The Microstructure of AlSi7Mg Alloy in as Cast Condition

Abstract:

The complex microstructure of as-cast AlSi7Mg alloy has been investigated. Microstructure observations were done using light microscopy, scanning electron microscopy and transmission electron microscopy. Chemical composition of the microstructure constituents was investigated by means of energy dispersive spectrometry, conducted both during SEM and STEM investigations. Selected area diffraction was used to identify the phases in the alloy. Microstructure of the alloy in the as-cast condition consists of Al-Si eutectic and intermetallic phases in the interdendritic regions. These are: Mg₂Si, α-AlFeMnS, β-AlFeSi and π-AlFeSiMg phases. What is more, number of fine precipitates were found within the α-Al dendrites. Only the occurrence of U1 (MgAl₂Si₂) phase has been confirmed.

• Periodical: Solid State Phenomena (Volume 229)
• Pages: 3-10
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.229.3
• Online since: April 2015
• Authors: Bartłomiej Dybowski*, Bogusława Adamczyk-Cieślak, Kinga Rodak, Iwona Bednarczyk, Andrzej Kiełbus, Jaroslaw Mizera
• Keywords: AlSi7Mg Alloy, As-Cast Condition, Microstructure, Phase Identification, TEM

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