Effect of Cooling Pattern on Surface Microstructure of Slab
WANG Hai-bao1,2,ZHANG Jiong-ming1,ZHAO Xin-yu2,LIU Yang2,WANG Wen-jun2,ZHEN Xin-gang3
1. School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China 2. Shougang Research Institute of Technology, Beijing 100043, China 3. Shouqin Metal Material Co., Ltd., Qinhuangdao 066326, Hebei, China
Abstract：The samples of diameter 10 mm were made to simulate slab surface. The experiment was made to control the samples cooling at traditional cooling pattern and controlled cooling pattern respectively. Furthermore, the microstructure of transverse section was observed under a metallographic microscope to study the influence on microstructure of slab surface of cooling pattern. The experiment results are as follows: Using traditional cooling pattern, the microstructure is massive ferrite and pearlite by the side of the sample. The grain sizes are between 10-200μm. Moreover the microstructure is strip ferrite, acicular ferrite and pearlite at the center area, the grain sizes are bigger, and the microstructure is uneven. Under controlled cooling conditions, the microstructure is massive ferrite and pearlite. The grain sizes are between 9.36-12.25μm and that the grains are small and the microstructure is even. The controlled cooling pattern can promote refinement grains to increase the hot ductility of slab surface, which will have positive effect on avoiding the occurrence of surface transverse cracks.
王海宝 ，张炯明，赵新宇，刘洋，王文军，甄新刚. 冷却模式对铸坯表面组织的影响[J]. 钢铁, 2013, 48(4): 35-39.
WANG Hai-bao,,ZHANG Jiong-ming,ZHAO Xin-yu,LIU Yang,WANG Wen-jun,ZHEN Xin-gang. Effect of Cooling Pattern on Surface Microstructure of Slab. Iron and Steel, 2013, 48(4): 35-39.
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2013, Vol. 48 
