Hydrogen Measurement and Failure Prediction

Abstract Solving the problem of hydrogen embrittlement is a critical goal for the energy industries. Research has traditionally focused on mechanisms while overlooking the causative aspects. Real-time measurement of hydrogen concentration in metals provides a direct pathway to mapping hydrogen embrittlement parameters as a function of deformation and fugacity. This approach enables the prediction of hydrogen embrittlement behavior in materials that have been systematically characterized, offering a quantitative framework to reconcile the contributions of hydrogen-enhanced localized plasticity (HELP) and hydrogen-enhanced decohesion (HED) mechanisms. The study also posits a newly recognized form of hydrogen embrittlement, where crack growth rate varies with stress intensity below the plateau region typically associated with constant velocity crack propagation. Practical implications emerge for cathodic protection design: by controlling applied potential, the degree of hydrogen trapping can be modified, revealing safe protection levels that mitigate failure within the design strain envelope. Specifically, it is shown that maintaining potentials around −900 mV provides effective mitigation against hydrogen embrittlement risks. This work highlights a transformative method for predicting and controlling hydrogen embrittlement in structural alloys.