Corrosion Cracking of Kh70 Pipe Steel under the Conditions of Cathodic Protection

Abstract

We study the mechanism of corrosion cracking of Kh70 steel in a neutral soil electrolyte under the conditions of cathodic protection. We distinguished three areas of potentials in which the processes of corrosion cracking of steel are governed by different mechanisms. Thus, the process of local anodic dissolution proves to be predominant under potentials more positive than – 0.75 V, the mechanism of hydrogen embrittlement is predominant under potentials more negative than – 1.05 V; at the same time, both these mechanisms act within the range of potentials from – 0.75 to – 1.05 V.