Skip to main content
SpringerLink
Log in

The influence of convection during solidification on fragmentation of the mushy zone of a model alloy

  • Published:
Metallurgical and Materials Transactions A Aims and scope Submit manuscript

Abstract

Experiments have been conducted to observe fragmentation events in a model alloy (succinonitrile and acetone) solidifying in the presence of forced convection in the superheated melt. Measurements of fragmentation rates have been made, and an attempt was made to relate the results to the controllable parameters of the system. A microscope-video system recorded the mushy zone-melt interface, and the fragmentation process and fragmentation rates could be determined from a frame-by-frame analysis of the video images. Experiments were conducted for varying cooling rates, overall temperature differences, melt flow rates, and for two different concentrations of acetone (1.3 and 6.1 wt pct). Significant dendritic fragmentation occurred for all runs. In addition, the influence of buoyancy forces is clearly evident from particle motion near the mushy zone-melt interface. Fragmentation rates appear to correlate well with the magnitude of particle velocities near the interface, with increasing fragmentation being associated with higher particle velocity magnitude (either in the same or the opposite direction to the mean flow) for the 1.3 wt pct acetone mixture. However, the correlation is quite different for the higher concentration. The relationship between these results and the possible mechanisms for fragmentation are discussed. Although it appears that either constitutional remelting or capillary pinching are likely of importance, hydrodynamic shear forces or some other mechanism as yet undiscovered cannot be completely discounted, although circumstantial evidence suggests that mechanical shearing is inconsistent with observations made both here and already in published literature. The results provide a step in the development of solidification models that incorporate fragmentation processes in the mushy zone as an important mechanism of grain refinement and a potential source of macrosegregation in ingots and large castings.

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

Access this article

Log in via an institution

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

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  1. Q.T. Fang: ALCOA Technical Center, ALCOA Center, PA, private communication, 1989.

  2. C. Vives: Int. J. Heat Mass Transfer, 1990, Vol. 33, pp. 2585–98.

    Article  CAS  Google Scholar 

  3. P. Desnain, F. Durand, Y. Fautrelle, P. Bloch, J.L. Meyer, and J.P. Riquet. Light Metals 1988, TMS, Warrendale, PA, 1988, pp. 487–93.

    Google Scholar 

  4. K.A. Jackson, J.D. Hunt, D.R. Uhlmann, and T.P. Seward: Trans. TMS-AIME, 1966, vol. 236, pp. 149–58.

    CAS  Google Scholar 

  5. M.S. Christenson and F.P. Incropera: Int. J. Heat Mass Transfer, 1989, vol. 30, pp. 47–68.

    Article  Google Scholar 

  6. M.S. Christenson, W.B. Bennon, and F.P. Incropera, Int. J. Heat Mass Transfer, 1989, vol. 30, pp. 69–79.

    Article  Google Scholar 

  7. E.R. Rubinstein: Ph.D. Thesis, Rensselaer Polytechnic Institute, Troy, NY, 1989.

  8. S.C. Huang and M.E. Glicksman: Acta Metall., 1981, vol. 29, pp. 717–34.

    Article  CAS  Google Scholar 

  9. P.W. Voorhees: Metall. Trans. A, 1990, vol. 21A, pp. 27–37.

    CAS  Google Scholar 

  10. D.M. Smith, J.A. Eady, L.M. Hogan, and D.W. Irwin: Metall. Trans. A, 1991, vol. 22A, pp. 575–84.

    CAS  Google Scholar 

  11. R.C. Kerr, A.W. Woods, M.G. Worster, and H.E. Huppert: Nature, 1989, vol. 340, pp. 357–62.

    Article  CAS  Google Scholar 

  12. Q.T. Fang and M.J. Bruno: in Light Metals 1991, E.L. Rooy, ed., TMS, Warrendale, PA, 1991, p. 856.

    Google Scholar 

  13. N.B. Bryson, J.G. McCubbin, C.M. Read, P.G. Enright, and S.C. Food: International Patent Application Published under the Patent Cooperation Treaty, PCT/CA91/00216, International Publication Number WO 91/19578, 1991.

  14. F. Durand: in Interactive Dynamics of Convection and Solidification, S.H. Davis, H.E. Huppert, and U. Mueller eds., NATO ASI Series E, Kluwer, Hungham, MA, 1992, vol. 219, pp. 55–59.

    Google Scholar 

  15. C.J. Paradies, G.T. Kim, M.E. Glicksman, and R.N. Smith: in Modeling of Casting, Welding and Advanced Solidification Processes—VI, T.S. Piwonka, V. Voller, and L. Katgerman eds., TMS, Warrendale, PA, 1993, pp. 309–16.

    Google Scholar 

  16. C.J. Paradies: Ph.D. Thesis, Rensselaer Polytechnic Institute, Troy, NY, 1993.

  17. R. Zakhem, P.D. Weidman, and H.D. deGroh III, Proc. 1st Int. Conf. on Transport Phenomena in Processings, S.I. Guceri, ed., Technomic Publishing Co., Lancaster, PA, 1993, pp. 219–28.

    Google Scholar 

Download references

Author information

Authors and Affiliations

  1. CH-1015, Lausanne, Switzerland

    C. J. Paradies (Postdoctoral Fellow)

  2. Department of Mechanical Engineering, Aeronautical Engineering, and Mechanics, Rensselaer Polytechnic Institute, 12180-3590, Troy, NY

    R. N. Smith (Professorz)

  3. Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, 12180-3590, Troy, NY

    M. E. Glicksman (John Tod Horton Professor of Materials Engineering)

Authors
  1. C. J. Paradies
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. R. N. Smith
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. M. E. Glicksman
    View author publications

    You can also search for this author in PubMed Google Scholar

Additional information

C. J. PARADIES, formerly Graduate Research Assistant, Rensselaer Polytechnic Institute

Rights and permissions

Reprints and permissions

About this article

Cite this article

Paradies, C.J., Smith, R.N. & Glicksman, M.E. The influence of convection during solidification on fragmentation of the mushy zone of a model alloy. Metall Mater Trans A 28, 875–883 (1997). https://doi.org/10.1007/s11661-997-1016-3

Download citation

  • Received:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s11661-997-1016-3

Keywords

Search

Navigation