Effect of dissolved oxygen and coupled resistance on the galvanic corrosion of Cr-Ni low-alloy steel/90-10 cupronickel under simulated deep sea condition.

The influence of dissolved oxygen content (DOC) and coupled resistance on the galvanic corrosion rate of Cr-Ni low-alloy steel (FeCrNi) coupled with 90Cu-10Ni cupronickel alloy in simulated 500 m deep sea environment was investigated by means of weight loss measurements and scanning electron microscopy. The results indicated that the galvanic corrosion rate increased with the increase of DOC and decreased with the resistance increased. FeCrNi showed pitting corrosion in low DOC condition and uniform corrosion in high DOC sea water. Moreover, the galvanic corrosion rate at 50 at was bigger than that of 1 at. Galvanic corrosion rate was reduced 99% by increasing the resistance from 0 to 2000 Ω between FeCrNi and CuNi. The results of this research can be used to guide ocean engineering facilities design and galvanic corrosion control. [ABSTRACT FROM AUTHOR]