Residual Stress in Welding and Additive Manufacturing: Measurement, and Mitigation

This presentation will focus on our recent efforts in understanding and mitigating residual stresses in welding and additive manufacturing. The discussion will begin with dissimilar gas tungsten arc (GTA) welds, where the effect of mechanical tensioning loads was investigated and shown to significantly reduce tensile stresses. The next part will cover ferritic–austenitic welds studied using neutron diffraction and finite element modeling, which revealed a complex residual stress distribution characterized by high tensile stresses near the fusion line and significant variations across the ferritic and austenitic regions due to differences in thermal expansion and mechanical properties. Further results on dissimilar metal welds will then be presented, showing how thermal management, Ultrasonic Impact Treatment (UIT), and carefully designed welding procedures alleviate distortion and improve residual stress balance.

The talk will then transition to additive manufacturing, where residual stress mitigation has been examined through process optimization. In Wire and Arc Additive Manufacturing (WAAM), the effects of heat input, interlayer dwell time, and deposition path on stress reduction will be highlighted.

Overall, the presentation will provide a cohesive overview of residual stress mitigation strategies, illustrating how mechanical, thermal, and process-based methods can effectively reduce residual stress in welded and additively manufactured materials.