抄録
Corrosion of iron and steel in neutral solutions of potassium chloride has been studied with rotating ring specimens. Since the oxide film deposited on the metal surface is much affected by small change of conditions, the corrosion rate vary significantly. The ratio of the maximum corrosion rate to the minimum rate, or to the average rate, is considered to be the“Safety Factor” under general corrosion conditions. The ratio was once recorded to be 1.5-2.5 in aerated solutions of KCl at 50°C, and was almost independent of the carbon and copper contents, probably due to the short-range experiment for only 100 hours.
The physico-chemical properties of oxyhydroxide that precipitated in the solution containing ferrous and/or ferric chloride were studied, i.e., the pH titration was carried out with a great variety, and the precipitates were examined by X-ray diffraction. Oxidation of both ferrous ions and oxyhdroxide precipitate with oxygen dissolved seems to be a major factor for formation of oxide film on ferro-metals.
