10 – Assessing residual stresses in predicting the service life of welded structures

: The intention in this chapter is to demonstrate the potential of modern techniques based around sophisticated instruments and software, in assessing residual stress distributions experimentally in both thin and thick specimens, to support numerical modelling of residual stresses as a function of weld process and material parameters (calibrating these models against the experimental data), and to assist with predicting likely relaxation of stresses under cyclic loading. Analysis of this type of comprehensive data will lead to a much broader and more detailed understanding of the influences of various material, process and loading parameters on residual stress development and redistribution. It should then be possible to incorporate this understanding into refined versions of existing structural integrity codes and use modern alloys and welding processes more efficiently in terms of lean structural design.