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

Abstract

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].

Keywords

Ternary Interaction Cluster Variation Method BBBA Irregular Tetrahedron Natural Iteration Method 

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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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