The following progress report was compiled by the research and development division of the zirconium pilot plant. This report discusses two iodination and deposition runs that were completed as of August 20, 1951, as well as the third iodination run that uses a vaporizer condenser that condenses approximately 40 pounds of zirconium iodide.

Report discussing reaction of hydrogen with uranium in a range of temperatures and pressures. Experimental materials, methods and results are included.

This report covers the progress made on an intensive program to develop and evaluate UO2 as a possible fuel element for the PWR.

The following report presents neutron-flux measurements made with a concentric-cylinder element (Mark II) and includes axial, radial, and peripheral flux distributions.

From introduction: "As part of the program for improvement of graphite, the structural characteristics of graphite have been studied to determine the relation between physical and structural changes during irradiation."

The following report follows the studies of electroplating on uranium and concurrent metallurgical clodding.

Abstract: "The protection of thorium in hot water was studied. Copper electrocladding on thorium offers promising protection against hot water. The corrosion of thorium in 95 C water was reduced appreciably by a thorium phosphate film. The results of this abbreviated investigation offer a basis for the development of a method of protecting thorium at elevated temperatures in corrosive media."

The following report studies the dissolution of aluminum-canned thorium, providing results that suggest a dissolution cycle that permits the separation of the canned-slug components.

Abstract: "Aluminum electroplating was studied in a search for new methods of cladding uranium fuel elements. Uranium electroclad with 12 mils of aluminum over a 0.5-mil (or nickel plus copper) electroplate resisted corrosion for more than 100 hr in boiling water. This quality of protection was effected by hot pressing the electroclad uranium with 5.1 tons per sq in. for 5 min at 950 F. The electroclad uranium with hot-pressed samples paralleled those of later experiments with hot-pressed wrought aluminum claddings on uranium. In both cases, the uranium was electroplated with thin (0.5 mil) layers of metals to prevent aluminum-uranium diffusion, to aid bonding, and to assist in corrosion protection. This aluminum electroplating study helped to define the importance of the intermediate coating between the aluminum and the uranium, the effect of good bonds between the various layers, and the effects of hot pressing in protecting uranium with an aluminum cladding."

Abstract: "Aluminum-clad nickel-plated uranium is corrosion resistant in boiling water. Samples with intentional defects in the aluminum-nickel clodding layers, after testing for more than 300 hr. showed no sign of rapid failure. The study of electroplated metals on uranium for aluminum cladding has defined the effects of several processing variables on the corrosion resistance. The quality of the uranium and the quality of the aluminum-nickel bond were important. Heat treatment and vacuum outgassing of the nickel-plated uranium prior to aluminum cladding were beneficial, and minimizing the amount of air present in the hot-press assembly was desirable. Variation in the steps for electroplating on uranium did not affect the corrosion resistance of aluminum-clad uranium."

A report which describes a variety of methods for processing a low-grade sulfide concentrate from the Congo. This concentrate consists primarily of sulfides of cobalt, nickel, and iron, plus about 10 percent uranium, present principally as uraninite.

A report which intends to present an empirical formula, based on available experimental data, to correlate the thermal and electrical conductiviities of sirconium and sirconium alloys.

From abstract: "A Method has been developed for the uniform coating of graphite tubes with carbides of niobium, tantalum, and zirconium by thermal composition of their respective halide vapors."

The following report focuses on research made to determine whether the service performance of UO₂ fuel-elements cores for the PWR can be improved by certain ceramic or metal additions.

This report discusses the production of large-diameter zirconium crystal bars in a 16 inch diameter, Hastelloy B, de Boer unit in order to increase production efficiency.

From introduction: "This is the ninth monthly report, BMI-514, under Contract No. AT(30-1)-771 on "Zirconium Research and Development". The report covers the work period from September 15, 1950, to October 15, 1950. Work is continuing on the preparation of large-diameter zirconium crystal bars in the 16-inch-diameter de Boer unit. Crystal bars up to 1-5/16 inches in diameter and 8 feet long have been prepared in this unit."

From abstract: "This report describes the construction and operation of a mixer-settler pilot plant for the purification of mantle-grade thorium nitrate. The liquid-liquid extraction process utilized 30% tributyl phosphate - 70% 'Solvesso-100' as the organic solvent and nitric acid as the salting agent. Continuous steady-state operation of the equipment was demonstrated, with very good recovery of thorium."

Abstract: "Costs have been estimated for the production of uranium and pure thorium from monasite concentrates by a process involving (1) reaction of monasite with caustic soda, (2) dissolution of the hydrous oxides in hydrochloric acid, (3) separation from the bulk of the rare earths by hydroxide precipitation of thorium and uranium, and (4) purification by solvent extraction."

Report describing a method for recovery of high yields of thorium and uranium from monazite sand concentrates. Monazite is decomposed into hydrous metal oxides, which are dissolved in an acid. The solution is then separated into a precipitate, which seperates from thorium and uranium. An alternate separation method is evaluated.

From abstract: "Details are presented on the processing of monazite sand and on separating the rare earths from thorium and uranium. Solvent-extraction and ion-exchange techniques for purifying thorium and uranium are described."

A report which covers an investigation of techniques for producing hot-dip Al-Si coatings on uranium sheet. Also, the study is concerned with the effects of time and temperature of dipping on the intermetallic zone and its ductility.

From introduction: "At the request of WAPD, a study has been made of the effect of minor compositional variables on the corrosion behavior of uranium-molybdenum alloys in 650 F degassed water."

A report which provides procedures for sample decomposition and the determination of small amounts of uranium in the phosphate rocks and shales. Also, the cupferron and ether-extraction methods are discussed.

Abstract: "A quantitative method for the determination of individual rare earths in thorium down to a level of 0.05 ppm, is described. The procedure consists of a chromatographic cellulose-columns separation followed by a solution-type spectrographic determination. Values are given for the recovery of a number of rare earths using this combined procedure."