PUNCHING PROCESS FOR PROCESSED MATERIAL

摘要

PROBLEM TO BE SOLVED: To provide a punching method for a work material that can perform punching processing superior in barring performance in a few steps regardless of variation of yield strength of the work material.SOLUTION: The punching method for a work material, which punches a hole to form a nearly circular punched portion in a rolled work material by contacting a wedge-shaped punch to the rolled work material and using a die into which the punch is inserted, performs: a first step of specifying a first direction in which ductility becomes best in the work material; and a second step of setting an angle between the blade edge of the punch and the first direction to 10° or less in a directional vision of punching using the punch and contacting the punch with the work material.