ORNL-2106 - the Molten Salt Energy Technologies Web Site

ANP PROJECT PROGRESS REPORT
Fig. 3.2.6. Specimens of Niobium After Exposure to Static Sodium at 1500'F in (a) an lnconel Capsule
and (b) a Type 304 Stainless Steel Capsule.
duced 17%.
Etched with 25% HF-25% H2S0,-50% H,O. 250X. Re-
0.3 mil thick, formed on the surface of both speci-
mens during the test. This layer, which is very
hard (-1180 VHN), is probably a niobium-nickel
alloy resulting from dissimilar-metal transfer, but
it has not yet been positively identified.
Vickers hardness traverses were made on the
as-received and as-tested specimens. The hard-
ness of the specimen tested in the type 304 stain-
less steel capsule increased (130 to 135 VHN)
during the test, whereas the hardness of the speci-
men tested in the lnconel capsule decreased (130
to 116 VHN). A correlation of the hardness values
with the impurity analyses indicates that nitrogen
is the major hardening agent. A niobium specimen
previously tested in argon at 1500OF for 2000 hr
showed a hardness increase from 127 to 168 VHN.
The impurities (H,O, H, N, and 0,) of the argon
used in the test totaled 130 ppm.
THERMENOL IN STATIC SODIUM
D. H. Jansen
Samples of Thermenol (82% Fe-15% AI-3% Mo)
cut from a piece of hot-rolled strip were corrosion
tested in static sodium for 100 hr at 1500OF. The
specimens were contained in AIS1 1035 steel and
type 430 stainless steel capsules. The specimen
tested in the AlSl 1035 steel capsule showed a
146
weight loss of 0.2295, and the specimen tested
in the stainless steel capsule showed a weight
loss of 0.07%. A slight roughening of the surface
occurred on both samples, Fig, 3.2.7. Neither the
type 430 stainless steel nor the AlSl 1035 steel
capsule was attacked during the tests.
STATIC TESTS OF ALFENOL
E. E. Hoffman
Specimens of Alfenol (84% Fe-16% AI), sub- ,
mitted by The Glenn L. Martin Co., were tested
under static conditions at 15OO'F in the fuel
mixture (No. 44) NaF-ZrF,UF, (53.5-40-6.5
mole %), lead, lithium, and sodium for 100 hr.
Since no Alfenol container tubes were available,
lnconel was used as the container material for
all the tests, The Alfenol specimens used in
these tests were \-in. cubes. The specimens
were placed in \-in.-OD, 0.035-in.-waII Inconel
tubes, together with sufficient test medium to
give 3 in. of liquid bath at the test temperature.
The specimen tested in the fuel mixture was
covered with black crystals and showed a 30%
weight increase. The crystals were analyzed and
found to be UF,. The specimen was attacked
throughout its thickness along the grain boundaries,
Fig. 3.2.8.