URANIUM ALLOY NEWSLETTER

Argonne National Lab. Annealing experiments of highpurity C --U alloys in the gamma region in an Ar atmosphere show that the metal is subject to decarbinization. Fourteen binary U--Pd alloys were prepared and examined. Pd solubility in gamma U is less than 1 wt.% at 890 deg C. Seventeen binary alloys of U-Ru were prepared and examined in the as-cast condition. The corrosion resistance after irradiation of U--Si alloys was tested. Homogeneous U- -Ta alloys have not been obtained. Th-rich U alloys were found to be more stable under irradiation than the best U alloys. The effect of heat treatment on microstructure is being studied as part of the effort to understand the effect of alloying on corrosion resistance in Ti--U alloys. Crystal and corrosion studies on U--Zr alloys are reported. Armour Research Foundation. Small ternary additions were found to greatly affect the transformation characteristics of U-- Nb alloys, and a hardness change was noted for this alloy. Preliminary data for U--Nb--Zr alloy demonstrated a relationship between the strained matrix and the physical properties of the alloy. Battelle Memorial Institute. Phase relationships between the intermediate delta phases of the U--Mo and U--Ti systems were conducted. U--Zr, U--Mo, and U--Nb alloys were evaluated for use as high-temperature reactor fuels. The kinetics of the betato-epsilon decomposition of Zr--U alloys are being investigated. The mechanism of aqueous U corrosion is being studied. Mallinckrodt Chemical Works. In the production of Nb--U alloy by co-reduction there was an indication of insufficient heat. Thermal boosters and a redesigned bomb for improving heat conservation will be investigated. National Bureau of Standards. Experimental work on the U-- Pt system is completed. Thermal analyses on U--Pd alloys did not show the U transformations present. Metallographic examination revealed an apparently singlephase structure. Thermal analysis data were collected for U--Ru and U--Rh systems. Attempts to prepare U--Sr alloys by high-frequency induction methods were unsuccessful. Nuclear Metals, Inc. Corrosion tests on Zircaloy2-clad U alloys were made. Sylvania Electric Products, Inc. Thermal cycling and mechanical propenties of U- rich alloys sufficiently stable to permit reactor operating temperatures in excess of 1200 deg F were studied. Mo--U alloys are the most stable toward alpha- beta cycling. Westinghouse Atomic Power Division. Transformation kinetics of the U-- Zr alloys were studied. Serrated stress-strain curves in U-- Zr alloys were studied. Alloys in the epsilon and gamma conditions as well as aged and prestrained conditions were studied from room temperature to 600 deg C. (F.S.