First-principles phase diagram calculations for the HfC–TiC, ZrC–TiC, and HfC–ZrC solid solutions
Abstract
We report first-principles phase diagram calculations for the binary systems HfC–TiC, TiC–ZrC, and HfC–ZrC. Formation energies for superstructures of various bulk compositions were computed with a plane-wave pseudopotential method. They in turn were used as a basis for fitting cluster expansion Hamiltonians, both with and without approximations for excess vibrational free energies. Significant miscibility gaps are predicted for the systems TiC–ZrC and HfC–TiC, with consolute temperatures in excess of 2000 K. The HfC–ZrC system is predicted to be completely miscibile down to 185 K. Reductions in consolute temperature due to excess vibrational free energy are estimated to be ~7%, ~20%, and ~0%, for HfC–TiC, TiC–ZrC, and HfC–ZrC, respectively. Predicted miscibility gaps are symmetric for HfC–ZrC, almost symmetric for HfC–TiC and asymmetric for TiC–ZrC.
Additional Information
© 2009 The American Physical Society. Received 27 March 2009; revised 3 August 2009; published 15 October 2009. This work was in part supported by the Graduate School "Oxides" in the Elite Netzwerk Bayern, funded by the State of Bavaria. The collaboration between GSN and AvdW has been supported by the Bavaria California Technology Center BaCaTeC. A.v.d.W. was supported by the U.S. National Science Foundation through TeraGrid resources provided by NCSA and SDSC under Grant No. TG-DMR050013N and by the U.S. Department of Energy National Nuclear Security Administration under Grant No.DE-FC52-08NA28613. We greatly appreciate helpful discussion with David Dolejš, Dan Frost, and Nico de Koker.Attached Files
Published - Adjaoud2009p6681Phys_Rev_B.pdf
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Additional details
- Eprint ID
- 17187
- Resolver ID
- CaltechAUTHORS:20100114-135951002
- Bavaria California Technology Center (BaCaTe)
- NSF
- National Center for Supercomputing Applications (NCSA)
- TG-DMR050013N
- San Diego Supercomputer Center (SDSC)
- DE-FC52-08NA28613
- U. S. Department of Energy National Nuclear Security Administratio
- Created
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2010-01-26Created from EPrint's datestamp field
- Updated
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2023-01-19Created from EPrint's last_modified field