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Microstructural Development in Al-Ni Alloys Directionally Solidified under Unsteady-State Conditions

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Abstract

Three Al-Ni hypoeutectic alloys were directionally solidified under upward unsteady-state heat-flow conditions. Primary (λ 1) and secondary (λ 2) dendrite arm spacings were measured along the castings for all alloys and correlated with transient solidification thermal variables. A combined theoretical and experimental approach was used to quantitatively determine such thermal variables, i.e., transient metal/mold heat-transfer coefficients, tip growth rates, thermal gradients, tip cooling rates, and local solidification time. The article also focuses on the dependence of dendrite arm spacings on the alloy solute content. Furthermore, the experimental data concerning the solidification of Al-1.0, 2.5, and 4.7 wt pct Ni alloys are compared with the main predictive dendritic models from the literature.

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Notes

  1. ThermoCalc software is an exclusive copyright property of the STT Foundation (Foundation of Computational Thermodynamics, Stockholm).

Abbreviations

A :

constant of the primary dendritic spacing power law (dimensionless)

a 2 :

secondary dendrite calibration factor (dimensionless)

B :

constant of the secondary dendritic spacing power law (dimensionless)

C :

constant of Eq. [3] (dimensionless)

c :

specific heat (J·kg−1·K−1)

c′ :

pseudospecific heat (J·kg−1·K−1)

C 0 :

alloy solute concentration (wt pct)

C E :

eutectic composition (wt pct)

D :

solute diffusivity (m2·s−1)

f s :

local solid fraction (pct)

G 0 ε :

characteristic parameter (60,000 × 6 K·m−1)

\( \ifmmode\expandafter\bar\else\expandafter\fi{G}^{{E,B}} \) :

partial excess Gibbs energies of Al in the bulk (J·mol−1)

\( \ifmmode\expandafter\bar\else\expandafter\fi{G}^{{E,S}} \) :

partial excess Gibbs energies of Al in the surface (J·mol−1)

G L :

temperature gradient (K·m−1)

h g :

global heat-transfer coefficient (W·m−2·K−1)

i :

element position according to x and y axes (dimensionless)

K :

thermal conductivity (W·m−1·K−1)

k 0 :

partition coefficient (dimensionless)

K eq :

equivalent thermal conductivity (W·m−1·K−1)

L :

latent heat (J·kg−1)

L T :

constant of Eq. [6] (dimensionless)

m L :

liquidus slope (K·wt pct−1)

N :

number of moles (dimensionless)

N 0 :

Avogadro’s number (m−3)

\( \ifmmode\expandafter\dot\else\expandafter\fi{q} \) :

rate of energy generation (W·m−3)

R:

gas constant (J·mol−1·K−1)

\( {\mathop T\limits^ \bullet }_{L} \) :

tip cooling rate (K·s−1)

T :

temperature (K)

t :

time (s)

T f :

fusion temperature of the solvent (K)

T liq :

liquidus temperature (K)

T m :

melting temperature (K)

T p :

initial melt temperature (K)

t SL :

local solidification time (s)

T sol :

solidus temperature (K)

V :

molar volume (m3)

V L :

tip growth rate (m·s−1)

X :

molar fraction (dimensionless)

x :

rectangular coordinate (m)

ρ :

density (kg·m−3)

Γ:

Gibbs–Thompson coefficient (K·m)

Δt :

time interval (s)

ΔT :

difference between liquidus and solidus equilibrium temperatures

λ 1 :

primary dendrite arm spacing (μm)

λ 2 :

secondary dendrite arm spacing (μm)

σ SL :

surface energy (N·m−1)

L :

liquid

M :

mush

S :

solid

References

  1. H. Jones: Mater. Sci. Eng., A, 2005, vols. 413–414, pp. 165–73

    Google Scholar 

  2. V. Mertinger, G. Szabo, P. Barczy, A. Kovacs, G. Czel: Mater. Sci. Forum, 1996, vols. 215–216, pp. 331–38

    Google Scholar 

  3. A. Juarez-Hernandez, H. Jones: Scripta Mater., 1998, vol. 38, pp. 729–34

    Article  CAS  Google Scholar 

  4. Y.X. Zhuang, X.M. Zhang, L.H. Zhu, Z.Q. Hu: Sci. Technol. Adv. Mater., 2001, vol. 2, pp. 37–39

    Article  CAS  Google Scholar 

  5. J.M.V. Quaresma, C.A. Santos, A. Garcia: Metall. Mater. Trans. A, 2000, vol. 31A, pp. 3167–77

    Article  CAS  Google Scholar 

  6. W.R. Osório, A. Garcia: Mater. Sci. Eng., A, 2002, vol. 325, pp. 103–11

    Article  Google Scholar 

  7. W.R. Osório, C.A. Santos, J.M.V. Quaresma, A. Garcia: J. Mater. Proc. Technol., 2003, vols. 143–144, pp. 703–09

    Article  CAS  Google Scholar 

  8. W.R. Osório, P.R. Goulart, G.A. Santos, C. Moura Neto, A. Garcia: Metall. Mater. Trans. A, 2006, vol. 37A, pp. 2525–38

    Article  Google Scholar 

  9. J.D. Hunt: Int. Conf. Solidification and Casting of Metals, The Metals Society, London, 1979, pp. 3–9

    Google Scholar 

  10. W. Kurz, J.D. Fisher: Acta Metall., 1981, vol. 29, pp. 11–20

    Article  CAS  Google Scholar 

  11. W. Kurz, J.D. Fisher: Fundamentals of Solidification, Trans Tech Publications, Aedermannsdorf, Switzerland, 1992, pp. 85–90

