Evolution of microstructures and textures of 7050 Al alloy hot-rolled plate during staged solution heat-treatments

The evolution of the microstructures and textures of 7050 Al alloy hot-rolled plates were studied during a series of staged solution heat-treatments (S-SHT). The results show that the texture type in the specimens after various S-SHT processes is similar to that of the as hot-rolled for solution temperatures up to 490 °C. The grain orientations are assembled to typical β-fiber and α-fiber, together with some {0 0 1} 〈1 0 0〉 texture. The orientation densities of {1 2 4} 〈2 1 1〉 and {1 1 2} 〈1 1 1〉 textures in the S-SHT specimens are higher than that of the as hot-rolled; however, they decrease with increasing solution temperature because of recovery and continuous recrystallization. At 475 °C, the specimens contain Al2CuMg and Al7Cu2Fe particles, but only Al7Cu2Fe particles exist at 490 °C. The S-SHT described in this paper improves the mechanical properties of 7050 Al alloy plate, in particular, the elongation to failure, which increases from 8.8% to 14.2%.