The thermophysical properties of Armco iron such as thermal conductivity, electrical resistivity, and Seebeck coefficient have been extensively investigated and reviewed up to 1000 degrees C. Few investigations of such properties have been made on high purity iron. If such a study is made using the same apparatus to determine the properties of two purity levels of iron, then several significant intercomparisons can be made which add meaning to data on a single material. The systemic errors for a single apparatus are the same, therefore comparison of a property of two similar materials is more significant. A comparison of the property changes with temperature and purity can show the effects of impurities on the mechanisms contributing to a property and allows prediction of the properties of iron as a function of purity. For these reasons a study was initiated on the high-purity iron for comparison to Armco iron.

The experimental details, mathematical models, and typical data for a rapid comparative method for thermal conductivity measurements are presented. The method consists of measuring the temperature change of a small silver sphere after it is brought in contact with a small disk-shaped specimen which was initially at ta higher temperature. This temperature change was calibrated in the range of 50 to 400 degrees C by making measurements on samples of know thermal conductivity. The accuracy of this technique was shown to be between than +-10% with a reproducibility of at least +-2.5%. Using known transport mechanisms for heat conduction in solids and the temperature dependency of the electrical conductivity, a means to judiciously extrapolate thermal conductivity data obtained between 50 and 400 degree C to high temperature is presented.

Grade CGB graphite is a nuclear graphite which is basically an extruded petroleum coke bonded with coal tar pitch. No carbon blacks are used and the low-permeation graphite is finished through a series of impregnations and heat treatments with a final heat treatment of all components to 2800 degrees C. A listing of the results obtained is given in Table 1. The results at 51 degrees C are considered questionable. There was a slight contamination of the 90% Pt 10% Rh-Pt thermocouples at 910 degrees C but it was not sufficient to doubt the validity of the 910 degrees C results. However, the results obtained at 1015 degrees C should be disregarded because of severe thermocouple instabilities. In addition, the electrical resistance of the core heater at 603 degrees C indicated the thermocouples had a -10 to -15 degree error which is sufficient justification to disregard the 605 degrees C data.

The components for the present aluminum clad, Al-Si bonded, internally and externally cooled (I & E), uranium fuel elements are composed of impact extruded cans and spire caps as shown in Figure 1. This type of component requires two impact extrusions; however, in December, 1957, J. E. Ruffin proposed another design of component in which there was only one impact extrusion. For this component, Figure 2, the spire was impact extruded as a part of the can.

The large scale application of Zircaloy-2 pressure tubes for structural use either in or out of reactor service, is without precedent. For more common materials, there normally are adequate data and long operating histories on which to base design and service limits. In the absence of such information for Zr-2, several investigative programs have been devised to provide much of the information from which design and service limits may be defined for Zr-2 pressure tubes. These investigations encompass in-and-out-of-reactor creep and stress-rupture testing, pre-and-post irradiation testing, and bust strength, as well as the effect of flaws or defects (from both fabrication and service origins) on burst strength and fracture characteristics. Already creep and stress rupture testing of unirradiated Zircaloy-2 is well advanced, and some experimental pre-irradiation burst testing has been carried out and will be extended rapidly as improved equipment becomes available. One irradiated KER tube sample has been burst tested and the requirement for post irradiation burst testing equipment have been defined.

The experiments described in this report were designed to explore the feasibility of precipitating plutonium from 35 percent TBP in Gulf BT using peroxide, fluoride, sulfide, sulfite, sulfate, cocalate, hydroxide, iodate and phosphate ions from anhydrous, dilute and concentrated aqueous sources.

The chromium-nickel-manganese alloys are a group of austenitic stainless steels which were developed during the Korean War to conserve nickel. These alloys are very similar to their corresponding 300 Series grades in mechanical, physical and corrosion properties. A portion of the nickel in the 300 Series grades has been replaced by approximately 2% manganese for each percent of nickel replaced. Two compositions, AISI 201 and AISI 202, are recognized as standard grades. Two other compositions, AISI 204 and AISI 204-L, have been produced in limited quantities to replace AISI 304 and AISI 304-L. Experience with the 200 Series steels indication they are every bit as good as the grades for which they were once alternates. In some shapes, such as rod and sheet, the cost per pound is considerably lower than the corresponding 300 Series grades.

Over the last decade, several computational methods have been developed and used to examine reactor flow transients caused by pump outage. The variations in system character which have been analyzed are sufficiently diverse that it appears worthwhile to compile them into a single report.

A method to determine the correction to Grüneisen's law corresponding to the effect of the electrons at high pressure. It is assumed that the lattice contribution to the pressure is small and that the equation of state of the solid can be approximated by results of the statistical Thomas-Fermi atom model for the electron pressure.

The object of this project is to conduct studies on the coating of metals and alloys by the gas plating process. Coatings to be studied consist of chromium on copper; alloys of nickel chromium on copper; molybdenum on stainless steel and Inconel; chromium on stainless steel and Inconel; and tungsten and molybdenum and their carbides on stainless steel and Inconel.

The technique of high-frequency titrimetry has been applied to the determination of thorium, uranium, sulfate, and free acid. In Part I of this report, the reproducibility of the method for the titration of standard solutions which contained 50mg of thorium in the absence of interferences is established. The coefficient of variation of the method, under these conditions, was found to be less than one per cent. In Part II, the effect of uranium on the high-frequency titration of thorium, as well as the application of the method to actual samples, is discussed. Uranium in a ratio of 5 to 1 to thorium can be tolerated. When the method is applied to the analysis of representative samples, the coefficient of variation is one per cent.

