Experiment on distribution characteristics of surface inclusions in IF steel continuous casting billet
ZHAO Cheng-lin;TANG Fu-ping;ZHU Xiao-lei;LIAO Xiang-wei;CHEN Dong;State Key Laboratory of Marine Equipment Made of Metal Material and Application;Iron and Steel Research Institutes of Ansteel Group;Ansteel Group Corporation;
Inclusions are important factors that affect the surface quality of IF steel. It is significant to determine the optimum cleaning depth of continuous casting billet in different states when the IF steel continuous casting slab is cleaned on-line flame automatically. The second pouring piece of slab,the steady casting billet and the transfer billet between head and second cans of IF steel was dealed with. A total of 28 analytical samples are equidistance divided along with the width direction of the inner and outer surfaces of the each casting,and the size of each specimen is 29 mm×21 mm×30 mm. The changes of morphology,quantity and maximum size of inclusions under different cleaning depth are studied. The results show that the number of inclusions which is 20-50 μm in the second piece of slab is decreased with the increase of the cleaning capacity,the number of inclusions which is larger than 50 μm is slightly increased,and the number of inclusions which is larger than 20 μm in the steady state and the transfer billet is slightly reduced. When the surface of the slab is not cleaned,the maximum inclusions on the surface of the three slabs are 500,200 and 200 μm respectively. If the critical dimension of the inclusions affecting the surface quality of the steel plate is 100 μm,the second slab cleaning depth should be 4-5 mm,the steady casting billet and the transfer billet should be 2 mm.
【CateGory Index】： TF777