Failure assessment of SS304L-GI-EN24T dissimilar welded joints for application in milk transported tanker structure

This study investigated the strengthening mechanisms and failure analysis of dissimilar welded joints between SS304L stainless steel and EN24T mild steel. The mechanical characteristics and tensile failure performance of the joints were evaluated. The microstructures of different joint configurations (MS-MS, MS-SS, SS-GI, and MSGI) were first examined using SEM and EBSD analysis. Subsequently, tensile tests were conducted on four samples of these joints, which were prepared according to the ASME E8 standard. The MS-SS dissimilar welded joint exhibited the maximum load capacity of 35.71 KN, while the SS-GI joint showed the minimum capacity of 27.49 KN. The effects of weld thickness and specimen length on the strength of the joint structure were also studied. A Finite Element Method (FEM) model was developed for all cases and validated against the experimental results. The proposed FEM model shows very good agreement with the experimental data. The yield strengths of the dissimilar metal joints, as obtained from the UTM, were 320 MPa for MS-MS, 384 MPa for MS-SS, 343 MPa for MS-GI, and 325 MPa for SS-GI. This research demonstrates that the dissimilar metal weld joint, particularly the MS-SS configuration, is an effective and suitable choice for application in milk tanker structures.