Non-destructive measurement of residual stresses in carbon steel weld joints

Residual stress measurements have been carried out on 8 and 12 mm thickness carbon steel single V weld joints by X-ray diffraction and ultrasonic tech niques. The maximum tensile and maximum compressive stresses on the surface of the 12 mm carbon steel weld joint are higher than those on the surface of the 8 mm carbon steel weld joint. The results also indicate that the var iation in the surface residual sti ess across the weld is different from th at for the through thickness residual stresses. The effect of constraint, w hich depends on the thickness of the weld joint, is found to influence the surface and through thickness residual stresses. The effect of stress relie f annealing heat treatment art residual stresses was also studied.