Residual Stresses and Near-surface Material Condition of Welded High Strength Steels after Different Mechanical Post-weld Treatments

摘要

Investigations on high strength steel S690QL butt welds with differentmechanical post weld surface treatments have been carried in order toshow how different treatment intensities are interacting with the nearsurface residual stress condition and at least with the resulting fatiguestrength. Experiments with high frequency hammer peening techniquesin comparison to shot peening processes reveal, that the penetrationdepth of the induced compressive residual stresses is higherafter the application of the hammer peening processes. However thisdoes not necessarily lead to the best residual stress distribution becausehigh intensities may also produce detrimental tensile residualstresses in deeper surface layers. Finally the results show, that thecombination of different measurement techniques enables a reliablecharacterization of such treatments.