Investigation of Microstructural and Mechanical Properties of Dissimilar Metal Weld Between AISI 420 and AISI 1018 STEELS

The present study revealed that the martensitic stainless steel AISI 420 and mild/low carbon steel AISI 1018 could be successfully joined by using friction welding technique at different parameters such as friction time and friction pressure. Macro and microstructural characterizations of welded materials were performed by optical microscope (OM), X-ray diffractometer (XRD) and scanning electron microscope with energy-dispersive X-ray spectroscop. Also, tensile and microhardness tests were performed to determine the mechanical properties. The most interesting aspect of this study is the determination of ferrite, retained austenite and chromium phases in the weld zone by XRD analysis, and in tensile tests, the fracture occurred outside the weld zone at a maximum tensile strength of 527 MPa. Moreover, the diffusions of phases such as chromium and carbon were observed in the weld zone, and the microhardness measured in the weld zone was found to be higher with 591 HV than the one measured in the base materials.