Vol.23, No.3, 2023, pp. 307–317
UDC:

This work covers the review of previous studies on the corrosion of welded joints of duplex stainless steel (DSS) from 2015-2022. DSS alloys have been welded using a variety of processes including laser fibre, gas tungsten arc, shielded metal arc, and underwater flux-cored arc welding. The predominant corrosive media these welded joints were subjected to in corrosion studies were NaCl (1 M), ferric chloride (6 %), MgCl₂ (45 wt.%), HCl (1 M), and H₂SO₄ (2 M). The reported results revealed that the Mo concentration in hyper-duplex stainless steel was shown to not affect weldment corrosion; rather, low pitting resistance equivalent number (PREN) austenite regions and austenite-ferrite grain boundaries were prone to pitting and intergranular corrosion. The material's stir (friction) welded joint (S32750) was reported to have the best corrosion resistance in NaCl (1 M). The weldment of the DSS joint generated by gas tungsten arc welding was found to be more resistant to pitting than that produced by shielded metal arc welding.

Keywords: corrosion, duplex stainless steel, weldment, pitting, welding