Microtextural evolution of different TRC AA8006 alloy sections with homogenization

Grain microtexture evolution in twin-roll cast AA8006 alloy sheets subjected to different treatments was investigated using electron backscatter diffraction. The textures of rolling-transverse and normal-transverse sections were characterized in original as-cast twin-roll casting and cold-rolled samples as well as samples homogenized at 500℃ for 8 h and at 580℃ for 4 h. It is found that grains on both the rolling-transverse and normal-transverse sections of cold-rolled samples are made finer by rolling deformation and coarsened after homogenization. Annealing temperature has a stronger effect on the microstructural evolution than annealing time. The grain growth direction is parallel to the normal-transverse section, while grain deformation is more stable on the rolling direction than on the normal direction. The rolling orientations display more obvious anisotropy on the normal-transverse sections than on the rolling-transverse sections. Grain recrystallization and growth occur much easier on the normal-transverse section than on the rolling-transverse section for samples homogenized at 500℃ for 8 h. A special misorientation relationship between cold deformation texture, such as S orientation 123<634> and cube orientation <110>‖X_axiscubic, and recrystallization texture after homogenization, such as R orientation 124<211> and P orientation 011<122>, is observed.