About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
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Advances in Multi-Principal Element Alloys II
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Presentation Title |
Oxidation of Group IV-V Refractory Multi-principal Element Alloys |
Author(s) |
Charlotte Brandenburg, David Beaudry, Michael Waters, Loïc Perrière, Jean-Philippe Couzinie, James Rondinelli, Mitra Taheri, Elizabeth J. Opila |
On-Site Speaker (Planned) |
Elizabeth J. Opila |
Abstract Scope |
Refractory multi-principal element alloys composed of Group IV (Ti,Zr,Hf) and Group V (Nb,Ta) metals are of interest for their potential high temperature capability, however, oxidation rates are rapid. Additions of common protective oxide formers Al, Cr, and Si lead to alloy embrittlement when added in sufficient amounts for oxidation resistance, thus other methods of increasing oxidation resistance are sought. In this work, the oxidation kinetics of equimolar NbTiZr and HfNbTaTiZr alloys are investigated using thermogravimetric analysis at temperatures between 900 and 1200°C in 1% oxygen (balance argon) for times up to 20 hours to understand fundamental oxidation mechanisms. Oxygen solubility varies in the alloy constituents resulting in phase separation into Group IV- and Group V-rich regions as interstitial oxygen content increases. X-ray diffraction analysis of the external oxide scales reveals complex oxides such as TiNb2O7 and Zr6Nb2O17 form. Compositional and/or microstructural explanations for observed reductions in oxidation rates are described. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Entropy Alloys, High-Temperature Materials, Other |