METALLURGY DIVISION ANNUAL PROGRESS REPORT FOR PERIOD ENDING SEPTEMBER 1, 1959

7 = 9 9 9 9 7 7 7 = 9 9 9 95 : > @ 9 ; 5 8 @ = K : . ighpurity Nb deformed by impact or slow compression at - 196 deg C. An apparent phase transformation was detected in high- purity Ga deformed at 4.2 deg K. The specific heat of the group IV-A metals and alloys of Zr-In and Zr-Sn were measured from 1.2 to 4.5 deg K. In the Zr-rich portion of the Zr-Ga phase diagram, the alpha / beta phase boundaries of Zr are depressed by additions of Ga and the beta phase decomposes by a eutectoid reaction. The Cd pressures of alpha - and beta - Zr alloys containing 1 to 11% Cd were measured between 1090 and 1325 deg K. Crystal structures of several unreported transition-metal fluorides, rare-earth hydrides and nitrides were determined. Progress in the study of phase transitions in beta -quenched Zr-Nb alloys aged below the eutectoid temperature is reported. A high-temperature investigation of the order-disorder phase transition of a Cu31 at.% Au alloy has revealed an intermediate periodic antiphase condition. A previously described x- raydiffraction technique for the measurement of the thickness and strain of thin oxide films was applied to a series of five Cu/sub 2/O films grown on Cu single crystals. A new x-raydiffraction method for measuring film thickness, based on the integrated intensities of the Bragg maxima, is shown to agree very well with the thickness as determined from the line-shape analysis. A determination was made of the influence which electrostatic interactions with neighboring ions have on the energy n yields pi transition in the nitrate ion. Some information on the behavior of solute species in dilute solutions of Bi in BiCl/sub 3/ was obtained from absorption spectra. Studies of the gaseous oxidation of Nb and Zr in the 0RnL. Graphite Reactor indicated that neutron fluxes of approximately 10/sup 12/ nv had no effect on the oxidation processes for these two metals. A variety of new techniques was applied to the study of the oxidation of Ta. Efforts to Brow macroscopic single crystals of ceramic-type materials were initiated. HRP Metallurgy. An intensive study of the effects of fabrication variables on the anisotropy of mechanical properties and the preferred orientation in Zircaloy-2 is reported. The transformation sequence study of the Zr-Nb-X alloys is reported. A detailed macro- and micro-examination was completed on samples and debris removed from the core vessel of the Homogeneous Reactor. The fabrication of Zircaloy-2 vessels is discussed. Type 312 stainless steel was found to be satisfactory barrier material in making tube-to-header welds in Inconel-tane 347 stainless steel composites. Reactor Metallurgy. Examinations were made of low-alloy and stainless steels following their exposure to impurities outgassed by graphite. A three-phase out-ofpile corrosion test program is continuing in order to evaluate the behavior of Inconel and INOR-8 in contact with fluoride salt mixtures in terms of such variables as time, temperature, and flow rate. Inconel and INOR-8 specimens carburized in the Na- graphite system show an appreciable decrease in their room-temperatare ductility. The nickelbase Coast Metals Nos. 52 and 63, the 82 Au-Ni, and pure copper brazing alloys show no attack when subjected tc fuel 130 for 100 hr at 1300 deg F. It was found that LiF-BeF/sub 2/- UF/sup 4/ (62-37-1 M%, fuel 130) would precipitate part of its U as decrease in their room-temperature ductility. The nickelUO/sub 2/ when in contact with graphite at 1300 deg F. Graphite grades GT- 123, 186, CCN, R-0013, AGOT, and TSF were exposed in 100-hr static permeation tests to molten fluoride salts at 1300 deg F under a 150-psig pressure. Hotpressed UO/sub 2/ pellets show no corrosion after being subjected to pure lead, pure bismuth, the 55 Bi-45 Pb eutectic alloy, and the Pb-0.69 1.i alloy eutectic in separate tosts at 650 and 750 deg F. The reactions of type 304 stainless steel with CO and CO/sub 2/ were studied at high temperatures. Studies were made to determine the feasibility of fabricating a triplex heat exchanger tube made up of two concentri