|About this Abstract
||2023 TMS Annual Meeting & Exhibition
||Advances in Titanium Technology
||Understanding the Role of Dual-phase Interface on the Alpha Precipitation in Metastable Beta Titanium Alloy
||Dian Li, Yufeng Zheng
|On-Site Speaker (Planned)
In metastable beta titanium alloys, alpha microstructure of different morphologies, size scales and distributions can be tuned via different phase transformation pathways. One non-conventional transformation pathway is the nucleation of fine scaled alpha precipitates associated with the pre-formed omega phase. For example, super-fined alpha microstructure with a number density of 35-40 Ct/μm2 can be achieved during slow heating and isothermal aging process. In this work, we studied the alpha nucleation at the pre-formed dual-phase interface between omega phase and beta matrix in a metastable beta Ti-5Al-5Mo-5V-3Cr (wt%, Ti-5553) alloy using isothermal aging treatment. When isothermally aged at 300°C, alpha nucleation occurs closely associated with the pre-formed isothermal omega phase that the alpha precipitates were observed at the omega/beta interface using diffraction contrast TEM and z-contrast aberration-corrected S/TEM. The role of dual-phase interface on the alpha precipitation will be presented. This work is supported by the National Science Foundation, grant CMMI-2122272.
||Titanium, Phase Transformations, Characterization