| About this Abstract |
| Meeting |
2022 TMS Annual Meeting & Exhibition
|
| Symposium
|
Grain Boundaries and Interfaces: Metastability, Disorder, and Non-Equilibrium Behavior
|
| Presentation Title |
G-28: Investigation of the Effect of Heating Rate on the Recrystallization of Deformed Samples of Polycrystalline High-purity Niobium |
| Author(s) |
Zackery L. Thune, Nathan Fleming, Conor McKinney, Elizabeth Nicometo, Thomas R Bieler |
| On-Site Speaker (Planned) |
Zackery L. Thune |
| Abstract Scope |
The consistent production of high-purity niobium superconducting radiofrequency cavities is crucial for enabling improvements in accelerator performance. Currently, assembled cavities are vacuum heat-treated to 800°C for approximately three hours. Recent studies have shown that dislocations and grain boundaries trap magnetic flux which dissipates energy and degrades performance. Based on this understanding, the heat-treatment should reduce the number of dislocations and sub-grain boundaries. We hypothesize that the current heating rate is too slow and therefore facilitates recovery, rather than recrystallization, which does not reduce the number of geometrically necessary dislocations (GNDs) that are strongly correlated to trapped magnetic flux. For this study, vacuum heat-treatments at different heating rates were conducted and electron backscatter diffraction (EBSD) was used to investigate the effect of heating rate on the extent of recrystallization in samples of polycrystalline high-purity niobium from rolled sheets and formed cavities. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Characterization, Other, Other |