| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
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| Symposium
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Advances in Multi-Principal Element Alloys IV: Mechanical Behavior
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| Presentation Title |
Design of Ultra-Stable Nanocrystalline Multi-Element Alloy from the Coupled Effect of Self-Stabilization and Solute Grain Boundary Segregation |
| Author(s) |
Moses Awenbiik Adaan-Nyiak, Ahmed Alade Tiamiyu |
| On-Site Speaker (Planned) |
Moses Awenbiik Adaan-Nyiak |
| Abstract Scope |
The inherent thermal instability of nanocrystalline (NC) materials, even at low-temperatures, poses a fundamental limitation to their usage. Alloying with a solute-element to offset the excess grain boundary (GB) energy that is responsible for grain-growth is an effective metallurgical GB-stabilization means for NC-binary alloys. This approach is however considered complex for multi-principal element alloy (MPEA) systems. This talk will focus on our recent work that proposes and develops a novel NC-stabilization strategy for MPEAs—pseudo-binary-thermodynamic approach. This approach is guided by empirical rules and GB-segregation enthalpy considerations that identify Zr as solute-element that will segregate to the GBs of NC-AlCoCrFe-MPEA to stabilize it against grain-coarsening. NC-AlCoCrFe-MPEA with a minor addition of Zr is synthesized and heat treated up to 1123 K to experimentally-validate this approach. Employing in-situ XRD, S/TEM, and atom-probe tomography, significant thermal stability resulting from the self-stabilization and solute-GB-segregation effects is reported in NC-MPEAs at high homologous temperatures. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
High-Entropy Alloys, Mechanical Properties, Nanotechnology |