Intergranular stress corrosion cracking an overview. This is, of course, a very complex question for a forum like this. Commercial titanium can suffer intergranular stresscorrosion cracking see stress corrosion cracking in methanolic environments and red fuming nitric acid but otherwise it is immune to failure. Characterization of the fracture surface was made using sem and seme. The required tensile stresses may be in the form of directly applied stresses or in the form of residual. Abstract although intergranular stress corrosion cracking igscc of highpressure gas pipelines has been known for more than 20 years, a transgranular.
Chloride is the leading cause of transgranular cracking. Transgranular stress corrosion cracking occurs mainly in chloride cracking of austenitic steels. 1 scope statement compile a report summarizing the history of s cc on pipelines, explaining the causes and factors. Recent research on custom 465, a precipitationhardened martensitic stainlesssteel based on the fecrni system, quantified and analyzed the corrosion and huptake behavior, the pittofatigue crack transition, the shortcrack growth and longcrack growth behavior, and the stresscorrosion cracking behavior. Transgranular stress corrosion cracking of highpressure. Although intergranular stress corrosion cracking igscc of highpressure gas pipelines has been known for more than 20 years, a transgranular form tgscc was detected more recently. Stress corrosion cracking of carbon steel in ethanol.
The impact of scc on a material usually falls between dry cracking and the fatigue threshold of that material. It is argued that the importance of many of the phenomenological factors that have been used to explain stress corrosion cracking lies in the influence that these factors exert on the. Transgranular attack has a very characteristic branching habit which is easily recognizable in scanning electron microscopy sem fractographic and metallographic section examination. Transgranular stress corrosion cracking is discussed and explained by a mechanism the essence of which is the inadequate repassivation of emergent slip steps. All observed cracks were transgranular in appearance and were associated with pits on the vessels inside surfaces. A study of the stress corrosion crack initiation stage in.