|
|
|
| Effects of Mn and Cr contents on microstructures and mechanical properties of low temperature bainitic steel |
| Hui Guo1,Peng Zhou2,*,Ai-min Zhao1,2,Chao Zhi2,Ran Ding2,Jia-xing Wang2 |
1 Collaborative Innovation Center of Steel Technology, University of Science and Technology Beijing, Beijing 100083, China
2 Institute of Engineering Research, University of Science and Technology Beijing, Beijing 100083, China |
|
|
|
|
Abstract The effects of Mn and Cr contents on bainitic transformation kinetics, microstructures and mechanical properties of high-carbon low alloy steels after austempered at 230, 300 and 350��C were determined by dilatometry, optical microscopy, scanning electron microscopy, X-ray diffraction and tensile tests. The results showed that Mn and Cr can extend bainitic incubation period and completion time, and with the increase of Mn and Cr content, the bainitic ferrite plate thickness decreased and the volume fraction of retained austenite increased. TRIP (transformation induced plasticity) effect was observed during tensile testing which improved the overall mechanical property. The increase of Mn concentration can improve the strength to a certain extent, but reduce the ductility. The increase of Cr concentration can improve the ductility of bainitic steels which transformed at a low temperature. The low temperature bainitic steel austempered at 230��C exhibited excellent mechanical properties with ultimate tensile strength of (2146��11) MPa and total elongation of (12.95��0.15) %.
|
|
Received: 12 July 2016
Published: 20 March 2017
|
| Fund:Natural Science Foundation of China;Natural Science Foundation of China |
|
|
|
| [1] |
Hao Li,Yan-chong Yu,,Xiang Ren,Shao-hua Zhang,She-bin Wang,,*. Evolution of Al2O3 inclusions by cerium treatment in low carbon high manganese steel[J]. Chinese Journal of Iron and Steel, 2017, 24(9): 925-934. |
| [2] |
Xiao-li Zhao,,Yong-jian Zhang,Cheng-wei Shao,Wei-jun Hui,Han Dong. Thermal stability of retained austenite and mechanical properties of medium-Mn steel during tempering treatment[J]. Chinese Journal of Iron and Steel, 2017, 24(8): 830-837. |
| [3] |
Ying-yi Zhang,Wei Lv,Xue-wei Lv,Chen-guang Bai,Ke-xi Han,Bing Song. Oxidation kinetics of ilmenite concentrate by non-isothermal thermogravimetric analysis[J]. Chinese Journal of Iron and Steel, 2017, 24(7): 678-684. |
| [4] |
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. |
| [5] |
Hong-huan Mao,Xing Qi,Jing Cao,Li-cong An,Yi-tao Yang*. Effect of Si on high temperature oxidation of 30Cr13 stainless steel[J]. Chinese Journal of Iron and Steel, 2017, 24(5): 561-566. |
| [6] |
Yang-huan Zhang,,*,Zhong-hui Hou,,Ying Cai,Hong-wei Shang,Yan Qi,Dong-liang Zhao. Structures and electrochemical performances of as-cast and spun RE-Mg-Ni-Mn-based alloys applied to Ni-MH battery[J]. Chinese Journal of Iron and Steel, 2017, 24(3): 296-305. |
|
|
|
|
2017, Vol. 24 
