Analytic embedded atom method model for bcc metals

Journal Article · Fri Sep 01 04:00:00 EDT 1989 · Journal of Materials Research; (USA)

DOI:https://doi.org/10.1557/JMR.1989.1195· OSTI ID:5487860

Johnson, R A; Oh, D J ^[1]

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1. Materials Science Department, University of Virginia, Charlottesville, Virginia 22901 (US)

The requirements for fitting bcc metals within the EAM format are discussed and, for comparative purposes, the EAM format is cast in a normalized form. A general embedding function is defined and an analytic first- and second-neighbor model is presented. The parameters in the model are determined from the cohesive energy, the equilibrium lattice constant, the three elastic constants, and the unrelaxed vacancy formation energy. Increasing the elastic constants, increasing the elastic anisotropy ratio, and decreasing the unrelaxed vacancy formation energy favor stability of a close-packed lattice over bcc. A stable bcc lattice relative to close packing is found for nine bcc metals, but this scheme cannot generate a model for Cr because the elastic constants of Cr require a negative curvature of the embedding function.

• OSTI ID: 5487860
• Journal Information: Journal of Materials Research; (USA), Journal Name: Journal of Materials Research; (USA) Vol. 4:5; ISSN JMREE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
BCC LATTICES
COMPUTERS
CORRELATIONS
CRYSTAL DEFECTS
CRYSTAL LATTICES
CRYSTAL MODELS
CRYSTAL STRUCTURE
CUBIC LATTICES
ELASTICITY
ELEMENTS
ENERGY
ENERGY SYSTEMS
EQUILIBRIUM
FCC LATTICES
FUNCTIONS
LATTICE PARAMETERS
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
METALS
POINT DEFECTS
TENSILE PROPERTIES
TOTAL ENERGY SYSTEMS
VACANCIES