Total strain-controlled low-cycle fatigue tests and sustained peak low-cycle fatigue tests with load-holding at maximum tension strains were conducted on powder metallurgy (PM) FGH4096 superalloy at 700 ℃. The influence of the dwell time on the hysteresis loops

stress relaxation

cyclic stress response

fatigue life and damage mechanism were discussed. As shown in test results

tensile strain holding reduce fatigue life. PM FGH4096 superalloy exhibits cyclic softening with different dwell time at the total strain range of 0.9%. The saturation phenomenon of holding effect is found when dwell time increases. Stress relaxation and creep deformation occur during the tensile strain holding period. The stress decreases sharply in the first few seconds of the tensile strain holding period and much slowly later. The low-cycle fatigue fracture and sustained peak low-cycle fatigue fracture are composed of fatigue source area

fatigue crack propagation area and instantaneous fracture area. The fatigue source area is located on the specimen surface. No obvious creep fracture characteristics are found in sustained peak low-cycle fatigue fracture and low-cycle fatigue fracture.