|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Advances in Titanium Technology
||Role of Defects in Alpha Precipitation in Metastable Beta Ti-5Al-5Mo-5V-3Cr Alloy
||Dian Li, Wenrui Zhao, Stoichko Antonov, Yufeng Zheng
|On-Site Speaker (Planned)
The mechanical performance of beta titanium alloys can be optimized by tuning hcp structured alpha precipitates in a matrix of bcc beta phase. Our previous study in Ti-5Al-5Mo-5V-3Cr (wt%, Ti-5553) has shown that fine-scale alpha microstructure can be generated, in which the pre-formed omega/beta interface may act as favorable nucleation sites for alpha precipitation. In this work, the role of other defects including dual-phase interface, twin boundary and grain boundary in tuning alpha precipitation in the metastable beta Ti-5553 alloy is studied using SEM, TEM, APT and FIB-SEM tomography. Fine-scale alpha precipitates form from pre-formed O”/beta interface; coarse alpha precipitates form along pre-formed twin boundary; while thick alpha layer forms from the grain boundary alpha. The possible microstructure evolution pathway to generate hierarchical alpha microstructure in Ti-5553 will be introduced.
||Titanium, Phase Transformations, Characterization