Hot Deformation Behavior of Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe Alloy in α + β Field

Metals

Zhaoxin Du¹  Shulong Xiao²  Jingshun Liu¹  Shufeng Lv¹  Lijuan Xu²  Fantao Kong²  Yuyong Chen² 

[1] School of Materials Science and Engineering, Inner Mongolia University of Technology, Hohhot 010051, China; E-Mails:;National Key Laboratory of Science and Technology on Precision Heat Processing of Metals, Harbin Institute of Technology, Harbin 150001, China; E-Mails:

关键词: β titanium alloys;    activation energy;    microstructure evolution;    deformation mechanism;   

DOI  :  10.3390/met5010216

来源: mdpi

【 摘 要 】

The deformation behavior of Ti-3.5Al-5Mo-6V-3Cr-2Sn-0.5Fe high strength β titanium alloy is systematically investigated by isothermal compression in α + β field with the deformation temperatures ranging from 1003 K to 1078 K, the strain rates ranging from 0.001 s⁻¹ to 1 s⁻¹ and the height reduction is around 50%. Essentially, the flow stress-strain curve of isothermal compression in α + β field exhibits a flow softening feature when the strain rate is higher than 0.1 s⁻¹ as while it exhibits a steady-state feature as the strain rate is lower than 0.1 s⁻¹. The peak stress increases with a decrease in deformation temperature and the increase of strain rate. The activation energy for deformation in α + β field was calculated and the average activation energy of 271.1 kJ/mol. The microstructure observation reveals that the isothermal deformation in the α + β field of the alloy is mainly controlled by the dynamic recovery mechanism accompanied with the secondary dynamic recrystallizitation of β phase. The α phase shows an obvious pinning effect for the movement of dislocations. During deformation, the α phase was elongated and fragmented.

【 授权许可】

CC BY   
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