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Journal of Thermal Analysis and Calorimetry

, Volume 138, Issue 4, pp 2529–2540 | Cite as

Simultaneous thermal and contraction/expansion analyses of cast iron solidification process

  • Stelian Stan
  • Mihai Chisamera
  • Iulian RiposanEmail author
  • Eduard Stefan
  • Loredana Neacsu
  • Ana Maria Cojocaru
  • Iuliana Stan
Article
  • 70 Downloads

Abstract

Simultaneous thermal and contraction/expansion analysis of hypoeutectic grey (lamellar graphite) and ductile (nodular graphite) cast irons solidification is recorded, using an equipment with a special designed ceramic cup, incorporating a thermocouple and contraction/expansion measuring device. Both cooling and contraction/expansion curves and their specific parameter values are displayed in a real time. The two compared cast irons occupy different and opposite positions during solidification process evolution: lower level of temperatures at the beginning and especially at the end of solidification, but higher level during the eutectic reaction for ductile cast irons. In the tested conditions, solidification of hypoeutectic cast irons with lamellar graphite is characterized by a greater undercooling during the eutectic reaction (lower ΔT1 and ΔT2, referring to the metastable eutectic temperature), with higher value for eutectic recalescence (ΔTr) and the maximum recalescence rate. Iron castings, including nodular graphite (ductile irons), show an end of solidification at higher undercooling (ΔT3), with less negative pick level of the first derivative of cooling curve. More graphitic initial expansion [εdi(gr)], which favours the shrinkage formation, characterized nodular graphite iron castings. There is a good relationship between some parameters on the cooling curves and corresponding events on the contraction/expansion curves, such as solidification undercooling degrees, comparing to metastable eutectic temperature, and graphitic expansion [εdi(gr)] for both tested cast irons: higher the level of ΔTr, and of ΔT1, ΔT2, ΔT3 (less negative) and GRF1 (graphitic factor), higher the [εdi(gr)] level is.

Keywords

Solidification Thermal analysis Cooling curve analysis Contraction/expansion curve analysis Recalescence Solidification undercooling degree Graphitic expansion 

Notes

Acknowledgements

This work was partially financed by a Grant of the Romanian National Authority for Scientific Research and Innovation, CNCS/CCCDI—UEFISCDI, Project No. PN-III-P2-2.1-PED-2016-1793, within PNCDI III.

