Corrosion of AF1410 steel electron beam welding joints in simulated marine environment

The corrosion electrochemical impedance spectroscopy characteristics of AF1410 steel electron beam welding joints at different positions and for different exposure time were investigated in a simulated marine environment by neutral salt spray testing.The corrosion resistance and the electrochemical behaviors of the weld fusion zone and the base metal were evaluated according to the microstructure analysis of the welded joints.The investigation of open circuit potential and impedance spectroscopy indicates that thick tempered martensite and carbide precipitates at the weld fusion zone are easy to form a corrosion cell,and the corrosion reaction resistance is less than that of the base metal,which easily leads to electrochemical corrosion.Equivalent circuits of impedance spectroscopy were established and fitted for the different corrosion stages.