FD&E Total Life T-Sample Residual Stress Analytical Predictions and Measured Results
The SAE Fatigue Design & Evaluation Committee is actively working on a total life project for weldments, in which the welding residual stress is a key contributor to an accurate assessment of fatigue life. Physics-based welding process simulation and various types of residual stress measurement were pursued to provide a sufficiently accurate representation of the residual stress field at the failure location in the fatigue samples. A well-controlled and documented robotic welding process was used for all sample fabrication to provide accurate inputs for the welding simulations. Both destructive (contour method, x-ray diffraction (XRD) with etching) and non-destructive (surface XRD, energy dispersive diffraction (EDD), neutron diffraction(ND)) residual stress measurements were performed on the same or similarly welded samples. The sample is constructed with multiple-pass fillet welds, which induce large gradients in residual stress through the one-inch thickness.