Journal of Materials Engineering and Performance

, Volume 28, Issue 1, pp 278–286 | Cite as

Solidification Characteristics of Silicon-Alloyed Ductile Cast Irons

  • Stelian Stan
  • Iulian RiposanEmail author
  • Mihai Chisamera
  • Iuliana Stan


Solidification pattern of three ductile iron compositions [I-2.5%Si; II-4%Si, and III-4%Si-1.6%Mo] is studied, to evaluate the effects of high Si and Mo contents. Inoculation compensates for the negative effect of Mo on eutectic undercooling. The deviation using a sphere as reference of graphite particles is noticeably increased by silicon alloying, when a characteristic of the graphite particles appears have a larger perimeter, resulting in a large category [IV, V and VI forms, ISO 945]. The sphericity shape factor (SSF) considering the real perimeter of particle is recommended in the nodularity evaluation in high-Si ductile iron, instead of the roundness shape factor, involving maximum ferret, presently incorporated in the ISO 945 standard. The higher the minimum acceptable SSF is, the greater difference in nodularity, between conventional and Si-alloyed ductile irons. For more than 4%Si, ductile irons are characterized by a medium-quality graphite phase, with prevalent form V-ISO 945 graphite. A specific inoculant, with a powerful action on the graphite particle compactness, especially to promote VI graphite form, is necessary.


ductile iron graphite shape factor inoculation Mg treatment nodularity Si and Si-Mo alloying structure thermal analysis 



This work was partially financed by the grant of the Romanian National Authority for Scientific Research and Innovation, CNCS/CCCDI-UEFISCDI, mobility Grant of the Romanian Ministry of Research and Innovation, CNCS-UEFISCDI, Project Number PN-III-P1-1.1- MC-2018-0207, within PNCDI III. The authors would like to recognize and thank Michael Barstow (Consultant) for reviewing and editing this paper.


