Advertisement

Metallurgical and Materials Transactions B

, Volume 48, Issue 5, pp 2293–2303 | Cite as

Study on the Microstructure and Liquid Phase Formation in a Semisolid Gray Cast Iron

  • Davi Munhoz Benati
  • Kazuhiro Ito
  • Kazuyuki Kohama
  • Hajime Yamamoto
  • Eugenio José ZoquiEmail author
Article

Abstract

The development of high-quality semisolid raw materials requires an understanding of the phase transformations that occur as the material is heated up to the semisolid state, i.e., its melting behavior. The microstructure of the material plays a very important role during semisolid processing as it determines the flow behavior of the material when it is formed, making a thorough understanding of the microstructural evolution essential. In this study, the phase transformations and microstructural evolution in Fe2.5C1.5Si gray cast iron specially designed for thixoforming processes as it was heated to the semisolid state were observed using in situ high-temperature confocal laser scanning microscopy. At room temperature, the alloy has a matrix of pearlite and ferrite with fine interdendritic type D flake graphite. During heating, the main transformations observed were graphite precipitation inside the grains and at the austenite grain boundaries; graphite flakes and graphite precipitates growing and becoming coarser with the increasing temperature; and the beginning of melting at around 1413 K to 1423 K (1140 °C to 1150 °C). Melting begins with the eutectic phase (i.e., the carbon-rich phase) and continues with the primary phase (primary austenite), which is consumed as the temperature increases. Melting of the eutectic phase composed by coarsened interdendritic graphite flakes produced a semi-continuous liquid network homogeneously surrounding and wetting the dendrites of the solid phase, causing grains to detach from each other and producing the intended solid globules immersed in liquid.

Notes

Acknowledgments

This study was supported by São Paulo Research FoundationFAPESP under Grant Numbers 2011/19997-0 and 2015/06965-3. The authors would like to thank IMBIL Industry and Maintenance of Pumps ITA Ltda. for producing the cast iron and the Joining and Welding Research Institute, Osaka University, and the School of Mechanical Engineering, University of CampinasUNICAMP, for providing the necessary facilities.

Supplementary material

Supplementary material 1 (MP4 22960 kb)

