On the Role of Copper and Cooling Rates on the Microstructure, Defect Formations and Mechanical Properties of Al-Si-Mg Alloys

Salem Seifeddine, Emma Sjölander, Toni Bogdanoff

Materials and Manufacturing-Casting, Department of Mechanical Engineering, School of Engineering, J?nk?ping University, J?nk?ping, Sweden..

DOI: 10.4236/msa.2013.43020                

Abstract

This paper aims to assess the role of Cu on Al-Si-Mg alloys, in a range of 0 - 5 wt%, qualitatively on microstructure, defect formation, in terms of porosity, and strength in the as-cast conditions. The ternary system of Al-Si-Mg, using the A356 alloy as a base material, were cast using the gradient solidification technique; applying three different solidification rates to produce directional solidified samples with a variety of microstructure coarsenesses. Microstructural observations reveal that as the Cu levels in the alloys are increased, the amounts of intermetallic compounds as well as the Cu concentration in the α-Al matrix are increased. Furthermore, the level of porosity is unaffected and the tensile strength is improved at the expense of ductility.

Keywords

Aluminium-Silicon Alloys; Microstructure; Mechanical Properties; Gradient Solidification

Conflicts of Interest

The authors declare no conflicts of interest.

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