|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||NOW ON-DEMAND ONLY - The Impact of Al on the SRO, LRO, and Clustering of Elements within a CoFeNi High Entropy Alloy
||Jaimie S. Tiley, Soumya Nag, Ke An, Joerg Neuefeind, Jonathan Poplawsky, Sriswaroop Dasari, Rajarshi Banerjee
|On-Site Speaker (Planned)
||Jaimie S. Tiley
Microstructure evolution in a base equi-atomic CoFeNi alloy and samples containing 4, 8, and 12 at% Al was investigated using neutron scattering and diffraction coupled with TEM and APT. Al was specifically chosen since it has a large negative enthalpy of mixing with Ni, Fe, and Co, and therefore expected to introduce ordering tendencies (B2 structure). Previous solution thermodynamic modeling indicated the potential for forming phases within these materials that were stable at higher temperature. Select samples were cold rolled at 50 and 85% to provide heterogeneous nucleation sites, followed by water quenching. The resulting material was characterized at multiple length scales to identify probability distribution functions and chemical segregation. Results demonstrate the advantages of coupling multiple characterization techniques and illustrate the impact of Al on the short-range ordering and composition gradients within the alloy. In addition, the use multiple characterization methods identified strengths associated with coupling techniques.