References

  1. 1.
    [1] D.B. Spencer, R. Mehrabian and M.C. Flemings: Metall. Trans., 1972, vol. 3, pp. 1925–32. doi: 10.1007/BF02642580 CrossRefGoogle Scholar
  2. 2.
    [2] H.V. Atkinson: Prog. Mater. Sci., 2005, vol. 50, pp. 341–412. doi:  10.1016/j.pmatsci.2004.04.003 CrossRefGoogle Scholar
  3. 3.
    [3] M.C. Flemings: Metall. Trans. B, 1991, vol. 22, pp. 269–93. doi:  10.1007/BF02661090 CrossRefGoogle Scholar
  4. 4.
    [4] S. Zabler, A. Ershov, A. Rack, F. Garcia-Moreno, T. Baumbach and J. Banhart: Acta Mater., 2013, vol. 61, pp. 1244–53. doi:  10.1016/j.actamat.2012.10.047 CrossRefGoogle Scholar
  5. 5.
    [5] B. Cai, S. Karagadde, L. Yuan, T.J. Marrow, T. Connolley and P.D. Lee: Acta Mater., 2014, vol. 76, pp. 371–80. doi:  10.1016/j.actamat.2014.05.035 CrossRefGoogle Scholar
  6. 6.
    [6] T. Werz, M. Baumann, U. Wolfram and C.E. Krill III: Mater. Charact., 2014, vol. 90, pp. 185–95. doi:  10.1016/j.matchar.2014.01.022 CrossRefGoogle Scholar
  7. 7.
    [7] K. Du, Q. Zhu, D. Li and F. Zhang: Mater. Charact., 2015, vol. 106, pp. 134–40. doi:  10.1016/j.matchar.2015.05.035 CrossRefGoogle Scholar
  8. 8.
    [8] D. Phelan, N. Stanford and R. Dippenaar: Mater. Sci. Eng. A, 2005, vol. 407, pp. 127–34. doi:  10.1016/j.msea.2005.07.015 CrossRefGoogle Scholar
  9. 9.
    [9] D. Zhang, H. Terasaki and Y. Komizo: Acta Mater., 2010, vol. 58, pp. 1369–78. doi:  10.1016/j.actamat.2009.10.043 CrossRefGoogle Scholar
  10. 10.
    [10] M.M. Attallah, H. Terasaki, R.J. Moat, S.E. Bray, Y. Komizo and M. Preuss: Mater. Charact., 2011, vol. 62, pp. 760–67. doi:  10.1016/j.matchar.2011.05.001 CrossRefGoogle Scholar
  11. 11.
    Y. Komizo and H. Terasaki (2010) In situ study of phase transformation in steel during welding. In: T. Kannengiesser, S.S. Babu, Y. Komizo and A.J. Ramirez (Eds.), In situ studies with photons, neutrons and electrons scattering. Springer, Berlin, pp. 1–11. doi:  10.1007/978-3-642-14794-4_1 Google Scholar
  12. 12.
    [12] I. Sohn and R. Dippenaar: Metall. Mater. Trans. B, 2016, vol. 47, pp. 2083–94. doi:  10.1007/s11663-016-0675-0 CrossRefGoogle Scholar
  13. 13.
    [13] G.C. Gu, R. Pesci, L. Langlois, E. Becker, R. Bigot and M.X. Guo: Acta Mater., 2014, vol. 66, pp. 118–31. doi:  10.1016/j.actamat.2013.11.075 CrossRefGoogle Scholar
  14. 14.
    [14] X.G. Hu, Q. Zhu, H.X. Lu, F. Zhang, D.Q. Li and S.P. Midson: J. Alloy. Compd., 2015, vol. 649, pp. 204–10. doi:  10.1016/j.jallcom.2015.07.121 CrossRefGoogle Scholar
  15. 15.
    S.P Midson: Solid State Phenom., 2015, vol. 217-218, pp. 487–95. doi:  10.4028/www.scientific.net/SSP.217-218.487 Google Scholar
  16. 16.
    S.P. Midson: in Comprehensive Materials Processing, S. Hashimi, ed., Elsevier, Oxford, 2014, vol. 5, pp. 259–74. doi: 10.1016/B978-0-08-096532-1.00517-3
  17. 17.
    [17] M. Tsuchiya, H. Ueno and I. Takagi: JSAE Rev., 2003, vol. 24, pp. 205–14. doi:  10.1016/S0389-4304(03)00013-4 CrossRefGoogle Scholar
  18. 18.
    [18] F. Pahlevani and M. Nili-Ahmadabadi: Int. J. Cast. Metal. Res., 2004, vol. 17, pp. 157–61. doi:  10.1179/136404604225020560 CrossRefGoogle Scholar
  19. 19.
    [19] M. Ramadan, M. Takita and H. Nomura: Mater. Sci. Eng. A, 2006, vol. 417, pp. 166–73. doi:  10.1016/j.msea.2005.10.054 CrossRefGoogle Scholar
  20. 20.
