Abstract
Effect of oxide level on porosity formation in an A356 alloy was investigated using micro-focus X-ray imaging and directional solidification technology. The increase of oxide level in liquid aluminum was achieved by violently stirring molten metal at elevated temperature. During solidification, the increased oxide content in melt significantly increases the amount of active nucleation sites for porosity and thus raises the nucleation temperature of pores. The fast growth of those early formed pores further restrains the succeeding nucleation operations of new pores in local regions and results in a considerable reduction in pore density. It was also found that the melt with high oxide content shows less dependency of growth rate reduction with local temperature.
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Liao, H., Song, W., Wang, Q., Zhao, L., Fan, R. (2012). Effect of Oxide Level on Pore Formation in A356 Alloy by X-Ray Imaging and Directional Solidification Technology. In: Weiland, H., Rollett, A.D., Cassada, W.A. (eds) ICAA13 Pittsburgh. Springer, Cham. https://doi.org/10.1007/978-3-319-48761-8_221
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DOI: https://doi.org/10.1007/978-3-319-48761-8_221
Publisher Name: Springer, Cham
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