2007 Volume 56 Issue 4 Pages 132-147
Characteristics of hydrogen-related failure are reviewed from mostly experimentally observed features. Comparison with the failure under normal atmospheres is made so as to extract the way by which hydrogen plays a role in the fracture process. Fractographic features associated with plasticity and the promotion of the crack initiation and growth analyzed by means of an R-curve method are presented. Enhanced plastic instability is noted as a precursor of the failure. Effects of hydrogen on stress relaxation and creep are presented as the dislocation dynamics that operate on delayed fracture. Effects of environmental variation of applied stress and external hydrogen potential are also presented.