    Google Scholar 

  12. R. Trivedi: Metall. Mater. Trans. A, 1984, vol. 15A, pp. 977–82

    CAS  Google Scholar 

  13. K. Somboonsuk, J.T. Mason, R. Trivedi: Metall. Mater. Trans. A, 1984, vol. 15A, pp. 967–75

    CAS  Google Scholar 

  14. M. Gündüz, E. Çadirli: Mater. Sci. Eng., A, 2002, vol. 327, pp. 167–85

    Article  Google Scholar 

  15. D. Bouchard, J.S. Kirkaldy: Metall. Mater. Trans. B, 1997, vol. 28B, pp. 651–63

    Article  CAS  Google Scholar 

  16. J.D. Hunt, S.Z. Lu: Metall. Mater. Trans. A, 1996, vol. 27A, pp. 611–23

    Article  CAS  Google Scholar 

  17. D. Bouchard, J.S. Kirkaldy: Metall. Mater. Trans. B, 1996, vol. 27B, pp. 101–13

    Article  CAS  Google Scholar 

  18. A. Mortesen: Metall. Trans. A, 1991, vol. 22A, pp. 569–74

    Google Scholar 

  19. M. Chen, T.Z. Kattamis: Mater. Sci. Eng., A, 1998, vol. 247, pp. 239–47

    Article  Google Scholar 

  20. O.L. Rocha, C.A. Siqueira, A. Garcia: Mater. Sci. Eng., A, 2003, vol. 361, pp. 111–18

    Article  CAS  Google Scholar 

  21. O.L. Rocha, C.A. Siqueira, A. Garcia: Metall. Mater. Trans. A, 2003, vol. 34A, pp. 995–1006

    Article  CAS  Google Scholar 

  22. M.D. Peres, C.A. Siqueira, A. Garcia: J. Alloys Compd., 2004, vol. 381, pp. 168–81

    Article  CAS  Google Scholar 

  23. T. Okamoto, K. Kishitake: J. Cryst. Growth, 1975, vol. 29, pp. 137–46

    Article  CAS  Google Scholar 

  24. U. Feurer and R. Wunderlin, cited by W. Kurz and D.J. Fisher: Fundamentals of Solidification, Trans Tech Publications, Ltd., Aedermannsdorf, Switzerland, 1986, pp. 214–16

  25. D.H. Kirkwood: Mater. Sci. Eng., A, 1985, vol. 73, pp. L1–L4

    Article  CAS  Google Scholar 

  26. J.A.V. Butler: Proc. R. Soc. London, Ser. A, 1932, vol. 135, pp. 348–75

    Article  CAS  Google Scholar 

  27. W. Gasior, J. Pstruś, Z. Moser, A. Krzyżak, K. Fitzner: J. Phase Equilib. Diff., 2002, vol. 24, pp. 40–49

    Article  Google Scholar 

  28. R. Picha, J. Vřešťál, A. Kroupa: Calphad, 2004, vol. 28, pp. 141–46

    Article  CAS  Google Scholar 

  29. T.P. Hoar, D.A. Melford: Trans. Faraday Soc., 1957, vol. 53, pp. 315–26

    Article  CAS  Google Scholar 

  30. T. Tanaka, T. Lida: Steel Res., 1994, vol. 65, pp. 21–28

    CAS  Google Scholar 

  31. T. Tanaka, K. Hack, T. Lida, S. Hara: Z. Metallkd., 1996, vol. 87, pp. 380–89

    CAS  Google Scholar 

  32. T. Tanaka, K. Hack, S. Hara: MRS Bull., 1999, vol. 24, pp. 45–50

    CAS  Google Scholar 

  33. M. Gunduz, E. Çardili: Mater. Sci. Eng., A, 2002, vol. 327, pp. 167–85

    Article  Google Scholar 

  34. C.A. Santos, J.M.V. Quaresma, A. Garcia: J. Alloys Compd., 2001, vol. 319, pp. 174–86

    Article  CAS  Google Scholar 

  35. I.L. Ferreira, J.E. Spinelli, J.C. Pires, A. Garcia: Mater. Sci. Eng., A, 2005, vol. 408, pp. 317–25

    Article  CAS  Google Scholar 

  36. F.P. Incropera, D.P. Dewit: Fundamentals of Heat and Mass Transfer, Wiley, New York, NY, 1990, pp. 56–62

    Google Scholar 

  37. V.L. Voller, C.R. Swaminathan: Numer. Heat Transfer Part B, 1991, vol. 19, pp. 175–89

    Article  Google Scholar 

  38. M.V. Canté, K.S. Cruz, J.E. Spinelli, N. Cheung, A. Garcia: Mater. Lett., 2007, vol. 61, pp. 2135–38

    Article  CAS  Google Scholar 

Download references

Acknowledgments

The authors acknowledge the financial support provided by FAPESP (The Scientific Research Foundation of the State of São Paulo, Brazil), CNPq (The Brazilian Research Council), and FAEPEX–UNICAMP.

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Correspondence to Amauri Garcia.

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Manuscript submitted August 6, 2007.

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Canté, M., Spinelli, J., Ferreira, I. et al. Microstructural Development in Al-Ni Alloys Directionally Solidified under Unsteady-State Conditions. Metall Mater Trans A 39, 1712–1726 (2008). https://doi.org/10.1007/s11661-008-9536-z

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