|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Phase Transformations and Microstructural Evolution
||On the Precipitation Behavior of γ-TiAl from a Supersaturated βo-TiAl Matrix in an Intermetallic Ti-44Al-7Mo (at.%) Alloy
||Gloria Graf, Christoph Gammer, Simon Fellner, Johanna Byloff, David Holec, Helmut Clemens, Petra Spoerk-Erdely
|On-Site Speaker (Planned)
As lightweight materials with excellent high-temperature properties, intermetallic γ-TiAl based alloys have recently become well established in the aviation industry. In this work, the focus lies on the Ti-44Al-7Mo (in at.%) alloy. Molybdenum, as an alloying element, strongly stabilizes the β/βo phase and yields a (βo + γ) phase-field region at ambient temperatures. Consequently, the precipitation behavior of γ from an ordered βo matrix can be investigated, which is not possible for conventional alloys and therefore not yet well understood. Previous differential scanning calorimetry and high-energy X-ray diffraction investigations raised the questions whether the precipitation of γ-TiAl is preceded by the formation of an intermediate phase and whether the precipitate’s interface type changes during the process. With high-resolution transmission electron microscopy and ab-initio calculations it was proven that the interfaces are first coherent and slowly become incoherent with increasing precipitate radius. No intermediate phase is formed.
||High-Temperature Materials, Phase Transformations, Other