Investigating the Influence of Casting Parameters on the Mechanical and Microstructural Characteristics of Grade Al6063 Alloy

摘要

Influence of casting parameters on the mechanical properties and microstructure of alloys is gaining more prominent research concerns. The main aim o f this work is to investigate the effect of three main casting parameters (Pouring temperature, pouring speed and pouring height) o n the mechanical and microstructural characteristics of Al6063. The Al6063 obtained in billet form, was processed into cylindrical shape of length 20 cm and diameter 2 cm by casting. Fifteen cast samples were obtained at varying pouring temperatures, pouring speeds and pouring heights. Tensile, impact and hardness tests were performed. The samples were thereafter examined using optical metallurgical microscope. Results showed that enhanced mechanical and microstructural characteristics were obtained at the pouring temperature of 730 o C, pouring speed of 1.75 cm/s, and at pouring height of 15 cm relative to the as-received Al6063 aluminium alloy. This can be attributed to the effect of grain refinement during recrystallization and solidification as there was increase in the total grain boundary area capable of impeding to certain extent dislocation motion. In addition, it can be inferred that there exist also grain growth occurrences and the emergence of precipitates Mg 2 Si in the alloy and this perhaps was responsible for the observed considerable increase in hardness.