The Nevada Test Site (NTS) Use Committee met Tuesday morning, May 28, 1957, at Mercury, Nevada. This document provides a summary of the meeting.

A preliminary analysis has been made to compare the performance.of a ceramic ramjet reactor powerplant, such as described in General Electric Report No. XDC-56-5-81, with that of such a powerplant supercharged by a metallic-vapor-cycle compressor jet. Performance at sea level, Mach 2.5 is ·reported for the vapor-cycle compressor jet alone, for the ramjet alone, and for the compressor jet - ramjet combination. Results indicate that adding the compressor-jet as a supercharger for the ramjet provides an increase in specific thrust of about 20 percent over that of the ramjet alone, with an attendant increase in thermal efficiency of about 20 percent over that of the ramjet alone.

A number of coatings was investigated for protection of graphite against high-temperature oxidation and erosion. Well-sintered, well-bonded silicon carbide coatings were obtained by depositing elemental silicon on graphite, densifying, and sintering in CO at 1300 to 1400 deg C. However, the coatings were not perfect since complete protection was not offered against oxidation. A 75-15- 10 nickelchromium-silicon alloy sintered at 1100, 1200, and 130 deg C wet graphite very well, whereas coatings with high metallic luster were obtained at the higher temperatures. Fecral, alumina, and chromium-silicon-iron-aluminum alloys were deposited electrophoretically on graphite. Although excellent green coatings were obtained, sintered coatings were poor. The fecral coatings did not wet the surface, and the alumina coatings were brittle and non adherent indicating that a higher temperature was necessary. (For preceding period see KLX-10065.) (auth)

Progress is reported on the gross solubility of U in digestions of Mallinokrodt feed materials, studies of variables affecting U purity in a TBP hexane extraction cycle, low-acid flowsheet for TBP--hexane extraction process based on a 440 g U/liter in lM HNO/sub 3/ digest liquor, hacking studies in the pilot plant pumperdecanter system, recovery of U from residues from the dingot process, lowering the H level in dingot metal, forging of dingot bar stock, dingot extrusion, fubrication of UO/sub 2/ fuel elements, and the determination of H content of derby and ingot metal. (W.L.H.)

An apparatus is described in which crossed E and H fields will be used to separate high-energy charged particles of different masses. It is shown that use of coaxial geometry is expected to effect satisfactory separation within a considerably shorter system than would be possible in a parallel-plate system with a comparable separation criterion, A summary is given of the operational characteristics of a spectrometer now under construction.

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Fabrication techniques for producing dispersion fuel elements with cores of 30 volume per cent of UC, U/sub 2/Ti, U/sub 3/Si, or U/sub 6/Ni dispersed in Zircaloy 2 and 30 volume per cent of UC or UN dispersed in Type 18-8 stainless steel have been investigated. Roll-clad plate-type elements of all these compositions may be fabricated by powdermetallurgy methods in such a manner that good core-tocladding bonds and cores with uniform dispersions of discrete uranium- compound particles are obtained. From the standpoint of fabricability, elements containing UC in Zircaloy 2, UC in stainless steel, and UN in stainless steel are the most promising. The UN in stainless steel has the best corrosion resistance in 680 deg F degassed water; however, UC in stainless steel has the best resistance to corrosion in 700 deg F NaK. (auth)

The effects of pile irradiations on the physical properties and corrosion resistance of U-- Mo, U-- Nb; and U--Si alloys are reported. The dimensional stability under irradiation of the gamma phase U-- Mo and U-- Nb alloys is excellent; however, an isotropic volume increase of 4 to 6% per wt.% burnup may limit the ultimate fuel element life. Corrosion resistance of the gamma-phase alloys appesrs to be improved when subjected to s neutron field; this is attributed to an irrsdiation induced stabilization of the gamma phases. The U/ sub 3/Si alloy, on the other hand, suffered severe deterioration, particularly of corrosion resistance. Changes in electrical resistivity, hardness, mechanical properties, and crystal structure are presented and the mechanisms producing the observed changes discussed. (auth)

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The rates of growth of diffusion layers between U and Al and between U and AlSi alloy (eutectic composition) were studied and compared over the temperature range 250 to 55O deg C. Metallographic observation shows that the U-- Al reaction layers form three to five times as fast as the U-- AlSi layers over this temperature range. Sixty per cent of the layer growth takes place in the Al or AlSi alloy and 40% in U. (auth)

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A wide range of irradiation testing facilities and services are present at the Hanford Atomic Products Operation. A number of these facilities are described as a means of illustrating the testing equipment and techniques which are currently in use. (auth)

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