Martensitic phase transitions HCP-DHCP and DHCP-FCC in Co 0.85 at% Fe

Author(s)
Markus Prem, Gerhard Krexner
Abstract

Co 0.85 at% Fe undergoes two phase transitions between close-packed structures: HCP-DHCP (at approximately 590 K upon heating) and DHCP-FCC (at approximately 690 K upon heating). Contrary to most martensitic transitions the phase transformations in this system do not occur discontinuously but a continuous change of the volume fractions of the phases takes place at constant temperature over a period of several hours. Measurements of the phonon dispersion show no anomalous softening of the tranverse branches related to the elastic constants c44 and c66 at either of the two transformations. An investigation of the elastic diffuse scattering along the [0 0.1] direction shows well-defined satellites at positions (n/4)*Q(00.2), n?Z, in the DHCP phase near the DHCP-FCC transition and at (n/12)*Q(00.2), n?Z, in the temperature region of DHCP-FCC coexistence. This behaviour found in the transition region reminds of earlier results found in pure cobalt where strain-induced satellites had been observed during the HCP-FCC transition.

Organisation(s)
Department of Mineralogy and Crystallography
Journal
Physica B: Condensed Matter
Volume
276
Pages
927-928
No. of pages
2
ISSN
0921-4526
DOI
https://doi.org/10.1016/S0921-4526(99)01596-3
Publication date
2000
Peer reviewed
Yes
Austrian Fields of Science 2012
1030 Physics, Astronomy
Portal url
https://ucrisportal.univie.ac.at/en/publications/0836218f-e82f-45c8-ae73-7dde81c9f2c3