Electrodeposition of Magnetite on Carbon Steel in Fe(III)-Triethanolamine Solution and Its Corrosion Behavior

Abstract

A dense and adhesive magnetite layer was successfully electrodeposited on a carbon steel in the Fe(III)-TEA solution. Electrochemical tests for the carbon steel and magnetite were conducted in an alkaline solution. These tests using the adherent magnetite specimens produced by electrodeposition is a new method to investigate the corrosion behavior of magnetite. The corrosion resistance of magnetite is superior to that of the carbon steel. When the magnetite and carbon steel are electrically contacted, the magnetite and carbon steel play the role of cathode and anode because the corrosion potential of the magnetite was higher than that of the carbon steel. If the magnetite and carbon steel are galvanically contacted to the equivalent area ratio (1 : 1), the corrosion rate of galvanic coupled carbon steel will increase by about 3.5 times than that of noncoupled carbon steel.

Micro-Galvanic Corrosion of Steam Generator Materials within Pores of Magnetite Flakes in Alkaline Solutions

“…Therefore, even if trace amount of Cu particles are present in the SG tube deposits, the Cu removal process should be included in the chemical cleaning process. As reported in many previous studies [4][5][6][7][8][9], this work again confirmed that magnetite accelerates the corrosion rate of SG materials by galvanic coupling. In addition, the results in this work had shown that metallic Cu and Pb as well as magnetite increased the corrosion rate of SG materials.…”

“…Recently, many investigations on the galvanic effect by magnetite on the corrosion behavior of secondary coolant system materials such as nickel-based alloys [4][5][6] and carbon steel [7][8][9] have been reported. It is well known that the SG deposits mainly consist of magnetite and are porous in nature [10,11].…”

“…Hence, an electric contact between SG structural materials and magnetite deposits could be occurred. In various secondary environments, it was reported that the corrosion potential of magnetite was higher than those of secondary system materials and the corrosion rate of the SG materials was greatly increased due to the shift in their potentials to the anodic direction [4][5][6][7][8][9]. Through the galvanic effect of magnetite on the SG materials, the mechanism on the galvanic corrosion of the secondary system materials coupled to magnetite is well established.…”

Corrosion Behavior of Alloy 600 Coupled with Electrodeposited Magnetite in Simulated Secondary Water of PWRs

“…The acceleration was due to the generation of hydrogen on the magnetite as well as the reduction of the magnetite itself in sulfate solution. 7) Jeon et al 8) reported that the corrosion rate of carbon steel coupled to magnetite increased by about 3.5 times than that of noncoupled carbon steel when they are contacted to the equivalent area ratio under alkalized reducing conditions of pH 9.5 which is a typical secondary water chemistry of PWRs.…”

Influence of Surface Roughness and Agitation on the Morphology of Magnetite Films Electrodeposited on Carbon Steel Substrates

“…More recently, in 2004, a pipe rupture accident occurred in the proximity of a flow-meter [7]. Aside from the wall thinning problem due to FAC, the corrosion rate of carbon steel piping with magnetite formation increases because magnetite is electrically contacted with carbon steel, resulting in a galvanic effect between the two materials [8,9].…”