Effect of stoichiometry on the structural properties and the electronic structure of intermetallics: Anti-phase boundary energies in FeAl and NiAl

Journal Article · Wed Jan 01 00:00:00 EST 1992 · Journal of Materials Research; (United States)

DOI:https://doi.org/10.1557/JMR.1992.0068· OSTI ID:5048752

Hong, T ^[1]; Freeman, A J ^[2]

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1. Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208-3112 (United States)
2. Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208-3112 and Argonne National Laboratory, Argonne, Illinois 60349 (United States)

As a possible means of alleviating the severe brittleness in the B2 compounds FeAl and NiAl, the all-electron self-consistent total energy linear muffin-tin orbital (LMTO) method was employed to investigate the possibility of lowering the {l angle}111{r angle} anti-phase boundary (APB) energies by changing compositions in FeAl and NiAl. For APB's created in the regions with excess Fe (or Ni) atoms, APB energies for the model systems, Fe{sub 0.6}Al{sub 0.4} and Ni{sub 0.6}Al{sub 0.4}, were found to be one order of magnitude smaller than those for stoichiometric B2 FeAl and NiAl, respectively. Apparently, the activation of {l angle}111{r angle} slip became possible in these cases. On the other hand, the APB energies remained at about the same as those in stoichiometric FeAl and NiAl for APB's occurring in regions with equal numbers of Fe(Ni) and Al atoms, implying that the activation of {l angle}111{r angle} slip in these regions was not eased.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• OSTI ID: 5048752
• Journal Information: Journal of Materials Research; (United States), Vol. 7:1; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
STOICHIOMETRY
IRON ALLOYS
NICKEL ALLOYS
BINARY ALLOY SYSTEMS
ELECTRONIC STRUCTURE
ENERGY-LEVEL DENSITY
INTERMETALLIC COMPOUNDS
MUFFIN-TIN POTENTIAL
PHASE STUDIES
SELF-CONSISTENT FIELD
ALLOY SYSTEMS
ALLOYS
POTENTIALS
360104* - Metals & Alloys- Physical Properties