Search Documents

By F. Forscher

Pronounced porosity, decreasing with distance from the fracture surface, is found in the necked region of tensile specimens tested at room temperature or liquid nitrogen temperature. A hydrogen solution treatment followed by a quench prevents pore formation in tests at —196°C, but has little effect on tests made at room temperature. Reduction of area values at —196°C are strikingly improved by the same treatment, but show no improvement in room temperature tests. The experimental results support the hypothesis that strain-induced porosity results with hydride initially present or, in material containing less than 50 ppm H, with hydride precipitated by strain aging. ZIRCONIUM'S advent as an engineering material in nuclear reactor construction has brought forth many investigations concerned with the properties of this metal and its alloys. Some attention has been given to the ductility of the metal.1, 2 Particularly, the effect of hydrogen on the impact strength was noted," indicating a pronounced dependence of ductility on the hydrogen content and its distribution in the metal. Micro graphic:' and X-ray diffraction studies' have shown that a precipitated hydride phase causes embrittlement in zirconium,' which implies a distinctly different mechanism from that causing hydrogen embrittlement in steels."-' In the latter case, it is assumed that atomic hydrogen diffuses to rifts, where it forms molecular hydrogen under such internal pressures that it causes the rifts to enlarge, leading to fracture. Thermo-dynamic studies of the Zr-H system8, 9 also indicate that the internal pressure of molecular hydrogen would be too low to cause any damage to the zirconium at room temperature, and the formation of a zirconium hydride (d phase) is favored." It is noteworthy that this phase has a face-centered-cubic structure and nearly 18 pet larger molar volume than close-packed-hexagonal a-zlrconlum' Other features of the ductility of zirconium are the absence of a typical cup-cone failure upon tensile testing, a pronounced strain-induced porosity in the necked region of a tensile bar, Fig 1, and the associated spongy appearance of the fracture surface A tremendous improvement in ductility at liquid nitrogen temperature can be observed following a heat treatment that retains the commonly present quan- tities (10 to 50 ppm) of hydrogen in solution. Such tests show a typical cup-cone failure and the absence of strain-induced porosity, Fig. 2. The present paper reports results of an investigation into the causes of strain-induced porosity in zirconium. Room temperature tensile fractures of mild steel, aluminum, and titanium have also been examined for strain-induced porosity. In each case porosity could be detected, but the amount was orders of magnitude less than was found in zirconium. Of the three metals, titanium showed the strongest effect. Material, Specimens, and Preparation The greater part of this investigation was done on Westinghouse crystal bar zirconium, are-melted, forged, and hot-rolled. Chemical analyses of the hot-rolled plates are given in Table I, along with those of the Foote crystal bar zirconium used in this work. The specimens were machined from the hot-rolled plate (1550°F) of 1/2 in. thickness and subsequently heat-treated according to one of the treatments shown in Table IS. All specimens were machined round, the longitudinal axis in the rolling direction, with a gage

Jan 1, 1957

By P. Chaudhari, Michael B. Bever

The heat of solution at infinite dilution of selenium in bismuth, the heat of mixing of selenium and bismuth, and the limit of solubility of selenium in bis~rzuth have been determined at 573, 623; and 663°K by metal solution calorimetry. The heat of forrrzation of the compound Bi2Se at these temperatures has been determined from the heat effects associated with the precipitation of the compound from a saturated solution oj selenium and bismuth. The published information on the thermodynamic properties of the system Bi-Se is limited. The heat of solution at infinite dilution of selenium in bismuth at 623°K has been measured.' The heat of formation at 273 K1 and room temperature2 and the heat capacity at 80 K3 of the compound Bi2Se3 have been reported. An estimate of the heat of formation of the compound BiSe at room temperature has been published.2 Information on the phase relations in the system Bi-Se is available.' In the investigation reported here the following quantities have been determined at 573", 623", and 663°K: 1) the heat of solution at infinite dilution of selenium in bismuth, 2) the heat of mixing of selenium and bismuth in bismuth-rich solutions, 3) the limit of solubility of selenium in bismuth, and 4) the heat of formation of the compound BizSe. These quantities were determined by the addition of selenium to bismuth-rich solutions in a metal solution calorimeter. The determination of the heat of formation at the tem- perature of the calorimeter bath involved the precipitation of the compound from a saturated solution in the calorimeter. 5,6 This method differs from that commonly used which requires the addition of the compound and of a mechanical mixture of its components and yields the heat of formation at the temperature from which the additions are made (273 K EXPERIMENTAL PROCEDURE AND CALCULATIONS The solution calorimeter has been described in detail.' Pure bismuth (99.999+ pct) was used as the bath at the start of a run. The calorimeter was calibrated with small amounts of bismuth added from 273°K; the differences of the heat contents of bismuth at 273°K and the temperatures of the baths are listed in Table I. After the calibration, additions of hexagonal selenium (99.999+ pct) were made. Loss of selenium by evaporation was negligible. No unusual experimental difficulties were encountered.9 The differences in the heat contents10 of selenium at 273°K and the temperature of the bath, listed in Table I, were subtracted from the measured heat effects to give the "adjusted heat effects". The methods by which the heat of solution at infinite dilution, the