  1. 1.
    S. Stan, I. Riposan, M. Chisamera, and M. Barstow, Solidification Pattern of Silicon Alloyed Ductile Cast Irons, 122nd AFS Metalcasting Congress. Fort Worth, TX, USA, 2018, Paper no. 18-022Google Scholar
  2. 2.
    S. Stan, M. Chisamera, I. Riposan, E.L. Neacsu, and A.M. Cojocaru, Structure Characteristics of Silicon Alloyed Ductile Cast Iron, IOP Conference Series: Materials Science Engineering 2018, Vol 416, 012077, doi:10.1088/1757-899x/416/1/012077Google Scholar
  3. 3.
    W. Stets, H. Loblich, G., and Gassner, P. Schumacher, Solution Strengthened Ferritic Ductile Iron According DIN EN 1563:2012, 2013 Keith Millis Symposium on Ductile Iron, Nashville, TN, USA, 2013, p 283–292Google Scholar
  4. 4.
    W. Menk, Development of Cast Iron for Exhaust Applications, 6th European Cast Iron Meeting, Nancy, France, 2014, Paper no. 3Google Scholar
  5. 5.
    S. Xiang, C. Oberg, M. Ekstrom, B. Zhu, and S. Jonson, High-Temperature Corrosion Fatigue Behavior of Ductile Cast Irons for Exhaust Manifolds Applications, Mater. Sci. Forum, 2018, 925, p 369–376CrossRefGoogle Scholar
  6. 6.
    A. Alhussein, M. Risbet, A. Bastien, J.P. Chobaut, D. Balloy, and J. Favergeon, Influence of Silicon and Addition Elements on the Mechanical Behavior of Ferritic Ductile Cast Iron, Mater. Sci. Eng. A, 2014, 605, p 222–228CrossRefGoogle Scholar
  7. 7.
    N. Scheidhauer, C. Dommaschk, and G. Wolf, Oxidation Resistant Cast Iron for High-Temperature Application, Mater. Sci. Forum, 2018, 925, p 393–399CrossRefGoogle Scholar
  8. 8.
    P. Weiss, M. Riebisch, and A. Buhrig-Polaczek, Mechanical Properties and Impact Toughness of Ni and Al Alloyed High Silicon Ductile Iron, Mater. Sci. Forum, 2018, 925, p 304–310CrossRefGoogle Scholar
  9. 9.
    European Patent EP 1 386 976, Registered 30.04.2003Google Scholar
  10. 10.
    L. Dekker and B. Tonn, Occurrence and Behavior of Mo Containing Precipitates in Nodular Cast Iron at High Temperatures, Int. J. Cast Met. Res. 2016, 29(1–2), p 85–91CrossRefGoogle Scholar
  11. 11.
    M. Ekström, and S. Jonsson, High-Temperature Corrosion Fatigue of a Ferritic Ductile Cast Iron in Inert and Corrosive Environments at 700°C, The 10th International Symposium on the Science and Processing of Cast Iron—SPCI10, Mar del Plata, Argentina, Paper 06, 2014Google Scholar
  12. 12.
    A. Ebel, S.Y. Brou, B. Malard, J. Lacaze, D. Monceau, and L. Vaissiere, High-Temperature Oxidation of a High Silicon SiMo Spheroidal Cast Iron in Air with In Situ Change in H2O Content, Mater. Sci. Forum, 2018, 925, p 353–360CrossRefGoogle Scholar
  13. 13.
    I. Riposan and T. Skaland, Modification and Inoculation of Cast Iron, ASM-American Society of Materials Cast Iron Science and Technology Handbook [D.M. Stefanescu Volume Editor], 2017, p 160–176Google Scholar
  14. 14.
    R.B. Gundlach, H. Tian, and B. Bending, Specification, Selection, and Applications of High-Alloy Iron Castings, ASM-American Society of Materials Cast Iron Science and Technology Handbook [D.M. Stefanescu Volume Editor], 2017, p 689–707Google Scholar
  15. 15.
    T. Thielemann, Zur Wirkung van Spurenelementen in Gusseisen mit Kugelgraphit, Giessereitechnik, 1970, 1, p 16–24Google Scholar
  16. 16.
    T. Kanno, Y. Iwami, and I. Kang, Prediction of Graphite Nodule Count and Shrinkage Tendency in Ductile Cast Iron, with 1 Cup Thermal Analysis, Int. J Metalcasting, 2017, 11(1), p 94–100CrossRefGoogle Scholar
  17. 17.
    T. Kanno, Y. Fukuda, M. Morinaka, and H. Nakae, Effect of Alloying Elements on Graphite and Cementite Eutectic Temperature of Cast Iron, J. Jpn. Foundry Soc., 1998, 70, p 465–470Google Scholar
  18. 18.
    O. Gomez and S. Paciornik, Automatic Classification of Graphite in Cast Iron, Microsc. Microanal., 2005, 11, p 363–371CrossRefGoogle Scholar
  19. 19.
    J.C. Russ, The Image Processing Handbook, CRC Press, Boca Raton, 1995Google Scholar
  20. 20.
    S. Stan, M. Chisamera, I. Riposan, N. Ivan, and M. Barstow, Iron Powder Treated Gray Irons: Critical Shape Characteristics for Graphite Nuclei, J. Mater. Eng. Perform., 2012, 21(8), p 1793–1799CrossRefGoogle Scholar
  21. 21.
    ISO 945-4:2015 Microstructure of Cast Irons—Part 4: Determination of Nodularity in Spheroidal Graphite Cast IronsGoogle Scholar
  22. 22.
    GB 9441-88, Metallographic Test for Evaluation of Spheroidal Graphite Cast Iron. (National Standard of the PRC)Google Scholar
  23. 23.
    I. Riposan, V. Uta, S. Stan, R.L. Naro, and D.C. Williams, The Effect of Minimizing Rare Earth Elements during Nodulizing Treatments and the Inoculation of Ductile (S.G.) Iron, AFS Trans., 2014, 122, p 219–236Google Scholar
  24. 24.
    I. Riposan, M. Chisamera, V. Uta, S. Stan, R. Naro, and D. Williams, The Importance of Rare Earth Contribution from Nodulizing Alloys and Their Subsequent Effect on the Inoculation of Ductile Iron, Int. J. Metalcasting, 2014, 8(2), p 65–80CrossRefGoogle Scholar
  25. 25.
    I. Riposan, V. Uta, and S. Stan, Inoculant Enhancer to Increase the Potency of Ca-FeSi Alloy in Ductile Cast Iron, Metall. Res. Technol., 2017, 114(4), p 416CrossRefGoogle Scholar

Copyright information

© ASM International 2018

Authors and Affiliations

  • Stelian Stan
    • 1
  • Iulian Riposan
    • 1
    Email author
  • Mihai Chisamera
    • 1
  • Iuliana Stan
    • 1
  1. 1.Materials Science and Engineering FacultyPOLITEHNICA University of BucharestBucharestRomania

Personalised recommendations