About this Abstract |
Meeting |
MS&T22: Materials Science & Technology
|
Symposium
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Alloy Phase Transformations at Elevated Temperatures
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Presentation Title |
Alternate Phase Transformation Paths in a Nb-50Ti Alloy in the Presence of Oxygen Interstitials |
Author(s) |
Ravit Silverstein, Anirudh R. Natarajan, Anton Van der Ven, Carlos G. Levi |
On-Site Speaker (Planned) |
Ravit Silverstein |
Abstract Scope |
Interstitials are well known to affect the phase stability and impact the performance of many structural alloys, including those based on BCC multi-principal elements (MPEs). As a part of a broader effort to understand the impact of interstitials in BCC refractory alloys, a study has been undertaken to address the role of relatively dilute concentrations of oxygen in a BCC equimolar Ti-Nb alloy. The study revealed that oxygen incorporation induces a miscibility gap within the BCC field, with potential for spinodal decomposition about the equimolar solution. The spinodal leads to modulation of Nb/Ti, with O redistributing preferentially to the Ti-rich regions. The latter then exhibits a primary transformation mechanism to HCP via a transient orthorhombic form, following the Burgers path. A secondary path through an intermediate omega phase is also observed. This presentation discusses the alternate paths and their current understanding. |