Fatigue assessment in welded joints based on geometrical variations measured by laser scanning

In the current study a method to determine the location of fracture initiation for non-load carrying fillet welds based on continuous geometry measurements is proposed. Measurements and weld quality evaluation were carried out on welded specimens using the Winteria® software qWeld. One hundred nineteen specimens were produced, scanned, and fatigue tested until failure. The fracture surfaces have been investigated in order to find the location(s) for most probable point(s) of initiation. These data were then used to fit the proposed model parameters used to predict the point of initiation. Local weld geometry measurements were extracted from the predicted fracture initiation location(s) to analyse the correlation between local weld geometry and fatigue life. It was observed that fatigue life and leg length were positively correlated and that strong correlations exist between the individual geometrical parameters with regard to location of the fatigue crack initiation.