Font Size: 

The differences in mechanical properties amongst different welded joints’regions obviously affect the strain distribution around the crack tip during the fracture testand, hence, influence the toughness value. The strength mis-match and width of weldedjoint have an effect on the stress-strain distribution in the vicinity of the crack tip. Both cancontribute to a higher constraint in the weld metal. It was found that the width of thewelded joint as constraint parameter has an effect on the limit load, maximum load andachieved fracture toughness values of a welded joint. In the case of strength overmatchedwelded joints, the limit and maximum loads increase with constraint (welded joint width)decrease. On the contrary, in the case of strength under-match welded joints the limit andmaximum loads decrease and the constraint (welded joint width) decreases.