| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Environmental Degradation of Multiple Principal Component Materials
|
| Presentation Title |
Improvement of Complex Oxide Properties by Doping |
| Author(s) |
Bronislava Gorr, Bjoern Schaefer, Steven Schellert, Hans Juergen Christ, Alexander Kauffmann, Martin Heilmaier |
| On-Site Speaker (Planned) |
Bronislava Gorr |
| Abstract Scope |
Refractory High Entropy Alloys (RHEA) are considered novel promising high temperature materials for structural applications at ultra-high temperatures. While many RHEA suffer from poor oxidation resistance similar to that of pure refractory metals, some RHEA exhibit very good protectiveness which is attributed to the formation of rarely encountered complex oxides such as (Cr,Ta,Ti)O2. This oxide exhibits high thermodynamic stability as well as the slow growth rate in the temperature range from 900 to 1200°C. However, a thick zone of internal corrosion formed underneath the oxide layer indicates that gaseous species such as oxygen and nitrogen can diffuse through the complex oxide. It is assumed that the rutile-type (Cr,Ta,Ti)O2 grows due to the inward diffusion of oxygen via oxygen vacancies. The minor additions of higher valency cations seem to reduce the concentration of oxygen vacancies leading to thinner (Cr,Ta,Ti)O2 scales and less pronounced internal corrosion. |
| Proceedings Inclusion? |
Planned: |