Investigations of Inclusion Modification in High Grade Pipeline Steel
SiCa line was injected into liquid pipeline steel at the end of LF refining as calcium treatment, and samples were taken from liquid steel in ladles before and after calcium treatment, liquid steel in mould, and slabs. Results show that Ca content in steel decreased obviously after calcium treatment with production, and the compositions, morphologies and sizes of inclusions in steel also varied with time; A12O3 inclusions turned to be fine irregular CaS-CaOAl2O3 compound inclusions after calcium treatment, and then to be fine globular CaO-Al2O3 inclusions in mould, and finally changed to be a few larger irregular CaS-CaO-AI2O3 complex inclusions in slabs; reoxidation of molten steel treated by Ca deteriorates effect of calcium treatment. Thermodynamic study revealed that inclusion variations were related with preferential reactions among Ca, AI2O3 and S and precipitation of S in high sulfur capacity CaO-Al2O3 inclusions. New calcium treatment controlling rules were put forward according to the inclusion variations and requirements of pipeline on inclusion controlling.
pipeline steel inclusion modification calcium treatment
LIUJian-hua BAOYan-ping WANG Ming RENYi ZHANG Shuai WANG Shuang
Institute of Metallurgical Engineering, University of Science and Technology Beijing, Beijing 100083 Technology Center of ANSC, Angang Steel Company Limited, Anshan 114001, Liaoning, China
国际会议
The 2nd International Symposium on Clean Steel(第二届洁净钢生产技术学术研讨会)
沈阳
英文
358-364
2011-08-23(万方平台首次上网日期,不代表论文的发表时间)