therefore, lies in the fact that not only should useful information be obtained about their lattice d
The linear thermal expansion coefficient, a, has been measured from 2 to 32 K and from 55 to 90 K for a machineable glass-ceramic, an "ultra-low expansion" titanium silicate glass (Coming ULE), and ceramic glasses (Cer-Vit and Zerodur), and for glassy carbon, a is negative for the ultra-low expansio