About this Abstract | 
  
   
    | Meeting | 
    2025 TMS Annual Meeting & Exhibition
       | 
  
   
    | Symposium 
       | 
    Powder Materials Processing and Fundamental Understanding
       | 
  
   
    | Presentation Title | 
    Metallurgical Evaluation of Near-Canister Degradation of Charpy Toughness Observed in Low Alloy Steel Billets Produced by PM-HIP | 
  
   
    | Author(s) | 
    Bryan D. Miller, Eric J Sload, Terrance K. Nolan, Colin D Ridgeway | 
  
   
    | On-Site Speaker (Planned) | 
    Bryan D. Miller | 
  
   
    | Abstract Scope | 
    
Powder metallurgy - hot isostatic pressing (PM-HIP) is being evaluated for production of pressure vessel components for small modular reactor (SMR) applications.  Extensive material testing of a low alloy steel (A508 Grade 4N) has previously identified the material is subject to a variation in Charpy impact toughness through the thickness of billets produced by PM-HIP practices.  To understand the source of this variation, an extensive metallurgical evaluation was performed to compare the microstructure of the near-canister material (with lowest Charpy toughness) to that of the interior canister material (with highest Charpy toughness).  Utilizing a combination of materials characterization techniques, two metallurgical factors were identified that could impact Charpy toughness:  the formation of oxide particles on prior austenite grain boundaries and the formation of a non-uniform grain size distribution.  Potential causes/remedies for each of these factors will be discussed. | 
  
   
    | Proceedings Inclusion? | 
    Planned:  | 
  
 
    | Keywords | 
    Iron and Steel, Characterization, Mechanical Properties |