Fcc-to-bct phase transformation of aluminum under triaxial stresses: an ab initio constant pressure study
Department of Physics, University of Texas at El Paso, El Paso, TX, 79968, USA
Corresponding author: a email@example.com
Revised: 17 August 2009
Published online: 13 October 2009
We have carried out constant pressure ab initio simulations within a generalized gradient approximation to investigate the response of aluminum to triaxial stresses and found that aluminum undergoes a phase transformation from the face-centered cubic structure (fcc) to a body centered tetragonal (bct) structure having the space group of I4/mmm. The critical stress for the fcc-to-bct transformation increases as the ratio of the triaxial stress increases but such a phase transition never occurs under hydrostatic compression. The bct phase is elastically unstable.
PACS: 64.70.K- – Solid-solid transitions / 61.50.Ks – Crystallographic aspects of phase transformations; pressure effects / 62.50.-p – High-pressure effects in solids and liquids / 61.50.Ah – Theory of crystal structure, crystal symmetry; calculations and modeling
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2009