最弱链模型估算局部脆性区尺寸对焊接热影响区断裂韧度的影响

EFFECTS OF LOCAL BRITTLE ZONE ON THE HAZ FRACTURE TOUGHNESS EVALUATED USING THE WEAKEST LINK MODEL

从最弱链模型的物理本质出发，探讨了影响焊接热影响区脆性断裂的主要因素。在一定的断裂韧度前提下，随着局部脆性区尺寸的增加，焊接热影响区的脆断概率增加。当断裂概率一定时，局部脆性区尺寸增加，焊接热影响区断裂韧度下降。

In this paper,the brittle fracture probability of weldments and the fracture toughness of heat affected zone (HAZ) were investigated according to the principle of the weakest link theory. At a certain fracture toughness value, fracture probability of weldments increases with increase of the local brittle zone size. On the other hand, fracture toughness of HAZ decreases as increasing the local brittle zone size. Effects of parameters in the weakest link model on the fracture toughness value distribution and probability density function were discussed.