The effect of heat input on tensile strength, Vickers hardness, and microstructure on DMW of AISI 1015 and 304L SS through the GMAW process

Purpose: This experiment was to evaluate the effect of heat input on tensile strength, Vickers hardness, and microstructural observations. Design/methodology/approach: The materials welded are AISI 1015 and 304L SS, and the joining process is Gas Metal Arc Welding (GMAW). The filler electrode used is ER70S-6 with a diameter of 1.2 mm, and the workpiece size is 300 x 125 x 3 mm with a butt-joint connection. The variations in welding current applied are 120, 130, and 140 A. Meanwhile, the voltage and welding speed in the experiment were kept constant. Findings: The maximum tensile test index was 380.08 MPa, and the Vickers hardness index was 376.85 HV, with the maximum heat input being 0.5943 kJ/mm. The macro- and microstructure, as well as structural inspection of the welded joints, were observed in the experiment. The best heat input effect for the DMW technique between 304L SS and AISI 1015 is 0.5943 kJ/mm at a plate thickness of 3 mm. Research limitations/implications: Dissimilar Metal Welding (DMW) is widely applied in the power generation industry. Materials generally joined using the DMW technique are austenitic stainless steel (304L SS) and low carbon steel (AISI 1015). Practical implications: Using the proposed heat input approach is important for the dissimilar welding industry application to obtain the right product for its expected use. Originality/value: This paper presents the differences in heat input to reveal the weld properties by dissimilar welding processes, where the properties will be adapted for a particular use. Particularly in the application of dissimilar joints between 304L SS and AISI 1015 with a thickness of 3 mm, which requires an average tensile strength of around 380.08 MPa and an average yield strength of about 320.16 MPa, the heat input parameter can be recommended as 0.5943 kJ/mm.