References

  1. 1.
    Riposan I, Skaland T. Modification and inoculation of cast iron. In: Stefanescu DM, editor. Cast iron science and technology handbook. New York: American Society of Materials; 2017. p. 160–76.Google Scholar
  2. 2.
    Stan S, Chisamera M, Riposan I, Barstow M. Applications of thermal analysis to monitor the quality of hypoeutectic cast irons during solidification in sand and metal moulds. J Therm Anal Calorim. 2012;110(3):1185–92.CrossRefGoogle Scholar
  3. 3.
    Riposan I, Chisamera M, Stan S. Application of cooling curve analysis in solidification pattern and structure control of grey cast irons. J Therm Anal Calorim. 2018;132(2):1017–28.CrossRefGoogle Scholar
  4. 4.
    Stefanescu DM. Thermal analysis-theory and applications in metalcasting. J Metalcasting. 2015;9(1):7–22.CrossRefGoogle Scholar
  5. 5.
    Sparkman D. Microstructure by thermal analysis. AFS Trans. 2011;119:413–9.Google Scholar
  6. 6.
    Klancnik U, Habjan J, Klancnik G, Medved J. Thermal analysis of indefinite chill cast iron modified with ferrovanadium and ferrotungsten. J Therm Anal Calorim. 2017;127:71–8.CrossRefGoogle Scholar
  7. 7.
    Krupinski M, Krupinska B, Labisz K, Rdzawski Z, Borek W. Influence of cooling rate on crystallisation kinetics on microstructure of cast zinc alloys. J Therm Anal Calorim. 2014;118(2):1361–7.CrossRefGoogle Scholar
  8. 8.
    Krupinski M, Krupinska B, Rdzawski Z, Labisz K, Tanski T. Additives and thermal treatment influence on microstructure of nonferrous alloys. J Therm Anal Calorim. 2015;120(3):1573–83.CrossRefGoogle Scholar
  9. 9.
    Chisamera M, Riposan I, Stan S, Toboc P, Skaland T, White D. Shrinkage evaluation in ductile iron as influenced by mold media and inoculant type. Int J Cast Mer Res. 2011;24(1):28–36.CrossRefGoogle Scholar
  10. 10.
    Chisamera M, Riposan I, Stan S, Barstow M. Simultaneous cooling and contraction/expansion curve analysis during ductile iron solidification. AFS Trans. 2012;120:375–88.Google Scholar
  11. 11.
    Stan S, Chisamera M, Riposan I, Neacsu L, Cojocaru AM, Stan I. Technique incorporating cooling and contraction/expansion analysis to illustrate shrinkage tendency in cast irons. IOP Conf Ser Mater Sci Eng. 2017;209:12017.CrossRefGoogle Scholar
  12. 12.
    Stan S, Chisamera M, Riposan I, Neacsu L, Cojocaru AM, Stan I. Integrated system of thermal/dimensional analysis for quality control of metallic melt and ductile iron casting solidification. J Mater Eng Perform. 2018;27(10):5187–96.CrossRefGoogle Scholar
  13. 13.
    Stan S, Chisamera M, Riposan I, Stefan E, Neacsu L, Cojocaru AM, Stan I. Integrated system of thermal/dimensional analysis for quality control of gray and ductile iron castings solidification. 2018 Keith Millis Symp. on Ductile Iron, Hilton Head Island, SC, USA, October 2018. Int J Metalcasting. 2019;13(3):653–65.CrossRefGoogle Scholar
  14. 14.
    Tadesse A, Fredriksson H. Volume change during the solidification of grey cast iron: its relation with the microstructural variation, comparison between experimental and theoretical analysis. Int J Cast Met Res. 2017;30(3):159–70.CrossRefGoogle Scholar
  15. 15.
    Stefanescu DM, Moran M, Boonmee S, Guesser WL. The use of combined liquid displacement and cooling curve analysis in understanding the solidification of cast irons. AFS Trans. 2012;120:365–74.Google Scholar
  16. 16.
    Tadesse A, Fredriksson H. The effects of carbon on the solidification of nodular cast iron—its study with the help of linear variable differential transformer and microstructure analysis. Int J Cast Met Res. 2018;31(2):108–17.CrossRefGoogle Scholar
  17. 17.
    Svidro P, Dioszegi A. On problems of volume change measurements in lamellar cast iron. Int J Cast Met Res. 2014;27(1):26–37.CrossRefGoogle Scholar
  18. 18.
    Alonso G, Loizaga A, Zarrabeitia G, Stefanescu DM, Suarez R. Kinetics of graphite expansion during solidification of lamellar and spheroidal graphite Iron. In: Proceeding of the 119th AFS metalcasting congress; 2014; Paper 14-006.Google Scholar
  19. 19.
    Alonso G, Stefanescu DM, Suarez R. Understanding graphite expansion during the eutectic solidification of cast iron through combined linear displacement and thermal analysis. Int Foundry Res. 2014;66(4):2–12.Google Scholar
  20. 20.
    Thielemann T. Zur Wirkung van Spurenelementen in Gusseisen mit Kugelgraphit. Giessereitechnik. 1970;1:16–24.Google Scholar
  21. 21.
    Sillen RV. Novacast Technologies; 2006. www.novacast.se.
  22. 22.
    Kanno T, Iwami Y, Kang I. Prediction of graphite nodule count and shrinkage tendency in ductile cast iron with 1 cup thermal analysis. J Metalcasting. 2017;11(1):94–100.CrossRefGoogle Scholar
  23. 23.
    Kanno T, Fukuda Y, Kang I, Morinaka M, Nakae H. Prediction of chilling tendency in cast iron using three cups thermal analysis system. J JFS. 1998;70:773–8.Google Scholar
  24. 24.
    Kanno T, Nakae H. Prediction of graphite types and mechanical properties in cast iron using three cups thermal analysis. J JFS. 2000;72:175–80.Google Scholar

Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2019

Authors and Affiliations

  • Stelian Stan
    • 1
  • Mihai Chisamera
    • 1
  • Iulian Riposan
    • 1
    Email author
  • Eduard Stefan
    • 1
  • Loredana Neacsu
    • 1
  • Ana Maria Cojocaru
    • 1
  • Iuliana Stan
    • 1
  1. 1.POLITEHNICA University of BucharestBucharestRomania

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