促進腐食試験におけるアルミニウム合金/炭素鋼のガルバニック腐食挙動

Abstract

We investigated the galvanic corrosion behavior of aluminum alloy in contact with carbon steel during accelerated corrosion testing by evaluating the galvanic current and corrosion morphology of the coupled specimen. Electrochemical polarization curve was acquired before and after accelerated corrosion testing, with galvanic current only detected for aluminum dissolution. Aluminum next to the carbon steel was more severely corroded than remote aluminum. Corrosion was also observed in the carbon steel, although its dissolution current was not detected. Galvanic corrosion behavior was found to be dependent on the duration of exposure to water and the chemical composition of the aluminum alloy. The galvanic corrosion of aluminum was not only affected by the connected metal and the environment to which it was exposed, but also by the distance from the connected metal, and was dependent on the ion concentration of the connected metal.