Elastic properties of the Ta–V system: bcc Ta0.33V0.67 and C15 TaV2 |
| |
Authors: | DS Agosta AV Skripov |
| |
Institution: | 1. Department of Physics , Colorado State University , Fort Collins, CO 80523, USA;2. Institute of Metal Physics , Urals Branch of the Russian Academy of Sciences , Ekaterinburg 620041, Russia |
| |
Abstract: | Resonant ultrasound spectroscopy was used to measure the elastic constants of bcc Ta0.33V0.67 over the temperature range 3.5–300?K; the results were compared to earlier measurements on C15 TaV2. The temperature dependence of the polycrystalline shear modulus is completely different in the two phases; that of the bcc phase decreases with temperature whereas that of the C15 phases increases in an anomalous fashion. This difference is consistent with a model involving doubly-degenerate levels at the X point of the Brillouin zone in the C15 phase with the Fermi level lying near the doubly degenerate level. This model accounted for the unusual behaviour of the C15 phase. Debye temperatures were determined from the ultrasonic measurements: 295?K for the C15 phase and 315?K for the bcc phase. |
| |
Keywords: | |
|
|