Analysis of microstructural, corrosion, and wear properties of austenite SS304 joints welded by underwater wet automated metal arc welding

This study explores the feasibility of using underwater wet automated metal arc welding. A specially designed welding setup was used, providing precise control over the x, y, and z axes to weld the high strength Austenite AISI304 stainless steel in present study. The welding process operated at 145 Amps of current, a voltage of 23 V, a feed rate of 2.5 mm/sec, and utilized a 3.15 mm × 350 mm flux-coated SS304 electrode, ensuring sufficient arc generation for effective welding. Microstructural analysis was conducted using optical microscopy and FESEM, while corrosion performance was evaluated through potentiodynamic tests, and wear characterization was performed using an engine tribometer. The weld zone exhibited a refined, columnar grain structure, which improved corrosion resistance, with a corrosion rate (CR) of 0.01052 mmpy, as determined by Tafel testing. Additionally, wear resistance tests revealed that the weld specimen outperformed the base metal, with a wear rate of 2.352 g/Nm × 10 −10 compared to the base metal's 3.201 g/Nm × 10 −10 . The results emphasize the potential of underwater wet automated metal arc welding in enhancing the structural integrity of marine constructions through improved corrosion and wear performance.