Behaviour Of Cracks In Microalloyed Steel Welded Joint

Numerous are examples of failure and damages of welded joints, despite strict codes regarding the quality. The primary causes are defects in welded structures that arise during production or in service. For safe service of structures produced of high strength steel by welding, properties of welded joints have to be determined. For welded joint constituents (parent metal PM, weld metal WM, heat-affected-zone HAZ) these properties are determined: hardness, impact energy and its parts for crack initiation and propagation, and fracture mechanics parameters, fracture toughness, KIc, and critical J integral, J(Ic),. These parameters can help in evaluation of welded joint safety, and thus of the entire welded structure.