Nickel Alloys, stainless steel & Titanium Rods

Metal rods have the advantage of a much higher heat conductivity than oxide fuel rods but cannot survive equally high temperatures. Metal fuels have a long history of use, stretching from the Clementine reactor in 1946 to many test and research reactors. Metal fuels have the potential for the highest fissile atom density. Metal fuels are normally alloyed, but some metal fuels have been made with pure uranium metal. Uranium alloys that have been used include uranium aluminium, uranium zirconium, uranium silicon, uranium molybdenum, and uranium zirconium hydride (UZrH). Any of the aforementioned fuels can be made with plutonium and other actinides as part of a closed nuclear fuel cycle. Metal fuels have been used in water reactors and liquid metal fast breeder reactors, such as EBR-II.