| 摘要 |
PROBLEM TO BE SOLVED: To provide a shearing/forming method for a material to be worked by which the stretch-flanging property in a sheared end part is improved stably while suppressing the increase of production cost. SOLUTION: In the shearing/forming method for the material 1 to be worked, by which the material 1 of a predetermined shape to be subjected to stretch-flanging machining is formed by shearing using a punch 11 and a die 13, when applying the stretch-flanging machining to the sheared end part 33 of the material 1, a bead 43 is imparted to the material 1 so that tensile stress of 50-400 MPa is added to the part to be the risky part 31 of cracking in the stretch-flanging and the material 1 is sheared as it is with reverse metal plate press 17 and the punch 11 or with a blank holder 15 and the die 13 after specifying the predetermined position of the sheared end part 33 having the risk of cracking as the risky part 31 of cracking in the stretch-flanging by experiences or numerical calculation. COPYRIGHT: (C)2010,JPO&INPIT |
