| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
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High Entropy Materials: Concentrated Solid Solutions, Intermetallics, Ceramics, Functional Materials and Beyond V
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| Presentation Title |
Influence of Co, Cr, and Ni Alloying Elements on the Microstructural, Oxidation and Mechanical behavior of NbTi-Based Alloys |
| Author(s) |
Ugochukwu Philip Ochieze, Likun Sun, Nicholas Simpson, Sravya Josyula, Matthew Steiner, Eric Payton |
| On-Site Speaker (Planned) |
Ugochukwu Philip Ochieze |
| Abstract Scope |
Medium-entropy alloy systems with the potential to exhibit protective oxide films, high strength and ductility were explored in this study, with emphasis on the microstructural evolution, oxidation behavior and mechanical properties of NbTi-based alloys containing 5-10 at% Co, Cr, and Ni. Predictions from CALPHAD suggest that this composition range can be heat treated to obtain predominantly body-centered cubic matrix. However, results obtained via analytical microscopy show that the addition of 10 at% Cr to NbTi resulted in two bcc phases up to 1050 °C. All alloys exhibit mechanical softening between room temperature and 800 °C, with high flow stresses at 400 °C. All alloys exhibited good ductility, with some alloys exhibiting potentially superplastic behavior. From the discontinuous oxidation tests results, NbTi-10Ni and NbTi-5Co exhibited parabolic oxidation kinetics while NbTi-10Cr and NbTi-10(CoCrNi) had linear oxidation kinetics, though NbTi-10Cr exhibited a sluggish linear oxidation at 800 °C. |