Abstract：In order to develop better refractories to improve the purity of saw wire steel, the effects of MgO and MgO-CaO refractories on inclusions in the 95Cr saw wire steel were studied using MoSi2 furnace in the present experiment. The results indicated that both MgO and MgO-CaO crucibles can control the composition of all of the elements in the steel within the target range and the drop point of inclusion composition within the target low melting point zone. However, compared with the MgO crucible, the MgO-CaO crucible has a better effect in purifying the molten steel, mainly in two aspects. On the one hand, the contents of P, S, [Al]s and T[O] in steel are lower. Especially, the w([S]) can be reduced to 0.000 6%, the w([Al]s) to 0.000 3% and the w(T[O]) to 0.000 5%. On the other hand, the number of inclusions in steel is less, the size is smaller, and the content of Al2O3 in composite inclusions is lower. Specifically, the proportion of inclusions with an effective diameter of less than 2 μm in steel is 91% after smelting with MgO-CaO crucible, while that of the steel smelted with MgO crucible is only 78%. Moreover, after the MgO-CaO crucible smelting, the mass percent of Al2O3 in complex inclusions in steel is almost less than 10.0%. This is mainly because both MgO and CaO in MgO-CaO refractories can remove P, and CaO also removes S and Al2O3 inclusions in the steel.
[1] LI Y, CHEN C Y, JIANG Z H, et al. Application of alkali oxides in LF refining slag for enhancing inclusion removal in C96V saw wire steel[J]. ISIJ International, 2018, 58(7): 1232. [2] CHEN C Y, JIANG Z H, LI Y, et al. Effect of Rb2O on inclusion removal in C96V saw wire steels using low-basicity LF refining slag[J]. ISIJ International, 2018, 58(11):2032. [3] CHEN C Y, JIANG Z H, LI Y, et al. Effect of Na2O and Rb2O on inclusion removal in C96V saw wire steels using low-basicity LF (Ladle Furnace) refining slags[J]. Metals, 2018, 8(9): 691. [4] JIANG Z H, CHEN C Y, LI Y, et al. Effect of K2O on inclusion removal in C96V saw wire steels using LF refining slags [C]// 7th International Congress on Science and Technology of Steelmaking. Venice: Italian Association for Metallurgy, 2018: 1029. [5] 孙萌. 稀土元素Ce对切割钢丝用钢C104Cr夹杂物、组织与机械性能的影响研究[D]. 沈阳: 东北大学, 2018. (SUN-Meng. Effect of Cerium on Inclusions, Microstructure and Mechanical Properties of C104Cr Saw Wire Steel [D]. Shenyang: Northeastern University, 2018.) [6] LI Y, SUN M, JIANG Z H, et al. Inclusion modification in C104Cr saw wire steel with different cerium content[J]. Metals, 2019, 9(1): 54. [7] 王昆鹏, 姜敏, 赵昊乾, 等. 切割丝用盘条非金属夹杂物对比分析[J]. 钢铁, 2016, 51(1): 33. (WANG Kun-peng, JIANG Min, ZHAO Hao-qian, et al. Contrast on non-metallic inclusions control in wire rods for saw wire[J]. Iron and Steel, 2016, 51 (1): 33.) [8] 王昆鹏, 姜敏, 赵昊乾, 等. 帘线钢生产过程中氧化物夹杂的演变规律[J]. 钢铁, 2016, 51(4): 31. (WANG Kun-peng, JIANG Min, ZHAO Hao-qian, et al. Characterization on changes of oxide inclusions in production process of tire cord steel[J]. Iron and Steel, 2016, 51 (4): 31.) [9] 王昆鹏, 姜敏, 王新华, 等. 钢帘线和切割丝用钢夹杂物控制技术的进展[J]. 特殊钢, 2016, 37(2): 26. (WANG Kun-peng, JIANG Min, WANG Xin-hua, et al. Progress of control technology of inclusions in steel for tyre cord and saw wire[J]. Special Steel, 2016, 37(2), 26.) [10] 王昆鹏, 王新华, 姜敏, 等. 切割丝生产过程夹杂物特征研究[J]. 