TRISO (Tri-Structural Isotropic) Fuel

TRISO (Tri-Structural Isotropic) Fuel is an advanced nuclear fuel designed to retain radioactive fission products under very high temperatures and extreme reactor conditions. Each TRISO particle contains a small uranium fuel kernel, typically uranium oxycarbide or uranium dioxide, surrounded by multiple protective layers of porous carbon, dense pyrolytic carbon and silicon carbide. These coatings act as miniature containment systems, helping prevent radioactive material from escaping if the fuel is heated or damaged. TRISO particles can be formed into cylindrical fuel compacts or spherical pebbles for use in advanced reactors, including high-temperature gas-cooled reactors and some microreactors. The fuel is valued for its resistance to corrosion, irradiation and temperatures well above those tolerated by conventional nuclear fuel, supporting passive safety approaches in next-generation nuclear systems.