Jan 1, 1968

Jan 1, 1914

By N. F. Fiore, M. C. Mangalick

DISLOCATION damping in single crystals is orientation dependent.&apos; If dislocations are distributed uniformly over all the slip systems in a crystal, and if each dislocation contributes identically to the damping process, then a damping loss or decrement 6 arises. In fact, however, for a crystal of axial direction (hkl), dislocations on certain slip systems are oriented to make a larger contribution to the damping loss than are dislocations on other slip systems. Thus the measuring damping, 6 (hkl) is proportional to an orientation factor (hkl), which weights the ability of each slip system in the crystal to contribute to the total damping. If it is assumed that dislocations are distributed uniformly on all slip systems, then for a given orientation of an fcc crystal this factor is determined2,3 by the three nonzero elastic constants Cll, C12, and C44 and the density p. In this communication measured values of elastic constants for two Fe-18Cr-Ni alloys are reported, and the dislocation damping results on two different orientations of each alloy are analyzed for orientation dependence. Elastic constants were determined by measuring the ultrasonic velocities of one longitudinal and two shear waves in (110) direction of the fcc crystals.4 Variation of velocities with the change in orientation is very small for (110) orientation,3 and so this direction is ideal for orientation factor and comparative damping measurements. Experimental Procedures. The nominal compositions of the alloys studied are given in Table I. These alloys were vacuum-melted and vacuum-cast from high-purity materials at U.S. Steel Applied Research Laboratories. The single crystals were grown by the modified Bridgeman technique. The specimens were homogenized at 1350°C for 20 hr, cut to shape and size with a spark cutter, and then annealed at 1100°C for 20 hr prior to use. In the KHz frequency range, the Marx composite piezoelectric oscillator was used to obtain the damping. The ultrasonic pulse technique was used to measure the ultrasonic velocities and the attenuation in the MHz frequency range. M.c.mANGALICK,-- StudentMemberAIME,formerly Research Assistant, University of Notre Dame, is now with Casting Laboratory, Chase Brass and Copper Co., Cleveland, Ohio. N. F. FIORE, Associate Member AIME, is Assistant Professor, Department of Metallurgical Engineering and Materials Science. University of Notre Dame, Notre Dame, Ind. This communication is part of a Ph.D. thesis presented by M. C. MANGALICK to the Graduate School of the University of Notre Dame. Manuscript submitted May 20. 1968. IMD Elastic Constants. Table I gives the values of the ultrasonic velocities. Values of C11, C12, and C44 calculated from these velocities are also given in Table I, and it is evident that there is very little variation in C11, C12, and C44 with nickel content. This slight variation may be attributed to inaccuracies in velocity measurements and practical differences in the orientations of the specimens. For example, in B the time interval for vl was 2.4 ± 0.05 sec giving an error in v1 of 0.235 x or 0.005 in. per sec. The elastic constants obtained by pulse technique were tested by calculating E<110>, Young&apos;s modulus for the (110) direction, from the equation: This value was compared with the value computed from the resonance bar measurements in which where fr is the resonance frequency and I, is the length of the specimen. In all cases, the values calculated from the ultrasonic velocity measurements

Jan 1, 1969

By R. C. Nelson, T. L. Weaver, A. I. Michals

This paper describes the design and performance of an apparatus for making continuous nondestructive resistance measurements throughout a spool of fine wire. Highly reproducible results on clean and graphite coated tungsten and rnolybdenum wires from 1 to 9.5 mil are presented. A linear relation between resistance and wire weight (per standard length) was obtained on clean wires, but only on those coated wires with very uniform coatings. Results indicating a correlation between tensile strength, hardness, and resistivity are reported. THE increasing demand for greater uniformity in fine tungsten and molybdenum wires destined for use as mandrels, grids, and coils in radio tubes and as filaments in light bulbs has rendered inadequate the standard (sampling) approach to the control of wire diameter and other physical properties. This ap-

