摘要 |
PROBLEM TO BE SOLVED: To prevent a first plate material 2' from being flawed or cracked due to stress concentration in part of the first plate material 2' which overlaps with the outer edge of a second plate material 3', in a method for forming a two-ply product wherein the second plate material 3' is formed without being bound while the first plate material 2' is overhang-formed, with the outer edge of the first plate material 2' being bound, by using a blank material 1' which is produced by laminating the first plate material 2' which is a base product with the second plate material 3' which is a platy part. SOLUTION: The opposite surface of the second plate material 3' to the surface of the second plate material 3' where burrs 3'a occur in the shearing process of the second plate material is laminated with the first plate material 2'. There occurs sagging 3'b on the outer edge of the opposite surface to the surface of the second plate material 3' where the burrs occur. This sagging alleviates the stress concentration against the first plate material 2'.
|