AUTHOR=Gai Jinyang , Cheng Jun , Li Jinshan , Du Zhaoxin , Zhang Wen , Yu Sen , Yu Zhentao TITLE=Hot Deformation Behavior of a Novel Near-β Titanium Alloy Ti-5.5Mo-6V-7Cr-4Al-2Sn-1Fe in (α+β) Phase Region JOURNAL=Frontiers in Materials VOLUME=6 YEAR=2020 URL=https://www.frontiersin.org/journals/materials/articles/10.3389/fmats.2019.00343 DOI=10.3389/fmats.2019.00343 ISSN=2296-8016 ABSTRACT=

The hot deformation behavior of a novel near-beta titanium alloy Ti-5.5Mo-6V-7Cr-4Al-2Sn-1Fe in (α+β) phase region in the temperature of 605~755°C and strain rate range of 10−3~10−1/s−1 was investigated on the Gleeble-3800 thermo-mechanical simulator. The results showed that the deformation parameters can have a significant influence on flow softening behavior and the microstructure evolution, as well as dynamic recrystallization is remarkable at temperature 755°C and strain rate 10−3s−1. The flow stress decreases with the increase of temperature and decrease of strain rate. With the rise of temperature and strain rate, the content of α phase gradually decreases. During the thermal deformation process, the α phase content decreases with the increase of the strain rate and the size of α phase decreases with increasing temperature. αGB is short rod or spherical. And α phase precipitated after short-term aging preferentially nucleated within the grains after aging treatment. Moreover, the thermal-mechanical process does not induce α phase generation compared to general heat treatment.