|About this Abstract
||2023 TMS Annual Meeting & Exhibition
||Advances in Titanium Technology
||Kinetically Induced Fine Secondary α-Ti phase Formation in a Novel As-cast Titanium Alloy
||Zhi Liang, Jiashi Miao, Xuejun Huang, Fan Zhang, James C. Williams, Alan A. Luo
|On-Site Speaker (Planned)
The formation of fine secondary hexagonal close packed (HCP) α-Ti precipitates provides major strengthening in a new cast titanium alloy. The phase transformation mechanisms from the body-centered cubic (BCC) β-Ti matrix to fine α phase in this new α-β titanium alloy were investigated experimentally and computationally using CALculation of PHAse Diagram (CALPHAD)-based thermodynamic and kinetic models. The discrete distribution of α precipitates was observed in the as-cast alloy with evidence of strong Fe partitioning. Two main size groups of α precipitates and the Fe partitioning were characterized using scanning electron microscopy, scanning transmission electron microscopy, and synchrotron-based small-angle X-ray scattering techniques. A hypothesis of Fe-partitioning driven α precipitate nucleation and growth was validated by precipitation simulation using TC-PRISMA with customized thermodynamic and kinetic descriptions. These results suggested a new titanium alloy design route involving high mobility elements and demonstrated the capability of CALPHAD-based modeling in titanium alloy design.
||Titanium, ICME, Phase Transformations