Abstract
We consider a binary hypoeutectic alloy casting which solidifies in dendritic form in an unreinforced engineering casting and seek to predict its microstructure in a metal matrix composite. We focus on the case where the reinforcement is fixed in space and fairly homogeneously distributed. We assume that the reinforcement does not catalyze heterogeneous nucleation of the solid. We show that the reinforcement can cause several microstructural transitions in the matrix alloy, depending on the matrix cooling rate, the width, A, of interstices left between reinforcing elements, and the initial velocityV of the solidification front. These transitions comprise the following: (1) coalescence of dendrite arms before solidification is complete, causing solidification to proceed in the later stages of solidification with a nondendritic primary phase mapping the geometry of interstices delineated by reinforcement elements; (2) sharp reduction or elimination of microsegregation in the matrix by diffusion in the primary solid matrix phase; and (3) a transition from dendrite to cell formation, these cells featuring significant undercoolings or a nearly plane front configuration when reinforcing elements are sufficiently fine. Quantitative criteria are derived for these transitions, based on previous work on composite solidification, observations from directional solidification experiments, and current solidification theory. Theory is compared with experimental data for aluminum-copper alloys reinforced with alumina fibers and for the dendrite to cell transition using data from directional succinonitrile-acetone solidification experiments. Theory and experiment show good agreement in both systems.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
R. Trivedi, S.H. Han, and J.A. Sekhar: inSolidification of Metal- Matrix Composites, Proc. Conf., Indianapolis, IN, 1989, P.K. Rohatgi, ed., TMS-AIME, Warrendale, PA, 1989, pp. 23–37.
A. Mortensen and I. Jin:Int. Mater. Rev., 1992, vol. 37, pp. 101–28.
A. Mortensen:Mater. Sci. Eng., 1993, vol. A173, pp. 205–12.
A. Mortensen, L.J. Masur, J.A. Cornie, and M.C. Flemings:Metall. Trans. A, 1989, vol. 20A, pp. 2535–47.
A. Mortensen and V. Michaud:Metall. Trans. A, 1990, vol. 21A, pp. 2059–72.
S. Ho and A. Saigal:Scripta Metall. Mater., 1994, vol. 31, pp. 351- 56.
M.A. Khan and P.K. Rohatgi: inMicrostructure Formation during Solidification of Metal Matrix Composites, Proc. Conf., Chicago, IL, 1992, P.K. Rohatgi, ed., TMS, Warrendale, PA, 1993, pp. 97–116.
M.A. Khan and P.K. Rohatgi:Compos. Eng., 1993, vol. 3, pp. 995- 1006.
L.M. Fabietti and J.A. Sekhar: inNature and Properties of Semi-Solid Materials, Proc. Conf., San Diego, CA, 1991; J.A. Sekhar and J. Dantzig, eds., TMS Warrendale, PA, 1991, pp. 41–67.
L.M. Fabietti and J.A. Sekhar:Metall. Trans. A, 1992, vol. 23A, pp. 3361–68.
L.M. Fabietti and J.A. Sekhar:J. Mater. Sci., 1994, vol. 29, pp. 473- 77.
A. Mortensen and M.C. Flemings:Metall. Mater. Trans. A, 1996, vol. 27A, pp. 595–609.
N.F. Dean, A. Mortensen, and M.C. Flemings: inPrinciples of Solidification of Cast Composites, Proc. Conf., Chicago, IL, 1992, P.K. Rohatgi, ed., TMS, Warrendale, PA, 1993, pp. 83–96.
W. Wang, F. Ajersch, and J.P.A. Löfvander:Mater. Sci. Eng., 1994, vol. A187, pp. 65–75.
A. Mortensen, M.N. Gungor, J.A. Cornie, and M.C. Flemings:J. Met., 1986, vol. 38, pp. 30–35.
J.D. Bryant, L. Christodoulou, and J.R. Maisano:Scripta Metall. Mater., 1990, vol. 24, pp. 33–38.
A. Luo:Scripta Metall. Mater., 1994, vol. 31, pp. 1253–58.
R. Trivedi and W. Kurz:Int. Mater. Rev., 1994, vol. 39, pp. 49–74.
M.C. Flemings:Solidification Processing, McGraw-Hill, New York, NY, 1974, pp. 328–34 and 141-46.
E.E. Underwood:Quantitative Stereology, 1st ed., Addison-Wesley Publishing Company, Reading, MA, 1970, ch. 4.
J.A. Sekhar and R. Trivedi:Mater. Sci. Eng., 1989, vol. Al14, pp. 133–46.
L.M. Fabietti, V. Seetharaman, and R. Trivedi:Metall. Trans. A, 1990, vol. 21A, pp. 1299–1310.
