The effect of acidification on hydrogen uptake and corrosion resistance of advanced high-strength steels

High strength steels are susceptible to hydrogen embrittlement that may contribute to degradation of steel parts and structural failure. The correlation between corrosion-induced hydrogen entry and electrochemical behavior of galvanized advanced high-strength steel (Press Hardened Steel and Complex Phase Steel) was studied in neutral and acidified (pH 3) 0.05 M NaCl by combination of conventional and localized electrochemical techniques with zero resistance ammeter technique and thermal desorption analysis. Hydrogen entry increased in acidic environment due to lowered galvanic protection of both coatings. In Press Hardened Steel, it was additionally aggravated by pitting of insufficiently galvanically protected steel. • Galvanized Press Hardened Steel and Complex Phase Steel were studied and compared • The correlation between hydrogen entry and electrochemical behavior was revealed • Galvanic protection differed significantly in neutral and acidified electrolytes • Coating composition affected galvanic coupling and formed corrosion products • Hydrogen entry in Press Hardened Steel was aggravated by pitting in 0.05M NaCl (pH 3)