炼钢, 2016, 32(4): 17. (WANG Kun-peng, WANG Xin-hua, JIANG Min, et al. Study on non-metallic inclusions in high quality saw wires[J]. Steelmaking, 2016, 32(4): 17.) [11] WANG K P, JIANG M, WANG X H, et al. Study on formation mechanism of CaO-SiO2-based inclusions in saw wire steel[J]. Metallurgical and Materials Transactions B, 2017, 48(6): 2961. [12] WANG K P, JIANG M, WANG X H, et al. Formation mechanism of CaO-SiO2-Al2O3-(MgO) inclusions in Si-Mn-killed steel with limited aluminum content during the low basicity slag refining[J]. Metallurgical and Materials Transactions B, 2016, 47(1): 282. [13] WANG K P, JIANG M, WANG X H, et al. Formation mechanism of SiO2-type inclusions in Si-Mn-killed steel wires containing limited aluminum content[J]. Metallurgical and Materials Transactions B, 2015, 46(5): 2198. [14] 张永启. 镁处理对硅锰脱氧钢中夹杂物形态控制的研究[D]. 沈阳, 东北大学 2014. (ZHANG Yong-qi. The Study on Morphological Control of Inclusions Using Mg Treatment in Si-Mn Deoxidized Steel[D]. Shenyang: Northeastern University, 2014.) [15] 陶绍平, 钟香崇. MgO基和Al2O3基耐火材料对钢中夹杂物的影响[J]. 钢铁, 2007, 42(5): 33. (TAO Shao-ping, ZHONG Xiang-chong. Influence of MgO-based and Al2O3-based refractories on inclusions in molten steel[J]. Iron and Steel, 2007, 42(5): 33) [16] 何平显, 汪庆丰, 陆晓明, 等. 含Al2O3耐材对帘线钢增铝的影响[C]//全国耐火材料青年学术报告会, 西安:中国金属学会, 2006: 255. (HE Ping-xian, WANG Qing-feng, LU Xiao-ming, et al. Effect of A12O3 refractory on aluminizing of cord steel[C]//The 10th National Youth Conference on refractories, Xi′an:The Chinese Society for Metals, 2006:255.) [17] Iemura K, Ichihashi K, Kawami A, et al. Steelmaking process for high-carbon tyre cord steel[C]//3rd International Conference on Clean Steel. Baraton: [s.n], 1986: 160. [18] Ueno A, Kimura K, Kawami K, Improvement in steelmaking process for clean steel of wire rods[C]//Steelmaking Conference Proceedings. New York:[s.n], 1987: 389. [19] 赵昊乾, 陈伟庆. 坩埚材质及顶渣成分对帘线钢夹杂物成分的影响[J]. 钢铁研究学报, 2012, 24(3): 12. (ZHAO Hao-qian, CHEN Wei-qing. Effect of crucible material and top slag composition on the inclusion composition of tire cord steel[J]. Journal of Iron and Steel Research, 2012, 24(3): 12.) [20] Mantovani M C, Moraes L R, Leandro da Silva R, et al. Interaction between molten steel and different kinds of MgO based tundish linings[J]. Ironmaking and Steelmaking, 2013, 40(5): 319. [21] 陈家祥. 炼钢常用图表数据手册[M].北京: 冶金工业出版社, 2010. (CHEN Jia-xiang. Data Manual of Charts and Charts Used in Steelmaking[M]. Beijing: Metallurgical Industry Press, 2010.) [22] 汪大洲. 钢铁生产中的脱磷[M] 北京: 冶金工业出版社, 1986. (WANG Da-zhou. Dephosphorization in Iron and Steel Production[M]. Beijing: Metallurgical Industry Press, 1986.) [23] 李楠, 匡加才. 碱性耐火材料脱磷作用的研究[J]. 耐火材料, 2000, 34(5): 249. (LI Nan, KUANG Jia-cai. Study on dephosphorization of alkaline refractories[J] Refractories, 2000, 34(5): 249.) [24] Ye Guo-zhu, Jönsson Pär, Lund Thore. Thermodynamics and kinetics of the modification of Al2O3 inclusions[J]. ISIJ International, 1996, 36: S105. [25] Goto H, Miyazawa K I, Kadoya T. Effect of the composition of oxide on the reaction between oxide and sulfur during solidification of steels[J]. ISIJ International, 1995, 35(12):1477. [26] Nagata K, Tanabe J, Goto K S. Activities of calcium oxide in Cao based inclusions measured by galvanic cells[C]//Proceedings of The Sixth International Iron and Steel Congress. Nagoya: Iron and Steel Institute of Japan, 1990: 217.
2020, Vol. 55 
