Abstract
A numerical investigation for a crack located in the boundary between the weld metal and the heat affected zone (HAZ) of a welded joint is presented. Three-dimensional finite element analyses are performed on a center cracked panel (CCP) subjected to tension and single edge notch bend (SENB) specimens. The numerical results show that the stresses that develop in the HAZ region of the overmatched welded joint are more intense than those in the undermatch and evenmatch cases. It is noted that highly stressed near-tip zones are detrimental to fracture resistance of HAZ regions containing local brittle zones. A discussion also follows on the significance of weld strength overmatch on fracture behavior of HAZ-notched welded joints, which is based on the local approach. The analyses indicate that the relative load-carrying capacity of a overmatched joint may be reduced, especially in the case of the high constrained deep notch bend specimen. Such features may be particularly deleterious to cleavage fracture resistance of welded joints containing cracks close to the HAZ region.