Numerical simulation of solidification and heat transfer of Q355B slab during continuous casting
ZHOU Guo-tao1, CHEN Jin2, HUANG Biao-cai2, YAN Wei1, LI Jing1
1. State Key Laboratory of Advanced Metallurgy,University of Science and Technology Beijing, Beijing 100083,China; 2. Fujian Sangang Minguang Co.,Ltd.,Sanming 365000,Fujian,China
Abstract：In order to solve the problem that the continuous casting parameters of Q355B slab in a steel plant do not match with each other when the casting speed is increased, ProCAST software was employed to establish the solidification heat transfer model of the slab, and the solidification characteristics of the slab under different continuous casting parameters were studied. The results show that the casting speed has the greatest influence on the slab solidification, followed by the specific water flow rate, and the smallest is superheat in the calculated range. With the increase of casting speed or the decrease of specific water rate or the increase of superheat, the slab temperature, the solidification end and the length of two-phase zone increase to different degrees except the shell thickness. In the actual production process,it is found that changing the casting speed billet production without changing the specific water volume and the position under light pressure, the three failed to effectively cooperate with each other, resulting in serious intermediate cracks. Based on simulation results, when the casting speed is increased to 1.0 m/min, the specific water flow rate is increased from 0.38 L/kg to 0.55 L/kg, as a result, the generation ratio of intermediate crack is reduced from 70% to about 11%, and the center segregation of slab above the level of C1.5 increases by 24.5%.
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2023, Vol. 42 
