| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Thermodynamics and Kinetics of Alloys III
|
| Presentation Title |
Site preferences and ordering in Nb-Al-M (M = Ni or Cu) ternary Laves phases |
| Author(s) |
Wei Chen |
| On-Site Speaker (Planned) |
Wei Chen |
| Abstract Scope |
The properties of binary Laves phases can often be improved by incorporation of additional elements into the crystal structure. In some cases, only a ternary Laves phase exists in an alloy system but with a substantial homogeneity range. Knowledge of the site preference in these compositionally complex intermetallics is necessary to tune the properties for improved performance. The site preferences and substitutional ordering behavior of two ternary C14 Laves phases Nb(Al1-xNix)2 and Nb(Al1-xCux)2 are studied with first-principles cluster expansion and Monte Carlo simulations. At low alloying concentrations the alloying elements Ni and Cu have preferences for the 6h B-sites. At higher alloying concentrations (0.25), Cu atoms are distributed with a slight preference for the 6h B-sites, but the Ni atoms show higher preferences for the 2a B-sites. Drop-synthesis calorimetry experiments and first-principles calculations of formation enthalpies as a function of composition are found to be in good agreement. |
| Proceedings Inclusion? |
Planned: |