| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Computational Thermodynamics and Kinetics
|
| Presentation Title |
O-32: Thermodynamic Stability and Kinetics of Nb3Ge, Nb3Al, and Nb3Ga A15 Phases |
| Author(s) |
Ajinkya Hire, Hannah Bayard, Chris Orozco, Biswas Rijal, Lilong Zhu, Ryan Porter, Zeming Sun, Matthias Liepe, Michele Manuel, Richard Hennig |
| On-Site Speaker (Planned) |
Ajinkya Hire |
| Abstract Scope |
In superconducting radio frequency(SRF) cavities, Nb3Sn coating leads to shorter cavity lengths, higher operating temperatures and lower power consumption due to its high superheating-field. Nb3X(X=Ge,Ga,Al) A15-phases have higher superconducting temperature and field as compared to Nb3Sn and can be potential alternatives to Nb3Sn for SRF applications. In this work, we investigate the thermodynamic-stability and synthesis condition of these phases. We use density functional theory(DFT) and a cluster expansion-based approach to calculate the thermodynamic-stability range of these phases. We also perform diffusion couple experiments to validate the solubility limits and determine the interdiffusion-coefficients, an essential parameter in the synthesis of these phases. Furthermore, the superconducting properties of these materials are also determined using DFT and Eliashberg calculations. We find that Nb-antisite defects are the predominant defects which stabilize Nb3X at off-stoichiometric compositions. We also find differences between our calculated composition-ranges and the ranges in literature at which these phases are stable. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |