Abstract
In aluminum-silicon cast alloys, the shapes of the silicon phase and the general solidification pattern can be changed by the cooling conditions and by minor additions to the melt. The minor additions either cause modification (sodium, strontium, and other metals) or refine the primary silicon in hypereutectic alloys (phosphorus and elements of Group V-B). Detailed examination of the modified microstructures and analysis of cooling curves are compatible with a modification mechanism involving growth rather than nucleation kinetics.
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References
A. Pacz, U.S. Patent No. 1387900 (1920).
J.D. Edwards, F.C. Frary, and H.V. Churchill, U.S. patent 1410461 (1920).
D.A. Granger and R. Elliott, ASM Handbook, 15 (Materials Park, OH: ASM, 1992), p. 159.
E.L. Rooy, ASM Handbook, 15 (Materials Park, OH: ASM, 1992), p. 743.
H. Morrogh and W.J. Williams, J. Iron Steel Inst. London, 155 (1947), p. 321.
A. Hellawell, Prog. Mat. Sci., 15 (1973), p. 1.
Shu-Zu Lu and A. Hella well, J. Crystal Growth, 73 (1985), p. 316.
M.D. Hanna, Shu-Zu Lu, and A. Hellawell, Met. Trans., 15A (1984), p. 459.
H.A. H. Steen and A. Hellawell, Acta Met., 20 (1972), p. 363.
Shu-Zu Lu and A. Hellawell, Met. Trans., 18A (1987), p. 1721.
M.G. Day, J. Inst. Metals, 98 (1970), p. 57.
W.C. Johnson and H.B. Smartt, Met. Trans., 5A (1974), p. 549.
P.M. Thomas and J.E. Gruzleski, J. Iron and Steel Inst., 211 (1973), p. 426.
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Lu, SZ., Hellawell, A. Modification of Al-Si alloys: Microstructure, thermal analysis, and mechanisms. JOM 47, 38–40 (1995). https://doi.org/10.1007/BF03221405
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DOI: https://doi.org/10.1007/BF03221405