Abstract:The effects of total strain range and dwell time on low cycle fatigue life of C-276 alloy at 650 °C were investigated. The total strain range controlled fatigue tests were performed at total strains of 0.3%, 0.35%, 0.4%, 0.45% and 0.5% with dwell time of 0, 30 and 60 s respectively. The fracture characteristics were observed by SEM. Results show that the fatigue life significantly decreases with increasing the total strain range for the fixed dwell time due to the enhanced fatigue crack-growth-rate. The effect of dwell time on the fatigue life is dependent on the introduced total strain range. In lower total strain range of 0.35%~0.4%, the fatigue life is decreased by introducing dwell time, which is obviously caused by the coeffect of the enhanced fatigue crack-growth-rate and the presence of some microcracks and cavities. In higher total strain range of 0.45%~0.5%, the fatigue life is increased by introducing dwell time due to the closed microcracks and cavities