Aging Treatment and Mechanical Behavior of a Nanodispersed Al-16Si-5Fe-1Cu-0.5Mg-0.9Zr Alloy

摘要

The aging behavior and tensile properties were investigated by using Al-16Si-5Fe-1Cu-0.5Mg-0.9Zr alloy fabricated by a powder metallurgical route through the hot extrusion of rapidly solidified powder. The extruded materials were solutionized at 768K for 20min and subsequently aged at 413 ～ 453K for 10 ～ 480min. The microstructure of the peak-aged sample involved the precipitates of a nano-sized (20 ～ 100nm) Q phase (Al-Si-Fe-Cu base intermetallic compound). The yield and ultimate tensile strength of the peak-aged sample showed higher values up to 473K compared to the as-extruded one. A filament-like phase containing Cu and Mg was observed in the fracture surface of the as-extruded sample deformed at 793K. In contrast, such a phase was invisible on the peak-aged sample. It was considered that the filament-like phase contributes to enhance the ductility at elevated temperature.