Effect of casting speed on solidification structure and carbon segregation of 40CrA bloom
SHEN Kunrui1, WANG Chen1, WANG Chao2, ZHOU Wenhao3, YANG Wenzhi3, CHEN Botao3, LIU Qing1
1. School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing, Beijing 100083,China; 2. School of Advanced Engineers, University of Science and Technology Beijing, Beijing 100083, China; 3. Xiangtan Iron and Steel Co., Ltd., Hunan Valin, Xiangtan 411101, Hunan,China
Abstract：The celluar automation finite element(CAFE) model and solidification heat transfer mathematical model were established to improve the problem of carbon segregation in the current continuous casting conditions of 40CrA bloom. And the influence of casting speed change on the solidification structure and microstructure of the bloom was studied. The simulation results show that, when the casting speed is 0.55 m/min, CET(columnar crystal structure to equiaaxial crystal transformation) starts from 69 mm away from the surface of the casting blank and ends at 122 mm away from the surface of the casting blank. When the casting speed is 0.59 m/min, the density of columnar crystal and equiaxed crystal is best. Combined with the industrial test, the results show that when the casting speed increases from 0.55 m/min to 0.59 m/min, the range of carbon segregation index decreases from 0.15 to 0.10, the fluctuation range decreases by 33.3%, the distribution of carbon content is more uniform, and the quality of billet is obviously improved.
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2023, Vol. 42 
