Theory of the phase diagram of iron and thallium: The Burgers and Bain deformation mechanisms revised

Journal Article · Tue Oct 01 04:00:00 EDT 1991 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.44.7248· OSTI ID:5173379

Dmitriev, V P; Gufan, Y M ^[1]; Toledano, P ^[2]

---

1. Institute of Physics, Rostov State University, 344104 Rostov on Don (U.S.S.R.)
2. Laboratory of Phase Transitions, University of Amiens, 80000 Amiens (France)

A theoretical model is proposed for the pressure-temperature phase diagram of iron and thallium. A unified phenomenological and atomistic description is given for the Burgers and Bain deformation mechanisms. The bcc-hcp and bcc-fcc transformations are associated, respectively, with six- and two-dimensional order parameters, which are expressed as periodic functions of the atomic displacements. The fcc-hcp transformation is interpreted as a displacive transition between two low-symmetry phases. A thermodynamic potential describing the three preceding transformations is constructed, and the corresponding theoretical phase diagram, including the triple point, is worked out. It is compared to the experimental phase diagrams of iron and thallium.

• OSTI ID: 5173379
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 44:14; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
BCC LATTICES
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CUBIC LATTICES
DIAGRAMS
ELEMENTS
FCC LATTICES
HCP LATTICES
HEXAGONAL LATTICES
IRON
METALS
ORDER PARAMETERS
PHASE DIAGRAMS
PRESSURE DEPENDENCE
TEMPERATURE DEPENDENCE
THALLIUM
TRANSITION ELEMENTS