Effect of CMT Technique on Properties of Duplex Stainless-Steel Welding

A significant innovation in the domain of arc welding is the cold metal transfer (CMT) technique, which operates under conditions of reduced thermal input, ensures superior stability in arc length, and facilitates nearly spatter-free welding outcomes. The CMT mode was employed to fabricate butt-welded junctions of 8 mm plates of EN 1.4462 (2205) grade. The integrity of the weld joint was scrutinized and validated through non-destructive testing methodologies, including visual testing (VT), liquid penetrant testing (LPT), and radiographic testing (RT). Additionally, a series of destructive assessments, encompassing tensile, bend, hardness, and impact tests, were conducted and found to be compliant with the pertinent standards. The findings of this investigation indicate that the CMT mode of arc welding yields weld joints with commendable properties, fulfilling the criteria established by both nondestructive and mechanical and corrosion testing protocols. Good general corrosion behaviors were detected by scanning potentiodynamics in 0.1% N H2SO4 solution, while excellent pitting corrosion susceptibility was observed by using the cyclic polarization test in 3.5% NaCl solution. The pitting and crevice corrosion tests performed as per ASTM G48 methods A and B were reported to show very low weight loss. Cyclic polarization results show a greater value of the potential Ere-pass, which indicates excellent re-passivity behavior—as a result of repair of a passivation-providing film—to avoid further propagation of corrosion.