Ageing Characteristics of Sand Cast Al-Mg-Si (6063) Alloy

The effect of variation of ageing temperature and soaking time at the ageing temperature mechanical properties of aluminium 6063 alloy was investigated. Various samples of the alloy in the as-cast condition were produced, homogenized at 560℃ held at the temperature for 2hrs, and cooled in the furnace. They were solution treated at 440℃ for 10minutes and quench in water, aged at/soaked for 125℃/3Hrs, 125℃/4Hrs, 125℃/5Hrs, 175℃/3Hrs, 175℃/4Hrs, 175℃/5Hrs, 200℃/3Hrs, 200℃/4Hrs, 200℃/5Hrs, and 225℃/3Hrs, 225℃/4Hrs and 225℃/5Hrs. Tensile and impact test were carried out on the alloy standard samples. It was observed that the Optimum tensile strength is observed in the sample aged at 175℃ held for 5hrs, optimum ductility is observed in sample aged at 125℃, held for 4hrs, Optimum toughness is observed in sample aged at 225℃, held 5hrs, closely followed by that of the sample aged at the same temperature, held for 3hrs. From the economic point of view the optimum parameter for obtaining a structural material of the optimum combination of mechanical properties from the sample is ageing temperature of 225℃ and soaking time of 3hrs.