Microstructure, texture and property of extruded 7N01 aluminum alloy plates

The effect of natural and artificial aging treatment on tensile properties and corrosion resistance and on the microstructure and texture was investigated respectively by means of mechanical test and of observation with OM, SEM and TEM etc for aluminum alloy 7N01 plates extruded with different extrusion ratio (λ=36 and16). The results show that after natural and artificial aging there exist significant difference in the microstructure and mechanical property for the above mentioned 7N01 plates. There exist a large number of tiny recrystallized grains in the plate with higher-extrusion ratio, while coarse subgrain structures in the plate with lower-extrusion ratio; the former one possesses higher tensile strength and yield strength rather that the later one; while the precipitates at grain boundaries in the former one seemed much discrete with each other. Meanwhile, for the plates extruded with the same extrusion ratio both the tensile strength and elongation were decreased after artificial aging in comparison to those naturally aged, i.e. tensile strength was about 5.8% lower, however the yield strength increased reversely by about 25%; the precipitates at boundaries seemed also much discrete with each other after artificial aging, and thereby exhibited better corrosion resistance.