Effect of Binary Oxide Flux on Weld Shape, Mechanical Properties and Corrosion Resistance of 2205 Duplex Stainless Steel Welds

Abstract

Duplex stainless steel (DSSs) is characterized by excellent corrosion resistance with high strength. Twelve single-component fluxes (TiO2, Fe2O3, Cr2O3, ZnO, ZrO2, CaO, Mn2O3, V2O5, MoO3, SrO, MgO, and LaO2) were tested in the initial experiment using activated Tungsten inert gas (ATIG) technic, and then three couples of oxides were selected as binary fluxes (Fe2O3-Cr2O3, ZnO-Mn2O3, and V2O5-Mn2O3) for the rest of the study. The results show that the depth weld of binary oxides (Fe2O3-Cr2O3, ZnO-Mn2O3) was increased by 3.7 times in comparison with tungsten inert gas (TIG) weld bead. The hardness and the tensile strength of welds carried out with Fe2O3-Cr2O3 and ZnO-Mn2O3 binary fluxes were close to those of the parent metal. Weld bead executed with ZnO-Mn2O3 oxides has more capability to withstand sudden loads. Potentiodynamic polarization tests were performed. The metal welded with flux composed of Fe2O3-Cr2O3 has been found the most resistant to corrosion.