Microstructure Characterizations of Hypereutectic Al-Si Alloys with Different Undercooling Levels

Abstract:

Microstructural variation is quantitatively characterized by measured undercooling. For neareutectic Al-13wt%Si alloys, microstructure transitions, which include a phase change from eutectic to primary α-Al dendrite plus eutectic and a morphological change from α-Al dendrite to equiaxed Al grains, were observed with increasing undercooling levels. For hypereutectic Al-Si alloys, microstructure transitions, which include a morphological change of primary and eutectic Si crystals, were also obtained quantitatively by increasing undercooling.

• Periodical: Materials Science Forum (Volumes 449-452)
• Pages: 169-172
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.449-452.169
• Online since: March 2004
• Authors: H.S. Kang, W.Y. Yoon, Kwon H. Kim, M.H. Kim, Eui Pak Yoon
• Keywords: Hypereutectic Al-Si, Morphological Changes Of Primary And Eutectic Si, Undercooling

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