Experimental investigation on fatigue crack growth of directional solidified superalloy with single hole

In order to study the fatigue crack growth of directional solidified superalloy with single hole, the fatigue crack growth test of DZ125 was carried out under different stress levels. The fracture morphology of the specimens were analyzed by field emission scanning electron microscope, and the relationship between stress and life was fitted. It is found that the stress concentration around the hole and the defects lead to the crack initiation near the maximum principal stress point. The da/dN - Δ K satisfies Paris formula well. (paper)