Study on mechanical property, formability and corrosion resistance of Al–Mn and Al–Mg photovoltaic cabinets before and after forming

Abstract

To develop large-sized cabinet aluminum alloys with lower production costs and superior formability, mechanical property as well as corrosion resistance, the representative 3104 Al–Mn and 5052 Al–Mg alloy rolling sheets along with their formed cabinets were studied to investigate the relationship between microstructure characteristics and performances. The recrystallization cube texture and fewer second phases in the 5052 alloy causes the uniform formation of dislocations, corresponding to the better formability. The ultimate tensile strength, yield strength and elongation along rolling direction reach 183.3 MPa, 87.7 MPa and 28.7%, which is mainly ascribed to the finer grain size and solution strengthening of Mg atoms. For the 5052 cabinet, the microstructure is composed of uniform deformed grains with high-density dislocations, further enhancing the hardness and strength. The better resistance to uniform and pitting corrosion without sensitivity to intergranular corrosion can also be obtained, which is attributed to the lower and more uniform local strain as well as the fewer Fe-containing second phase compared to the 3104 alloy. After rectangular drawing, the local strain increases and the finer grains with high-density dislocations can facilitate the dynamic formation and self-healing mechanisms of the oxide film so that further enhance the corrosion resistance.