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Journal of Materials Science

, Volume 43, Issue 4, pp 1471–1479 | Cite as

An examination of effects of solidification parameters on permeability of a mushy zone in castings

  • Danylo B. Oryshchyn
  • Ömer N. DoğanEmail author
Article

Abstract

A model describing the development of dendritic structure and the resulting gradient of flow resistance to interdendritic liquid is presented. The Hagen–Pousielle version of D’Arcy’s equation for flow through a porous structure is developed as a function of cooling rate and liquid volume fraction. Applied to finite elements in a unidirectionally cooled casting model, permeability gradient, feeding flow-rate required to prevent porosity, and mushy-zone liquid pressure drop at this flow rate are evaluated for the simple Fe–2Cr–0.5C and Al–5Cu castings exhibiting asymptotic and linear temperature profiles, respectively. The model shows permeability of the dendritic structure in the mushy zone dropping sharply, approaching the root of solidification front (solidus). Also shown is the effect of relative magnitude of primary and secondary arm spacing. If secondary dendrite arm spacing approaches primary arm spacing, the permeability for flow normal to primary dendrite arms approaches or even surpasses the permeability for flow parallel to primary dendrite arms.

Keywords

Cool Rate Liquid Fraction Mushy Zone Dendritic Structure Volumetric Flow Rate 

Notes

Acknowledgement

This report based upon work supported by the U.S. Department of Energy under Award Number DE-FC36-01ID13981.

References

  1. 1.
    Geiger GH, Poirier DR (1973) Transport phenomena in metallurgy. Addison-Wesley, Reading, p 91Google Scholar
  2. 2.
    Geiger GH, Poirier DR (1973) Transport phenomena in metallurgy. Addison-Wesley, Reading, p 45Google Scholar
  3. 3.
    Duncan AJ, Han Q, Viswanathan S (1999) Metall Mater Trans B 30B:745CrossRefGoogle Scholar
  4. 4.
    Streat N, Weinberg F (1976) Interdendritic fluid flow in a lead–tin alloy. Metall Trans B 7B:417CrossRefGoogle Scholar
  5. 5.
    Murakami K, Shiraishi A, Okamoto T (1983) Interdendritic fluid flow normal to primary dendrite-arms in cubic alloys. Acta Metall 31(9):1417CrossRefGoogle Scholar
  6. 6.
    Nielsen O, Arnberg L, Mo A, Thevik H (1999) Experimental determination of mushy zone permeability in aluminum–copper alloys with equiaxed microstructures. Metall Mater Trans A 30A:2455CrossRefGoogle Scholar
  7. 7.
    Wang CY, Ahuja S, Beckermann C, de Groh III HC (1995) Metall Mater Trans B 26B:111Google Scholar
  8. 8.
    Nasser-Rafi R, Desmunkh R, Poirier DR (1985) Flow of interdendritic liquid and permeability in Pb-20 Wt Pct Sn alloys. Metall Trans A 16A:2263CrossRefGoogle Scholar
  9. 9.
    Santos RG, Melo MLNM (2005) Permeability of interdendritic channels. Mater Sci Eng A 391:151CrossRefGoogle Scholar
  10. 10.
    Sabau AS, Viswanathan S (2002) Microporosity in aluminum alloy casting. Metall Mater Trans B 33B:243CrossRefGoogle Scholar
  11. 11.
    Niyama E, Uchida T, Morikawa M, Saito S (1982) A method of shrinkage prediction and its application to steel casting practice. AFS International Cast Metals Journal, pp 52–63Google Scholar
  12. 12.
    Flemings MC (1974) Solidification processing, materials science and engineering series. McGraw-Hill, New York, NY, p 148Google Scholar
  13. 13.
    Bejan A, Dincer I, Lorente S, Miguel A, Reis H (2004) Porous and complex flow structures in modern technologies. Springer-Verlag, New York, p 10CrossRefGoogle Scholar
  14. 14.
    Horwath JA, Mondolfo LF (1962) Dendritic growth. Acta Metall 10:1037CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  1. 1.DOE National Energy Technology LaboratoryAlbanyUSA

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