Comparison between the surface defects caused by Al2O3 and TiN inclusions in interstitial-free steel auto sheets

  • Rui WangEmail author
  • Yan-ping Bao
  • Zhi-jie Yan
  • Da-zhao Li
  • Yan Kang


Al2O3 and TiN inclusions in interstitial-free (IF) steel deteriorate the properties of the steel. To decrease the defects of cold-rolled sheet, it is important to clearly distinguish between the degrees of damage caused by these two inclusions on the surface quality of the steel. In this study, a nanoindenter was used to test the mechanical properties of the inclusions, and the distribution and size of the inclusions were obtained by scanning electron microscopy (SEM). It was found that when only mechanical properties are considered, TiN inclusions are more likely to cause defects than Al2O3 inclusions of the same size during the rolling process. However, Al2O3 inclusions are generally more inclined to cause defects in the rolling process than TiN inclusions because of their distribution characteristic in the thickness direction. The precipitation of Al2O3 and TiN was obtained through thermodynamical calculations. The growth laws of inclusions at different cooling rates were calculated by solidification and segregation models. The results show that the precipitation regularity is closely related to the distribution law of the inclusions in IF slabs along the thickness direction.


interstitial-free steel inclusions nanoindenter inclusion precipitation 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.



This work was financially supported by the National Natural Science Foundation of China (No. 51804279).


  1. [1]
    J.L. Guo, Y.P. Bao, and M. Wang, Cleanliness of Ti-bearing Al-killed ultra-low-carbon steel during different heating processes, Int. J. Miner. Metall. Mater., 24(2017), No. 12, p. 1370.CrossRefGoogle Scholar
  2. [2]
    X.X. Deng, L.P. Li, X.H. Wang, J.Q. Ji, C.X. Ji, and G.S. Zhu, Subsurface macro-inclusions and solidified hook character in aluminum-killed deep-drawing steel slabs, Int. J. Miner. Metall. Mater., 21(2014), No. 6, p. 531.CrossRefGoogle Scholar
  3. [3]
    R. Kuziak, H. Hartman, M. Budach, and R. Kawalla, Effect of processing parameters on precipitation reactions occurring in a Ti-bearing IF steel, Mater. Sci. Forum, 500–501(2005), p. 687.CrossRefGoogle Scholar
  4. [4]
    O. León-Garcia, R. Petrov, and L.A.I. Kestens, Void initiation at TiN precipitates in IF steels during tensile deformation, Mater. Sci. Eng. A, 527(2010), No. 16–17, p. 4202.CrossRefGoogle Scholar
  5. [5]
    Y. Hu, W.Q. Chen, C.J. Wan, F.J. Wang, and H.B. Han, Effect of deoxidation process on inclusion and fatigue performance of spring steel for automobile suspension, Metall. Mater. Trans. B, 49(2018), No. 2, p. 569.CrossRefGoogle Scholar
  6. [6]
    L.F. Zhang, C.B. Guo, W. Yang, Y. Ren, and H.T. Li, Deformability of oxide inclusions in tire cord steels, Metall. Mater. Trans. B, 49(2018), No. 2, p. 803.CrossRefGoogle Scholar
  7. [7]
    L. Yang, G.G. Cheng, S.J. Li, M. Zhao, G.P. Feng, and T. Li, A coupled model of TiN inclusion growth in GCr15SiMn during solidification in the electroslag remelting process, Int. J. Miner. Metall. Mater., 22(2015), No. 12, p. 1266.CrossRefGoogle Scholar
  8. [8]
    W.J. Ma, Y.P. Bao, L.H. Zhao, and M. Wang, Control of the precipitation of TiN inclusions in gear steels, Int. J. Miner. Metall. Mater., 21(2014), No. 3, p. 234.CrossRefGoogle Scholar
  9. [9]
    T. Miyake, M. Morishita, H. Nakata, and M. Kokita, Influence of sulphur content and molten steel flow on entrapment of bubbles to solid/liquid interface, ISIJ Int., 46(2006), No. 12, p. 1817.CrossRefGoogle Scholar
  10. [10]
    T.Y. Tsui, J. Vlassak, and W.D. Nix, Indentation plastic displacement field: Part II. The case of hard films on soft substrates, J. Mater. Res., 14(1999), No. 6, p. 2204.CrossRefGoogle Scholar
  11. [11]
    X. Li, Y.P. Bao, and M. Wang, Genetic evolution of inclusions in interstitial-free steel during the cold rolling processes, Trans. Indian Inst. Met., 71(2018), No. 5, p. 1067.CrossRefGoogle Scholar
  12. [12]
    H.L. Yu, X.H. Liu, H.Y. Bi, and L.Q. Chen, Deformation behavior of inclusions in stainless steel strips during multi-pass cold rolling, J. Mater. Process. Technol., 209(2009), No. 1, p. 455.CrossRefGoogle Scholar
  13. [13]
    I. Ohnaka, Mathematical analysis of solute redistribution during solidification with diffusion, Trans. Iron Steel Inst. Jpn., 26(1986), No. 12, p. 1045.CrossRefGoogle Scholar
  14. [14]
    H.Y. Liu, H.L. Wang, L. Li, J.Q. Zheng, Y.H. Li, and X.Y. Zeng, Investigation of Ti inclusions in wire cord steel, Ironmaking Steelmaking, 38(2011), No. 1, p. 53.CrossRefGoogle Scholar
  15. [15]
    J.H. Shang, X.J. Wang, and Y.Z. Chu, Recent development on precipitation behaviour of second-phase particles in Ti-IF steels during hot rolling, J. Iron Steel Res., 12(2000), No. 6, p. 55.Google Scholar
  16. [16]
    H. Goto, K.I. Miyazawa, K.I. Yamaguchi, S. Oglibayashi, and K. Tanaka, Effect of cooling rate on oxide precipitation during solidification of low carbon steels, ISIJ Int., 34(1994), No. 5, p. 414.CrossRefGoogle Scholar
  17. [17]
    H.J. Wu, N. Wei, Y.P. Bao, G.X. Wang, C.P. Xiao, and J.J. Liu, Effect of M-EMS on the solidification structure of a steel billet, Int. J. Miner. Metall. Mater., 18(2011), No. 2, p. 159.CrossRefGoogle Scholar

Copyright information

© University of Science and Technology Beijing and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Rui Wang
    • 1
    Email author
  • Yan-ping Bao
    • 2
  • Zhi-jie Yan
    • 1
  • Da-zhao Li
    • 1
  • Yan Kang
    • 1
  1. 1.School of Materials Science and EngineeringNorth University of ChinaTaiyuanChina
  2. 2.State Key Laboratory of Advanced MetallurgyUniversity of Science and Technology BeijingBeijingChina

Personalised recommendations