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Crystallization Characteristics and In-Mold Performance of Electroslag Remelting-Type TiO2-Bearing Slag

  • Dingli Zheng
  • Jing LiEmail author
  • Chengbin ShiEmail author
  • Jiantao Ju
Article
  • 38 Downloads

Abstract

The non-isothermal crystallization characteristics of the electroslag remelting (ESR)-type TiO2-bearing slag were studied. The effect of crystallization characteristics of the slag on the in-mold performance was verified by ESR pilot trials operating in a static mode. The results showed that increasing TiO2 content decreased the crystallization temperature and liquidus temperature of the slag and suppressed the crystallization tendency of the slag. There is no change in the types of the crystalline phases in the slag with different TiO2 contents during cooling, i.e., 11CaO·7Al2O3·CaF2, CaTiO3, and CaF2. The sequence of crystal precipitation during cooling was 11CaO·7Al2O3·CaF2 to CaTiO3, and then CaF2 with increasing TiO2 content from 4.2 to 12.6 mass pct. With adding 16.8 mass pct TiO2 in the slag, the precipitation of 11CaO·7Al2O3·CaF2 and CaTiO3 took place simultaneously, followed by CaF2. With the increase in the TiO2 content from 4.2 to 16.8 mass pct in the slag, the dominant crystalline phase changed from 11CaO·7Al2O3·CaF2 to CaTiO3. The morphology of 11CaO·7Al2O3·CaF2 and CaTiO3 changed from faceted and bonelike to elliptically faceted and blocky, respectively. The morphology of CaF2 were spherical in all cases, irrespective of TiO2 contents in the slag. The decrease in the crystallization tendency of the slag with increasing TiO2 contents was attributed to the decrease in the activity of CaO in the slag. The increasing of TiO2 content in the slag are favorable for providing thin slag skin and stable heat flux across the slag skin, which improved the surface quality of the as-cast ESR ingot as demonstrated by ESR pilot trials operating in a static mode.

Notes

Acknowledgments

The authors are sincerely grateful to Professor Jung-wook Cho, Pohang University of Science and Technology, for his help in using the FactSage software. The financial support by the National Natural Science Foundation of China (Grant Nos. 51774225, 51874030, and 51874026) and the Fundamental Research Funds for the Central Universities (Grant No. FRF-TP-18-004A3) is greatly acknowledged.

