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ANP QUARTERLY PROGRESS REPORT
TABLE 6.2 RESULTS OF OPERATION OF HASTELLOY B THERMAL-CONVECTION
LOOPS WITH VARIOUS FLUIDS
Hot-Leg Temperature Period of
Metallographic Notes
NaF-ZrF4-UF4 1500 325 1000 Rough surface; intergranular penetrations; subsurface
voids to 3 mils
1500 325 2000 Slightly rough surface; voids to a depth of 2 mils
1650 400 1000 Rough surface; most voids to depths of 2 mils or
less, but occasionally to 3 mils
1650 400 1000 Maximum attack to a depth of 2 mils; slight deposit
in hot leg
NaF-K F-L i F-UF4 1500 325 1000 Subsurface voids and intergranular penetration to a
depth of 2 mils; thin deposit in hot leg; intergronu-
lor attack in cold leg to a depth of 1.5 mils
Sad ium 1500 400 1000 Fine metallic crystals
drained while at 150OoF
1500 400 1010 Plugged by mass of fine dendritic crystals in hot leg
that probably formed in cold leg
TABLE 6.3. RESULTS OF OPERATION OF SPECIAL
ALLOY THERMAL-CONVECTION LOOPS WITH
NaF-ZrF4-UF4 (50-46-4 mole %) WITH A
HOT-LEG TEMPERATURE OF 1500°F
AI ~ oy Composition (wt X)
Ni Fe Cr Mo
76 7 17
76 14 10
76 14 10
76 19 5
76 19 5
83 7 10
83 7 10
74 10 6 10
74 10 6 10
*Leak developed in loop.
Operating
Time Attack
(hr) (mils)
1000
823*
1 ooo*
647
460*
1000
1000
1000
500
13
8
12
3
3
13
15
3
3.5
SODIUM-B ERYLLIUM-INCON EL
COMP AT IB I Ll TY
E. E. Hoffman
C. F. Leitten
Metallurgy Division
As one phase of the sodium-beryllium-Inconel
compatibility studies, a series of lnconel thermal-
* *
convection loops with beryllium inserts in the top
of the hot legs were operated. The inserts were -
hollow cylinders about 6 in. long with inside .-
diameters the same as those of the lnconel tubing
of the loop. The outside of the beryllium was pro- I
tected by an lnconel sleeve and was separated
from it by a 0.050-in. annulus filled with slowmoving
sodium. The loops were operated for 500
hr with h igh-pur ity sod i um at hot- leg temperatures
of 900, 1100, and 13OOOF. In none of these loops
was any attack found on the inside surface of the
beryllium, and the outside surfaces of the inserts
in the loops operated at 900 and llOO°F were
similarly unattacked. However, in the loop operated
at 13OO0F, the outside surface of the beryllium
insert showed widely scattered voids to a depth of
3 mils. All the beryllium specimens were darkened,
but no deposits were found by metallographic
exam i nation.
A summary of compatibility tests conducted by
two different methods is presented in Table 6.4.
In none of the tests was a layer deposited in the
cooler portions of the test system that could be
-
detected metallographically. In all the tests, however,
beryllium was found to be present on various
:,
sections of the lnconel tubes. Figure 6.1 shows
the distribution of beryllium around an lnconel
whirligig loop following a 270-hr test at a hot-zone
temperature of 120OOF and a cold-zone temperature
of 106OOF. Since the velocity of the sodium bath