Use of infrared thermography to model the effective stress ratio effect on fatigue crack growth in welded T-joints

Abstract

Welded joints constitute critical components in the high-cycle fatigue dimensioning of naval structures. In particular, the local geometry of the weld toe as well as the welding process induced residual stress strongly impact the fatigue properties. In that regard, such factors must be considered in a dedicated fatigue life forecast model, identified via an adapted experimental protocol. On the basis of X-ray stress analysis and in-situ crack growth monitoring by thermoelastic stress analysis, the present study introduces a linear elastic fracture mechanics model that considers the initial residual stress field in the vicinity of the weld toe.