IDENTIFICATION OF THE DAMAGE IN HIGH STRENGTH STEELS AFTER ELECTROCHEMICAL HYDROGEN CHARGING *D. Pérez Escobar 1 , L. Duprez 2 , K. Verbeken 1,3, *, C. Miñambres 1 , M. Verhaege 1 1 Department of Materials Science and Engineering, Ghent University (UGent), Technologiepark 903, B- 9052 Ghent, Belgium (*Corresponding author: diana.perezescobar@ugent.be) 2 ArcelorMittal R&D Gent, J.F.Kennedylaan 3, B-9060 Zelzate, Belgium 3 Max-Planck-Institut für Eisenforschung, Max-Planck-Strasse 1, 40237 Düsseldorf, Germany * Postdoctoral fellow with the Fund for Scientific Research-Flanders (Belgium) (F.W.O. Vlaanderen) ABSTRACT Multiphase steels are quite sensitive to hydrogen embrittlement. Laboratory tests to evaluate this often use electrochemical charging to introduce hydrogen into the sample, but damage purely caused by hydrogen charging has to be avoided. A ferrite-bainite steel was charged using various conditions to identify when surface blisters occurred. Samples were also checked for internal damage by electron microscopy. This study was repeated for three other multiphase steels and pure iron. An HSLA steel was found to be more resistant whereas pure iron was quite susceptible to internal hydrogen damage. For all industrial steels, cracks concentrated in the middle of the sample were attributed to inclusions and segregations, inherent to production.