Page 279 - 00. Complete Version - Progress Report IPEN 2014-2016

Nuclear Reactors and Fuel Cycle | Progress Report 279

gU/cm3 for the U3Si2-Al dispersion, which is
well placed around the world. Based on IPEN
previous experience in developing and man-
ufacturing dispersion type fuel, the objective
of this project was to promote an adjustment
to the current fuel manufacturing procedures,
allowing the incorporation of higher urani-
um concentrations to the fuel. The goal is to
increase the uranium concentration up to 4.8
gU/cm3 by using the U3Si2-Al dispersion, and
3.2 gU/cm3 with U3O8-Al. These concentra-
tions are the maximum possible to be incor-
porated into the fuel when adopting the dis-
persions technology.

The manufacturing process of the MTR type
fuel elements (U3Si2 uranium silicide type or
Figure 35.
U3O8 uranium oxide type) has two main stag-
es: the pressing of briquettes, which are the
IPEN developed and made available for rou- fuel meats, and the rolling operation for manu-
tine production the technology for manufac- facturing the fuel plates. The briquettes are as-
turing dispersion type fuel elements for use sembled in an aluminum frame with two alu-
in research reactors. However, the current fuel minum cladding plates forming a “sandwich”.
produced at IPEN allows the incorporation of The set is then hot and cold rolled to get a fuel
3 gU/cm3, by using the uranium silicide tech- plate. Figure1 illustrates the set ready for roll-
nology (U3Si2). Increasing the uranium con- ing and the final fuel plate fabricated. In this
centration of the fuel is interesting by the project, the meat compositions were defined
possibility of increasing the reactor core re- based on the maximum uranium density that
activity and lifetime of the fuel. It is possible can be incorporated into the dispersion, which
to increase the concentration of uranium in is internationally defined as 45 vol% for the fis-
the fuel up to the technological limit of 4.8 sile phase. For U3Si2-Al dispersions the max-

Figure 36.