J Mater Sci Technol ›› 2010, Vol. 26 ›› Issue (12): 1071-1077.

• Modeling and Simulations • Previous Articles     Next Articles

Vibration Effects on the Structural Stability of Al-Ti Intermetallics by First-principles Calculations

Hui Zhang, Shaoqing Wang   

  1. Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China
  • Received:2009-11-09 Revised:2010-04-08 Online:2010-12-31 Published:2010-12-21
  • Contact: Hui Zhang
  • Supported by:

    the National Basic Research Program of China (No. 2006CB605103) and the National Natural Science Foundation of China (No. 50971119)

Abstract: The structural stability of the intermetallics AlTi3, Al2Ti, Al3Ti4 and Al3Ti in the Al-Ti system has been investigated using density functional theory (DFT) and density functional perturbation theory (DFPT). The calculated ground-state convex hull is in agreement with the experimental researches. Al3Ti4 (hP7) is metastable at 0 K and may be stabilized as the temperature increases due to the effects of the vibration entropy. For Al2Ti, r-Al2Ti is stable at 0 K and h-Al2Ti is stabilized by the vibration entropy at high temperatures. Al3Ti (tI16) is unstable considering vibration effects and Al3Ti (tI8) is the most stable structure at 0 K.

Key words: First-principles, Al-Ti, Vibration, Crystal structure