Fatigue properties of electron beam welded joints of Nickelbase superalloy

The microstructure,high and low cycle fatigue properties of GH4169 electron beam (EB) welded joints were investigated. The results show that the EB weld of GH4169 alloy consisted of dendrite structures with the developed dendrite and secondary dendrite. The heat-affected zone (HAZ) and base metal showed also dendrite structure. The low cycle fatigue properties of joints were not lower than those of the base metal. With strain amplitude reduced,the low cycle fatigue life of joints became higher than that of the base metal at the same strain amplitude. The median high cycle fatigue strength of joints was about 80 MPa higher than that of the base metal.