Interfacial energies in two-phase TiAl-Ti{sub 3}Al alloy
- Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.
The intrinsic values of interfacial energies based on first-principles calculations, including atomic relaxation, were obtained for the three types of {gamma}/{gamma} interfaces and the {alpha}{sub 2}/{gamma} lamellar boundary in two-phase TiAl alloy. The pseudo-twin boundary energy is highest, {Gamma}{sub p} = 270 mJ/m{sup 2}, and the true-twin boundary energy is lowest, {Gamma}{sub {tau}} = 60 mJ/m{sup 2}. Planar fault energies at pseudo-twin and 120{degree}-rotational interfaces are markedly different from those in the bulk of the {gamma}-phase, i.e., approximately, E{sub APS} and E{sub CSF} decreases by more than 0% and E{sub SISF} increases by threefold. Enhanced mobility of ordinary dislocations along the {gamma}/{gamma} and {alpha}{sub 2}/{gamma} interfaces (except true twin boundaries) is predicted based on the reduced E{sub CSF} values at the interfaces.
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC05-96OR22464
- OSTI ID:
- 554047
- Journal Information:
- Scripta Materialia, Journal Name: Scripta Materialia Journal Issue: 10 Vol. 37; ISSN 1359-6462; ISSN SCMAF7
- Country of Publication:
- United States
- Language:
- English
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