The Effect of Grain Refinement and Cooling Rate on the Hot Tearing of Wrought Aluminium Alloys

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Using modifications to the Rappaz-Drezet-Gremaud hot tearing model, and using empirical equations developed for grain size and dendrite arm spacing (DAS) on the addition of grain refiner for a range of cooling rates, the effect of grain refinement and cooling rate on hot tearing susceptibility has been analysed. It was found that grain refinement decreased the grain size and made the grain morphology more globular. Therefore refining the grain size of an equiaxed dendritic grain decreased the hot tearing susceptibility. However, when the alloy was grain refined such that globular grain morphologies where obtained, further grain refinement increased the hot tearing susceptibility. Increasing the cooling decreased the grain size and made the grain morphology more dendritic and therefore increased the likelihood of hot tearing. The effect was particularly strong for equiaxed dendritic grain morphologies; hence grain refinement is increasingly important at high cooling rates to obtain more globular grain morphologies to reduce the hot tearing susceptibility.

Info:

Periodical:

Materials Science Forum (Volumes 519-521)

Edited by:

W.J. Poole, M.A. Wells and D.J. Lloyd

Pages:

1675-1680

DOI:

10.4028/www.scientific.net/MSF.519-521.1675

Citation:

M. Easton et al., "The Effect of Grain Refinement and Cooling Rate on the Hot Tearing of Wrought Aluminium Alloys", Materials Science Forum, Vols. 519-521, pp. 1675-1680, 2006

Online since:

July 2006

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Price:

$35.00

[1] J.F. Grandfield, C.J. Davidson, and J.A. Taylor: Light Metals 2001. (2001): The Metals, Minerals and Materials Society: p.911.

[2] M. Rappaz, J. -M. Drezet, and M. Gremaud: Metall. Mater. Trans. A, Vol. 30A, (1999), p.449.

[3] M.A. Easton, et al.: Materials Forum, Vol. 28, (2004), p.224.

[4] J.F. Grandfield, et al.: 2nd International light metals technology conference. (2005). St. Wolfgang, Austria: p.75.

[5] M. M'Hamdi, et al.: Aluminium, Vol. 78, (2002), p.847.

[6] M.A. Easton and D.H. StJohn: Light Metals 2001. (2001): The Minerals, Metals and Materials Society, Warrendale, Pensylvania: p.927.

[7] M.A. Easton and D.H. StJohn: Metall. Mater. Trans. A, Vol. 36A, (2005), p. (1911).

[8] M.A. Easton and D.H. StJohn: To be published.

[9] M.C. Flemings, T.Z. Kattamis, and B.P. Bardes: AFS Trans., Vol. 99, (1991), p.501.

[10] W. Kurz and D. Fisher, Fundamentals of solidification, 4th edition. (1998): Trans Tech Publications, Switzerland.

[11] D. Warrington and D.G. McCartney: Cast Metals, Vol. 3, (1991), p.202.

[12] J.M.V. Quaresma, C.A. Santos, and A. Garcia: Metall. Mater. Trans. A, Vol. 31A, (2000), p.3167.

[13] D.J. Lahaie and M. Bouchard: Metall. Mater. Trans B, Vol. 32B, (2001), p.697.

[14] Ø. Nielsen, B. Appolaire, H. Combeau, and A. Mo: Metall. Mater. Trans. A, Vol. 32A, (2001), p. (2049).

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