RRFM 2009 Transactions - European Nuclear Society

Fig. 5 Macroscopic cutting view (x 20) of the irradiated U-Mo multi-wire fuel
The amount of swelling was estimated by calculating the diameter changes between the
diameter of the fabricated fuel meat and the diameter of the irradiated fuel meat measured for
the picture Fig. 4. The amount of swelling was ~ 8.3% for the U-7Mo multi-wire fuel as shown in
table 2, of which the swelling was less than the swelling of U-7Mo/Al dispersion fuels.[7] Also it
was less than 8.3% for the U-7Mo-0.2 Si fuel.
Table 2. Fuel meat swelling of U-7Mo multi-wire monolithic fuel.
Diameter
of
fabricated
fuel
(mm)
Diameter
of
irradiated
fuel
(mm)
Area
fraction of
fabricatio
n
(%)
Area
fraction of
irradiated
fuel
(%)
Area of
fabricated
fuel
(mm2)
Area of
irradiated
fuel
(mm2)
Swelling
(%)
U-Mo
wire
1.95 2.11 36.8 40.2 11.95 14.13
Al 6.43 6.69 63.2 54.1 20.52 19.02
Interacte
d area
5.7 2.00
Total 32.47 35.15 8.3 %
The thicknesses of the interaction layers for the U-7Mo 4 wires are 35 , 54, 87, 88 μm
respectively. The thicknesses of the interaction layers for the U-7Mo-0.2Si wires are almost the
same at ~ 50 μm shown as Fig 6.
~53 μm ~38 μm
~46 μm ~46 μm
Fig. 6 Thickness of the inside interaction layers of the U-7Mo wire (left) and the U-7Mo-0.2Si
wire
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