Effect of Welding Current on Tensile Properties of Low Carbon Steel Sheets in Resistance Spot Welding

Resistance spot welding that is one of the oldest electric welding processes in use by industry today is joining technique which is used for almost all known metals. Since, the low carbon steel sheets are widely used in bodies of SCANIA busses high strength and good quality for welded joints should be provided in assembling these steel sheets. Present research investigates the effect of welding current on tensile-shear and tensile-peel strengths of steel sheets having 1 mm thickness. An ELECTRO TECHNO TAK Model DR Series S 1002 welding machine having 130 kVA capacity and pneumatic application mechanism with a single lever was used in the experiments. The electrode pressure was fixed at 7 kN. Different samples obtained by employing welding periods of 6, 9 and 12 cycles were produced and the welding current was increased from 3 to 9 kA. Having finished the welding processes, the prepared welding specimens were exposed to tensile-shear and tensile-peel tests and the obtained results were presented in graphical forms, which help in selecting the optimum welding current to achieve the desired mechanical properties for weld quickly.