Interatomic potentials for atomistic studies of defects in binary alloys

Journal Article · Mon Nov 01 04:00:00 EST 1982 · Acta Metall.; (United States)

DOI:https://doi.org/10.1016/0001-6160(82)90104-3· OSTI ID:5963013

Maeda, K; Sutton, A P; Vitek, V

A description of interatomic forces in pure metals and disordered, substitutional binary alloy systems is developed on an empirical basis. The description is formulated for use in atomistic studies of lattice defects. In both pure metals and alloys the total internal energy is expressed as the sum of two terms: a pair potential term and a term that depends only on the average density of the material. It is assumed that in pure metals all of the cohesive energy is provided by the second term. The empirical parameters employed in the construction of potentials for pure metals are the cohesive energy and elastic constants. For alloys the different atomic sizes and electronegativities of the alloying elements are taken into account, and the potentials are self-consistently adjusted to the enthalpy of mixing fo corresponding alloy concentrations. In addition all potentials are required to satisfy the equilibrium conditions governing mechanical stability of the corresponding crystal structures. Reasonable agreement is obtained between calculated dependences of elastic constants on alloy concentration and available experimental data. Several derived potentials for pure metals and alloys are presented, in particular those employed in a subsequent atomistic study of grain boundary segregation. The scheme can be used to construct approximate descriptions of atomic interactions in specific binary systems, or for th construction of model systems in which the required empirical data are taken as variables.

• Research Organization: Department of Materials Science and Engineering, University of Pennsylvania, Philadelphia, PA 19104
• DOE Contract Number: AC02-79ER10429
• OSTI ID: 5963013
• Journal Information: Acta Metall.; (United States), Journal Name: Acta Metall.; (United States) Vol. 30:11; ISSN AMETA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOYS
ATOMIC MODELS
ATOMIC RADII
BINARY MIXTURES
BINDING ENERGY
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DISPERSIONS
ELASTICITY
ELECTRONEGATIVITY
ELEMENTS
ENERGY
ENERGY DENSITY
ENTHALPY
GRAIN BOUNDARIES
INTERATOMIC FORCES
MATHEMATICAL MODELS
MECHANICAL PROPERTIES
METALS
MICROSTRUCTURE
MIXING
MIXTURES
PAIRING ENERGY
PHYSICAL PROPERTIES
POTENTIALS
QUANTITY RATIO
SEGREGATION
TENSILE PROPERTIES
THERMODYNAMIC PROPERTIES