About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
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Advanced Characterization Techniques for Quantifying and Modeling Deformation
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Presentation Title |
Observation of As-Quenched DU-6wt%Nb Microstructure by
Transmission Kikuchi Diffraction |
Author(s) |
Christian Walters, Rodney McCabe, Matthew Schneider, Daniel Savage, Donald Brown, Elena Garlea, Sean R. Agnew |
On-Site Speaker (Planned) |
Christian Walters |
Abstract Scope |
When quenched sufficiently rapidly from its high-temperature γ (bcc) phase, depleted U-6wt%Nb adopts a monoclinic, highly twinned martensite phase known as α’’. Material in this condition is a high-temperature shape-memory alloy (SMA), and it can recover up to 7% tensile strain by heating into the γ phase. The as-transformed martensitic microstructure has previously been studied by transmission electron microscopy. Crystal orientation mapping techniques like EBSD have yielded valuable information about the as-transformed microstructures in other SMAs. However, the high density of nanoscale twins in as-quenched DU-6wt%Nb has posed challenges. The present study considers transmission Kikuchi diffraction (TKD) data acquired from samples prepared by focused ion beam. The TKD patterns were indexed with the open-source EMsoft software package, which implements a forward model-based ‘dictionary’ indexing approach. Using the MTEX toolbox for Matlab, we have quantified the twin boundary misorientations and mapped all 12 correspondence variants of α’’ martensite. |
Proceedings Inclusion? |
Planned: |
Keywords |
Characterization, Nuclear Materials, Modeling and Simulation |