About this Abstract |
Meeting |
2020 TMS Annual Meeting & Exhibition
|
Symposium
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High Entropy Alloys VIII
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Presentation Title |
J-21: Antiphase Boundaries in the B2 Matrix of the Al-Co-Cr-Fe-Ni High Entropy Alloy |
Author(s) |
Louisa Meshi, Lior Natovitz, Guy Hillel, Yatir Linden, Shai Salhov, Malki Pinkas |
On-Site Speaker (Planned) |
Guy Hillel |
Abstract Scope |
AlCoCrFeNi alloy solidifies in a dendritic regime with Al+Ni-rich dendrite (DR) and Fe+Cr-rich interdendrite (ID). Both areas are composed of ordered bcc (B2) matrix and bcc particles, displaying different morphology and hardness. We have found that the DR matrix contains ordered antiphase boundaries (APB). These AP domains arrest the growth of the bcc. In the ID area - short range order of the APBs was observed in the B2. There, bcc had characteristic Chinese letter-like (CL) morphology. Heat treatment at 850°C caused bcc->fcc+sigma transformation only in the ID; while DR remained essentially unchanged probably due to strain associated with the APB`s order. In our attempt to understand these phenomena, quaternary alloys, based on the quinary AlCoCrFeNi, were cast and characterized. CoCrFeNi and AlCoFeNi were single phase fcc and B2, respectively. AlCoCrFe exhibited fine CL bcc/B2 morphology with 720 HV hardness. AlCrFeNi and AlCoCrNi were similar to the quinary alloy. |
Proceedings Inclusion? |
Planned: Supplemental Proceedings volume; Planned: Supplemental Proceedings volume |