Modeling the influence of hydrogen on the short fatigue crack growth in a metastable austenitic stainless steelThursday (29.09.2016) 10:00 - 10:15 Part of:
A microstructurally-based model is implemented including different crack propagation mechanisms to understand the influence of hydrogen on the short fatigue crack growth in the metastable austenitic steel AISI304L. Stresses and displacements will be calculated based on a two-dimensional dual boundary element method.
The polycrystalline microstructure and the elastic anisotropic properties of each grain as well as the crack growth along slip bands are considered. Furthermore, the deformation-induced phase transformation from γ-austenite to α’-martensite is considered in the crack tip region.
The local hydrogen distribution is calculated by taking into account local hydrostatic stresses and will be updated according to transient diffusion processes. It also influences the activation of slip bands and the corresponding microstructural flow stress.
Due to these effects the fatigue crack growth mechanisms will change compared to simulations of short fatigue crack growth in air. The results obtained in the model will be discussed and compared with short fatigue cracks observed in AISI304L.