About this Abstract | 
  
   
    | Meeting | 
    2025 TMS Annual Meeting & Exhibition
       | 
  
   
    | Symposium 
       | 
    Elucidating Microstructural Evolution Under Extreme Environments
       | 
  
   
    | Presentation Title | 
    F-1: Advanced In-Situ Strain Mapping for Zr Oxidation by Precession-Assisted 4D-STEM | 
  
   
    | Author(s) | 
    Yongwen  Sun, Ying  Han, Dan  Zhou, Athanassios S. Galanis, Alejandro  Gomez-Perez, Starvos  Nicolopoulos, Hugo Perez Garza, Yang  Yang | 
  
   
    | On-Site Speaker (Planned) | 
    Yongwen  Sun | 
  
   
    | Abstract Scope | 
    
Zirconium alloy fuel cladding undergoes oxidation during reactor operations, which is a primary life-limiting degradation mechanism. Effective strain mapping is important to understand the evolution of strain, aiding in the development of oxidation-resistant alloys. This study introduces an in-situ strain and orientation/phase mapping technique with nanometer resolution to investigate the initial zirconium oxidation in a high-temperature gas environment. This method combines precession-assisted four-dimensional scanning transmission electron microscopy (4D-STEM), a gas-cell holder, and a direct electron detector (DED). The key to successful strain and orientation/phase mapping relies on maintaining a high signal-to-noise ratio and minimizing dynamic effects in nanobeam electron diffraction patterns. We will explore the impact of gas pressure, electron beam precession, and methods to put the reactions on-hold. Our method achieves high-quality strain and orientation/phase mapping at nanometer resolution over a large field of view during oxidation, providing valuable insights into the chemo-mechanical evolutions of materials under extreme conditions. | 
  
   
    | Proceedings Inclusion? | 
    Planned:  | 
  
 
    | Keywords | 
    Nuclear Materials, Characterization, Phase Transformations |