| 摘要 |
Disclosed is a method of predicting lives of dies for plastic processing of metals, typically, forging dies, to enable improved die design by predicting an important factor, low cycle fatigue life FL (shot number possible until the die lives end). The method is characterized in that the low cycle damage value "Dc" defined by the formula: Dc=Ã eq /(YS× softening rate), wherein, Ã eq is Von Misese's equivalent stress, YS is yield stress (including both of those at tension and compression), and that the following formula is introduced: FL = C 1 × exp(C 2 × Dc C3 ), wherein, FL is shot number until the die fracture, and C 1 , C 2 and C 3 are constants depending on the material used, so as to presume the possible shot number of the die. |
