Atomic ordering characteristics of Ni{sub 3}Al intermetallics with substitutional ternary additions
- Middle East Technical Univ., Ankara (Turkey). Dept. of Metallurgical and Materials Engineering
The effects of substitutional ternary additions of Me = Zn, Ti, Si, Cr, Mn, Mo, W, Nb, Ta, V, Hf, or Zr on the energetical and structural characteristics of atomic short-range ordering (SRO) of Ni{sub 3}(Al{sub 1{minus}x}Me{sub x}) intermetallics with Ll{sub 2} type ordered structure have been analyzed by combining the statistical theory of ordering with the electronic theory of alloys in pseudopotential approximation. The partial ordering energies and pairwise SRO parameters were calculated by taking into account the influence of the first three coordination spheres. The results of calculation show that the atoms of Zn, Ti, Si, Mo or V elements substitute mainly for Al sublattice sites, whereas W, Nb, Ta, Hf, or Zr element atoms substitute preferentially for the Ni sublattice sites and Cr or Mn element atoms tend to substitute for both Ni and Al sublattice sites. These theoretical results are in a good qualitative agreement with experimental observations for most of the third component Me elements.
- Sponsoring Organization:
- TUBITAK (Turkey)
- OSTI ID:
- 483622
- Journal Information:
- Acta Materialia, Journal Name: Acta Materialia Journal Issue: 3 Vol. 45; ISSN 1359-6454; ISSN ACMAFD
- Country of Publication:
- United States
- Language:
- English
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