Collaborative Research: DMREF: Developing Damage Resistant Materials for Hydrogen Storage and Large-scale Transport

With the promise of a hydrogen economy being closer to reality than it has even been, there is an important need for the design, development, and deployment of appropriate materials that can support and sustain the promise of a hydrogen-based infrastructure. One of the important scientific challenges associated with developing a hydrogen-compatible infrastructure is an understanding of the fundamentals of hydrogen-induced degradation in materials and developing appropriate hydrogen-resistant materials for storage and transport applications. By developing a computationally driven multi-scale modeling platform that will be informed by, and integrated with, experiments, this Designing Materials to Revolutionize and Engineer our Future (DMREF) project aims to accelerate the pace at which the controlling mechanisms of hydrogen embrittlement are discovered. As envisioned by the Materials Genome Initiative (MGI), this project will aim to enable the faster development of hydrogen-resistant materials for the energy transportation sector as it transitions from the transport of fossil fuels to hydrogen-based sources. Beyond the field of hydrogen storage and transport, the fundamental insights obtained from this project could also be helpful in designing fatigue- and corrosion-resistant sub-surface steel structures with longer lifetimes, which could enable materials designs for many other industries as well. This project aims to advance fundamental knowledge of crack tip processes that control damage accumulation and propagation under fatigue loading and the role of hydrogen in making the material more susceptible to fracture. It is hypothesized that the controlling mechanisms occur in the plastic zone around the crack tip, over a length scale of about 1 to 10 microns, which is too small for continuum theory to be predictive and too large for atomistic simulations to handle by brute force. Such a knowledge gap at the mesoscale will be closed through a tightly coupled experimental-computational program. Computational efforts will build upon the recent advances made in atomistic simulations, dislocation dynamics simulations, with insights on crystal plasticity and continuum-level modeling. The experimental efforts will leverage improved and unique capabilities that include nanoindentation, x-ray tomography (in conjunction with Brookhaven National Laboratory), and in situ testing in hydrogen environments (to be conducted at Sandia National Laboratory). By combining modeling and experiments over multiple length-scales, an experimentally validated multi-scale model for hydrogen effects on fatigue evolution in ferritic steels could be established. Insights obtained from this project have the potential to lead to the development of reliable engineering roadmaps for life prediction and risk assessment for hydrogen storage and transport structures. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.