About this Abstract | 
  
   
    | Meeting | 
    2025 TMS Annual Meeting & Exhibition
       | 
  
   
    | Symposium 
       | 
    Advances in Multi-Principal Element Alloys IV: Mechanical Behavior
       | 
  
   
    | Presentation Title | 
    E-27: The Rule of Mixtures, A New Evans-Polanyi-Semenov
Relation, and Twinning Predictions for High Entropy Transition Metal Ceramics | 
  
   
    | Author(s) | 
    Marium Mostafiz  Mou, Tarek  Haque, Sam  Daigle, Donald  W. Brenner | 
  
   
    | On-Site Speaker (Planned) | 
    Marium Mostafiz  Mou | 
  
   
    | Abstract Scope | 
    
High entropy ceramics, with five or more equi-molar components on crystal sublattices, offer exceptional mechanical properties but are challenging to understand and predict. In this work, we employed first-principles calculations to investigate the {111} twinning properties of Group IVB, VB, and VIB high-entropy transition metal carbides. Our findings indicate that twin boundaries can be predicted using an optimized rule-of-mixtures based on the properties of individual metal carbide constituents near the twin plane. Additionally, we discovered that the unstable twin energy, a barrier along the ⟨112⟩{111} gamma surface slip path, can be related to the twinning and stacking fault energies via an Evans-Polanyi-Semenov(EPS) relation. Typically used to describe a linear relationship between activation energy and heat of reaction, this new application of the EPS relation provides analytical relations for twinnability as a function of valence electron concentration for these materials. | 
  
   
    | Proceedings Inclusion? | 
    Planned:  | 
  
 
    | Keywords | 
    High-Entropy Alloys, Mechanical Properties, Ceramics |