After two batches (~ 340 kg) of fluoride salt from the ARE were reprocessed, pilot plant operations were terminated because of a leak through which an estimated 780 g of uranium (as UF6) escaped. Of the 21 kg of highly enriched uranium in the feed, 93.12% was collected as UF6 product, 0.13% represented measured losses, and 3.72% was unaccounted for (leak). An additional 3.03% was reclaimed from NaF beds and equipment washes. The product met both chemical purity and activity specifications for product level UF6. Decontamination from fission products was essentially complete. A gross gamma D.F. was apparently limited by the low activity of the feed salt.

Limitations on the maximum temperature of the pile moderator have been imposed to prevent or control the gasification reaction of the graphite stack with the pile gas atmosphere. An uncontrolled reaction would cause a loss of structural strength, density, and thermal conductivity and would thus result in an unnecessary shortening of the effective operating life of the HAPO piles. Numerous studies have been made to define the rates of reaction of the pile stack with various components of the pile gas and the influence on these rates of various pile operating conditions. Based on these studies, maximum graphite temperature has been so restricted that after 10 years of pile operation the graphic stack has sustained less than 1% oxidation (based on recent experimental data). As pile power levels increased, the maximum graphite temperature has also increased and will increase still more as present and future power level programs are completed. In order to evaluate the effect on the graphite stack of the present programs, and to some extent determine the feasibility of future programs, a more realistic approach to the question of structural integrity and oxidation versus pile life is necessary. It is the purpose of this report to summarize …

Experiments are described which show that magnetic fields can exert a controlling influence on the operating characteristics of point contact transistors. The effect is especially evident when the transistor is operated in its negative resistance region. The frequency of an oscillator can be varied, or a switch made to trigger by applying a magnetic field to the transistor. Some applications of the principle are suggested; many more are evident.

Temperatures are given at which two liquid phases form in a synthetic homogeneous reactor fuel solution and its concentrates. The data show a two-liquid-phase boundary temperature of 332°C for the Particular HRT Fuel composition and a flat minimum temperature of 305°C for the initial solution concentrated between 300 and 329°C are presented to indicate solution stability in this temperature region. Some related comments on current HRT operations are given.

An annual report is given on the operation and costs of waste-disposal facilities at ORNL laboratories and operating buildings in the Bethel Valley area. The operations of the hot-chemical and metal-waste systems, the process-waste system, and the radioactive-gas-disposal system which utilized the 250-ft stack located in the Radioisotope area are discussed. The miscellaneous operations which include the SS (source and special nuclear) material control, SS material recovery, off-shift service for research divisions, water demineralization plant operations, and hydrogen liquefaction are included. However, the disposal of cooling water from LITR, off-gases from the Hot Pilot Plant, and the ORNL Graphite Reactor building are not covered by the report.

The circuits described herein and shown functionally in Fig. 1 are to be added to the HRT control circuit to provide control and protection for the revised HRT cooling water system. The circuitry will provide protection against excess pressure in the demineralized cooling water loop and cooling water activity, will initiate action to insure containment of activity in event of an explosion and will provide emergency cooling water from the tower basin when required.

A method was developed for calculating shield induced gamma radiation escaping through openings in a biological shield. The method was applied to the HRT and the results indicated that the contribution to the dose from induced activity in the HRT shield was around 0.1 r/hr and was insignificant in comparison to to other mechanisms contributing to the escape of gamma rays through shield openings.

A portable shield has been designed, developed, fabricated and shop tested to provide the HRT with a facility for direct dry maintenance operations. It provides temporary replacement for any one of the lower roof plugs and should permit many operations to be performed without flooding the reactor cell with water.

The effect of adding small quantities of fuel or poison to the HRT has been estimated using perturbation theory. The results have been reduced to a single relation and a set of graphs which make the estimation of added reactivity relatively simple. The perturbation theory results are compared with multigroup results and reasonable agreement is demonstrated; however, there is some question concerning the prompt neutron lifetime.

Sanderson & Porter have carried out a series of studies over the last four years which indicate that the pebble-bed reactor way be an attractive way to obtain low-cost power. At the request of the Atomic Energy Commission, two design studies have been carried out on this concept at the Oak Ridge National Laboratory. The first of these a preliminary design of a 10-Mw(t) reactor experiment, the PRRE, was initiated September 10, and a report on the study was issued November 1960. The second phase of the work, a conceptual design study of a 330-Mw (e) central station, was initiated November 1, and is the subject of this report.

Five uninsulated semipermanent freeze coils, series connected, can be frozen when submerged in 70 F water with a Freon-11 flow rate of 1.85 gpm at an inlet temperature of -40 F. The refrigeration unit of the HRT-CP is capable of delivering >3 gpm to a similar semipermanent freeze coil system located in Cell C. Therefore the number of F-11 risers required in Cell C of the HRT-CP can be minimized by series connecting this many semipermanent freeze coils where required.

A general program has been written to plot curves on the Oracle curve plotter. A description of the code and complete instructions for preparation of input tapes and operation of the code are given. The code tape is available from the Mathematics Panel or from the author.

The fact that material transport does occur under conditions of finite temperature difference in a flowing molten metal system was established. The rate mass transfer was thought to be either diffusion limited or solution rate limited. It is believed that the mass transfer of structural materials in Na or NaK systems is solution rate limited. The limiting process has not been qualitatively or quantitatively confirmed for the Inconel-Na or Inconel-NaK system. Increasing the maximum system wall temperature increases the amount of mass transfer, at least above 1300 deg F. The effect of the total temperature difference across the system on the amount of mass transfer was determined.