| Numéro |
J. Phys. Colloques
Volume 43, Numéro C4, Décembre 1982
ICOMAT-82International Conference on Martensitic Transformations |
|
|---|---|---|
| Page(s) | C4-133 - C4-138 | |
| DOI | https://doi.org/10.1051/jphyscol:1982413 | |
International Conference on Martensitic Transformations
J. Phys. Colloques 43 (1982) C4-133-C4-138
DOI: 10.1051/jphyscol:1982413
BETA-PHASE INSTABILITY AND MARTENSITIC TRANSFORMATION IN Ti-22 a/o Nb ALLOY
P. Hochstuhl1 et B. Obst21 Universität Karlsruhe, Institut für Experimentelle Kernphysik, F.R.G.
2 Kernforschungszentrum Karlsruhe, Institut für Technische Physik, F.R.G.
Abstract
The variation of the electrical resistivity with temperature (4 to 300 K) and strain has been measured in solid solution Ti-22 a/o Nb. The experiments have been conducted on a tensile machine equipped with a temperature-variable flow cryostat. Depending on the sample history, the value of the temperature-coefficient of resistivity appears to be abnormal. In the as-quenched condition, the alloy shows a negative dρ/dT in a certain range of temperatures. The resistivity-temperature relation is found to be reversible (no hysteresis) ; variations with ageing time have been observed. The resistance anomaly appears to be closely related to the incipient instability of the ß phase as the system tends towards thermodynamic equilibrium. Polymorphic transformations will produce a kinetic barrier for further ß instability.