Hanford Laboratories Monthly Activities Report - December 1964

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HAN FORD LABORATORIES MONTHLY ACTIVITIES REPORT THIS DOCUMENT HAS BEEN SCANNED AND IS STORED ON THE OPTICAL DISK DRIVE HANFORD ATOMIC PRODUCTS OPERATION

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This report was prepared as an account of Government sponsored work. Neither the United States, A. Makes any warranty or representation, expressed or implied, with respect to the accuracy, com- ' pleteness, or usefulness of the information contained in this report, or that the use of any information, apparatus, method, or process disclosed in this report may not infringe privately owned rights; or Assumes any liabilities with respect to the use of, or for damages resulting from the use of any information, apparatus, method, or process disclosed in this report. As used in the above, "person acting on behalf of the Commission' includes any employee or contractor of the Commission, or employee of such contractor, to the extent that such employee or contractor of the Commission, or employee of such contractor prepares, disseminates, or provides access to, any information pursuant to h i s employment or contract with the Commission, or his employment with nor the Commission, nor any person acting on behalf of the Commission:

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HANF ORD L A BORA TORIE S P. R. No. Location Route Date Signature and Date HANFORD ATOMIC PRODUCTS OPERATION PRELIMINARY RE PORT This report was prepared only for use within General Electric Company i n the course of work under Atomic Energy Commission Contract AT(45- 1)-1350. Any views o r opinions expressed in the report are those of the author only. Excluded from automatic downgrading and de classification

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Force Report and Personnel Status Changes... Reactor and Fuels Laboratory Physics and Instruments Laboratory Applied Mathematics Operation Radiation Protection Operation Finance and Administration Operation Test Reactor and Auxiliaries Operation

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BUDGET AND COST SUMMARY December operating costs totaled $3, 485,000, an increase of $686,000 from the previous month. 4870 of the current control budget for FY-1965. Fiscal year - t o - date costs aggregate $17, 329,000 or Hanford Laboratories ' research and development costs for December compared with the previous month and the current control budget are shown Month Month T o Date Budget RESEARCH AND DEVELOPMENT 1. Reactor and Fuels Iron - aluminum additives to uranium fuel continue to appear superior to iron - silicon additives for inhibiting swelling both during irradiation and on post irradiation annealing. Uranium samples with other additives and combinations bf additives such as Fe-Al-Si, UC -UP, in varying con cent ra - tion, are being prepared and evaluated to develop improved compositions for swelling resistance.

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LiA102 and Li2SiOQ ceramic core targets irradiated in KER loops for 58 days released only a small fraction of the total gas generated when the capsules were opened after irradiation. Metallic Th-U fuel elements operating in the ETR at a maximum 2 te qp era ture of 500 C and a maximum surface heat flux of 700,000 Btu / h r - f t have reached 10,500 Mwd/ton exposure witha volume increase caused by solid state fission products of 1. 5 wt%. Experiments with an electrically heated test section representing the downstream half of an N - Reactor fuel column with interchannel mixing (as could occur at fuel element junctions) showed greater flow stability than tests without interchannel mixing. Higher tube powers may be permissible in N - Reactor than heretofore assumed. A literature survey was made to determine methods used at other sites t o establish boiling burnout safety factors used in the design and opera - tion of nuclear reactors. exist and that burnout safety factors stated for various reactors in the United States are not generally comparable. It was concluded that a standard method does not Additional data were obtained on critical flow of steam - water mixtures through pipe tees and elbows in the investigation of maximum discharge rates expected from reactor piping breaks.Efforts to predict the results of these tests by modifying correlations developed for flow from straight pipes have been partially successful, but additional work is needed t o allow definition of the critical pressure for pipe fittings other than straight pipes. Tests on AIS1 304 SS tubing were completed that indicate residual pickling acids can cause inter granular attack. No attack was found in samples exposed to charred vapor phase inhibitor vapor. control in the N - Reactor graphite cooling system has reduced the O2 concent ration in the coolant from > 15 ppm t o < 0.05 ppm.

