Corrosion fatigue is fatigue in a corrosive environment. It is a combined effect of a corrosive environment and cyclic tensions can cause crack growth in a material. It is the mechanical degradation of a material under the joint action of corrosion and cyclic loading. In corrosion fatigue, there is initiation and extension of cracks by the combined action of an alternating stress and a corrosive environment. In fact, the fatigue process causes rupture of the protective passive film, upon which corrosion is accelerated.