Texture Evolution and In Situ Investigation of Recrystallization Behavior in a Hot-Rolled Al-Zn-Mg-Cu-Zr Alloy

By means of characterization techniques such as XRD, TEM, and in situ EBSD, the texture evolution, recrystallization behavior, and their modulation by the Al3Zr phase in hot-rolled Al-Zn-Mg-Cu-Zr alloys with varied homogenization treatments were investigated. Results show that both the single-stage homogenized (SH) alloy and the double-stage homogenized (DH) alloy acquired a typical β-fiber texture after hot rolling, including brass, S, and copper orientations. The DH alloy experienced suppressed recrystallization (a recrystallization fraction of 6.05%) owing to its higher density of Al3Zr precipitates. In contrast, the SH alloy exhibited more significant dissolution and agglomeration of Al3Zr, leading to extensive recrystallization peaking at 78.1%. The primary recrystallization mode was identified as continuous recrystallization, characterized by the growth and coarsening of subgrains. Although dynamically recrystallized (DRx) grains formed during hot rolling could act as potential recrystallization nuclei, most of them exhibited weak growth capability, except the cube-oriented grains. During recrystallization, deformed grains with S orientation tended to transform into cube-oriented grains, while those with brass orientation prefer to convert into Goss-oriented grains. This can be attributed to the presence of highly mobile grain boundaries between these specific orientation pairs. In the DH alloy, subgrain growth and DRx grain consumption during annealing reduced orientation dispersion in deformed grains, promoting marked brass texture strengthening, with its volume fraction reaching 57.7%.