| 摘要 |
874,964. Nuclear fuel materials. UNITED KINGDOM ATOMIC ENERGY AUTHORITY. May 19, 1959 [May 30, 1958], No. 17448/58. Class 39(4). A ceramic nuclear fuel material comprises particles of an oxide of a fissile or fertile metal and particles of a refractory oxide of an element of low neutron absorption crosssection, the particles being dispersed in a vitreous material of melting point above 1000‹C. The fissile oxide may be uranium dioxide and the refractory oxide alumina, magnesia, beryllia, or hafnium-free zirconia. A suitable vitreous material is a glass formed from alumina, silica, and a basic oxide such as lime or magnesia. The fuel material may be formed by mixing the constituent oxides with an organic binding agent (e.g. a mixture of polybutyl methacrylate, dibutyl phthalate, and acetone), cold pressing into pellets, and sintering at about 1500‹C. in an atmosphere of nitrogen, hydrogen, or cracked ammonia. In Example III a mixture of alumina, silica, magnesia, and lime is sintered first, ground to a fine powder, and then mixed with uranium dioxide and more alumina before pressing. The fuel material has a low permeability to fission product gases at high temperatures. |
