Skip to main content
Log in

Effect of Preconditioning and Inoculation on Graphite Nodule Count and Their Size Distribution in Spheroidal Graphite (SG) Cast Iron: A Study to Minimise Rejection of Castings Due to Shrinkage Porosity

  • Published:
International Journal of Metalcasting Aims and scope Submit manuscript

Abstract

This paper attempts to investigate the effect of preconditioning and inoculation on nodule count and their size distribution to eliminate shrinkage porosity in spheroidal graphite (SG) iron castings. Studies were conducted on various heats of SG iron prepared for differential case casting with and without the addition of 0.1% Al, Zr, Ca–FeSi alloy as preconditioner and Ca–Ce–FeSi alloy was used as an inoculant. It was found that the combined effect of preconditioning and inoculation significantly improves nodule count and nodule size distribution which subsequently reduces the number of castings containing shrinkage porosity. The shrinkage quantity (Q) was found to reduce from 10 to 2.4%. Graphite nodule count and their size distribution were found to be important factors for controlling shrinkage porosity, and it was observed that preconditioning substantially improves the percentage of small size (5–15 µm diameter) graphite nodules. Higher nodule count reduces chances of shrinkage but simply having higher graphite nodule count of similar size does not help in minimising or elimination of shrinkage, it is necessary to have nodules of different sizes in a significant proportion.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6

Similar content being viewed by others

References

  1. E. Foglio et al., Int. J. Metalcast. 11(1), 33 (2017). https://doi.org/10.1007/s40962-016-0112-9

    Article  Google Scholar 

  2. Nicolás Tenaglia et al., Int. J. Cast Met. Res. (2016). https://doi.org/10.1080/13640461.2015.1106783

    Google Scholar 

  3. M. Chisamera, I. Riposan, S. Stan, P. Toboc, T. Skaland, D. White, Shrinkage evaluation in ductile iron as influenced by mould media and inoculant type. Int. J. Cast Met. Res. 24(1), 28–36 (2013). https://doi.org/10.1179/136404610X12816241546618

    Article  Google Scholar 

  4. S.S. Sholapurwalla, Capturing the complexities of ductile iron solidification through simulation. Am. Foundry Soc. Trans. 116, 25–30 (2008)

    Google Scholar 

  5. K.K. Singh, S.K. Sethy, Int. J. Cast Met. Res. 26(3), 168–175 (2013)

    Article  Google Scholar 

  6. A. Regordosa, N. Llorca-Isern, Int. J. Metalcast. (2016). https://doi.org/10.1007/s40962-016-0120-9

    Google Scholar 

  7. C. Hartung, D. White, K. Copi et al., Int. Metalcast. 8, 7 (2014). https://doi.org/10.1007/BF03355577

    Article  Google Scholar 

  8. I. Riposan, M. Chisamera, V. Uta et al., Int Metalcast. 8, 65 (2014). https://doi.org/10.1007/BF03355583

    Article  Google Scholar 

  9. E. Fraś, H. López, Int. Metalcast. 4, 35 (2010). https://doi.org/10.1007/BF03355497

    Article  Google Scholar 

  10. S.S. Ojo, I. Riposan, Mater. Sci. Technol. 28, 5 (2012)

  11. M. Popescu, R. Zavadil, M. Sahoo, Int. Metalcast. 3, 53 (2009). https://doi.org/10.1007/BF03355441

    Article  Google Scholar 

  12. I. Riposan, M. Chisamera, S. Stan, P. Toboc, C. Ecob, D. White, Al,Zr–FeSi preconditioning of grey cast irons. Mat. Sci. Technol. 24(5), 579–584 (2008). https://doi.org/10.1179/174328408X298842

    Article  Google Scholar 

  13. D. White, Avoiding Shrinkage defects and maximizing yield in ductile iron (2012), Paper 12-081.pdf, AFS Proceedings

  14. T. Skaland, Ductile iron shrinkage control through graphite nucleation and growth. Int. J. Cast Met. Res. 16(1–3), 11–16 (2003). https://doi.org/10.1080/13640461.2003.11819551

    Article  Google Scholar 

  15. G. Alonso, D.M. Stefanescu et al., Int. J. Metalcast. (2016). https://doi.org/10.1007/s40962-016-0094-7

    Google Scholar 

  16. S. Lekakh, V. Richards, K. Peaslee, Int. Metalcast. 3, 25 (2009). https://doi.org/10.1007/BF03355456

    Article  Google Scholar 

  17. T. Kanno et al., Int. J. Metalcast. (2016). https://doi.org/10.1007/s40962-016-0111-x

    Google Scholar 

  18. G. Alonso, D.M. Stefanescu et al., Int. J. Cast Met. Res. (2016). https://doi.org/10.1080/13640461.2016.1165459

    Google Scholar 

  19. S.N. Lekakh, B. Hrebec, Int. Metalcast. 10, 389 (2016). https://doi.org/10.1007/s40962-016-0053-3

    Article  Google Scholar 

  20. S. Sasaki, K. Ono, Application of ultrasonic testing techniques to the quality evaluation of cast iron rolls. Am. Foundry Soc. Trans. 76, 169–173 (1968)

    Google Scholar 

  21. Xiaogang Diao et al., Int. J. Mod. Phys. B 23(6 & 7), 1853–1860 (2009)

    Article  Google Scholar 

Download references

Acknowledgements

Authors gratefully acknowledge OCL Iron and Steel Ltd. (Amtek India) located in Bhiwadi, Rajasthan, India, for permitting to conduct the experiments and providing the materials required for this study.

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Mohd. Nadeem Bhat.

Appendix

Appendix

UT inspection

UT apparatus

Einstein-II TFT Ultrasonic flaw tester

Probe

MODSONIC MMEB4H

10Ø–4 MHz

Frequency

4 MHz

Standardisation

V2-Block

Surface preparation

Grinding wheel

Couplant

Grease

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Nadeem Bhat, M., Afzal Khan, D.M. & Singh, K.K. Effect of Preconditioning and Inoculation on Graphite Nodule Count and Their Size Distribution in Spheroidal Graphite (SG) Cast Iron: A Study to Minimise Rejection of Castings Due to Shrinkage Porosity. Inter Metalcast 13, 89–97 (2019). https://doi.org/10.1007/s40962-018-0230-7

Download citation

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s40962-018-0230-7

Keywords

Navigation