Abstract:Analyzing the texture evolution and room-temperature formability of magnesium-manganese alloy thin sheets during warm rolling is of great significance for the development of high-performance magnesium alloy industrial materials. In this study, magnesium-manganese alloy sheets formed by synchronous rolling technology were subjected to large reduction asynchronous warm rolling. Starting from the mechanism of texture weakening in magnesium alloys, a finite element constitutive model of magnesium-manganese alloy was constructed based on the crystal plasticity theory before and after rolling. The tensile, cupping, and rigid die bulging tests were conducted to discuss the specific effects of the above rolling methods on the mechanical and formability properties of magnesium alloy sheets. It was found that there were no significant changes in the texture anisotropy in all directions before and after rolling, but the texture distribution changed significantly, and some grains rotated obviously in the ND direction. The pole density of the basal texture of the initial thin sheet was 29.49mud, while that after rolling was 15.57mud. The peak value of the pole density of the basal texture decreased, and the intensity distribution became more dispersed, indicating that the basal texture of the sheet weakened. The tensile strength of the asynchronous warm rolled sheet was up to 253.9MPa, and the maximum elongation was 10.9%. In a room-temperature environment, the deformation amplitude of the sheet was relatively small, and the maximum cupping depth could reach 2.7mm. The forming limit diagram (FLD) of the warm rolled sheet was drawn through the rigid die bulging experiment. The rigid die bulging experiment was simulated by the finite element analysis method, and the simulation data were compared with the numerical simulation FLD. The results showed that the two were highly consistent in the forming limit. Asynchronous warm rolling weakens the texture by the rotation and recrystallization of grains during sheet deformation, thereby improving the formability of the sheet, providing a possibility for the development of high-performance magnesium alloy thin sheets and even foils.
