Effect of mode of metal transfer on corrosion properties of duplex stainless steel welding

Abstract

Gas metal arc welding process used to develop butt welding on 8-mm plates of EN 1.4462 (2205) grade to meet higher productivity and excellent corrosion properties by using the dip or short circuit, globular, and spray modes of metal transfer. General corrosion behavior was determined by potentiodynamic in 0.1%N H₂SO₄ solution, while pitting corrosion susceptibility was studied by cyclic polarization test in 6% FeCl₃ solution. Pitting and crevice corrosion tests were performed as per ASTM G48 method A and B, respectively. The findings demonstrate that the specimen welded with spray transfer mode was found without any pitting on the surface with the lowest weight loss of 0.000005 g/cm² and 0.000109 g/cm² in the pitting and crevice test, respectively. No intermetallic phase was observed in optical microscopy up to 500 × for all modes of metal transfer specimens. The dip transfer mode sample shows the lowest corrosion rate at 2.310 mpy and 37.91 in potentiodynamic and cyclic polarization studies demonstrating very good general corrosion and pitting potential. The highest volume ferrite % was observed in the heat-affected zone than weld and base metal for all samples. However, the dip transfer mode specimen shows the highest % ferrite of 68.21%, 59.37%, and 51.02% in the heat-affected zone and weld and base metal. Spray transfer mode is recommended to weld 8-mm plates for welding joints for welding similar types of applications and testing media.