Fatigue life prediction on ni-base thermal solar receiver tubes

Kurzfassung

Solar receivers for tower type Solar Thermal Power Plants are subjected to complex thermo-mechanical loads including fast and severe thermo-mechanical cycles. The material temperatures can reach more than 800 °C and fall to room temperature very quickly. In order to predict the fatigue life of a receiver design, receiver tubes made of Alloy 625 with a wall thickness of 0.5 mm were tested in isothermal and thermo-cyclic experiments. The number of cycles to failure was in the range of 100 to 100,000. A thermo-mechanical fatigue life prediction model was set up. The model is based on the cyclic deformation of the material and the damage caused by the growth of fatigue micro cracks. The model reasonably predicts the experimental results.