Investigation on effect of pulse correction on structure property in dissimilar welds of galvanized steel and aluminum alloy obtained by gas metal arc welding cold metal transfer

Abstract

Gas metal arc welding cold metal transfer (GMAW-CMT) method with AlSi₃Mn filler wire was performed on welding of the 5754 aluminum alloy with thickness of 3 mm to the galvanized steel with thickness of 2 mm aluminum alloy to investigate the effect of pulse correction on structure and mechanical properties of welded samples. In accordance with results, GMAW-CMT provides good tensile performance. It was attributed to the various throat weld size and wetting actions because of the influence of pulse correction on structure of welded joints. It was inferred that on employing +5 pulse correction resulted in better and consistent tensile strength of 209 MPa. Furthermore, the results showed that increasing the pulse correction led to increasing of flow in the filler wire and in fact raising of brazed seam width and throat weld size. In addition, the thickness of intermetallic compound layer which was formed along the interface during the GMAW-CMT was varied by changing of pulse correction. It has been found that by increasing the pulse correction from–5 to +5, the throat weld size increased and consequently led to a change in the tensile strength of the welded joints.