Hydrogen Concentration Profile Prediction in Pipeline Steels: a Finite Element Modelling approach based on Experimental Diffusion Coefficients

The accurate determination of hydrogen diffusion coefficients in pipeline steels is essential for predicting hydrogen distribution and assessing material performance in hydrogen-rich environments. This study focuses on the measurement of hydrogen diffusion coefficients in commonly used pipeline steels, including API 5CT T95, P110, and API 5L X60, using electrochemical permeation tests performed according to the Devanathan–Stachurski technique. To extend the understanding of hydrogen diffusion beyond experimental measurements, Finite Element Modelling (FEM) was employed to investigate hydrogen concentration profiles within steel samples under various charging conditions. The FEM simulations incorporated the experimentally determined diffusion coefficients, enabling accurate prediction of hydrogen distribution as a function of time and environmental conditions. This approach helps optimize hydrogen charging conditions and assess hydrogen embrittlement risks in pipelines exposed to hydrogen.