EFFECT OF 2ND-PHASE PARTICLES ON HYDROGEN EMBRITTLEMENT OF IRON-ALLOYS

The effect of hydrogen on the plasticity and fracture mode of pure iro n and iron containing iron oxides, aluminum oxide and cementite partic les has been studied. Cathodic hydrogen charging causes the embrittlem ent of Fe, Fe-Al2O3 and Fe-C alloys and little or no degradation effec t on Fe-FeO and Fe-FeO-Al2O3 materials, despite the high strength of t hose alloys and high amount of absorbed hydrogen. High hydrogen resist ivity of alloys containing iron oxides accounts for the weak iron oxid e/iron matrix cohesion established by the internal friction measuremen ts. The effect of hydrogen softening and hydrogen enhanced local plast icity in the resistance of studied alloys to the hydrogen action has b een discussed. Copyright (C) 1997 International Association for Hydrog en Energy.