Investigation of the Effects of Varying Copper Concentrations on the Mechanical Properties of Aluminium

Abstract

The effects of varying Cu concentrations on the mechanical properties of pure Al has been investigated. Seven samples of Al-Cu alloy systems with copper concentrations 0.0%,2.5%,5.0%,7.5%,10.0%,12.5% and 15.0% by wt% labelled A, B,C,D,E, F, and G respectively were fabricated and subjected to hardness, tensile strength, yield strength, and ductility tests, optical microstructural examinations were carried out on each of the samples. Results showed that the tensile strength and hardness of the Al alloy samples increased with increase in copper concentration for all the samples, while the yield strength increased progressively from samples A to E and remained constant for samples E to G. However, the ductility of the samples decreased with increase in copper concentrations. The microstructural examinations of the alloy samples revealed a decrease in the grain boundaries of Al-Cu alloy samples with an increase in copper concentrations. This resulted to an increase in the hardness, tensile strength, yield strength, and decrease in ductility as copper concentration increased. It can be concluded, that the mechanical properties of Al can be altered with a systematic increase in copper concentration within the experimented samples.

Keywords

• Aluminium
• Copper
• Mechanical Properties
• Grain Boundaries
• Aluminium-copper alloy