List of publications
Physical Review B, 91, 174105, (2015) [doi: 10.1103/PhysRevB.91.174105]
Mechanism of the α−ε phase transformation in iron
A. Dewaele, C. Denoual, S. Anzellini, F. Occelli, M. Mezouar, P. Cordier, S. Merkel, M. Véron, and E. Rausch
The α-Fe↔ε-Fe pressure-induced transformation under pure hydrostatic static compression has been characterized with in situ x-ray diffraction using α-Fe single crystals as starting samples. The forward transition starts at 14.9 GPa, and the reverse at 12 GPa, with a width of α−ε coexistence domain of the order of 2 GPa. The elastic stress in the sample increases in this domain, and partially relaxes after completion of the transformation. Orientation relations between parent α-Fe and child ε-Fe have been determined, which definitely validates the Burgers path for the direct transition. On the reverse transition, an unexpected variant selection is observed. X-ray diffraction data, complemented with ex situ microstructural observations, suggest that this selection is caused by defects and stresses accumulated during the direct transition.
Full text of this article is available online.