About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Lightweight Composites, Materials, and Alloys
|
| Presentation Title |
Detection of Li-rich Precipitates in Cu-3Ta using EELS |
| Author(s) |
Emma McCarthy, Ching-Heng Shiau, Joshua Smeltzer, Chad Hornbuckle, Kris Darling, Martin Harmer, Christopher Marvel |
| On-Site Speaker (Planned) |
Emma McCarthy |
| Abstract Scope |
The thermal stability of nanocrystalline Cu-Ta alloys is influenced by the type and morphology of nanoscale precipitates. Previous studies demonstrated that Li additions between 0.5-2at% to Cu-3Ta strongly modify precipitate morphology. However, prior work combining atom probe tomography and S/TEM imaging did not identify all Li-rich phases in the microstructure. In this work, aberration-corrected S/TEM electron energy loss spectroscopy (EELS) and imaging were used to directly resolve Li distribution and identify phases. Analysis of the EELS spectra revealed a shifted Li K-edge near ~60 eV, rather than the expected ~55 eV, enabling improved identification of Li-containing regions. This shift allowed for more accurate mapping of Li distribution, particularly in the 2at% Li alloy, where Li-rich regions were clearly resolved. These results demonstrate that Li plays a critical role in modifying particle morphology and interfacial structure, which is closely linked to enhanced mechanical properties. |