Effect of Ni on Corrosion Resistance of Plate Corten Steel in Marine Atmospheric Environment

The addition of alloying element Ni in steel can positively shift its self-corrosion potential and thus increase its stability. The results of atmospheric exposure study show that plate corten steel with about 4% Ni can significantly improve its corrosion resistance in Coastal Atmospheric environment. Japanese scholars have studied the corrosion resistance of 3% Ni plate corten steel in seashore environment. The results show that the corrosion rate of plate corten steel is slow due to the enrichment of Ni element in the rust layer, which refines the grain size of the rust layer, increases its compactness and produces a protective rust layer. Therefore, it is difficult for chloride ion to contact the steel matrix through the rust layer. The rate has been reduced.

Diaz et al. used a traditional plate corten steel and three plate corten steels with 1%, 2% and 3% Ni respectively to expose to the ocean atmosphere eroded by chloride ion for one year. The results show that, due to the presence of Ni, the plate corten steel containing Ni exhibits better corrosion resistance after one year exposure in marine atmospheric environment, and the higher the content of Ni, the better the corrosion resistance. This is due to the presence of Ni in plate corten steel, which promotes the formation of nanophase and superparamagnetic alpha-FeOOH in the inner rust layer, and the particle size of the formed alpha-FeOOH is less than 15 nm, thus increasing the compactness of the inner rust layer, thus improving the ability to resist the ocean atmospheric erosion.