High-pressure ultrasonic study of vibrational anharmonicity in bcc Cu-Al-Be alloys
To quantify the vibrational anharmonicity of the long-wavelength acoustic modes of bcc Cu74.1Al23.1Be2.8 near its martensitic transition temperature Ms (261 K), the hydrostatic pressure derivatives (¿CIJ/¿P)P=0 of the elastic stiffness moduli have been measured. The Grüneisen parameters at 268 K (ju...
| Autores: | , , , |
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| Tipo de recurso: | artículo |
| Estado: | Versión publicada |
| Fecha de publicación: | 1992 |
| País: | España |
| Institución: | Universidad de Barcelona |
| Repositorio: | Dipòsit Digital de la UB |
| OAI Identifier: | oai:diposit.ub.edu:2445/9905 |
| Acceso en línea: | https://hdl.handle.net/2445/9905 |
| Access Level: | acceso abierto |
| Palabra clave: | Transformacions martensítiques Aliatges Martensitic transformations Alloys |
| Sumario: | To quantify the vibrational anharmonicity of the long-wavelength acoustic modes of bcc Cu74.1Al23.1Be2.8 near its martensitic transition temperature Ms (261 K), the hydrostatic pressure derivatives (¿CIJ/¿P)P=0 of the elastic stiffness moduli have been measured. The Grüneisen parameters at 268 K (just above Ms), especially of longitudinal modes, which become smaller than those of the shear modes, are quite different from those at 295 K: the anharmonicity changes markedly in the vicinity of the transition. Similar trends are noted for Cu66.5Al12.7Zn20.8. Experimental data near Ms are used to estimate cubic invariants in the strain order parameters in a Landau formalism. |
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