Study of phase equilibria in the Nb-Ti-Al system theoretical study: CVM calculation of the phase diagram of bcc Nb-Ti-Al

  • V. Chaumat
  • F. Moret
  • C. Colinet
Basic And Applied Research


The cluster variation method (CVM) in the irregular tetrahedron approximation has been used to calculate the temperature and composition limits of the ordered-cubic-centered B2 phase field in the Nb-Ti-Al system. Results show that this B2 domain is large and particularly extended toward the Nb-rich compositions. The order-disorder B2 → A2 transition temperature and the occupation probabilities of sites of the B2 phase are strongly dependent on composition that is in agreement with experimental results [98Cha].


Ternary Interaction Cluster Variation Method BBBA Irregular Tetrahedron Natural Iteration Method 


  1. 74Kikl:.
    R. Kikuchi and C.M. Van Baal, Phase Diagrams of fcc and bcc Ordered Alloys, Scr. Metall., Vol 8, 1974, p 425–430CrossRefGoogle Scholar
  2. 74Kik2:.
    R. Kikuchi, Superposition Approximation and Natural Iteration Calculation in Cluster Variation Method, J. Chem. Phys., Vol 60, 1974, p 1071–1080CrossRefADSGoogle Scholar
  3. 88Ben:.
    L.A. Bendersky and W.J. Boettinger, Investigation of B2 and Related Phases in the Ti-Al-Nb Ternary System, High-Temperature Ordered Intermetallic Alloy III (Boston, MA), 29 Nov–1 Dec 1988, Symposium Proceedings, Vol 133, Materials Research Society, 1989, p 45–50Google Scholar
  4. 89Ack:.
    H. Ackermann, G. Inden, and R. Kikuchi, Tetrahedron Approximation of the Cluster Variation Method for bcc Alloys, Acta Metall. Mater., Vol 37, 1989, p 1–7CrossRefGoogle Scholar
  5. 89Per:.
    J.H. Perepezko, Y.A. Chang, L.E. Seitzman, J.C. Lin, N.R. Bonda, T.J. Jewett, and J.C. Mishurda, High Temperature Phase Stability in the Ti-AlNb System, High Temperature Aluminides and Intermetallics (Indianapolis, IN), 1–5 Oct 1989, The Minerals, Metals & Materials Society, 1990, p 19Google Scholar
  6. 90Hel:.
    A. Hellwig, “Experimental Research of the Constitution of the Aluminum-Titanium-Niobium System,” Thesis, University Dortmund, 1990 (in German)Google Scholar
  7. 92Kat:.
    U.R. Kattner and W.J. Boettinger, Thermodynamic Calculation of the Ternary Ti-Al-Nb System, Mater. Sci. Eng., Vol 152, 1992, p 9–17CrossRefGoogle Scholar
  8. 92Men:.
    E.S.K. Menon, P.R. Subramanian, and D.M. Dimiduk, Phase Equilibria in Niobium Rich Nb-Al-Ti Alloys, Scr. Metall. Mater., Vol 27, 1992, p 265–270CrossRefGoogle Scholar
  9. 93Nak:.
    S. Naka, M. Marty, G. Lapasset, and T. Khan, Complex B2 Aluminides of Refractory Metals: An Attempt to Explore Novel Alloy System, First International Symposium on Structural Intermetallics (Champion, PA), 26–30 Sept 1993, The Minerals, Metals & Materials Society, 1993, p 647–656Google Scholar
  10. 93Shy:.
    J. Shyue, D.H. Hou, S.C. Johnson, and H.L Fraser, Phase Stability, Deformation Mechanisms and Mechanical Properties of Nb-Al-Ti Alloys, First International Symposium on Structural Intermetallics (Champion, PA), 26–30 Sept 1993, The Minerals, Metals & Materials Society, 1993, p 631–635Google Scholar
  11. 94Kum:.
    S.G. Kumar, R.G. Reddy, and L. Brewer, Phase Equilibrium in Ti3Al-Nb Alloys at 1000°C, J. Phase Equilibria, Vol 15 (No. 3), 1994, p 279–284CrossRefGoogle Scholar
  12. 95Ast:.
    M. Asta, A. Ormeci, and J.M. Wills, First-Principles Study of Intermetallic Phase Stability in the Ternary Ti-Al-Nb Alloy System, High-Temperature Ordered Intermetallic Alloys VI (Boston, MA), 28 Nov–1 Dec 1994, Symposium Proceedings, Vol 364, Materials Research Society, 1995, p 157–162Google Scholar
  13. 95Nak:.
    S. Naka, M. Marty, M. Thomas, and T. Khan, Variation in the Degree of Order and Its Influence on Mechanical Behavior in Complex B2 Aluminides of Refractory Metals, Mater. Sci. Eng., Vol A192/193, 1995, p 69–76Google Scholar
  14. 95Rub:.
    G. Rubin and A. Finel, Application of First-Principles Methods to Binary and Ternary Alloy Phase Diagram Predictions, J. Phys., Condens. Matter., Vol 7, 1995, p 3139–3152CrossRefADSGoogle Scholar
  15. 95Sik:.
    T. Sikora, G. Hug, M. Jaouen, and A.M. Flank, EXAFS Study of the Local Atomic Order in Ti2AlX (X=Nb, Mo), J. Physique, Vol 4 (No. 2), 1996, p 15–20 (in French)Google Scholar
  16. 96Cha:.
    V. Chaumat-Jacob, “Phase Equilibria and Microstructures in Nb-Ti-Al Alloys Prepared by Mechanical Alloying,” Thesis, INPG, Grenoble, France, 1996, (in French)Google Scholar
  17. 96Col:.
    C. Colinet and V. Jacob, Effect of Ternary Interactions on the B2/A2 Phase Boundary in the Nb-Ti-Al System, J. d’Etudes Equil. Phases, 15–16 April 1996 (in French)Google Scholar
  18. 96Sad:.
    F.A. Sadi and C. Servant, Transformations during Continuous Cooling of the Ti4Al3Nb Alloy, J. Phys., Vol 4 (No. 2), 1996, p 241–246 (in French)Google Scholar
  19. 97Col:.
    C. Colinet, A. Pasturel, D. Nguyen Manh, D.G. Pettigor, and P. Miodownick, Phase-Stability Study of the Al-Nb System, Phys. Rev. B, Vol 56 (No. 2), 1997, p 552–565CrossRefADSGoogle Scholar
  20. 97Hou:.
    D.-H. Hou and H.L. Fraser, The Ordering Scheme in Nb Aluminides with the B2 Crystal Structure, Scr. Mater., Vol 36 (No. 6), 1997, p 617–623CrossRefGoogle Scholar
  21. 97Sad:.
    F.A. Sadi, “Contribution to the Study of the Al-Nb-Ti Phase Diagram near the AlNbTi2 and Al3NbTi4 Compounds,” Thesis, Université Paris, Orsay, France, 1997 (in French)Google Scholar
  22. 98Cha:.
    V. Chaumat, E. Ressouche, B. Ouladdiaf, P. Desré, and F. Moret, Experimental Study of Phase Equilibria in the Nb-Ti-Al System, Scr. Mater., (in press)Google Scholar

Copyright information

© ASM International 1999

Authors and Affiliations

  • V. Chaumat
    • 1
  • F. Moret
    • 1
  • C. Colinet
    • 2
  1. 1.CEA/CEREM/DEM—Service of Materials EngineeringGrenoble cedex 9France
  2. 2.ENSEEG. LTPCMSaint Martin d’HèresFrance

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