Numerical study of microstructural evolution in low alloy Cr-Mo steels during hydrogen attack

Hydrogen attack is a material degradation process which involves partial dissolution of the microstructure in favor of the growth of methane filled cavities. Two numerical models are discussed to study this multi-physics process: a simple one-dimensional model and the start of a more sophisticated microstructural model solved by a finite element technique. The first model shows that hydrogen attack involves a strong coupling between dissolution and cavity growth. The more elaborate model will be used to assess the validity of the assumptions of the first model.