Effect of Tool Surface Finishing on Sheared Surface Characteristics in Shearing of Oxygen-Free Copper

Three types of punch were prepared for sharing the oxygen-free copper sheets with the thickness of 0.5 mm; Normal punch with sharp edge, Lapped punch, and Nitrided-lapped punch. The smooth sheared surface with the smallest fractured area ratio and shear-droop was obtained using the Nitrided-lapped punch. No adhesion of active copper fresh surfaces was detected on the Nitrided-lapped punch surface. The work materials deformed along the smooth punch surface without adhesive wear due to the chemical inertness of Nitrided-lapped punch.