Abstract
The thermodynamic descriptions of the Hf-Si and Nb-Si systems were modified based on the critically assessed experimental phase equilibria and thermodynamic properties. Using the CALPHAD (CALculation of PHAse Diagram) approach, a thermodynamic description of the Nb-Hf-Si system was developed from the Hf-Si and Nb-Si systems modified in the present study and the Nb-Hf system from the literature. The parameters of all ternary phases were optimized using the experimentally measured 1500 °C isothermal section and the liquidus projection at the metal-rich region of the Nb-Hf-Si system. Comparison between the calculated results and the experimental measurements shows that the present modeling can provide a satisfactory account of the experimental information for the metal-rich region of the Nb-Hf-Si ternary phase diagram. The thermodynamic description of Si-rich corner has been obtained principally by extrapolation due to lack of experimental data.
| Original language | English |
|---|---|
| Pages (from-to) | 407-415 |
| Number of pages | 9 |
| Journal | Intermetallics |
| Volume | 11 |
| Issue number | 5 |
| DOIs | |
| State | Published - May 2003 |
| Externally published | Yes |
Funding
The authors would like to thank Dr. Y. Du and Dr. H. Liang for very constructive discussion. This research was sponsored by AFOSR under contracts # F49620-99-C-0026 with Dr. C. Hartley as the program manager.
| Funders | Funder number |
|---|---|
| Air Force Office of Scientific Research | F49620-99-C-0026 |
Keywords
- Intermetallics, miscellaneous
- Phase diagram
- Phase diagram prediction
- Silicides, various
- Thermodynamic properties