Comparative evaluation of residual stresses in vacuum electron beam welded high strength steel S960QL and S960M butt joints

Abstract

In this letter, the residual stress (RS) induced by the high vacuum (2 x 10−4 mbar) electron beam welding (EBW) of two high strength steels (HSS) i.e. quenched and tempered (Q + T) steel and thermo mechanical controlled steel (TMCP) with plate thickness 15 mm for specific applications in construction engineering, vehicle industry (trucks, mobile cranes, railway vehicles) etc. was analysed. X-ray diffraction (XRD) method has been used for the comparative analysis through the surface RS distributions in EB welded HSS, S960QL and S960M butt joint. Combination of power beam process with cutting edge technology of residual measurement for HSS characterise the novelty of this study. The results showed that the maximum longitudinal tensile stress near the weld toe of the EB welded S960QL joint is higher than the S960M. The transverse residual stress in the S960QL and S960M welded samples shown the characteristic W-shape of residual stress distribution.