recently, grave explosions in the oil and gas transport tubes, as well as, the rapid failure of the machine parts in service, were caused by hydrogen cracking. during solidification of metals, in casting ,welding, cathodic charging, etc., the hydrogen can enter in metals and cause premature cracking. the hydrogen embrittlement in metals is accompanied with a charge in the type of fracture surfa...

Abstract The present work investigates the resistance of a progressively cold-drawn carbon steel wire against hydrogen embrittlement. In this study, analytical and numerical methods are used to determine critical content, ratio embrittlement indices different material conditions. with highest degree cold deformation shows content improved At higher degrees deformation, stronger trapping, which ...

As part of a multi-scale approach for modeling hydrogen embrittlement in hardened steels we have investigated, employing density functional theory methods, the stability and concentrations of the point defect clusters present in metastable Fe-C-H alloys with vacancies. The defect spectrum is found to be strongly dependent on the local vacancy concentration, and for low hydrogen levels sharp hig...

The results of recent molecular dynamics simulations of displacement cascades in iron indicate that small interstitial clusters may have a very low activation energy for migration, and that their migration is 1 -dimensional, rather than 3-dimensional. The mobility of these clusters can have a significant impact on the predictions of radiation damage models, particularly at the relatively low te...

In this study, the hydrogen transport phenomenon was numerically evaluated by using hydrogen-enhanced localized plasticity (HELP) mechanisms. Two dominant governing equations, namely, the hydrogen transport model and the elasto-plastic model, were introduced. In addition, the implicitly formulated equations of the governing equations were implemented into ABAQUS UMAT user-defined subroutines. T...

Helium accumulation negatively impacts structural materials used in neutron-irradiated environments, such as fission and fusion reactors. Next-generation fission and fusion reactors will require structural materials, such as steels, that are resistant to large neutron doses yet see service temperatures in the range most affected by helium embrittlement. Previous work has indicated the difficult...