    [20] M. Ramadan, N. El-Bagoury, N. Fathy, M.A. Waly and A.A. Nofal: J. Mater. Sci., 2011, vol. 46, pp. 4013–19. doi:  10.1007/s10853-011-5329-7 CrossRefGoogle Scholar
  21. 21.
    [21] B. Abbasi-Khazaei and S. Ghaderi: J. Mater. Sci. Technol., 2012, vol. 28, pp. 946–50. doi:  10.1016/S1005-0302(12)60156-X CrossRefGoogle Scholar
  22. 22.
    [22] J. Cui, H. Zhang, L. Chen, H. Li and W. Tong: Acta Metall. Sin., 2014, vol. 27, pp. 476–82. doi:  10.1007/s40195-014-0067-x CrossRefGoogle Scholar
  23. 23.
    [23] A.S. Roca, H.D.C. Fals, J.A. Pedron and E.J. Zoqui: J. Mater. Process. Technol., 2012, vol. 212, pp. 1225–35. doi:  10.1016/j.jmatprotec.2012.01.012 CrossRefGoogle Scholar
  24. 24.
    [24] R.L. Nadal, A.S. Roca, H.D.C Fals and E.J. Zoqui: J. Mater. Process. Technol., 2015, vol. 226, pp. 146–56. doi:  10.1016/j.jmatprotec.2015.07.015 CrossRefGoogle Scholar
  25. 25.
    [25] A.M. Camacho, H.V. Atkinson, P. Kapranos and B.B. Argent: Acta Mater., 2003, vol. 51, pp. 2319–30. doi:  10.1016/S1359-6454(03)00040-5 CrossRefGoogle Scholar
  26. 26.
    ASTM A247-16a: Standard test method for evaluating the microstructure of graphite in iron castings, ASTM International, West Conshohocken, PA, 2016. Doi: 10.1520/A0247-16A
  27. 27.
    ASTM E112-13: Standard test methods for determining average grain size, ASTM International, West Conshohocken, PA, 2013. doi: 10.1520/E0112
  28. 28.
    [28] G.L Rivera, R.E. Boeri and J.A. Sikora: Scr. Mater., 2004, vol. 50, pp. 331–35. doi:  10.1016/j.scriptamat.2003.10.019 CrossRefGoogle Scholar
  29. 29.
    D.M. Stefanescu: in Properties and Selection: Irons, Steels and High Performance Alloys, ASM Handbook, ASM International, 1990, vol. 1, pp. 3–11. ISBN: 978-0-87170-377-4Google Scholar
  30. 30.
    [30] W. Xue and Y. Li: J. Alloy. Compd., 2016, vol. 689, pp. 408–15. doi:  10.1016/j.jallcom.2016.07.052 CrossRefGoogle Scholar
  31. 31.
    [31] K. Nakajima, M. Apel and I. Steinbach: Acta Mater., 2006, vol. 54, pp. 3665–72. doi:  10.1016/j.actamat.2006.03.050 CrossRefGoogle Scholar
  32. 32.
    [32] D. Liu, H.V. Atkinson and H. Jones: Acta Mater., 2005, vol. 53, pp. 3807–19. doi:  10.1016/j.actamat.2005.04.028 CrossRefGoogle Scholar
  33. 33.
    P.J. Uggowitzer and D.I. Uhlenhaut: in Thixoforming: Semi-solid Metal Processing, G. Hirt and R. Kopp, eds., Wiley-VCH, Weinheim, 2009, pp. 29–42. doi: 10.1002/9783527623969.ch2
  34. 34.
    [34] C.A. Schneider, W.S. Rasband and K.W. Eliceiri: Nat. Methods, 2012, vol. 9, pp. 671–75. doi:  10.1038/nmeth.2089 CrossRefGoogle Scholar
  35. 35.
    [35] H. Wabusseg, G.C. Gullo, P.J. Uggowitzer, K. Steinhoff and H. Kaufmann: J. Mater. Sci., 2002, vol. 37, pp. 1173–78. doi:  10.1023/A:1014315421781 CrossRefGoogle Scholar

Copyright information

© The Minerals, Metals & Materials Society and ASM International 2017

Authors and Affiliations

  • Davi Munhoz Benati
    • 1
  • Kazuhiro Ito
    • 2
  • Kazuyuki Kohama
    • 2
  • Hajime Yamamoto
    • 2
  • Eugenio José Zoqui
    • 1
    Email author
  1. 1.Department of Materials and Manufacturing Engineering, School of Mechanical EngineeringUniversity of CampinasCampinasBrazil
  2. 2.Research Division of Materials Joining Mechanism, Department of Welding Mechanism, Joining and Welding Research InstituteOsaka UniversityIbarakiJapan

Personalised recommendations