Effect of MgO on microstructure of CaO-Al2O3 based quaternary system mold fluxes
LIU Ke1,2, HAN Yi-hua1,2, YANG Fan1,2, ZHU Li-guang2,3
1. College of Metallurgy and Energy, North China University of Science and Technology, Tangshan 063210, Hebei, China; 2. Hebei Engineering Research Center of High Quality Steel Continuous Casting, Tangshan 063000, Hebei, China; 3. School of Materials Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, Hebei, China
Abstract:In order to study the influence of MgO on the microstructure of CaO-Al2O3-B2O3-MgO quaternary slag system,the slag network structure model of CaO-Al2O3-B2O3-MgO-based quaternary slag system was constructed by Scigress molecular dynamics software. The results demonstrated that high-coordinated Al and tri-coordinate oxygen appear in the molten slag to compensate for [AlO4]5- tetrahedral negative charge excess;Boron as the network forming body has the strongest binding ability with O,and its coordination structure exists as Tri-coordinated trigonal and tetra-coordinated tetrahedrons;MgO acts as a network modifiers to compensate for charge and depolymerization networks. With the increasing of MgO content,the stability of the Al—O network structure enhanced,while the degree of polymerization of the melt and the complexity of the network structure decreased.
刘克, 韩毅华, 杨帆, 朱立光. MgO对CaO-Al2O3基四元系保护渣熔渣微结构的影响[J]. 钢铁, 2020, 55(5): 52-58.
LIU Ke, HAN Yi-hua, YANG Fan, ZHU Li-guang. Effect of MgO on microstructure of CaO-Al2O3 based quaternary system mold fluxes. Iron and Steel, 2020, 55(5): 52-58.
[1] 张磊,翟冰钰,王万林. 高铝钢连铸用非反应型保护渣的研究进展[J]. 江西冶金,2019,39(2):7. (ZHANG Lei,ZHAI Bing-yu,WANG Wan-lin. Research progress of non-reactive mold fluxes for continuous casting of high alumina steel[J]. Jiangxi Metallurgy,2019,39(2):7.) [2] 刘春秀,杜辰伟,兰鹏,等.连铸保护渣与氧化铝的交互作用研究现状[J]. 中国冶金,2015,25(9):15.(LIU Chun-xiu,DU Chen-wei,LAN Peng,et al. Research status of interaction between continuous casting slag and alumina[J].China Metallurgy,2015,25(9):15.) [3] 何生平,曾建华,汪灿荣,等. 连铸含铝钢中Al2O3夹杂物形态控制探讨[J]. 连铸,2011(s1):63. (HE Sheng-ping,ZENG Jian-hua,WANG Can-rong,et al. Discussion on morphology control of Al2O3 inclusions in continuous casting aluminum-containing steel[J]. Continuous Casting,2011(s1):63.) [4] Wang W,Blazek K,Cramb A. A study of the crystallization behavior of a new mold flux used in the casting of transformation-induced-plasticity steels[J]. Metallurgical and Materials Transactions B,2008,39(1):66. [5] 王哲,唐萍,米晓希,等. CaF2对CaO-SiO2-Al2O3渣系保护渣结晶行为的影响[J]. 钢铁,2018,53(7):38. (WANG Zhe,TANG Ping,MI Xiao-xi,et al. Effect of w((CaF2)) on crystallization properties of CaO-SiO2-Al2O3 based mold fluxes[J]. Iron and Steel,2018,53(7):38.) [6] WU T,QIAN W,HE S,et al. Study on properties of alumina-based mould fluxes for high-Al steel slab casting[J]. Steel Research International,2012,83(12):1194. [7] QIANG W,MIN S,QIU S,et al. Study on mold slag with high Al2O3 content for high aluminum steel[J]. Metallurgical and Materials Transactions B,2014,45(2):540. [8] Kang Y,Morita K. Thermal conductivity of the CaO-Al2O3-SiO2 system[J]. ISIJ International,2006,46(3):420. [9] 赵谦,祖群,齐亮,等. 分子动力学模拟预测氧化钠含量对二元钠硅酸盐玻璃弹性模量的影响[J].硅酸盐学报,2018,46(11):1558. (ZHAO Qian,ZU Qun,QI Liang,et al.Molecular dynamics simulation predicts the effect of sodium oxide content on elastic modulus of binary sodium silicate glass[J]. Acta Silicata Sinica,2018,46(11):1558.) [10] 贾天有. 关于炉渣熔体密度的计算[J]. 科技译丛,1994(1):54.(JIA Tian-you.Calculation of slag melt density[J]. Translations of Science and Technology,1994(1):54.) [11] Belashchenko D K,Gopengauz I E,Grytsenko A B,et al. Computational study on structure of non-crystalline oxides 2MeO-SiO2(Me=Mg,Ca,Sr,Ba,Fe)[J]. ISIJ International,1992,32(9):990. [12] Mead R N,Mountjoy G. A molecular dynamics study of the atomic structure of (CaO)x(SiO2)1-x glasses[J]. Journal of Physical Chemistry B,2006,110(29):14273. [13] Thomas B W M,Mead R N,Mountjoy G. A molecular dynamics study of the atomic structure of (CaO)x(Al2O3)1-x glass with x=0.625 close to the eutectic[J]. Journal of Physics Condensed Matter,2006,18(18):4697. [14] Mei Q,Benmore C J,Siewenie J,et al. Diffraction study of calcium aluminate glasses and melts:I. High energy X-ray and neutron diffraction on glasses around the eutectic composition[J]. Journal of Physics Condensed Matter,2008,20(24):266. [15] Hannon A C,Parker J M. The structure of aluminate glasses by neutron diffraction[J]. Journal of Non-Crystalline Solids,2000,274(1):102. [16] 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[D]. 重庆:重庆大学,2017.(WU Ting. Microstructure Characteristics and Macroscopic Properties of Low Reactivity Continuous Casting Flux Slag[D]. Chongqing:Chongqing University,2017.) [17] 高金星. 含Al2O3和CaF2连铸结晶器保护渣成分、结构和性能的基础研究[D]. 重庆:重庆大学,2016.(GAO Jin-xing. Basic Research on Composition,Structure and Properties of Mold Flux for Al2O3 and CaF2 Continuous Casting Molds[D]. Chongqing:Chongqing University,2016.) [18] ZHENG K,ZHANG Z T,YANG F H,et al. Investigation of the structural properties of calcium aluminosilicate slags with varying Al2O3/SiO2ratios using molecular dynamics[J]. ISIJ International,2012,52(3):342.