|
|
High Temperature Deformation Behavior of 4340 Steel:Activation Energy Calculation and Modeling of Flow Response |
S V Sajadifar1,G G Yapici1,M Ketabchi2,B Bemanizadeh3 |
1. Mechanical Engineering Department, Ozyegin University, Istanbul 34794, Turkey 2. Mining and Metallurgical Engineering Department, Amirkabir University of Technology, Tehran 15875-4413, Iran 3. Islamic Azad University, Karaj Branch, Tehran 31485-313, Iran |
|
|
Abstract The 4340 steel is extensively utilized in several industries including automotive and aerospace for manufacturing a large number of structural components. Due to the importance of thermo-mechanical processing in the production of steels, the dynamic recrystallization (DRX) characteristics of 4340 steel were investigated. Namely, hot compression tests on 4340 steel have been performed in a temperature range of 900-1200 �� and a strain rate range of 0��01-1 s-1 and the strain of up to 0��9. The resulting flow stress curves show the occurrence of dynamic recrystallization. The flow stress values decrease with the increase of deformation temperature and the decrease of strain rate. The microstructure of 4340 steel after deformation has been studied and it is suggested that the evolution of DRX grain structures can be accompanied by considerable migration of grain boundaries. The constitutive equations were developed to model the hot deformation behavior. Finally based on the classical stress-dislocation relations and the kinematics of the dynamic recrystallization; the flow stress constitutive equations for the dynamic recovery period and dynamic recrystallization period were derived for 4340 steel, respectively. The validity of the model was demonstrated by demonstrating the experimental data with the numerical results with reasonable agreement.
|
Received: 12 June 2012
Published: 17 December 2013
|
|
|
|
[1] |
Jian-guo Chen,Yong-chang Liu,Chen-xi Liu,Bi-yu Yan,Hui-jun Li. Effects of tantalum on austenitic transformation kinetics of RAFM steel[J]. Chinese Journal of Iron and Steel, 2017, 24(7): 705-710. |
[2] |
Zhao-xia Shi,,*,Xiao-feng Yan,Chun-hua Duan,Jin-gui Song,Ming-han Zhao,Jue Wang. Hot deformation behavior of GH4945 superalloy using constitutive equation and processing map[J]. Chinese Journal of Iron and Steel, 2017, 24(6): 625-633. |
[3] |
Da-shan Sui,*,Hai-ming Zhang,Hong-yang Zhu,Zhe Zhu,Zhen-shan Cui. Effects of process parameters on fragment and refinement of millimeter-grade coarse grains for 316LN steel during hot cogging[J]. Chinese Journal of Iron and Steel, 2017, 24(5): 529-535. |
[4] |
Jin-liang Gao,*,Yan Qi,Ya-qin Li,Hong-wei Shang,Dong-liang Zhao,Yang-huan Zhang. Hydrogen storage thermodynamic and kinetic characteristics of PrMg12-type alloys synthesized by mechanical milling[J]. Chinese Journal of Iron and Steel, 2017, 24(2): 198-205. |
[5] |
Peng Zhou,,Qing-xian Ma,,*. Static recrystallization behavior of 25CrMo4 mirror plate steel during two-pass hot deformation[J]. Chinese Journal of Iron and Steel, 2017, 24(2): 222-228. |
[6] |
Dian-chen Feng,,Hao Sun,Zhong-hui Hou,,Dong-liang Zhao,Xi-tao Wang,Yang-huan Zhang,,*. Highly ameliorated gaseous and electrochemical hydrogen storage dynamics of nanocrystalline and amorphous LaMg12-type alloys prepared by mechanical milling[J]. Chinese Journal of Iron and Steel, 2017, 24(1): 50-58. |
|
|
|
|