Effect of cold metal transfer on corrosion properties of Duplex Stainless-Steel welds

Abstract: Duplex stainless steel (DSS), which consists of austenite and ferrite phases are widely use in chemical, petrochemical, offshore, railway and power generation sectors due to its excellent corrosion resistance, high strength, and easy formability. The Cold metal transfer (CMT) is an advanced method of droplet detachment for a dip transfer arc welding process. CMT mode of metal transfer in Gas Metal Arc Welding (GMAW) process used to develop butt welding in 8 mm plates of EN 1.4462 (2205) grade. General corrosion behaviour was determined by potentiodynamic in 0.1%N H2SO4 solution, while pitting corrosion susceptibility was studied by cyclic polarization test in 3.5 %NaCl solution. Pitting and crevice corrosion test performed as per ASTM G48 method A and B respectively. The findings demonstrate good general and pitting corrosion resistance with lower weight loss. Cyclic polarization results show greater value of Erp which indicates that after the damage of passive film in DSS once again passivated and if pitting initiates, it will not propagate because of passive film formation.

Keywords: Duplex Stainless steel, Cold metal transfer, Pitting corrosion, Crevice corrosion, Potentiodynamic test, Cyclic polarization test.