Abstract
This paper compares inclusions in high nitrogen steel before and after ESR process, analyzes the influence of slag systems and total oxygen content in consumable ingots. The total oxygen content is reduced apparently during ESR process, which indicates good effects on removal of inclusions. In the experiment, it shows that different slag systems will affect the result of inclusions removal significantly; proper w(CaO/Al2O3) will reduce the level of inclusions and total oxygen content in ESR ingots. In ESR process, the type and chemical composition of inclusions have no difference when oxygen content in consumable ingots is different, which means O content in consumable ingots have no direct relationship with cleanliness of ESR ingots. In typical inclusions, w(MnO)/w(MnO+Al2O3)≈0.23~0.32. The total oxygen content of ESR ingots keeps between 20~30ppm when the oxygen contents in consumable ingots are diverse from 40 to 100ppm. Meanwhile, this paper studies desulfurization process of high nitrogen steel in ESR, analyzes the influence of slag systems a nd remelting rates on desulfurization efficiency. The results indicate that the average size and quant ity of sulfide inclusion decrease after ESR process. The typical inclusion after ESR process is MnS+Al2O3. Slag system with proper CaO content has higher sulfur partition ratio, which leads to better desulfurization effect. The desulfurization rate changes greatly with different remelting rates, which indicates the kinetic parameter has more influence in desulfurization. The reason of this phenomenon is that the process of desulfurization can be considered as a non-equilibrium reaction, which differs with thermodynamic equilibrium. In kinetic study, it is founded that the desulfurization efficiency increases with higher remelting area, sulfur partition and lower remelting rate, which is different from experiment. The desulfurization efficiency decreases firstly and then recovers when remelting rate drops. The enrichment of sulfide in slag results in resulfurization in steel, which leads to lower desulfurization efficiency.
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References
Shigeki Azuma, Hideaki Miyuki and Takeo Kudo, “Effect of Alloying Nitrogen on Crevice Corrosion of Austenitic Stainless Steel”, ISIJ International, 36(7)(1996),793–798.
Li Guang-qiang, Dong Ting-liang, “Progresses on Application and Fundamental of High Nitrogen Steels”, China Meta llurgy, 17(7)(2007),5–11.
Seung Chul Baik et al, “Effects of Nitrogen on the M echanical Properties of Cold Rolled Trip -aided Steel Sheets”, ISIJ International, 46(4)(2006),599–605.
Yi Bang-wang, Hu Yan and Lang Wen-yun, “Effect of Content on Mechanical Properties, Magnetic of Cr18Mn18N Conductivity and M icrostructure”, Iron and Steel, 33(3)(1998),43–45.
Baokuan Li, Fang Wang and Fumitaka Tsukihashi, “Current, Magnetic Field and Joule Heating in Electroslag Remelting Processes”, ISIJ International, 52(7)(2012),1289–1295.
V. Weber et al, “A Comprehensive Model of the Electroslag Remelting Processes: Description and Validation”, Metallurgical and Materials Transactions B, 40(B)(2009),271–280.
Geng Xin et al, “Control of non-metallic Inclusion in ESR Process”, Iron and Steel, 44(12)(2009),42–45.
Li Zheng-bang, Zhou Wei-hui and Wang Qing-he. “The Influence of Composition of Inclusions in Consumable Electrode on the Effect of Electroslag Remalting”, Iron and Steel, 18(5)(1983),13–20.
Shi Chengbin et al, “Assessment of Oxygen Control and its Effect on Inclusion Characteristics during Electroslag Remelting of Die Steel”, Steel Research International, 83(5)(2012),472–486.
Yang Hai-sen et al, “Study on Oxygen Change during Electroslag Remelting”, Journal of Materials and Metallurgy, 10(2011),44–49.
Jun Seok Park and Joo Hyun Park, “Effect of slag composition on the concentration of Al2O3 in the inclusions in Si-Mn killed steel”, Metallurgical and materials transactions B, 44(2013),1–8.
Zhou Deguang et al, “Control and Behavior of Oxygen during Electroslag Remelting of Bearing Steel”, Iron and Steel, 29(7)(1994),13–17.
Wang F, Chen X C and Shi C B, “The Kinetics Model of PESR Process on Desulfurization” (Paper presented at the Academic conference of Electroslag metallurgy 2012, Hang Zhou,2012), 250.
Li S Q et al, “Kinetic Model of Desulfurization of Ultra-low S Steel”, Journal of University of Science and Technology Beijing, 26(3)(2004),245–249.
Medina S F, Andres M P, “Electrical Field in the Resistivity Medium (Slag) of the ESR Process: Influence on Ingot Production and Quality”, Ironmaking and Steelmaking, 14(3)(1987),110–121.
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Xuwei, T., Rong, Z. (2014). Study of Cleanliness of High Nitrogen Steel in ESR. In: Energy Materials 2014. Springer, Cham. https://doi.org/10.1007/978-3-319-48765-6_39
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DOI: https://doi.org/10.1007/978-3-319-48765-6_39
Publisher Name: Springer, Cham
Print ISBN: 978-3-319-48598-0
Online ISBN: 978-3-319-48765-6
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