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HomeMaterials Science ForumMaterials Science Forum Vol. 630Grain Refinement and Hot Tearing of Aluminium...

Grain Refinement and Hot Tearing of Aluminium Alloys - How to Optimise and Minimise

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Abstract:

Grain refinement and hot tearing are important key factors affecting the quality of castings. There have been substantial advances in the understanding of both of these phenomena over the last two decades. The paper discusses strategies for obtaining the lowest cost grain refiner addition and provides an explanation for how the refinement of equiaxed grains leads to a reduction in hot tear susceptibility. However, it also provides a warning that adding more grain refiner may not be better for reducing hot tear susceptibility. Alloy factors affecting hot tearing are also discussed. Finally, a list of six key considerations is provided to help casthouse and foundry engineers when trying to optimise grain refinement and reduce hot tearing.

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Aluminium Cast House Technology XI

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Periodical:

Materials Science Forum (Volume 630)

Pages:

213-221

DOI:

https://doi.org/10.4028/www.scientific.net/MSF.630.213

Citation:

Cite this paper

Online since:

October 2009

Authors:

Mark Easton, David H. StJohn, Lisa Sweet

Keywords:

6000 Series Alloys, Casting, Grain Refinement, Hot Tearing

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