A method for the preparation of compounds with parts of impregnated graphite, in particular a method for the production of core fuel elements with a huelle of graphite, the with molten metals or light metal alloys waterproof and the fuel element is thus produced

摘要

1,157,863. Brazing. EUROPEAN ATOMIC ENERGY COMMUNITY (EURATOM). 8 March, 1967 [9 March, 1966; 18 Jan., 1967], No. 10975/67. Heading B3R. [Also in Division G6] A process for producing a tight connection between two members, one of which is made of graphite, the other of which is made of graphite or metal, comprises screwing the members together and heating them in an autoclave under vacuum conditions, and impregnating the members with metal so as to render the graphite impervious, whilst simultaneously dip brazing the members by means of the molten impregnating material. The members may comprise a graphite fuel can 1, Fig. 1, containing uranium carbide pastilles 2, two hermetic graphite boxes 3, 4, two graphite closure plugs 5, and a ductile layer 6 of the impregnating material. In a modification the fuel element comprises a graphite block 7, Fig. 2, fuel pastilles 9 in bores 8 closed by plugs, and holes 11 and an annular passage 13 for coolant, and a reactor pressure tube 12 surrounds the element, a ductile layer 10 of the impregnating material being produced. The impregnating metal may be Al-Si, Mg-Si, Mg-Zr, Mg-Al or Zr-Be. The metal member may be made of Zircaloy-2, "Invar 40" (Trade Mark) steel, molybdenum or tantalum. The crucible of the autoclave may be made of pyrophyllite.