Residual stress measurements and analysis by destructive and non-destructive techniques

This investigation is focused on the evaluation of residual stresses resulting from cold deformation and welding in candidate target structural materials such as martensitic Alloys EP-823 and HT-9, and austenitic Type 304L stainless steel (SS). Measurements of residual stresses were performed by both destructive and nondestructive techniques including ring-core (RC), neutron diffraction (ND) and positron annihilation spectroscopy (PAS). The results obtained by the PAS method indicate that the residual stresses in the cold-worked specimens were significantly enhanced with increased level of cold reduction. Residual stress measurements by the RC method on welded specimens consisting of similar materials revealed tensile stresses on both sides. The welded specimens consisting of similar and dissimilar materials showed compressive residual stresses on one side (Alloy EP-823) and tensile stresses on the other side (Type 304L SS). In general, a good agreement in the measured residual stresses was observed based on their comparisons on different configurations of testing specimens using state-of-the art experimental techniques