A new application of the infrared thermography for fatigue evaluation and damage assessment

A new method, based on the infrared thermography, was proposed and applied to rapidly determine the fatigue behavior of Q235 steel. The temperature evolution due to localized microplasticity was considered as the fatigue damage indicator, and good predictions were confirmed between the predicted values and the traditional values. The temperature patterns of the hot-spot zone on the specimen surface were tightly linked with the physical evolution of the fatigue damage in order to identify the damage status for safety evaluation. Based on the limiting energy theory, an energetic damage model was established to predict the residual fatigue life.

► A new application of the lock-in infrared thermography was applied to predict the fatigue behavior of Q235 steel.
► The fatigue damage status was evaluated by the temperature variations on the hot-spot zone.
► An energetic damage model was advanced to predict the residual fatigue life.