Irradiation-tolerant nanostructured ferritic alloys: Transforming helium from a liability to an asset

Nanostructuredferritic alloys (NFAs) have the potential to make transformational contributions to developing advanced sources of fission and fusion energy. NFAs are Fe-Cr based ferritic stainless steels that contain an ultrahigh density of Y-Ti-O nanofeatures (NFs). The NFs provide both outstanding high temperature properties and remarkable tolerance to irradiation induced displacement damage as well as the degrading effects of transmutation product helium. Indeed, NFs can transform helium from a liability to an asset by forming a high density of nm-scale bubbles that act as sinks for point defects and helium may provide near immunity to radiation damage. This article outlines recent progress on engaging the challenges facing NFA development.