The Porosity Description in Hypoeutectic Al-Si Alloys

Abstract:

Al-Si alloys are the most important group among aluminum casting alloys. They are widely used in automotive and aerospace industries. Chemical modification of the Al-Si alloys leads to formation of fine, fibrous Al-Si eutectic mixture ensuring high mechanical properties. The modification is however known to increase the alloy porosity, which may, in turn, result in decrease of its properties. The following paper presents results of the research on quantitative description of the Al-Si cast alloys porosity and influence of Na modification on the porosity of AlSi9Mg alloy. Porosity in the hypoeutectic Al-Si alloys occurs in four types: shrinkage cavities, shrinkage porosity, isolated gas pores and gas pores surrounded by shrinkage porosity. Na modification leads to increase of shrinkage pores volume fraction.

• Periodical: Key Engineering Materials (Volume 682)
• Pages: 83-90
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.682.83
• Online since: February 2016
• Authors: Bartłomiej Dybowski*, Łukasz Poloczek, Andrzej Kiełbus
• Keywords: Gas Porosity, Hypoeutectic Al-Si Alloys, Porosity, Quantitative Evaluation, Shrinkage Porosity

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