Design of pearl shell-inspired biomimetic textured rollers and their tribological performance during roller hemming

The wear condition of the roller surface on the roll-forming end effector significantly affects the quality of automotive body molds and the service life of the corresponding equipment. To address these issues, this study proposes a biomimetic roller design strategy based on the microstructure of the pearl shell surface. A corresponding texture-morphology mapping model was established, followed by multi-scale mechanical and tribological performance analysis. Simulation results indicate that, under the same depth-to-width ratio conditions, the roller with arcuate grooves exhibits the lowest friction energy loss and the highest principal stress compared to rollers with vertical and rhombic grooves. Friction wear tests further validate the advantages of this structure, showing significantly lower coefficients of friction, wear depth, and wear mass than those of rollers with vertical and rhombic textures, demonstrating superior wear resistance. Based on this, the depth-to-width ratio structure of the arcuate striped roller was further optimized using the golden section method, determines a global optimal depth-to-width ratio of 0.775. Compared to ordinary rollers, the maximum principal stress along the rolling direction increased by 18.3% for the optimized roller, while rolling friction energy decreased by 70.28%. This study demonstrates that biomimetic textures can significantly improve the surface stress distribution and tribological performance of rollers, provide theoretical support and innovative solutions for enhancing the stability of automotive body manufacturing processes and the reliability of intelligent devices.