THERMOGRAPHY DETECTION OF LOW-CYCLE AND HIGH-CYCLE FATIGUE BEHAVIOR OF REACTOR PRESSURE VESSEL (RPV) STEELS

摘要

An infrared (IR) thermography technique, as a nondestructive evaluation technique, was applied to investigate the fatigue damage of reactor pressure vessel (RPV) steels during 0.5 Hz and 20 Hz fatigue testing. Specimen temperature oscillation during low-cycle and high-cycle fatigue is discussed. The relationship among the temperature, stress-strain state, and fatigue behavior is investigated. Both thermodynamics and heat-transfer theories are applied to model the observed temperature variation during fatigue. Fatigue life prediction using the measured specimen temperature has been conducted and compared with the experimental results.