ABSTRACT
This chapter shows that the theory of corrosion fatigue and related environmentally affected phenomena enter the framework of the theory of fatigue crack propagation. In corrosion fatigue, when a crack is “breathing” under cyclic loading, the pulsating fluid or gas flow is to be taken into account along with the diffusion process. In corrosion fatigue and related phenomena, the current material state depends on two and more damage measures. Along with the pure mechanical damage, damage as a result of environmental agents must be introduced. From the methodological point of view, there is no significant difference in modeling of crack growth under sustained or cyclic loading. Some complications are involved because the corrosion fatigue is frequency dependent. Hydrogen effect is an important component of the fatigue phenomena accompanied by electrolysis, say, in the presence of water or hydrogen sulfide. Even the biological environment generates hydrogen and produces effects which are often referred to as hydrogen embrittlement.