J.A. Sekhar and R. Trivedi:Mater. Sci. Eng., 1991, vol. A147, pp. 9- 21.
K.P. Young and D.H. Kirkwood:Metall. Trans. A, 1975, vol. 6A, pp. 197–205.
A. Mortensen:Metall. Trans. A, 1989, vol. 19A, pp. 247–53.
M.N. Gungor, J.A. Cornie, and M.C. Flemings: inCast Reinforced Metal Composites, Proc. Conf., Chicago, IL, 1988, S.G. Fishman and A.K. Dhingra, eds., ASM INTERNATIONAL, Metals Park, OH, 1988, pp. 39–45.
A. Mortensen, J.A. Cornie, and M.C. Flemings:Metall. Trans. A, 1988, vol. 19A, pp. 709–21.
J.D. Hunt and S.Z. Lu:Mater. Sci. Eng., 1993, vol. A173, pp. 79–83.
S.Z. Lu and J.D. Hunt:J. Cryst. Growth, 1992, vol. 123, pp. 17–34.
A. Karma and P. Pelcé:Phys. Rev. A, 1989, vol. 39, pp. 4162–69.
N.F. Dean, A. Mortensen, and M.C. Flemings:Metall. Mater. Trans. A, 1994, vol. 25A, pp. 2295–2301.
W. Kurz and D.J. Fisher:Fundamentals of Solidification, 3rd ed., Trans Tech Publications, Aedermannsdorf, Switzerland, 1989, pp. 289–92.
H.D. Brody and M.C. Flemings:Trans. TMS-AIME, 1966, vol. 236, pp. 615–24.
C.F. Pezzee and D.C. Dunand:Acta Metall. Mater, 1994, vol. 42, pp. 1509–24.
A.M. Redsten, E.M. Klier, A.M. Brown, and D.C. Dunand:Mater. Sci. Eng., 1995, in press.
Q.F. Li, D.G. McCartney, and A.M. Walker:J. Mater. Sci., 1991, vol. 26, pp. 3565–74.
D.J. Lloyd:Compos. Sci. Technol., 1989, vol. 35, pp. 159–79.
H. Lagacé and D.J. Lloyd:Can. Metall. Q., 1989, vol. 28, pp. 145–52.
D. Lloyd: inMetal Matrix Composites—Processing, Microstructure and Properties, 12th Risø Int. Symp. on Materials Science, Proc. Conf., Riso, Denmark, 1991, N. Hansen, D. Juul-Jensen, T. Leffers, H. Lilholt, T. Lorentzen, A.S. Pedersen, O.B. Pedersen, and B. Ralph, eds., Risø National Laboratory, Roskilde, Denmark, 1991, pp. 81–99.
S. Gowri and F.H. Samuel:Metall. Trans. A, 1992, vol. 23A, pp. 3369–76.
A. Kolsgaard, L. Arnberg, and S. Brusethaug:Mater. Sci. Eng., 1993, vol. A173, pp. 243–50.
P.K. Rohatgi, K. Pasciak, C.S. Narendranath, S. Ray, and A. Sachdev:J. Mater. Sci., 1994, vol. 29, pp. 5357–66.
A.P. Majidi, J.M. Yang, and T.W. Chou: inInterfaces in Metal Matrix Composites, Proc. Conf., New Orleans, LA, 1986, A.K. Dhingra and S.G. Fishman, eds., TMS, Warrendale, PA, 1986, pp. 27–44.
Z. Xia, Y. Zhou, Z. Mao, and B. Shang:Metall. Trans. B, 1992, vol. 23B, pp. 295–302.
Z. Xia, Z. Mao, and Y. Zhou:Z Metallkd., 1991, vol. 82, pp. 766- 68.
M.P. Watson and J.D. Hunt:Metall. Trans. A, 1977, vol. 8A, pp. 1793–98.
M. Gunduz and J.D. Hunt:Acta Metall, 1985, vol. 9, pp. 1651–72.
J.B. Murphy:Acta Metall., 1961, vol. 9, pp. 563–69.
L.J. Masur, A. Mortensen, J.A. Cornie, and M.C. Flemings:Metall. Trans. A, 1989, vol. 20A, pp. 2549–57.
Author information
Authors and Affiliations
Additional information
This article is based on a presentation made at the “Analysis and Modeling of Solidification” symposium as part of the 1994 Fall meeting of TMS in Rosemont, Illinois, October 2–6, 1994, under the auspices of the TMS Solidification Committee.
Rights and permissions
About this article
Cite this article
Mortensen, A., Flemings, M.C. Solidification of binary hypoeutectic alloy matrix composite castings. Metall Mater Trans A 27, 595–609 (1996). https://doi.org/10.1007/BF02648949
Issue Date:
DOI: https://doi.org/10.1007/BF02648949