Effect of Heat Treatments in the Silicon Eutectic Crystal Evolution in Al-Si Alloys

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This paper describes the heat treatment effect on the eutectic silicon evolution in the A357 alloy, obtained by semisolid forming process (SSM). The coarsening rate of the silicon was determined by Image Analysis Technique in specimens from rheocasting ingots and thixocasting components. The study was realized in the temperature range from 450 to 550°C by applying heating times between 1 and 24 hours. The results show that during the heat treatment the coarsening and sphereodization of the silicon particles is produced and the fragmentation stages, which are observed in conventional alloys, do not appear. Kinetic silicon growth has been adjusted to the Oswald’s ripening equation.

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Periodical:

Materials Science Forum (Volumes 480-481)

Edited by:

A. Méndez-Vilas

Pages:

367-372

Citation:

A. Forn et al., "Effect of Heat Treatments in the Silicon Eutectic Crystal Evolution in Al-Si Alloys", Materials Science Forum, Vols. 480-481, pp. 367-372, 2005

Online since:

March 2005

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$38.00

[1] M. C. Flemings: Metallurgical Transactions Vol. 22A (1991), p.957.

[2] A. J. Criado, J. A. Martinez, J. M. Gómez de Salazar, F. Molleda: Praktische-Metallographie, 24(4) (1987), p.175.

[3] H. Hu, B. B. Rath: Met. Trans. 1, (1970), p.3181.

[4] J. D. Verhoeven: Fundamentos de Metalurgia Física (Limusa, Mexico 1987).

[5] R. E. Smallman: Modern Physical Metallurgy 4 th ed (Butterworth, London 1985).

[6] V. S. Solomatov: Lunar and Planetary Science XXXIII, (2002).

[7] J. J. Martin: Thesis: An Atomic Scale View on a Model Catalyst Pd Nanoparticles on TiO2 (2002).

[8] L. M. Lifschitz, V. V. Slyozov: J. Phys. Chem. Solids, 19, (1961), p.35.

[9] J. M. Bastidas, A. Forn, M. T. Baile, J. L. Polo and C. L. Torres: Materials and Corrosion 52, (2001), p.691.

[10] E. A. Brandes: Smithells Metalls Reference Book, 6th Ed, (Ed. Butterworths, 1983).