A Statistical Review of Hydrogen Effects on the Fatigue and Fracture Behavior of Steel

This study conducts a statistical re-analysis of experimental data from the literature to assess the influence of hydrogen on key mechanical properties, including the medium-/high-cycle fatigue strength and the threshold value of the stress intensity factor range. The analysis employs linear regression, S-N curve plotting, and Paris' law regression. The results indicate that hydrogen has a minimal effect on the endurance limit of steel (estimated at (Formula presented.) cycles to failure), in contrast to the reductions in lifespan observed in the medium-cycle fatigue regime. Regarding crack propagation, the threshold value of the stress intensity factor range is reduced in the presence of hydrogen, particularly in conventional steel, which is more susceptible to hydrogen embrittlement than stainless steel. Conversely, systematic evaluation of constants linked to Paris' equation across various material types revealed considerable variability, suggesting a non-discernible trend in the response to hydrogen.