Analysis metallography and corrosion rate prediction on ASTM A36 steel from SMAW underwater welding

Underwater welding is a commonly used welding method for dealing with damages to marine building infrastructure such as ships, offshore platforms, or pipelines. These damages occur due to environmental cyclical loads, accident loads, and corrosion effects. Slow reparation handling will result in enlargement of crack propagation that occurs, this can lead to leakage or failure. This research focuses on underwater SMAW wet welding ASTM A36 steel with variation of electrode and heat input to mechanical properties, metallography, and corrosion rate prediction. The electrode used is AWS E6013 and AWS E6019 with variation of heat input 0.65 kJ / mm and 1 kJ / mm. Based on the result of research, it is concluded that welding using AWS E6019 electrode with heat input 1 kJ / mm get best result with 338 MPa (yield strength) and 448 MPa (ultimate strength) tensile strength, HAZ macro structure width 3.2 mm, ferrite percentage in weld metal structure of 51%, and the corrosion rate prediction of 0.491 mmpy.