what is Stress corrosion cracking ?

Stress Corrosion cracking (SCC) this phenomenon can be defined as material cracking due to the combined effect of static stress and corrosion. The stress involved can be residual stress and actual stress from an external load. The corrosion that occurs is generally very localized. Localized corrosion on the surface of the material usually acts as a stress raiser or stress concentrator. This corrosive cracking can be either transgranular or intergranular cracking depending on the type of alloy, metallurgical and environmental conditions. there are 3 main causes that determine the occurrence of Stress Corrosion Cracking are: Tensile stress. This tensile stress can be a residual stress that occurs due to welding or metal forming and can be a real stress due to the workload received by the material. For example, a pipeline or pressure vessel that is operated with internal pressure. Temperature. In general, cases of Stress Corrosion Cracking occur at temperatures > 60 C The availability of certain ions, such as Chloride (Cl) ions. Until recently, engineers still have difficulty determining definite limits on the minimum limits for Stress Corrosion Cracking  triggers In general, Stress corrosion cracking resistant materials are stainless steel duplex or super-ferritic type. avoiding residual stress to[…]

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