| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for forming a cylindrical member by forge- heading with which the cylindrical member having sufficiently high strength even near the end surface can be obtained without changing constituting material (kind of metal, kind of steel) in the cylindrical member or applying a quenching treatment. SOLUTION: This forming method of the cylindrical member is performed by forge-heading is performed, by which after inserting a solid blank into a tool die hole, a punching pin is punched from the end surface of the solid blank to form the cylindrical member. Before punching the punching pin, a first step working for giving the strain near the end surface of the solid blank (the working applying a deep drawing into a range from the end surface to 5-50% of the whole length of the blank, or the working pushing the pin for pushing to the depth of 5-50% of the whole length of the blank from the end surface of the blank, or the working compressing near the end surface of the solid blank), is peculiarly applied.
|
