摘要
某厂尝试采用全水型连铸机生产铌微合金化HRB400E钢螺纹钢用铸坯。但连铸坯产生了贯穿性的中心裂纹。为此对有中心裂纹的连铸坯进行了宏观和微观分析。结果表明:连铸坯中心裂纹主要是由于在连铸过程中二次冷却传热控制不当和铸坯凝固前沿受到矫直力作用所致。据此,优化了钢的成分,即控制铌和锰的含量,优化了连铸工艺参数,如二冷水量及其分配比、中间包过热度及拉速等,结果有效消除了铸坯的中心裂纹,轧材无开裂现象,螺纹钢质量得到了明显的改善。
Niobium-microalloyed HRB400E steel billet reserved for reinforced bar was trial-produced with the use of a full-water type continuous casting machine in a factory.However,the continuously cast billet offered penetrating crack in its center.For this reason,the continuously cast billet having center crack was subjected to macroscopical and microcoscopical examinations.The results indicated that formation of center crack in the billet stemmed largely from improper control of heat transfer in secondary cooling and from action of straightening force on its solidification front.In view of the above,optimization of chemical composition of the steel,i.e.,control of niobium and manganese contents,and majorization of the continuous casting process parameters such as volume and distribution ratio of secondary cooling water,superheat of tundish and casting speed,were carried out with the result that the center crack in the billet was effectively eliminated,rolled stock did not cracked,and the quality of reinforced bar was improved obviously.
作者
卢维枫
杨伟勇
王东兴
陶群南
汪春梅
黄雁
LU Weifeng;YANG Weiyong;WANG Dongxing;TAO Qunnan;WANG Chunmei;HUANG Yan(Wuhu Xinxing Casting Pipe Co., Ltd., Wuhu Anhui 241002, China)
出处
《上海金属》
CAS
北大核心
2020年第5期51-56,共6页
Shanghai Metals