References

  1. 1.
    1.M. Eissa and A. Ei‐Mohammad: Steel. Res., 1998, vol. 69, pp. 413–17.CrossRefGoogle Scholar
  2. 2.
    2.C.B. Shi, H. Wang, and J. Li: Metall. Mater. Trans. B, 2018, vol. 49B, pp. 1675–89.CrossRefGoogle Scholar
  3. 3.
    3.A. Ahmed and A. Fathy: Ironmaking Steelmaking, 2008, vol. 35, pp. 458–64.CrossRefGoogle Scholar
  4. 4.
    4.C.B. Shi, W.T. Yu, H. Wang, J. Li, and M. Jiang: Metall. Mater. Trans. B, 2017, vol. 48B, pp. 146–61.CrossRefGoogle Scholar
  5. 5.
    5.C.B. Shi, J. Li, J.W. Cho, F. Jiang, and I.H. Jung: Metall. Mater. Trans. B, 2015, vol. 46B, pp. 2110–20.CrossRefGoogle Scholar
  6. 6.
    6.Z.X. Xue, Y.X. Zheng, F. Jiang, Y.Q. Du, B.S. Guo, P. Lin, and C.B. Shi: Special Steel, 2016, vol. 37, pp. 37–40 (in Chinese).Google Scholar
  7. 7.
    7.X.C. Lu: Foundry, 2002, vol. 51, pp. 378–80 (in Chinese).Google Scholar
  8. 8.
    8.H.Y. Zhao: Special Steel, 2006, vol. 27, pp. 61–62 (in Chinese).Google Scholar
  9. 9.
    9.G. Pateisky, H. Biele, and H.J. Fleischer: J. Vac. Sci. Technol., 1972, vol. 9, pp. 1318–21.CrossRefGoogle Scholar
  10. 10.
    10.C.B. Shi, M.D. Seo, J.W. Cho, and S.H. Kim: Metall. Mater. Trans. B, 2014, vol. 45B, pp. 1081–97.CrossRefGoogle Scholar
  11. 11.
    X.M. Li, S.J. Wang, J.X. Zhao, Y.R. Cui, and Y.M. Chen, Adv. Mater. Res., 2011, vols. 239–242, pp. 1960–63.Google Scholar
  12. 12.
    12.X. Li, X. Geng, Z.H. Jiang, H.B. Li, F.H. Xu, and L.X. Wang: Iron Steel, 2015, vol. 50, pp. 41–46 (in Chinese).CrossRefGoogle Scholar
  13. 13.
    13.C.B. Shi, J.W. Cho, D.L. Zheng, and J. Li: Int. J. Miner. Metall. Mater., 2016, vol. 23, pp. 627–36.CrossRefGoogle Scholar
  14. 14.
    14.J.L. Li, Q.F. Shu, X.M. Hou, and K.C. Chou: ISIJ Int., 2015, vol. 55, pp. 830–36.CrossRefGoogle Scholar
  15. 15.
    D.D.R. Silva, A.C.F. Vilela, N.C. Heck, H.P. Heller, and O. Volkova: Steel. Res. Int., 2018,  https://doi.org/10.1002/srin.201700246.Google Scholar
  16. 16.
    16.Z.Q. Hao, W.Q. Chen, C. Lippold, and H.X. Mao: Chin. J. Process Eng., 2009, vol. 9, pp. 514–18 (in Chinese).Google Scholar
  17. 17.
    17.J.A. Bothma and P.C. Pistorius: Ironmaking Steelmaking, 2007, vol. 34, pp. 513–20.CrossRefGoogle Scholar
  18. 18.
    M.L. Hu, R.R. Wei, F.F Yin, L. Liu, and Q.Y. Deng: JOM, 2016, vol. 68, pp. 2502–10.Google Scholar
  19. 19.
    19.M.D. Seo, J.W. Cho, and S.H. Kim: Metall. Mater. Trans. B, 2014, vol. 45B, pp. 1874–86.CrossRefGoogle Scholar
  20. 20.
    20.M.D. Seo, C.B. Shi, J.Y. Baek, J.W. Cho, and S.H. Kim: Metall. Mater. Trans. B, 2015, vol. 46B, pp. 2374–83.CrossRefGoogle Scholar
  21. 21.
    21.L.J. Zhou, W.L. Wang, F.J. Ma, J. Li, J. Wei, H. Matsuura, and F. Tsukihashi: Metall. Mater. Trans. B, 2012, vol. 43B, pp. 354–62.CrossRefGoogle Scholar
  22. 22.
    22.L.S. Li, X.R. Wu, L. Yu, and Y.C. Dong: Ironmaking Steelmaking, 2008, vol. 35, pp. 367–70.CrossRefGoogle Scholar
  23. 23.
    23.Z.J. Wang, Y.Q. Sun, S. Sridrar, M. Zhang, and Z.T. Zhang: Metall. Mater. Trans. B, 2017, vol. 48B, pp. 527–37.CrossRefGoogle Scholar
  24. 24.
    24.J. Li, Z.T. Zhang, L.L. Liu, W.L. Wang, and X.D. Wang: ISIJ Int., 2013, vol. 53, pp. 1696–1703.CrossRefGoogle Scholar
  25. 25.
    25.Z.H. Jiang and X. Geng: Adv. Mater. Res., 2010, vols. 146–147, pp. 670–73.CrossRefGoogle Scholar
  26. 26.
    26.J. Guo, M.D. Seo, C.B. Shi, J.W. Cho, and S.H. Kim: Metall. Mater. Trans. B, 2016, vol. 47B, pp. 2211–21.CrossRefGoogle Scholar
  27. 27.
    M. Asanishi, T. Takaki, and Y. Tomita: AES-ATEMA Int. Conf. Ser., 2007, pp. 195–203.Google Scholar
  28. 28.
    28.L. Zhao, D.G. Jin, J.J. Gao, Z.H. Zhou, and X.H. Liu: Heavy Casting Forging, 1997, vol. 3, pp. 22–27 (in Chinese).Google Scholar
  29. 29.
    29.A. Mitchell and M. Etienne: Trans. TMS-AIME, 1968, vol. 242, pp. 1462–64.Google Scholar
  30. 30.
    30.M. Bell and A. Mitchell: J. Iron Steel Inst., 1971, vol. 209, pp. 658–70.Google Scholar

Copyright information

© The Minerals, Metals & Materials Society and ASM International 2019

Authors and Affiliations

  1. 1.State Key Laboratory of Advanced MetallurgyUniversity of Science and Technology Beijing (USTB)BeijingChina
  2. 2.School of Metallurgical EngineeringXi’an University of Architecture and TechnologyXi’anChina

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