Microstructure of Al-17wt.%Si Alloy after Overheating and CuP Master Alloy Modification

Abstract:

In the dissertation the influence of overheating of around 250°C above T_liq and modification with phosphorus (CuP10 master alloy) on the microstructure of AlSi17Cu5 cast alloy has been shown. Substantial overheating above T_liq temperature of the alloy, causes complete dissolving of the β (Si) phase. In the liquid alloy, multiple areas are being created of different dissolved silicon content, where, as in the result of the overheating, the homogeneous nucleuses are being partially created. After modification with phosphorus, in liquid alloy, additional heterogenic nucleuses (AlP) of primary silicon crystals are being created. In the close neighborhood of these micro-areas, places depleted of silicon appears, where pre-eutectic α (Al, Me) dendrites crystallize.

• Periodical: Solid State Phenomena (Volume 229)
• Pages: 11-16
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.229.11
• Online since: April 2015
• Authors: Jaroslaw Piątkowski*, Piotr Kamiński
• Keywords: Hypereutectic Al-Si Alloy, Microstructure, Modification CuP Alloy, Overheating Degree

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