Thermal transient test of thermal stress mitigation model 1; vol.1 thermal transient test and crack observasion

not registered

This report describes the result of thermal creep-fatigue test conducted at the Thermal Transient Test Facility for Structures. The model, named 'Thermal stress mitigation model 1', is subjected to cyclic thermal transient of 250 C-620C by sodium. The cycle time of one thermal transient is 2hrs, on which 250 C sodium flows into the model in 40 min and-620C sodium on 80 min. The model has six portions to be tested until failure by creep-fatigue, namely two nozzles, slitted cilinder, skirt structure, and four sorts of weldment. The test was successfuly performed, and we observed expected creep-fatigue crackings at all portions of interest. The temperature data and failure data were obtained for subsequent thermal stress analysis and fracture mechanics analysis. Also ultrasonic examination during the test was effective for identification of crack initiation an the hair crack stage.