Effect of Brine Quenchants and Precipitation Hardening on the Mechanical Properties of Aluminium Alloy (Aa6061)

This article demonstrates the influence of varying quenchants and precipitation hardening on the mechanical characteristics of Aluminium alloy 6061. Three samples were chosen for the impact test. Solution treatment was performed at 540°C for 2 hours and then cooled at three different brine concentrations (3%, 7%, and 10%). As a result, brine (3%) had the best result with the lowest rate of shock absorption (18.31 J); therefore, for this study, brine (3%) was selected as the quenching medium. All specimens for the tensile, impact, and hardness tests were solution-treated at 540 °C for two hours, subsequently cooled in Brin 3% to ambient temperature, and artificially aged at 180 °C. for 1,2, and 4 hours, at 195°C for 1,2, and 4 hours, and at 210°C for 1,2, and 4 hours. Due to the formation of finely dispersed grains, notable increases in strength and hardness were seen alongside a decrease in ductility. The overall best result achieved was by precipitation hardening at 210°C for 2 hours, which increased the ultimate tensile strength to 340.3 MPa compared to the as- received and annealed samples values which were 260 MPa and 152.02 MPa respectively. In addition, Hardness value increased from annealed condition (18.23 HRB) to (44.14 HRB)