Residual stress distribution in steel butt welds measured using neutron and synchrotron diffraction.

70 keV synchrotron radiation and thermal neutrons have been employed to investigate the residual stress characteristics in a fully restrained, steel, butt weld. The focus is on the values of the subsurface and through-thickness strain/stress variation in the middle of the weld. The advantages and limitations of the techniques have been addressed, in relation to the gauge volume, the stress-free reference sample and positioning. The measurement of residual stress around the weld achieved in this work significantly improves the resolution at which residual stress in welded components has been determined.