Learning more about stress corrosion cracking.

When a part cracks, it is sometimes difficult to assess the cause, which can be multiple: actually, the combined action of stress and environments can lead to mechanical failure. Depending on the failure mechanism, we can then consider the cause of the stress corrosion cracking (SCC), the corrosion fatigue cracking (CFC), and the hydrogen-induced cracking (HIC).

Particularly, SCC can be responsible for the growth of cracks due to the simultaneous action of tensile stress and a corrosion environment on active metals or alloys such as chloride ions, water, oxygen, and pH.

The development of stress-corrosion cracks involves both crack initiation and crack propagation.

Many models to explain SCC mechanisms have been proposed in the literature but they are specific to certain alloys in specific environments; it is important to understand that there is no universal model that explains various mechanisms proposed for SCC because of the inconsistency in SCC.

Various models will be discussed such as film rupture-slip dissolution (FRSD), film-induced cleavage (FIC), localized surface plasticity (LSP), and atomic surface mobility (ASM). It will also present the metallurgical point of view of SCC. Some ways of prevention of SCC will be given.