Stress corrosion cracking at a screw - 1.4404
Stress corrosion cracking occurs when the component contains tensions (internal stresses or tensile stresses) and a corrosive medium has an effect. Specially chlorides and strong alkaline solutions are confessed as triggers of this kind of corrosion. After expiry of an incubation period microscopically fine incipient cracks develop first. Visible cracks arise from it later. The arising cracks spread vertically to the direction of the tensile stresses. In most cases they are running transcrystalline, seldom intercrystalline. Stress corrosion cracking can lead to the break of the component. In the following case a screw is affected by this defect type.
Screw M6 - solution annealed , cold formed