Measurements and predictions of diffusible hydrogen escape and absorption in catholically charged 316LN austenitic stainless steel.

Hydrogen can have an impact on the service life of safety critical components, such as coolant pipes in nuclear reactors, where it may interact with other factors including irradiation. Hence, it is important to characterise such behaviour which in turn requires the capability to charge representative material specimens with hydrogen and to quantity the levels of hydrogen present. Hydrogen concentrations resulting from cathodic charging of 316LN stainless steel over short time periods (< 2 h) were estimated from hydrogen release rates obtained from potentiostatic discharge measurements and used to calibrate simulations based on Fick's second law of diffusion in order to predict the hydrogen concentration after 24 h of charging.