Uranium zirconium hydride (UZrH,), a dispersion of metallic uranium in a matrix, is used as the fuel in TRIGA reactors.[1] UZrH fuel is used in most research reactors at universities and has a large, prompt negative fuel temperature coefficient of reactivity, meaning that as the temperature of the core increases, the reactivity rapidly decreases.[2]
Franco-Belge de Fabrication du Combustible, in Romans-sur-Isère, France, is the only manufacturer of this fuel.[3]