Residual stress evaluation in multi-beads steel weldments using neutron difraction

Residual stress remains the single largest unknown in industrial damage situations. In this research the neutron diffraction technique was used to investigate and compare the residual stress characteristics in a several weld arrangements. Single and multi bead weld on a plate of low-carbon steel using the flux-cored arc welding (FCAW) process are presented. This research has focused on: 1) restraint during welding, 2) the effects at the start and end of the weld for a single bead, and 3) the effect of increasing the number of passes on the residual stress behaviour. The number and resolution of the measurements carried out in this work achieve a new level of detail and reveal significant features of the residual stress pattern in multi-bead welding. The intention is to provide key data for the validation of design, fitness-for-purpose methodologies and finite-element tools.