Corrosion fatigue mechanisms, metallic crack initiation

Duquette, D. J., Mechanisms of crack initiation and propagation in corrosion fatigue , Proc. Int. Conf. on Mechanisms of Environmental Cracking in Materials, University of Surrey, 4-7 April 1977, The Metals Society, pp. 305-21 (1977)... 

In the first group, emerging persistent slip bands (PSBs) are preferentially attacked by dissolution. This preferential attack leads to mechanical instability of the free surface and the generation of new and larger PSBs, followed by localized corrosion attack, resulting in crack initiation. Under passive conditions, the relative rates of periodic rupture and reformation of the passive film control the extent to which corrosion reduces fatigue resistance. When bulk oxide films are present on a surface, rupture of the films by PSBs leads to preferential dissolution of the fresh metal that is produced.102... 

Metal fatigue is the process of crack initiation and growth due to the action of a fluctuating mechanical stress. Corrosion fatigue is simply metal fatigue that... 

Depending on the corrosion and metal surface reactions, different types of corrosion can occur under different conditions (Fig. 1-1). The types of common electrochemical corrosion are usually subdivided into corrosion without mechanical stress and corrosion with mechanical stress. Pitting corrosion or selective corrosion can sometimes initiate other types of corrosion damages, e.g. stress-corrosion cracking or corrosion fatigue. The various types are discussed in the following section. 

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