Effect of Cooling Rate on Material Properties in Homogenization Heat Treatment of 6060 Aluminum Alloy

Abstract

An important alloy family utilized in the extrusion sector is the 6xxx series of aluminum alloys, which can also be aged through heat treatment. Because of its excellent extrudability, it is easily formable. Before extrusion, formable aluminum alloys are typically heated through homogenization. With the homogenization process applied to the material, it is ensured that the product surface is clean and the microstructure that determines the extrusion speed is obtained with the controlled cooling applied after homogenization. In this study, homogenization heat treatment was carried out in continuous type homogenization furnaces of AA-6060 series Al billet produced with direct chill (DC) casting. In the cooling section, different cooling rates were obtained by changing the speeds of the fans and the effect of the cooling rate on the material properties were examined. According to X-ray diffraction (XRD) results, β-AlFeSi, α-AlFeSi and Mg2Si phases were observed in the alloys. The needle-shaped β-AlFeSi phase seen at the grain boundaries of the casting sample was observed by scanning electron microscope (SEM) and optic microscope (OM), where homogeneously heat-treated samples transformed into spherical form α-AlFeSi at the grain boundaries. Although the cooling rates did not have a significant and significant effect on the microstructure in homogenization, the saving obtained from the total electricity consumption of the turbo fans was 29.6%

Keywords

• aluminium alloys
• homogenisation
• microstructure
• material properties