Using magnesium alloy plates instead of high-strength steel and titanium alloys in roll-formed parts significantly improves the lightweight, damping, and heat dissipation properties of automotive components. This paper employs finite element simulation combined with experimental methods to perform single-pass roll bending of AZ31B magnesium alloy plates at angles of 0°-15°, 0°-25°, and 0°-35°. Measured the springback angle and microhardness at the bends, and used optical microscopy (OM) and electron back scatter diffraction (EBSD) to analyze the microstructural characteristics, texture, and orientation evolution at the bend during the roll bending process. The results indicate that during roll bending, the inner bend area has significantly more twins than the outer area, with more pronounced grain refinement on the inner side. {10−12} tensile twins mainly coordinate plastic deformation, with some {10−12}-{10−12} tensile twin variants present. The inner bend area's texture shifts from ND to TD direction, strengthening the TD direction texture, while the outer area retains typical rolling texture. The prismatic slip in the inner region of the bend changes from hard to soft orientation. The inner region is mainly coordinated plastic deformation by prismatic slip, while the outer region is mainly coordinated by basal slip. As single-pass roll bending angles increase, the increase in twin boundaries and low-angle grain boundaries (LAGBs) significantly reduces the springback angle. Additionally, grain refinement and increased geometric necessary dislocation density lead to higher microhardness.
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