Effect of Mg and Sr Additions on the Microstructure, Mechanical Properties and Reciprocating Wear Characteristics of Hypereutectic Al-14Si Alloy

Abstract:

The explorative attempt to harness new materials that could be utilized for manufacturing products with sophisticated geometry for aerospace and automotive applications necessitate the exploitation of Al-Si-Mg alloy family. Al-14Si alloys which posses 1% Mg exhibits a microstructure that contains primary Si particles, eutectic Si and Mg₂Si in α-Al matrix. With a view to improve the mechanical properties of this alloy, Sr modification was carried out by adding 0.04% Sr to the molten metal. The Mg₂Si phase has high melting temperature, low density, high hardness, low co-efficient of thermal expansion and high elastic modulus. The best results in the microstructure were obtained through a combination of Sr addition and T6 heat treatment which enhances the mechanical properties and wear resistance of the alloy.

• Periodical: Applied Mechanics and Materials (Volumes 592-594)
• Pages: 1296-1299
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.592-594.1296
• Online since: July 2014
• Authors: K. Pratheesh*, M. Ravi, Allesu Kanjirathikal, M.A. Joseph, P. Karrupuswamy
• Keywords: Hypereutectic Al-Si, Microstructure, Modification, Silicon Morphology, Tensile Properties, Wear

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