Diffusion along (001) tilt boundaries in the Au/Ag system--II. Atomistic modeling and interpretation

Journal Article · Thu Dec 31 23:00:00 EST 1992 · Acta Metallurgica et Materialia; (United States)

DOI:https://doi.org/10.1016/0956-7151(93)90346-T· OSTI ID:6326928

Ma, Qing ^[1]; Liu, C L; Adams, J B ^[2]; Balluffi, R W ^[3]

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1. Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Physics
2. Univ. of Illinois, Urbana, IL (United States). Dept. of Materials Science and Engineering
3. Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials, Science and Engineering

The low temperature boundary diffusion data obtained in Part I were modeled using elementary vacancy, interstitially and interstitial defect mechanisms. First, boundary structures were calculated using the embedded atom method. Point defect formation energies at different boundary sites and migration energies between them were then calculated, and values of [delta][sub b]D[sub b] were determined using recently developed expressions for this quantity. The results indicate that the diffusion is dominated by a small number of jumps having relatively small activation energies and large partial correlation factors. Also, interstitial-related mechanisms make important (and perhaps dominant) contributions to the diffusion. Both the data and modeling indicate Arrhenius pre-exponential factors considerably smaller than those reported at high temperatures. It is suggested that additional jumps (possessing higher effective activation energies) exist, and that their contributions become dominant at high temperatures. Finally, the observed [delta][sub b]D[sub b] vs misorientation behavior is found to be qualitatively consistent with the structural unit model.

• DOE Contract Number: FG02-87ER45310; FG02-91ER45439
• OSTI ID: 6326928
• Journal Information: Acta Metallurgica et Materialia; (United States), Journal Name: Acta Metallurgica et Materialia; (United States) Vol. 41:1; ISSN 0956-7151; ISSN AMATEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360104* -- Metals & Alloys-- Physical Properties
ACTIVATION ENERGY
ARRHENIUS EQUATION
ATOM TRANSPORT
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DATA
DIFFUSION
ELEMENTS
ENERGY
EQUATIONS
GOLD
GRAIN BOUNDARIES
INFORMATION
INTERSTITIALS
MATHEMATICAL MODELS
METALS
MICROSTRUCTURE
NEUTRAL-PARTICLE TRANSPORT
NUMERICAL DATA
POINT DEFECTS
RADIATION TRANSPORT
SILVER
TEMPERATURE DEPENDENCE
THEORETICAL DATA
TRANSITION ELEMENTS
VACANCIES