Influence of Welding Residual Stress on the Mechanical Behavior of Externally Loaded Dissimilar SS400-STS304 Steel Weldment

Abstract Thermal and mechanical characteristics in dissimilar SS400-STS304 steel weldment have been investigated by 3D thermal elastic-plastic analysis. Moreover, the influence of welding residual stresses on the mechanical behaviour of this welded joint, by applying superimposed external load (tension load) was determined. The residual stresses obtained by numerical simulation were compared with the experimentally measured results. The FE results were in good agreement with the measured values. The mechanical test (hardness, tensile test) and metallurgical analysis was carried out to ensure the weld integrity. Hence, possibility of applying SS400-STS304 dissimilar steels in industries has been established.Key Words : Dissimilar SS400-STS304 steel weldment, 3D thermal elastic-plastic analysis, Welding residual stress, External load 1. INTRODUCTION Residual stresses and distortions are two of the major concerns in welded structures. Welding residual stresses not only cause distortion but also significantly affect the service characteristics of welded structures. The residual stresses in weld region are normally tensile and close to the material yield stress due to the shrinkage of the weld on cooling. The combination of high tensile residual stresses in weld region and tensile loads applied can promote brittle fracture that increases the susceptibility of weld to fatigue