TITLE:
On the Role of Copper and Cooling Rates on the Microstructure, Defect Formations and Mechanical Properties of Al-Si-Mg Alloys
AUTHORS:
Salem Seifeddine, Emma Sjölander, Toni Bogdanoff
KEYWORDS:
Aluminium-Silicon Alloys; Microstructure; Mechanical Properties; Gradient Solidification
JOURNAL NAME:
Materials Sciences and Applications,
Vol.4 No.3,
March
29,
2013
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.