Mohan, Murali and Singh, AK (1994) Kinetics of the pressure-induced hcp -+ fcc transformation in thallium. In: Proceedings of the National Conference on High Pressure Science and Technology, 10-11 Oct 1994, Bangalore, India.
Full text available as:| PDF Download (539Kb) |
Abstract
The progress of the hcp + fcc transformation in T1 has been monitored as a function of time, t, under isobaric-isothermal conditions in the pressure range 3.4 - 4.1 GPa at 300K. The decrease in the electrical resistance of the specimen, associated with the transformation, has been used to obtain the fraction, C, of the fcc phase as a function o f t at desired pressures in the above range. The results indicate that (i) the time for C = 0.9 decreases from -105s at 3.4 GPa to wlOs at 4.1 GPa (ii) the activation free energy for the total process decreases from N 14 kcal mol-' at 3.5 GPa to -10.5 kcal mol-' at 413; GPa (iii) the activation volume in the 3.4 - 4.1 GPa range is -30.5 cm3 mol-'.Contrary to our earlier results on the a -+ w transformation in Ti and the fcc -+ bcc transformation in Yb, the hcp -+ fcc transformation in TI does not exhibit an incubation period, and the C-t data do not satisfy the standard form of the Avrami equation.
| Item Type: | Conference or Workshop Item (Paper) |
|---|---|
| Uncontrolled Keywords: | Kinetics;Transformation;Thallium |
| Subjects: | PHYSICS > Physics(General) |
| Division/Department: | Materials Science Division, Materials Science Division |
| Depositing User: | M/S ICAST NAL |
| Date Deposited: | 20 Aug 2008 |
| Last Modified: | 17 Jun 2010 13:54 |
| URI: | http://nal-ir.nal.res.in/id/eprint/4902 |
Actions (login required)
| View Item |

