|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Grain Boundaries and Interfaces: Metastability, Disorder, and Non-Equilibrium Behavior
||Exploring the Structure and Chemistry Contributions to Interfacial Segregation in NbMoTaW with High-throughput Atomistic Simulations
||Ian Geiger, Timothy Rupert
|On-Site Speaker (Planned)
The chemical complexity of multi-principal element alloys makes interfacial segregation difficult to predict. In this study, we use atomistic simulations of bicrystals to sample a variety of interfacial sites in NbMoTaW and explore emergent trends in local interfacial behavior. We study hundreds of bicrystals, using equilibrium and metastable configurations from pure materials as templates for subsequent doping, and study tens of thousands of grain boundary sites, to isolate a variety of local states. General segregation trends are reported, but more importantly, deviations from the mean behavior signal situations where local structural and chemical driving forces lead to interesting behavior. For example, incomplete depletion of Ta and W at low angle boundaries provides evidence of chemical pinning of these elements due to B2 ordering at low temperatures. Overall, this work highlights the complex interplay between local boundary structure and chemical short range ordering in multi-principal element alloys.
||High-Entropy Alloys, Computational Materials Science & Engineering, Modeling and Simulation