The mechanism and control measures research of hot charging crack
WANG Jian-Gang1,3，WANG Hao2,3，LI Ren-jie１，４，ZHANG Yuan1,3
1. School of Materials and Metallurgy，Inner Mongolia University of Science and Technology，Baotou 014010，Nei Mongol，China 2. State Key Laboratory of Advanced Metallurgy，University of Science and Technology Beijing，Beijing 100083，China 3. The Rare Earth Steel Plates Plant of Baotou Iron and Steel Co.，Ltd.，Baotou 014010，Nei Mongol，China ４. Baotou Steel Group Company Office，Baotou 014010，Nei Mongol，China
Abstract：Metallographic specimens were taken and analyzed from wide and heavy plate with small longitudinal cracks produced in hot charging and hot transferring process from Baotou Steel，and the results prove that defects have occur before hot rolling process. The mixed crystal structure appearing on the surface of high temperature slab in the heating furnace decreased plasticity of the grain boundary，so cracks occurred during the heating process and expand in the hot rolling process. After self-designed surface quenching devices were applied，surface temperature of hot transportation slab could be reduced to less than 650 ℃，the slab surface microstructure and integrated mechanical property were effectively improved，and crack initiation was avoided in hot transferring process. Ratio of wide and heavy plate adopting hot transferring process has increased from 30% at the beginning of the trial to 72%，consequently the manufacturing cost of production line could significantly decrease，delivery time was shorten and considerable economic benefits were brought to the enterprise.
王建钢１，３，王 皓２，３，李人杰１，４，张 沅 １，３. 热送裂纹产生机制及生产工艺控制研究[J]. 中国钢铁期刊网, 2017, 36(2): 22-26.
WANG Jian-Gang，，WANG Hao，，LI Ren-jie１，４，ZHANG Yuan，. The mechanism and control measures research of hot charging crack. Chinese Journal of Iron and Steel, 2017, 36(2): 22-26.
2017, Vol. 36 
