摘要
多模式薄板坯连续铸轧生产线(MCCR)既不同于传统连铸-轧制工艺,又异于传统薄板坯连铸连轧工艺,目前在国内外只有一条产线。MCCR工艺生产采用高拉速浇铸,具有大的通钢量,拉速对此工艺生产的轧板洁净度尤其是钢中非金属夹杂物特征影响较大。基于此,采用自动扫描电镜探究了4.7~5.2 m/min范围内拉速对MCCR工艺生产的低碳铝镇静钢轧板中非金属夹杂物特征的影响规律。结果表明,轧板中夹杂物主要为Al_(2)O_(3)-CaO类型,夹杂物中Al_(2)O_(3)质量分数为69%~72%、CaO质量分数为16%~22%,夹杂物成分随着拉速的增加基本不发生改变。轧板中5μm以上夹杂物随拉速的变化规律与2μm以上夹杂物随拉速的变化规律相反。随着拉速的增加,轧材中尺寸大于2μm夹杂物的数密度和面积分数整体呈小幅上升趋势,但平均尺寸变化不大。然而,随着拉速由4.7 m/min升高到5.0 m/min的过程,轧板中尺寸大于5μm夹杂物的数密度、面积分数和检测到的最大尺寸均呈现减小趋势,且在轧板宽度方向的波动也减小。拉速升至5.0 m/min以上后轧板中尺寸大于5μm夹杂物特征变化不大。从凝固前沿夹杂物受力的角度解释了钢中大尺寸夹杂物数量随拉速升高而降低的现象。基于研究结果,建议MCCR工艺生产低碳铝镇静钢时宜采用5.0 m/min以上的连铸拉速。
The multi-mode thin plate continuous casting and rolling(MCCR)production line is not only different from traditional continuous casting-hot rolling processes,but also from traditional thin plate continuous casting and rolling processes.Currently,there is only one MCCR production line in China and abroad.The MCCR process adopts high casting speed casting,which has a large steel throughput.The casting speed has a significant impact on the cleanliness of the rolled plates produced by this process,especially the characteristics of non-metallic inclusions in the steel.Based on this,in the current work,the effect of casting speed in the range of 4.7-5.2 m/min on the characteristics of non-metallic inclusions in rolled plates of a low carbon aluminum killed steel produced by MCCR process was investigated employing the automatic scanning electron microscopy.The results showed that the inclusions in the rolled plate were mainly Al_(2)O_(3)-CaO type,with the mass percent of Al_(2)O_(3)of 69%-72%and the mass percent of CaO of 16%-22%.The composition of inclusions was almost unchanged with the increase of casting speed.The characteristic evolution of>5μm inclusions in the plate with casting speed showed an opposite trend with that of>2μm inclusions.As the casting speed increased,the number density and area percent of>2μm inclusions in the rolled plate overall showed a slight upward trend,but the average size of inclusions changed little.However,as the casting speed increased from 4.7 m/min to 5.0 m/min,the number density,area percent,and detected maximum size of>5μm inclusions all showed a decreasing trend,and their fluctuation in the width direction of the rolled plate also decreased.While the characteristics of>5μm inclusions almost kept unchanged when the casting speed increased to over 5.0 m/min.The phenomenon that the number of large-sized inclusions in steel decreased with increasing casting speed was explained from the perspective of the forces on inclusions at the solidification front.Based on the results,it was
作者
杨文
王乐瑶
刘金刚
袁天祥
张立峰
杨光
李阳
闫占辉
YANG Wen;WANG Leyao;LIU Jingang;YUAN Tianxiang;ZHANG Lifeng;YANG Guang;LI Yang;YAN Zhanhui(School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;Research Institute of Technology,Shougang Group Co.,Ltd.,Beijing 100043,China;School of Mechanical Engineering,Yanshan University,Qinhuangdao 066004,Hebei,China;Manufacture Division,Shougang Jingtang Iron and Steel Co.,Ltd.,Tangshan 063200,Hebei,China;School of Mechanical and Materials Engineering,North China University of Technology,Beijing 100144,China;Steelmaking and Rolling Department,Shougang Jingtang Iron and Steel Co.,Ltd.,Tangshan 063200,Hebei,China)
出处
《钢铁》
CAS
CSCD
北大核心
2024年第8期50-57,93,共9页
Iron and Steel
基金
国家重点研发计划资助项目(2023YFB3709900,2023YFB3709903)
国家自然科学基金资助项目(52174293,U22A20171)
中央高校基本科研业务费资助项目(FRF-BD-20-04A)。
关键词
多模式连铸连轧
低碳铝镇静钢
高拉速
夹杂物
凝固前沿
multi-mode continuous casting and rolling
low carbon aluminum killed steel
high casting speed
inclusion
solidification front
