Autor: |
Ferrari, Alberto, Paulsen, Alexander, Langenkämper, Dennis, Piorunek, David, Somsen, Christoph, Frenzel, Jan, Rogal, Jutta, Eggeler, Gunther, Drautz, Ralf |
Rok vydání: |
2019 |
Předmět: |
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Zdroj: |
Phys. Rev. Materials 3, 103605 (2019) |
Druh dokumentu: |
Working Paper |
DOI: |
10.1103/PhysRevMaterials.3.103605 |
Popis: |
The rapid degradation of the functional properties of many Ti-based alloys is due to the precipitation of the $\omega$ phase. In the conventional high-temperature shape memory alloy Ti-Ta the formation of this phase compromises completely the shape memory effect and high (>100{\deg}C) transformation temperatures cannot be mantained during cycling. A solution to this problem is the addition of other elements to form Ti-Ta-X alloys, which often modifies the transformation temperatures; due to the largely unexplored space of possible compositions, very few elements are known to stabilize the shape memory effect without decreasing the transformation temperatures below 100{\deg}C. In this study we use transparent descriptors derived from first principles calculations to search for new ternary Ti-Ta-X alloys that combine stability and high temperatures. We suggest four new alloys with these properties, namely Ti-Ta-Sb, Ti-Ta-Bi, Ti-Ta-In, and Ti-Ta-Sc. Our predictions for the most promising of these alloys, Ti-Ta-Sc, are subsequently fully validated by experimental investigations, the new alloy Ti-Ta-Sc showing no traces of $\omega$ phase after cycling. Our computational strategy is immediately transferable to other materials and may contribute to suppress $\omega$ phase formation in a large class of alloys. |
Databáze: |
arXiv |
Externí odkaz: |
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