Helium is generally viewed as a benign element, as it is an odorless, tasteless and non-toxic gas. However, its formation during nuclear fusion has posed a materials challenge for this energy technology. The helium that evolves during hydrogen fusion infiltrates a fusion reactor’s structure as a series of bubbles that will eventually destroy metal.
The ability of nanocomposite solids to survive the impacts of helium in the core of a fusion reactor was evaluated by researchers from U.S. Los Alamos National Laboratory and Texas A&M University. The helium in these stacked metal layers of vanadium-copper-vanadium formed long channels, reminiscent of veins in living tissues, instead of bubbles. These channels ultimately interconnect into percolating “vascular” networks. This phenomenon could offer a solution to helium-induced damage by enabling outgassing of helium and other impurities while maintaining material integrity.
“Applications to fusion reactors are just the tip of the iceberg,” Dr. Michael Demkowicz, associate professor in the Department of Materials Science and Engineering at Texas A&M. “I think the bigger picture here is in vascularized solids, ones that are kind of like tissues with vascular networks. What else could be transported through such networks? Perhaps heat or electricity or even chemicals that could help the material self-heal.”