Inert matrix fuel in dispersion type fuel elements

Main results of the development of dispersion type IMF at A.A. Bochvar Institute

“…In various reactor types under different irradiation conditions preliminary in-pile tests and post-irradiation examinations were carried out using prototypes of fuels and fuel compositions in which PuO 2 was substituted by UO 2 (Table 1) [3,5,[8][9].…”

“…Both aluminium and zirconium matrix fuel rod prototypes 250-1000 mm long clad in zirconium alloy E110 and fueled with UO 2 granules were successfully in-pile-tested under conditions VVER-440, VVER-1000 and RBMK without loss of tightness or volume changes [3,[8][9]. Aluminium matrix fuels reached the burnup of 100 MW d/kg U and the burnup of zirconium matrix fuels made up 60 MW d/kg U.…”

“…Under the action of capillary forces the molten zirconium alloy coats the fuel granules and the cladding and moves into the gaps between the fuel granules and the cladding to form so-called bridges which provides for the high thermal conductivity of the fuel meat. [3][4][5][6]. The second version is a fuel element with a heterogeneous arrangement of fuel [3][4][5][6].…”

“…[3][4][5][6]. The second version is a fuel element with a heterogeneous arrangement of fuel [3][4][5][6]. According to the third version a porous meat of zirconium metallurgically bonded to a fuel cladding is formed through which a PuO 2 powder is introduced [9].…”

“…Development of dispersion type IMF concept with metal matrix and metallurgical cladding -fuel bond IMF elements contain a small volume fraction (not more than 15%) of a fissionable element (PuO 2 ). This specific feature makes it possible to use as a IMF element dispersion type fuel elements with metal matrices that as distinct from the traditional pelletized fuel elements have a number of advantages [3][4][5][6]. They are a low temperature of a fuel centre, high irradiation resistance, feasibility of extended burnups (100 MW d/kg U and higher).…”