| 摘要 |
PROBLEM TO BE SOLVED: To provide a die for drawing capable of shaping a trihedral corner at an angle closest to orthogonal to high sidewall portions.SOLUTION: A die (1) for drawing includes a punch (10) for inserting a material plate so as to form an inner shape of a polygonal container, a die (20) having a polygonal hole (21) which allows the material plate inserted by the punch (10) to enter, a blank holder (30) having a polygonal hole (31) for the insertion of the punch (10) and holding the material plate at the circumference of the hole (21) of the die (20). In a clamping surface of at least one of the die (20) and the blank holder (30), regions facing linear portions of the polygonal hole include portions whose surface roughness is smaller than that of regions facing corner portions. |
