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ANP PRQ JECT QUARTERLY PROGRESS RQEO
times when high urani urn conc en tra tioris
are used.
A test was run in the tilting
furnace under standard conditions of
time and temperature with NaF-ZrF4-UF,
(50-46-4 mole %) that had been treated
with hydrogen after purification by
the norma 1 hydrogena tion-hydro fluor i -
nation method. Type 316 stainless
steel showed somewhat less attack when
subjected to the hydrogen-treated
material than when exposed to material
prepared in the standard fashion. The
Inconel tubes were found to be lightly
attacked (0.5- to 1-mil penetration)
when in contact with the hydrofluorin-
ated material, but they evidenced no
atthck when exposed to the hydrogen-
treated material. These preliminary
tests indicate that a final hydrogen
treatment of the fuel would be bene-
ficial. Additional tests are scheduled.
Temperature Dependence. Although
the immediate application of the
fluoride fuel NaF-ZrF4 -UF, (50-46-4
mole %) is to be limited t.0 a tempera-
ture of 1500"FJ some corrosion tests
under static conditions were performed
at considerdbly higher temperatures to
determine the temperature-dependence
of the corrosiveness of this fuel. As
the data in Table 11.5 indicate,
penetration of the Inconel by the
fluorides in these 100 hr tests in-
creased slightly, if at all, over the
ternperaturc range 800 to 1200°C.
It is interesting to note that
Inconel seems to lose weight at 1200°C
instead of gaining weight as is usual
at the lower temperatures. No expla-
nation for the behavior at high temper-
atures is suggested.
Ceramic Materials. Two specimens
of beryllium oxide blocks with approxi-
mate dimensions 0.25 by 0.25 by 0.50
in. were exposed t,o NaF-BeF2 (57-43
mole %) for 100 hr (24,000 cycles) in
the tilting furnace with the hot end
(beryllium oxide mechanically held at
hot end) at 800"CJ and the cold erld at
TABLE 11.5. CORROSION OF INIONEL BY NaF-ZrF4-UF4 AT TEMPERATURES PROI $B
- .I_
~. .
RUN NO.
13 2
800
1000
1100
1200
'a)Prerun analyses of fuel:
("Prerun analyses of fuel:
("Prerun analyses of fuel:
__ .......
...............
WEIGHT CHANCE
( mg/dm2/day 1
+4
+8
-1
+22
4-9
+12
0
+6
- 13
-31
._ .____
....
...
0.5 to 1
0.5 to 1
0.5 to 1
1 to 2
1 to 4
1 to 4
0.5 to 2
0.5 to 2
0.5 to 2
0.5 to 1
3000 ppm Fe, 980 ppm Cr, 230 ppm Ni.
720 ppm Fe, >20 ppm Cr, 135 ppm Ni.
340 ppm Fe, >20 ppm Cr, 580 ppm Ni.
....... ~
........
CHEMICAL ANALYSIS (ppm) .~
Fe
Cr
Ni
170
180
440
18 5
100
90
95
100
2 00
290
90
1860
2100
2700
3000
2600
980
1000
1030
61 0
20
45
20
20
20
20
20
20
75
110