35 Fatigue Crack Growth of Pipeline Steels in Gaseous Hydrogen- Predictive Model Calibrated to API-5L X52 Available to Purchase

A phenomenological fatigue crack growth (FCG) model was previously proposed to predict the FCG of API-5L X100 steel in high-pressure gaseous hydrogen [1]. The model presumes that total FCG is a summation of a “pure” fatigue component and a hydrogen-assisted (HA) component. The hydrogen-assisted fatigue component is further divided into two regimes. The first regime is dominated by the stress-assisted hydrogen concentration within the fatigue process zone, while the second regime is controlled by the far-field steady-state hydrogen concentration. This work outlines the process entailed in model calibration to X52 steel in gaseous hydrogen. Model applicability to multiple materials, having differing microstructure and characteristic length scales, will be discussed in light of the model parameters and potential FCG mechanisms.