Studying on High Temperature Plastic Deformation Behavior and Flow Softening of Novel Multiphase TiAl Alloy

被引：0
|
作者：
Han J. [1 ,2 ]
Yao H. [1 ,2 ]
Jia Y. [1 ,2 ]
Xie G. [3 ]
Wang T. [1 ,2 ]
机构：
[1] College of Mechanical and Vehicle Engineering, Taiyuan University of Technology, Taiyuan
[2] Engineering Research Center of Advanced Metal Composites Forming Technology and Equipment, Ministry of Education, Taiyuan University of Technology, Taiyuan
[3] State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang
来源：
Jixie Gongcheng Xuebao/Journal of Mechanical Engineering | 2022年 / 58卷 / 16期
关键词：
dynamic recrystallization; multiphase TiAl; phase transition; softening mechanism; thermoplastic deformation;
D O I：
10.3901/JME.2022.16.077
中图分类号：
学科分类号：
摘要：
Focusing on the poor hot-deformability of TiAl alloy, the thermal deformation behavior of Ti-40Al-6V-1Cr-0.3Ni at deformation temperature of 1 100-1 225 ℃, strain rate of 0.01-0.5 s−1 and engineering strain of 70% is studied by Gleeble-3800 thermal simulation test machine. The constitutive equation of the alloy is deduced based on the Arrhenius hyperbolic sinusoidal function model. The activation energy and stress index are 464.74 kJ/mol and 2.50 respectively, lower than that of the present deforming TiAl alloy. Based on the dynamic material model, the hot working diagram of the alloy with the engineering strain of 70% is established. The microstructure analysis results show that the multiphase TiAl alloy could fully recrystallize at high temperature and low strain rate, showing a similar behavior to that of the alloy with high stacking fault energy. The addition of β phase stable elements widen the hot working window of the alloy. β Phase plays an important role in relieving work hardening during high-temperature deformation. The full recrystallization and phase transformation decomposition of β phase should be the main ways to alleviate stress concentration. At the same time, it acted as a high-temperature lubricant to alleviate the stress at grain boundary and phase boundary and coordinate the difficult deformation α phase at high temperature. As a result, the thermoplastic deformation ability of the material is improved. According to the hot working diagram and microstructure feature, the appropriate deformation process parameters are proposed and successfully applied to the nearly isothermal forging of TiAl alloy. © 2022 Editorial Office of Chinese Journal of Mechanical Engineering. All rights reserved.
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页码：77 / 88
页数：11
相关论文
共 35 条
  • [21] KONG F T, CHEN Y Y，, LI B H, Et al., Influence of yttrium on the high temperature deformability of TiAl alloys[J], Materials Science and Engineering：A, 499, 1-2, pp. 53-57, (2009)
  • [22] MISHIN Y, HERZIG C., Diffusion in the Ti-Al system[J], Acta Materialia, 48, 3, pp. 589-623, (2000)
  • [23] Juqiang LI, Juan LIU, Zhenshan CUI, Characterization of hot deformation behavior of extruded ZK60 magnesium alloy using 3D processing maps[J], Materials and Design, 56, pp. 889-897, (2014)
  • [24] RAO K P，, PRASAD Y., Processing map and hot working mechanisms in a P/M TiAl alloy composite with in situ carbide and silicide dispersions[J], Materials Science and Engineering, 527, 24-25, pp. 6589-6595, (2010)
  • [25] LIU H, RONG R, GAO F, Et al., Hot deformation mechanisms of an as-extruded TiAl Alloy with large amount of remnant lamellae[J], Journal of Materials Engineering and Performance, 26, 7, pp. 3151-3159, (2017)
  • [26] XIN J, ZHANG L, Et al., Characterization of microstructure evolution in β-γ TiAl alloy containing high content of Niobium using constitutive equation and power dissipation map[J], Materials & Design, 107, pp. 406-415, (2016)
  • [27] DENQUIN A，, NAKA S., Phase transformation mechanisms involved in two-phase TiAl-based alloys-I. lamellar structure formation [J], Acta Materialia, 44, 1, pp. 343-352, (1996)
  • [28] SABINASH C M, SASTRY S, JERINA K L, Et al., High-temperature deformation of titanium aluminide alloys[J], Materials Science and Engineering：A, 192-193, pp. 837-847, (1995)
  • [29] SCHMOELZER T, LISS K, KIRCHLECHNER C, Et al., An in-situ high-energy X-ray diffraction study on the hot-deformation behavior of a β-phase containing TiAl alloy[J], Intermetallics, 39, pp. 25-33, (2013)
  • [30] WEN D，, ZONG Y, WANG Y, Et al., Positive influence of hydrogen on the hot workability and dynamic recrystallization of a γ-TiAl based alloy[J], Materials Science and Engineering, 656, pp. 151-164, (2016)
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