In-situ EBSD observation of texture evolution and lattice rotation behavior in shear deformation of thin-walled aluminum alloy tubes

As shear stress plays a significant role in the deformation of tubular parts with complex shapes, investigation of the microstructue evolution of tubes under the shear stress state is beneficial to understanding the shear deformation mechanism and promoting the prediction accuracy of numerical simulation. In this paper, the shear experiments were conducted on thin-walled 5052 aluminum alloy tubes. The texture evolution and lattice rotation behavior of the tube during shear deformation were studied using in-situ electron back scatter diffraction (EBSD) technology. It is shown that the initial Cube texture remains stable, while a new Rot. Copper texture is formed in the shear deformation zone. The grains with the orientation of parallel to the axial direction (AD) tend to stabilize, while several low-angle grain boundaries (LAGBs) are formed inside the grains with unstable initial orientations. Notably, the orientations of adjacent grains are more similar after shear deformation, and the high-angle grain boundaries (HAGBs) gradually transform to LAGBs showing the characteristics of polycrystalline cooperative deformation. By analyzing the lattice rotation mechanism under shear stress, it is found that the shear stress promotes the lattice rotation to a stable orientation parallel to the direction of the shear stress. This research provides theoretical guidance for predicting the forming of tubular parts with complex shapes.