| 摘要 |
PURPOSE: To provide a method for quenching a die, by which a bending die having very small strain and simple manufacturing process and improving the hardness more than that of the conventional die and the safety without damaging the toughness is obtd. and cooling time and preheating time in a tempering after the quenching are shortened and can be adjusted and further, the normal quench can be executed, and a device therefor. CONSTITUTION: Since a quenched hardening layer 5 of <=1.0mm is formed at an edge part 3 of the bending die 1, the strain becomes very small and the manufacturing process of the die is simplified. Further, the hardness is improved more than that of the conventional die and the safety without damaging the toughness is improved. Further, the quenched hardening layer only to at least tip part 3A in the edge part 3 of the punch 1 and the quenched hardening layer to both shoulder parts in the edge part of the die are formed so as not to quench-harden the bottom part. Further, the method for quenching various kinds of the dies forming this quenched hardening layer and device therefor are provided. |
