Effect of Heat Treatment on Tensile Strength of Direct Recycled Aluminium Alloy (AA6061)

Abstract

Products by solid-state recycling of aluminum chips in hot extrusion process were controlled by temperature related parameters using preheating temperature 450 °C, 500 °C, and 550 °C for 1 hr, 2 hr, and 3 hr preheating time. By using Design of Experiments (DOE), the results found that the preheating temperature is more important to be controlled rather than the preheating time and increasing of temperature led to the high tensile strength. The profile extruded at 550 °C with 3 hr duration had gained the optimum case to get the maximum tensile strength. For the optimum case, heat treatment was carried out using quenching temperature at 530 oC for 2 h and aging process at 175 oC for 4 h. The tensile strength of extrudes specimen was improved significantly compared to those of non-treated specimen.