A high-resolution characterization approach was employed to understand the effect of hydrogen on stress corrosion cracking (SCC) in austenitic alloys. Micro-mechanical testing, in the form of nano-indentation, on near (001) grains on alloys ranging from 12-70% Ni were performed with and without electro-chemical hydrogen-charging. The deformed region was further examined by TEM and the role of hydrogen on the dislocation mobility analyzed and compared between the different alloys. Furthermore, a coupled elastoplastic-transient hydrogen diffusion model was implemented using the UMAT-HT user sub-routine, to model the effect of hydrogen on materials under deformation. To validate this approach, simulated load- displacement curves are compared to those produced during this study and in the wider literature. Based on the results obtained during this study, the effect of hydrogen as a mechanism on SCC is discussed.
Materials by design for sustainable solutions in the energy, medical, transport, and engineering sectors
