Residual stress study of welded high strength steel thin-walled plate-to-plate joints, Part 1: Experimental study

In this study, an investigation on the residual stress distributions near the weld toe of high strength steel thin-walled plate-to-plate T and Y-joints is carried out. Two groups of specimens, corresponding to welding preformed at ambient temperature and at a preheating temperature of 100 °C, are fabricated. The effects of preheating and joint geometry on the residual stress distribution near the weld toe are investigated by using the ASTM hole-drilling method. Furthermore, a study is also performed to evaluate the influence of brace plate cutting on the residual stress distribution near the weld toe of the joints. Experimental results obtained shown that tensile residual stress up to one third of the yield strength could appear near the weld toe and its value increases as the plate thickness and intersection angle increase. Furthermore, preheating was found to be an effective way to reduce the magnitude of residual stress while brace plate cutting could release the residual stress along the weld toes significantly.