|
|
|
| Microstructural features and precipitation behavior of Ti, Nb and V microalloyed steel during isothermal processing |
| Qi Zhou1 Zhuang Li2 Zhan-shan Wei2 Di Wu3 Jin-yu Li2 Zhen-yao Shao2 |
| 1 School of Environment and Chemical Engineering, Shenyang Ligong University, Shenyang 110159, Liaoning, China 2 College of Materials Science and Engineering, Shenyang Aerospace University, Shenyang 110136, Liaoning, China 3 State Key Laboratory of Rolling and Automation, Northeastern University, Shenyang 110004, Liaoning, China |
|
|
|
|
Abstract Thermal simulations of Ti, Nb and V microalloyed steel were conducted using a thermomechanical simulator, and the microstructural evolution and the precipitation behavior during isothermal processing were analyzed. The results show that with increasing holding time, the microstructural constituents change from the martensite and bainitic ferrites to granular bainite and polygonal ferrite. The maximum hardness is obtained for the specimen after isothermal holding for 5 s due to the martensite strengthening effect. The hardness of the specimen decreases after isothermal holding for 10 s, because the strengthening contribution of fine dispersed precipitates becomes weaker. The hardness values of the specimens increase and then remain high after isothermal holding for 60 and 600 s. This is attributed to the contribution of the interphase precipitation hardening to the hardness of the studied steel. The precipitates in the specimen are coarsened after isothermal holding for 3600 s, even though the coarsening is not remarkable. These precipitates are fcc (Ti, Nb)(N, C) particles and belong to the MX-type precipitates. The beneficial effects of precipitation strengthening are lost. The hardness decreases to a minimum hardness value due to the presence of large amounts of polygonal ferrite after isothermal holding for 3600 s. Relatively coarse precipitates are the primary origin of the hardness decrease.
|
|
|
|
|
|
| Cite this article: |
|
Qi Zhou,Zhuang Li,Zhan-shan Wei, et al. Microstructural features and precipitation behavior of Ti, Nb and V microalloyed steel during isothermal processing[J]. Journal of Iron and Steel Research International, 2019, 26(1): 102-111.
|
|
|
|
| [1] |
Neng-yong Ye, Ming Cheng, Shi-hong Zhang, Hong-wu Song, Hong-wei Zhou. Influence of delta phase precipitation on static recrystallization of cold-rolled Inconel 718 alloy in solid solution treatment[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2019, 26(2): 148-153. |
| [2] |
Hai-zhong Zheng, Sheng-hua Guo, Qin-hao Luo, Xiao-yong Shu, Gui-fa Li. Effect of shot peening on microstructure, nanocrystallization and microhardness of Ti–10V–2Fe–3Al alloy surface[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2019, 26(1): 52-58. |
| [3] |
Hai-feng Xu . Gui-lin Wu . Chang Wang . Jian Li . Wen-quan Cao. Microstructure, hardness and contact fatigue properties of X30N high nitrogen stainless bearing steel[J]. , 2018, 25(9): 954-967. |
| [4] |
Zhen Li . Dong-hui Wen . Yue Ma . Qing Wang . Guo-qing Chen . Rui-qian Zhang . Rui Tang . Huan He. Prediction of alloy composition and microhardness by random forest in maraging stainless steels based on a cluster formula[J]. , 2018, 25(7): 717-723. |
| [5] |
Hao-ran Cui ? Jian-ping Lai ? Qing-lin Pan ? Xiang-dong Wang. Effect of N and Zr on as-cast microstructure and properties after annealing of a high-speed steel[J]. , 2018, 25(4): 460-468. |
| [6] |
Chen-chong Wang, Chi Zhang Zhi-gang Yang Jie Su. Carbide precipitation and element distribution in high Co–Ni secondary hardening steel[J]. JOURNAL OF IRON AND STEEL RESEARCH,INTERNATIONAL, 2018, 25(3): 340-346. |
|
|
|
|
2019, Vol. 26 
