Effect of corrosion medium composition on rate of crack growth in X70 pipeline steel

Abstract

The growth rates of corrosion cracks in X70 pipeline steel are determined in weakly acidic (pH 5.5) buffer solution with additives of a number of compounds that are a part of the soil electrolyte or are steel corrosion inhibitors. It is shown that the effect of components of electrolyte on the rate of crack growth agrees fairly well with their stimulating or inhibiting effect on the anodic dissolution of iron. The rates of hydrogen permeation into steel are measured and the effect of hydrogen absorbed by the metal on the anodic process in the studied corrosion media is considered.