Abstract：As an innovative and green steel production process,the direct rolling process of continuous casting steel is mainly used in the production of the ultra-thin hot-rolled strip,wire,and bar. Recently,the exploratory work on the direct rolling process of the hot-rolled plate has been started at home and abroad. The direct rolling process has a different temperature changing process and physical metallurgical process compared with the conventional hot rolling process. The Nb-Ti microalloyed steel was selected as the research object. From the aspect of microstructure and properties, the feasibility of the direct rolling process for the hot-rolled plate was studied by the integration experiment of steelmaking,continuous casting,and rolling process. The microstructure and properties of the hot-rolled plates under the direct rolling process and the conventional hot rolling process were compared. The grain refinement mechanism of the experimental steel under the direct rolling process was also discussed. The results show that the large temperature gradient in the direct rolling process is beneficial to the penetration of deformation towards the core,which is conducive to the dynamic recrystallization of the core. As a result,despite the lack of γ-α-γ phase transition before rolling,the microstructure and mechanical properties of the hot-rolled plate under the direct rolling process are similar and even better than those under the conventional rolling process.
李海军, 李天祥, 李睿昊, 王昭东, 王国栋. 直接轧制工艺对中厚板组织与性能的影响[J]. 钢铁, 2021, 56(4): 64-69.
LI Hai-jun, LI Tian-xiang, LI Rui-hao, WANG Zhao-dong, WANG Guo-dong. Effect of direct rolling process on microstructure and mechanical properties of hot-rolled steel plate[J]. Iron and Steel, 2021, 56(4): 64-69.
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2021, Vol. 56 
