Fracture toughness of welded joints with crack in transverse hard layer

In the paper welded joints with a crack in transverse overmatched weld or HAZ were simplified into a model in which a transverse hard layer contains a crack parallel to the interfaces. Effects of mechanical heterogeneity on fracture toughness and crack deviation angle of the joints were investigated by experiment. Meanwhile, moire method was used to observe the displacement distribution in the vicinity of the crack surfaces.