Abstract
Population density function (PDF), which can eliminate the arbitrariness caused by the choice of the number and the size of bins compared to the well-used histograms, was introduced to analyze the amount of inclusions. The population evolution of oxide inclusions in forms of PDF in Ti-stabilized ultra-low carbon steels after deoxidation during industrial RH refining and continuous casting processes was analyzed using an automated SEM-EDS system. It was found that after deoxidation till the early stage of casting, the alumina inclusions exhibited a lognormal PDF distribution, and three factors including the existence of a large amount of alumina clusters, the generation of alumina from the reduction of Al-Ti-O inclusions and the reoxidation of molten steel were estimated as the reasons. The shape parameter σ was high after deoxidation and then decreased after Ti treatment, indicating that in a short period after deoxidation, the size of alumina inclusions was widely distributed. After Ti treatment, the distribution of inclusion size was more concentrated. The scale parameter m decreased with time during the whole refining process, indicating that the proportion of large inclusions decreased during refining. Contrarily, the Al-Ti-O inclusions presented a fractal PDF distribution except at the end of casting with fractal dimension D of 4.3, and the constant of proportionality C decreased with time during RH refining and increased during casting process. The reoxidation of steel by slag entrapped from ladle was considered as the reason for the lognormal PDF behavior of Al-Ti-O inclusions at the end of casting.
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C. Wang, N. T. Nuhfer, S. Sridhar, Metall. Mater. Trans. B 40 (2009) 1022–1034.
C. Wang, N. T. Nuhfer, S. Sridhar, Metall. Mater. Trans. B 40 (2009) 1005–1021.
C. Wang, N. T. Nuhfer, S. Sridhar, Metall. Mater. Trans. B 41 (2010) 1084–1094.
H. Matsuura, C. Wang, G. Wen, S. Sridhar, ISIJ Int. 47 (2007) 1265–1274.
C. Bernhard, G. Xia, M. Egger, A. Pissenberger, S. K. Michelic, in: Proceedings of the 2012 Iron & Steel Technology Conference (Volume I), Association for Iron and Steel Technology, Warrendale, PA, 2012, pp. 2191–2200.
C. Wang, N. Verma, Y. Kwon, W. Tiekink, N. Kikuchi, S. Sridhar, ISIJ Int. 51 (2011) 375–381.
D. C. Park, I. H. Jung, P. C. H. Rhee, H. G. Lee, ISIJ Int. 44 (2004) 1669–1678.
W. C. Doo, D. Y. Kim, S. C. Kang, K. W. Yi, Met. Mater. Int. 13 (2007) 249–255.
M. Wang, Y. P. Bao, H. Cui, H. J. Wu, W. S. Wu, ISIJ Int. 50 (2010) 1606–1611.
C. Lyons, P. Kaushik, Steel Res. Int. 82 (2011) 1394–1403.
P. Kaushik, H. Pielet, H. Yin, Ironmak. Steelmak. 36 (2009) 561–571.
M. K. Sun, I. H. Jung, H. G. Lee, Met. Mater. Int. 14 (2008) 791–798.
M. A. Van Ende, M. Guo, R. Dekkers, M. Burty, J. Van Dyck, P. T. Jones, B. Blanpain, P. Wollants, ISIJ Int. 49 (2009) 1133–1140.
W. Yang, S. Li, Y. Li, X. Wang, L. Zhang, X. Liu, Q. Shan, in L. Zhang, A. Allanore, C. Wang, J. A. Yurko, J. Crapps (Eds.), Materials Processing Fundamentals, The Minerals, Metals & Materials Society, Warrendale, PA, 2013, pp. 3–16.
M. A. Van Ende, M. X. Guo, E. Zinngrebe, R. Dekkers, J. Proost, B. Blanpain, P. Wollants, Ironmak. Steelmak. 36 (2009) 201–208.
E. Zinngrebe, C. Van Hoek, H. Visser, A. Westendorp, I. H. Jung, ISIJ Int. 52 (2012) 52–61.
M. A. Van Ende, M. Guo, E. Zinngrebe, B. Blanpain, I. H. Jung, ISIJ Int. 53 (2013) 1974–1982.
M. D. Higgins, American Mineralogist 85 (2000) 1105–1116.
I. N. Bindeman, American Mineralogist 90 (2005) 1801–1815.
W. Yang, L. Zhang, X. Wang, Y. Ren, X. Liu, Q. Shan, ISIJ Int. 53 (2013) 1401–1410.
M. D. Higgins, CSD Corrections 1.40 [2015-03-15], https://doi.org/www.uqac.ca/mhiggins/csdcorrections.html.
M. D. Higgins, American Mineralogist 87 (2002) 171–175.
F. Ruby-Meyer, J. Lehmann, H. Gaye, Scand. J. Metall. 29 (2000) 206–212.
I. H. Jung, G. Eriksson, P. Wu, A. Pelton, ISIJ Int. 49 (2009) 1290–1297.
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Foundation Item: Item Sponsored by National Natural Science Foundation of China (51274034, 51334002, 51404019); Independent Research and Development Program from State Key Laboratory of Advanced Metallurgy of China
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Yang, W., Zhang, Y., Zhang, Lf. et al. Population Evolution of Oxide Inclusions in Ti-stabilized Ultra-low Carbon Steels after Deoxidation. J. Iron Steel Res. Int. 22, 1069–1077 (2015). https://doi.org/10.1016/S1006-706X(15)30114-X
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DOI: https://doi.org/10.1016/S1006-706X(15)30114-X