First-principles atomic cluster study of boron interactions in Ni{sub 3}Al

Journal Article · Sat Mar 01 04:00:00 EST 1997 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.364266· OSTI ID:467199

Painter, G S; Fu, C L ^[1]; Averill, F W ^[2]

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1. Metals and Ceramics Division, Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, Tennessee 37831-6114 (United States)
2. Judson College, Elgin, Illinois 60123 (United States)

First-principles atomic cluster calculations have been carried out in the local density approximation to understand the segregation behavior and strengthening effects of boron in Ni{sub 3}Al. The binding energy of boron is calculated in lattice fragment clusters representing the perfect crystal, as well as various defect sites. The agreement between trends in energetics determined for small clusters and periodic supercells indicates the dominant role of boron`s interaction with nearest-neighbors of the host. The stereochemical factor underlying boron`s preferential bonding to nickel atoms in four-fold planar coordination (i.e., {ital sp}{sup 3} hybridization) suggests a mechanism for the boron-effect in Ni{sub 3}Al: increased cohesion provides a driving force for B segregation to open sites, such as at Ni-enriched grain boundary sites, and the strengthening is a result of strong localized Ni{endash}B covalent bond formation. {copyright} {ital 1997 American Institute of Physics.}

• Research Organization: Oak Ridge National Laboratory
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 467199
• Journal Information: Journal of Applied Physics, Journal Name: Journal of Applied Physics Journal Issue: 5 Vol. 81; ISSN JAPIAU; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
ATOMIC CLUSTERS
BINDING ENERGY
BORON ADDITIONS
BORON ALLOYS
BRITTLENESS
CHEMICAL BONDS
DOPED MATERIALS
GRAIN BOUNDARIES
GRAIN SIZE
MECHANICAL PROPERTIES
NICKEL BASE ALLOYS
SEGREGATION
density functional theory