摘要
为了研究铝脱氧钙处理钢凝固冷却过程夹杂物的转变机理及影响因素,通过对S335结构钢中间包钢液和连铸坯取样,分析了不同洁净度钢中夹杂物的转变现象。结果表明,从中间包钢液到连铸坯夹杂物发生了由均相CaO-Al2O3向多相Al2O3+CaS的转变,同时伴随着夹杂物数量和尺寸的增加。通过热力学计算揭示了钢凝固冷却过程夹杂物的转变机理,并发现随着钢中w(T.[Ca])/w(T.[O])的减小和w(T.[O])/w(T.[S])的增大,钢液夹杂物中CaO质量分数减小,同时凝固冷却过程夹杂物中CaS的析出温度和析出量均减小。基于钢凝固冷却过程夹杂物的转变现象可知,在分析钢液中夹杂物成分时,须在取出钢水试样后进行快速冷却,以避免凝固冷却过程中夹杂物发生转变,提高检测的准确性。
In order to study the transformation mechanism and influencing factors of inclusions during the solidification and cooling process of aluminum deoxidized calcium treated steel,the transformation phenomenon of inclusions in steel with different cleanliness levels was analyzed by taking molten steel samples in tundish and continuous casting slab samples of S335 structural steel.It was found that during the production process of Al-killed Ca treated S335 structural steels,inclusions underwent a transformation from homogeneous CaO-Al2O3 to multiphase Al2O3+CaS from the molten steel in tundish to the continuous casting slab,accompanied by an increase in the number density and size of inclusions.The transformation mechanism of inclusions during the solidification and cooling process of steel was revealed through thermodynamic calculations.It was found that with the decrease of w(T.[Ca])/w(T.[O])and the increase of w(T.[O])/w(T.[S])in the steel,the weight percent of CaO in inclusions in the molten steel decreased.At the same time,the precipitation temperature and precipitation amount of CaS in inclusions decreased during the solidification and cooling process.Based on the transformation phenomenon of inclusions during the solidification and cooling of steels,it could be concluded that when analyzing the composition of inclusions in molten steel,rapid cooling must be carried out after taking out the molten steel sample to avoid the transformation of inclusions during the solidification and cooling process and improve the accuracy of detection.
作者
高江
王乐瑶
杨文
张立峰
李权辉
李明
GAO Jiang;WANG Leyao;YANG Wen;ZHANG Lifeng;LI Quanhui;LI Ming(Nangang Research Institute,Nanjing Iron and Steel Co.,Ltd.,Nanjing 210044,Jiangsu,China;School of Materials Science and Engineering,Yanshan University,Qinhuangdao 066004,Hebei,China;School of Metallurgical and Ecological Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Mechanical and Materials Engineering,North China University of Technology,Beijing 100144,China)
出处
《连铸》
北大核心
2024年第1期26-31,共6页
Continuous Casting
基金
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
S335结构钢
连铸
凝固冷却
夹杂物转变
洁净度
热力学
S335 structural steel
continuous casting
solidification and cooling
inclusion transformation
cleanliness
thermodynamic