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aluminum alloy dummies were irradiated for 30 days in neutral pH water at 260 C . Weight losses on fuel elements were 35 to 50% of the nickel at the inner Ni-A1 diffusion layer. Metallography showed considerable attack of the nickel terminating On dummy elements, the plate was nearly Nickel-plated aluminum has been exposed t o pH-10 water (NH40H) at 25 f t / sec and 330 Cfor 30 days and continues to show excellent corrosion resistance, much less than i n pH-10 lithiated water. 30 days are +7 to 15 m g / dm2 ; at neutral pH weight losses of 15 t o 45 substrate in NH40H solution at 300 C is comparable to that in neutral water and one-tenth that i n lithiated water. Weight changes after 2Corrosion of the aluminum Hydrogen pickup of Z irc alo y - 2has been studied overa wide range of oxygen-to-water partial pressure ratios at 400 C. Except at very low oxygen concentrations in high pressures team, hydrogen pickup is largely independent of oxygen to water vapor concentration ratios. Comparisons of the zirconium alloy corrosion and hydrogen pickup behavior in oxygenated and hydrogenated water can be made on the basis of Under fast neutron irradiation at flux intensities of about 1013 nv pre transition weight gains in hydrogenated water are lower by a factor of at least two and hydrogen pickup fractions greater by a factor of two than in water containing about 1 ppm oxygen (no hydrogen addition). The second of a series of controlled pressure - temperature uranium swelling capsules continues to operate successfully in are actor at 1000 psi and 575 C. The first capsule in this series operated at 1000 psi and 450 C . Several nickel - base alloys are being studied to determine the effect of irradiation and environment upon their mechanical properties.Fourteen

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tensile tests were completed at 650 C on Inconel 600, Inconel 625, Inconel 718, and Incoloy 800 specimens irradiated at exposures to8.3x lo2’ nvt decrease in ductility of all alloys when tested at 650 C (1202 F). These tests, as compared to room temperature tests, show a marked A creep capsule containing a n annealed AIS1 304 SS specimen was charged into the reactor this month. Test conditions are 30,000 psi stress Calibration tests to determine the spring constant as a function of crack length on the double cantilever beam specimen have been completed. These data are being used to determine the fracture toughness and ductilet o - brittle transition temperature of Z irc alo y - 2 and A-302B. Examination of optical micrographs of stress - ruptured specimens of Inconel X-750 indicates that transverse specimen sectioning provides better detail than does longitudinal sectioning. All micro cracks have been inter granular in nature, even with rupture tiines at 1350 F as low as 10 hr. In support of the ATR Gas Loop Project, the high pressure helium The system produced purification system of the Hanford model gas loop was activated during the period of November 1 6 through December 3, 1964. helium with less than 0. 1 ppm of the following: HZ, NZ, 02,CH4, CO, and The calc i a - stabilized zirconium tube oxygen monitor for the model gas loop has been modified to use air as a reference gas. Voltages observed showed dependence on oxygen content as predicted by the theoretical equation. The revised probe is now being incorporated into a portable instrument. Technical procurement specifications for the ATR gas loop chroma to - graph and total impurity analyzer have been prepared and have been sent to E basco Services,Inc.,for comments. It is expected that procurement of these instruments will start about January 4, 1965.

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Elevated temperature tensile tests are being conducted with high purity polycrystalline molybdenum t o establish the temperature at which the flow stress becomes independent of strain rate. this critical temperature between 900 and 1000 K. Tests to date have fixed A textured rod of unalloyed plutonium having a [ OZO ] axis was trans - formed into beta and measured and then transformed back to alpha and mea - sured. Dimensional changes are extremely anisotropic. Calculations indicate that differential contraction of the N - Reactor graphite bars under irradiation may fracture keys on the process tube blocks contractions i n the parallel directions could result in a gross vertical expansion of the moderator stack. Recent out - o f - reactor tests on full size blocks have confirmed both the mode of failure and magnitude of the stresses This would provide aramp that with continued differential Intensity of the Co60 source in the gamma irradiation facility i n the 3 7 3 0 Building has been m o r e than doubled. approximately 87,000 curies, making possible studies in a radiation field of The source now contains The radiation - induced contraction of conventional nuclear graphite s transverse to the extrusion direction of the bar a t 1050 to 1150 C ranges from0.3to 0.870, depending on the kind of graphite, after an exposure of parallel to the extrusion direction, ranging from2to 4.870. One ex peri - mental grade expanded slightly or contracted less than 0.570. Boron a ted graphite contracts at a high rate at 370 t o 540 C when exposed to a predominantly fast neutron environment. When exposed t o thermal neutrons, the material may expand at a rapid rate or contract, depending on the degree of dispersion of boron in the graphite.

