ABSTRACT
In this chapter, the damage mechanisms leading to the formation of various types of physical damages in metallic materials are discussed. Particularly, alternating slip is responsible for formation of persistent slip bands, which will eventually lead to transgranular fatigue crack nucleation and propagation. On the other hand, grain boundary cavitation can be caused by multiple mechanisms including vacancy condensation and grain boundary sliding, which will lead to intergranular fracture. In addition, environment has a strong influence on the surface damage of metallic materials via oxidation and corrosion. In complex engineering alloys and coatings, oxidation is related to multi-element diffusion, and the problem is solved in such a way with an example for MCrAlY coating. It is important to recognize the nature of such physical damages, as they play different roles in the holistic damage accumulation process under general loading conditions.
