Fatigue characterization by heat source reconstruction under continuously varying stress amplitude

Abstract

Self-heating measurements using thermography have proven to be an effective means of rapidly assessing the fatigue response of materials. The paper validates the use of a post-processing technique, called “heat source” reconstruction, in the case of cyclic loading with continuously varying stress amplitudes, offering significant advantages over classical self-heating approaches: considerably reduced test time (some minutes compared to a few hours); continuous measurement of mechanical dissipation versus stress amplitude; higher maximum stress amplitude achieved due to slower accumulation of fatigue damage during testing. The approach was validated by comparison with the classical procedure, and opens new perspectives for fatigue characterization.