Microstructure Evolution and Mechanical Properties of the T6 Heat Treated AA6063 Alloy Produced by Squeeze Casting

Abstract

The influence of T6 heat treatment on the microstructure, hardness and tensile properties of cast AA6063 aluminum alloy was investigated as a function of squeeze casting pressure. The specimens elaborated were solution treated at 500°C for 8 hours and then were subjected to aging at 140°C. Various test techniques, including optical microscopy, scanning electron microscope, X-ray diffraction, tensile tests, and hardness were used to examine the effect of this alloy produced by the gravity and squeeze casting processes. The experimental results showed that Mg₂Si and Al₁₅Si₂(FeMn)₃ were the primary particles observed in the α-Al matrix. The effect of precipitation on the mechanical properties was investigated. The changes in mechanical properties were correlated with changes in microstructure evolution and Mg–Si precipitation. Furthermore, hardness and tensile properties increased with both heat treatment and squeeze pressure.