Springback Behavior and Stroke-Based Compensation Strategy for Roll-Based Bending of High-Strength Aluminum Extrusions

High-strength aluminum tubular extrusions are being increasingly used in lightweight automotive structures; however, the significant springback caused by elastic recovery after bending compromises geometric accuracy. In roll-based bending processes, springback behavior is affected by multiple process parameters, which necessitates a systematic investigation and a simulation-based springback compensation approach. In this study, the springback behavior of high-strength aluminum tubular extrusions subjected to roll-based bending was investigated via finite-element analysis. The effects of feeding displacement, roller rotational speed, and internal mandrel application on springback were comparatively evaluated. Springback was quantitatively assessed based on the displacement and angular deviation after unloading, and the influence of each process parameter was analyzed. Based on the results, variations in roller rotational speed had a negligible effect on springback, whereas feeding displacement was identified as the dominant governing factor under all investigated conditions. Although internal mandrel application reduced stress levels and mitigated wrinkle formation, the overall springback tendency remained dependent on feeding displacement. Based on these findings, a simulation-based stroke compensation approach was proposed, and a compensation window satisfying the target curvature radius of R = 150 mm was numerically identified under the investigated finite-element conditions.