| Abstract Scope |
The susceptibility of high-strength carbon steels to hydrogen embrittlement (HE) depends on several parameters relating to metallurgical state and mechanical loading conditions. This dependence is associated with the interactions of hydrogen with various metallurgical heterogeneities (precipitates, carbides, dislocations, vacancies), which can influence both hydrogen diffusion and trapping processes, as well as hydrogen-assisted plasticity and damage mechanisms. In order to understand the nature of these interactions, and better identify their implications in the HE mechanisms of high-strength steels, we carried out several studies on large number of steels with different microstructures (martensitic and baintic), and chemical compositions in order to vary the nature of carbides and precipitates. We questioned the influence of this microstructural variability on hydrogen diffusion and trapping, and investigated the impact of hydrogen on mechanical behavior under different loading conditions. The results obtained enabled us to establish a link between hydrogen diffusivity and hydrogen-assisted damage mechanisms. |