Optimization of Soft Reduction Process for Q345B Thick Slab
MA Jian-chao1,GUI Zhong-lin1,SU Du-xing1,XIA Qi1,XIA Weng-wei2,WANG Zhi-fu3
（1. Steelmaking and Casting Group, Institute of Research of Iron and Steel of Jiangsu Shasteel, Zhangjiagang 215625, Jiangsu, China 2. Hongfa Steelmaking Plant, Jiangsu Shasteel Co., Ltd., Zhangjiagang 215625, Jiangsu, China 3. Chief Engineer Office, Jiangsu Shasteel Co., Ltd., Zhangjiagang 215625, Jiangsu, China）
Abstract：Center separation defect of Q345B thick plates was investigated. The results show that the heavy center porosity carried over from continuous cast 320mm thick mother slabs is the key reason for center separation defect. Analysis on soft reduction for the slabs indicates that the actual crater end is further down the strand than the calculated position from previous online solidification model, and hence, the reduction ratio is insufficient at the final stage of solidification to compensate the final solidification shrinkage. Based on the investigation and analysis, the soft reduction scheme is optimized by extending soft reduction range and increasing the reduction ratio at the final solidification stage. After the optimization, center porosity and center segregation in the slabs are alleviated, and the center separation defect in the thick Q345B plates is resolved.
马建超，桂仲林，苏笃星，夏奇，夏翁伟，王志福. Q345B厚板坯连铸轻压下工艺的优化[J]. 钢铁, 2012, 47(4): 38-41.
MA Jian-chao1,GUI Zhong-lin1,SU Du-xing1,XIA Qi1,XIA Weng-wei2,WANG Zhi-fu3. Optimization of Soft Reduction Process for Q345B Thick Slab. Iron and Steel, 2012, 47(4): 38-41.
2012, Vol. 47 
