On the site preferences of ternary additions to triple defect B2 intermetallic compounds

Conference · Sun Dec 31 04:00:00 EST 1995

OSTI ID:216302

Pike, L M; Chen, S L; Chang, Y A ^[1]

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1. Univ. of Wisconsin, Madison, WI (United States); and others

Knowledge of the site preference of ternary solute additions is essential to developing an understanding of how these solutes affect the properties of B2 intermetallic compounds. A quasichemical model will be presented which is able to predict the site preferences of dilute solute additions to triple defect B2 compounds. The only parameters required are enthalpies of formation at the stoichiometric composition. General equations are developed which can be used to determine site occupations and defect concentrations for dilute as well as non-dilute solute additions. These equations use atom pair bond enthalpies as the parameters. It is found that the site preferences of dilute additions are not always in agreement with predictions based on the solubility lobes in ternary Gibbs isotherms, Predictions for dilute additions to NiAl and FeAl are compared to experimental results found in the literature. Satisfactory correlation is found between the model and the experimental results. In addition, the predictions from the model on vacancy concentrations in Fe doped NiAl are compared to recent experimental results by the authors.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC05-96OR22464
• OSTI ID: 216302
• Report Number(s): CONF-950008--1; ON: DE96009723
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
CRYSTAL DEFECTS
DOPED MATERIALS
ENTHALPY
INTERMETALLIC COMPOUNDS
IRON ALLOYS
ISOTHERMS
MATHEMATICAL MODELS
NICKEL ALLOYS
SOLUBILITY
TERNARY ALLOY SYSTEMS
VACANCIES