Study on hydrogen permeation and stress corrosion cracking behaviors of AISI 4135 high-strength steel with macrofouling adhesion in marine immersion zone

A field exposure test was set up to study the effect of macrofouling adhesion on hydrogen permeation and stress corrosion cracking (SCC) behaviors of a high-strength steel in marine immersion zone, and the results were further verified by laboratory electrochemical simulation tests. The results indicated that the crevices formed by macrofouling adhesion can promote localized corrosion pits and change the local chemical environment. More severe localized corrosion can increase the hydrogen permeation current density and promote the SCC of high-strength steel. As a comparison, the hydrogen permeation current density of steel under cathodic protection state was slightly decreased owing to the shielding effect of macrofouling.