A fatigue failure mode its produced according to three specifyc steps:
The beginning of the microcracks in some especyfic point of the element
The microcracks evolve into macrocracks and develop parelels surfaces separted by longitudinal ridges. This surfaces could have dark an light marks known as beach marks. This beach marks depend of the fluctuation of the loads and the corrsive nature of the environment.
The element cant bear the loads anymore and the fracture occurs suddenly.
