2019 Volume 60 Issue 706 Pages 327-332
A large roll-over is formed on the cut edge around the convex portion of the blanked component and it causes some functional problems in gear products. This study is aimed at revealing the mechanism of roll-over formation and identifying the parameters affecting the formation. Through experiments using annealed pure aluminum, the increase in the height of roll-over dp as in figures was observed to be independent of the punch-die clearance for a small convex-tip radius, whereas the roll-over height dp increased only with large clearances for a large tip radius. Numerical results agreed well with the experimental results and suggested contributions of indentation deformation and radial material flow occurring at the convex tip to the increase in roll-over height dp .