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Out-of-reactor tests appear to confirm the postulate that PR TRs him rod sticking problems result from residual lubrication breakdown under radiation and / o r washoff in hot water, leading to galling between the lead screw and ball nut. core fuel element was successfully irradiated to a burnup of 1470 Mwd/to% with maximum fuel temperatures estimated to be above melting. Three additional high power density fuel elements were delivered to the PRTR. A fuel element designed to simulate conditions of extreme fuel cracking and t o allow possible impingement of molten U02 on the cladding has been irraTwo modified laboratory test capsules were extensively hydrided at 310 and 320 Cin the crevice region of a Vipac end cap. Essentially no hydride formation occurred in the s wage able end cap region at the opposite end of the longitudinal slit in one of the rods completed 16 days of operation i n the rupture loop with only minor activity release. small amount of core material when thermal cycled four times from 300 t o increment ally loaded swaged rod did not produce significant filter activity. Similar tests on an irradiated,increment ally loaded Vipac rod and an A heterogeneously enriched fuel element failed after an exposure of diam pellets with U02-8. 5 wt% PuOa packed powder peripheral enrichment. in the MTR. The failed rod consisted of 0.465-in.

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A vibrationally compacted U02fuel element with tube-in-tube geometry failed after a n exposure of 3x10l8fission s / c m .3 The underwater replacement of individual rods was successfully demonstrated in an irradiated simulated PRTR 19-rod cluster. A new technique for variable enrichment of packed-particle fuels involves the use of a helical plutonium wire, which permits continuous axial variation of fissionable atom concentration by s i m p l y changing the helix Repair of about 500 EBWR fuel rods will be accomplished by removing the cracked end and welding on a new end cap. Maximum exposures of the 10 i n - reactor (MTR) and 22 discharged EBWR specimens are 4.25 x lo2' fission s / c m ( 1 6 , 0 0 0 Mwd/ton of fuel) and 3 (11, 600 Mwd/ton of fuel), respectively. Fabrication of fuel rods for the Saxton Reactor is proceeding on No reaction was detected between PuOz and NiCr after heating a cer met showed no swelling upon exposure to air at about 1000 C, in contrast Four capsules containing stainless steel - 2 0 vol70 PuOa cer met pellets were fabricated for irradiation in the ETR. Extrusion of cer met fuel pins was continued using 93 t o 9670 dense spheroidized fuel particles. Metallographic examination showed that approx - im at ely 25% of the fuel particles fractured during extrusion, but no stringer ing was produced; that clad thickness control was esc ellen t ; and that a s - extruded dimensions will allow final sizing of fuel pins by swaging with an approximate OD reduction of 0.010 t o 0.015 in.

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A process for metallurgically bonding metal cladding and end caps to cer mets while simultaneously densifying the cer met has been dem mst rated on a variety of materials during recent months. Measurement of the dissociation pressure of Am02can proceed, with the confirmation that both Am02 and Pu02 are compatible with iridium sample holders at 1100 C, at which temperature both oxides earlier reacted PUN was prepared by carbon reduction of Pu02under 600 m m of A Pu-31. 6 at. 70 Z r alloy w a s hydrided and subsequently nitrided to forma single phase (Pu,Zr)N. Modification of the MRC high temperature X - ray diffraction equipment is nearing completion t o allow operation at temperatures up t o 2200 C. Electrical resistivity and Seebeck emf of U02 were measured, inreactor, throughout the range between ambient temperature and 1800 C . 2. Physics and Instruments tially complete. Some two-dimensional analyses were made on the previously analyzed Tho2 fuel verifying the validity of assumptions made in those analyses. experiments for determining conversion ratios of coproduct fuel are in progress. Preparation of exponential experiments and N - Reactor irradiation Detector and circuit modifications were made to aPu239 liquid sample counting system which improved sensitivity to1g / liter. Enrichment of a s - received N - Reactor fuel billets is being checked with a recently developed tester which has a sensitivity of 40,000 cpm per 1%change

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A new test was successfully used to in sure melting of the b raze wire in a group of TIG b razed N - Reactor fuel elements being fabricated for Critical it y experiments on aPu02 - plastic assembly with various composite reflectors,sub critical neutron multiplication measurements on an array of Pu02 powder incans, and exponential pile experiments with enriched uranium tubes in light water,were performed that provide data in support of plant critical it y problems. The effect on reflector savings of positioning neutron absorbing materials between a hydrogenous reflector and aPu02 - plastic core was determined from critical experiments. the effect of boron, and gadolinium in thin stainless steel plates, and cadmium sheet.Data were also obtained for the relative reflector savings of lead as opposed to …