METALS AND METAL MATRIX COMPOSITES |
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Effect of B2O3 on Properties and Structure of CaO-Al2O3-SiO2 Continuous Casting Mold Flux |
WANG Xingjuan1,2, JIN Hebin1,2, ZHU Liguang1,2, PIAO Zhanlong2,3, WANG Bo1,2, QU Shuo1,2
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1 College of Metallurgy and Energy, North China University of Science and Technology, Tangshan 063210 2 Hebei Engineering Research Center of High Quality Steel Continuous Casting, Tangshan 063000 3 School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083 |
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Abstract In this study, thermodynamics software was employed to calculate the ternary phase diagram of CaO-Al2O3-SiO2 and the quaternary phase diagram of CaO-Al2O3-B2O3-SiO2 first. Then, the specific contents of the main components of B2O3 and CaO-Al2O3-SiO2 slag system were determined according to the principle of low melting point selection. The melting and crystallization properties of B2O3 mold flux with various contents were studied experimentally by means of Brookfield rotational viscometer and DHTT-II melting crystallization temperature tester. Furthermore, the simulation of the molten slag was conducted by the molecular dynamics software. The microstructure of the mold flux was analyzed and an in-depth discussion of the relationship between the properties and the structure of the mold flux was carried out. It could be found from the results that B2O3 exerted an exceptional effect on the viscosity and transition temperature of CaO-Al2O3-SiO2 system. When the content of B2O3 was no higher than 9%, the increase of B2O3 content would result in sharp reduction in viscosity and transition temperature of the slag. Additio-nally, the growing B2O3 content in the mold flux also leaded to prolonging of the crystallization time and complete crystallization time of the mold flux. The B-O coordination structure is the most stable compared to the Al-O and Si-O coordination structures. In this system, B ions can replace Si and Al ions to form a B-O tricoordinate structure and a B-O tetracoordinate structure. Meanwhile, the structure altered from a compact framework structure to a relaxed layer structure, accompanied by a lowered slag polymerization degree and a declined viscosity.
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Published: 28 April 2019
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Fund:This work was financially supported by the National Natural Science Foundation of China (51774141), the National Natural Science Foundation Youth Fund of China (51404088), Natural Science Foundation of Hebei Province(E2015209217, E2018209195). |
About author:: Xingjuan Wang, is an associate professor at the College of Metallurgy and Energy, North Chian University of Science and Technology. In 2002, she graduated from Hebei Polytechnic University with a bachelor's degree in College of Metallurgy and Energy. In 2005, she graduated from the same school with a master's degree. And she received her Ph.D. degree in University of Science and Technology Beijing in 2013. Her research interests are technical innovation and process optimization for defect-free solidification and high efficiency continuous casting. |
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1 Hooli P O. Iron-making and Steelmaking,2002,29(4), 293. 2 Takeuchi E, Brimacombe J K. Metallurgical Transactions B, 1984, 15(3), 493. 3 Tang P, Gao J X, Wen G H. Steelmaking, 2017, 33(3), 1(in Chinese). 唐萍, 高金星, 文光华.炼钢, 2017, 33(3), 1. 4 Fu X, Wen G, Liu Q, et al. Steel Research International, 2015, 86(2), 110. 5 Omoto T, Suzuki T, Ogata H. Shinagawa Technical Report, 2007, 50, 57. 6 Hammerschmid P, Janke D. Steel Research, 1991, 62(9), 395. 7 Cai Z, Song B, Li L, et al. Metals, 2018, 8(10), 737. 8 Liu Z, Tang P, Wen G H, et al. Chinese Journal of Rare Metals, 2006, 30(4), 457(in Chinese). 刘著, 唐萍, 文光华, 等.稀有金属, 2006, 30(4), 457. 9 Yu X, Wen G H, Tang P, et al. Journal of Chongqing University, 2011, 34(1), 66(in Chinese). 于雄, 文光华, 唐萍, 等. 重庆大学学报, 2011, 34(1), 66. 10 Li J L. Study on the physics and chemistry of mold flux for high aluminum steel casting. Ph.D. Thesis, University of Science and Technology Beijing, China, 2016(in Chinese). 黎江玲. 高铝钢连铸保护渣的物理化学研究. 博士学位论文, 北京科技大学, 2016. 11 Wu T. Study on microstructure and macroproperty of mould fluxes with low-reactivity. Ph.D. Thesis, Chongqing University, China, 2017(in Chinese). 吴婷. 低反应性连铸保护渣熔体的微结构特征及宏观性能研究. 博士学位论文. 重庆大学, 2017. 12 Wang X J, Tian K, Fan Y P, et al. Materials Review B:Research Papers, 2018, 32(12), 2100(in Chinese). 王杏娟, 田阔, 樊亚鹏, 等. 材料导报:研究篇, 2018, 32(12), 2100. 13 Yu X. Fundamental research on the mold slags used for high-Al steels. Ph.D. Thesis, Chongqing University, China, 2011(in Chinese). 于雄. 高铝钢连铸结晶器保护渣的基础研究. 博士学位论文,重庆大学,2011. 14 Zhu L G, Hu B, Wang X J, et al. Materials Review A:Review Papers, 2013, 27(11), 77(in Chinese). 朱立光, 胡斌, 王杏娟, 等. 材料导报:综述篇, 2013, 27(11), 77. 15 Long X, He S P, Wang Q. Journal of Iron and Steel Research, 2018, 30(1), 21(in Chinese). 龙潇, 何生平, 王谦.钢铁研究学报, 2018, 30(1), 21. 16 Alder B J, Wainwright T E. Journal of Chemical Physics, 1957, 27(5), 1208. 17 Cui S X, Hu H Q, Xiao X G, et al. Journal of Liaocheng University(Natural Science Edition), 2005, 18(1), 30(in Chinese). 崔守鑫, 胡海泉, 肖效光, 等. 聊城大学学报(自然科学版), 2005, 18(1), 30. 18 Soules T F. Journal of Chemical Physics, 1979, 71(11), 4570. 19 Rosenthal A B, Garofalini S H. Journal of the American Ceramic Society, 2010, 70(11), 821. 20 Delaye J M, Louis-Achille V, Ghaleb D. Journal of Non-crystalline Solids, 1997, 210(2-3), 232. 21 Zhang Z T, Wen G, Tang P, et al. ISIJ International, 2008, 48(6), 739. 22 Lu B X, Chen K, Wang W L, et al. Metallurgical and Materials Tran-sactions B, 2014, 45(4), 1496. 23 Ren Z X, Jian L Z, Zhi Y W, et al. Steel Research International, 2017, 88(4),1600241. 24 Liang X P, Lu D X, Wang Y, et al. Journal of Chongqing University, 2015, 38(5), 135(in Chinese). 梁小平, 陆东旭, 王雨, 等.重庆大学学报, 2015, 38(5), 135. |
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