Comparison of Measured Residual Stress Distributions in Extra-Thick Butt Welds Joined by One-Pass EGW and Multipass FCAW

Abstract

This study is to measure the welding residual stress distributions in a 70 mm-thick butt weld by one-pass electron gas welding using both the inherent strain method and neutron diffraction method, respectively. Based on the measurement results, the characteristics of residual stress distribution through thickness were compared between one-pass electron gas welding and multipass flux-cored arc welding. Residual stresses in the specimens of electron gas welding measured by the inherent strain method and neutron diffraction method were well matched. The longitudinal residual stress in the multi-pass flux-cored arc welding is tensile through all thicknesses in the welding fusion zone. Meanwhile, longitudinal residual stress in electron gas welding is tensile on both surfaces and compressive at the inside of the plate. The magnitude of residual stresses due to electron gas welding is lower than that due to flux-cored arc welding.