Jan 1, 1961

C. H. MATHEWSON, Chairman SAM TOUR, Past-chairman W. A. SCHEUCH, Vice-chairman T. S. FULLER, Vice-chairman W. M. CORSE, Secretary-Treasurer 810 Eighteenth St., N. W. Washington, D. C. Executive Committee J. L. CHRISTIE ARTHUR PHILLIPS E. H. Dix, JR. GUY C. RIDDELL W. M. PRIRCE J. WALTER SCOTT&apos; A. J. PHILLIPS&apos; H. M. WILLIAMS EL M. WISE

Jan 1, 1932

By Walter Miller

Construction of new large refineries was small in 1937, but extensive modernization and expansion of existing plants were made, bearing out the observation of the Bureau of Mines that the trend is strongly toward fewer and larger refineries. Building the first large combination skimming and cracking unit of 20,000-bbl. capacity was a startling achievement four or five years ago, but it has been exceeded many times since, and at least four units with a capacity of 30,000 bbl. or more were contracted for during 1937, as well as many other units of smaller but still substantial capacity. Installation of polymerization plants for producing high-antiknock blending naphthas from refinery gases progressed at an accelerated rate in refineries affording sufficient raw gas to make the use of the process profitable. The total productive capacity of polymerization units built and contracted for in the United States is now about 25,000 bbl., equivalent to the gasoline production from approximately 55,000 bbl. of crude oil a day. Octane Fuels Also utilizing refinery gases—the butylene fractions in particular—the plants for manufacture of iso-octane increased in number to such an extent that the combined capacities will enable the air forces of the United States shortly to go entirely to the use of 100-octane fuel, indications being that the Army will reach that position in 1938, with the Navy not far behind. Commercial air-lines are expected to take advantage of the greater power of high-antiknock fuels to gain the increased power and increased pay loads possible with their use. Work done on producing fuels with octanes beyond the 100 point has recently been reported, and their production can be expected, although at high cost, when the economics of the situation justifies and engines capable of utilizing them efficiently are available. In the field of motor fuels, important work was reported to the A.P.I. at its annual meeting, on the effect of altitude on antiknock requirements

Jan 1, 1938

By C. E. Ells, A. Sawatzky

The effect of neutron irradiation on tensile properties of the Zr-2.5 wt pet Nb-0.5 wt pet Cu alloy has been evaluated for integrated neutron fluxes up to 3 x 1020 n per sq cm (E > 1 Mev). Specimen temperature during irradiation was normally 300°C. The material was studied both in annealed and in quenched and aged conditions. When the alloy (fab-ricatedfrom sponge zirconium) is quenched from a temperature =40°C below the a + ß/ß transformation and aged 6 hr at 535oC, neutron irradiation up to the maximum studied has little effect 071 reduction in area, although there is a drop in uniform elongation and the yield strength is increased by = 25 pct. Conversely, irradiation of the alloy in an annealed condition can result in much greater changes in properties, with yield-strength increases of up to 200 pet. The dose dependence of irradiation hardening obeys the saturation equntion proposed by Makin and Minter to explain hardening in copper and nickel: Act = C[1 - exp(-Døt)/1/2 A rnodel is proposed to explain the effect of niobium content and metallurgical condition on irradiatiotz behavior. THE Zr-Nb alloys form a class of material susceptible to marked strengthening by quench and age heat treatment. With niobium concentrations as low as 2.5 wt pet, strengths can be developed which are double those of annealed zircaloy-2.1 Since the neutron-capture cross section of the Zr-2.5 wt pet Nb alloy is nearly identical to that of Zircaloy-2, significant gains in power-reactor neutron economy could be obtained by replacing stressed in-reactor components of Zircaloy-2 with the heat-treated Zr-Nb alloy. When the solution heat-treatment temperature is in the high (a + ß) phase, then the tensile properties of the quenched (and aged at 500°C) material have been shown to be relatively insensitive to neutron irradiation.1-3 Addition of small quantities of copper to the binary Zr-2.5 wt pet Nb alloy gives a useful reduction to the corrosion rate in air and carbon di- oxide,&apos; and a ternary alloy of composition Zr-2.5 wt pet Nb-0.5 wt pet Cu was chosen for one component in the Douglas Point Reactor. This application utilizes both the corrosion resistance to a moist air-carbon dioxide environment and the strength developed by a quench and age heat treatment. By suitable choice of solution heat treatment and aging temperatures, tensile properties of the ternary alloy can be made nearly identical to those considered as optimum for the binary alloy. One effect of the copper addition, however, is to give marked changes in the aging kinetics of the alloy.&apos; For this reason, it appeared that neutron irradiation might promote overaging in the ternary alloy, particularly at the elevated service temperature (=300°C). This paper describes the effect of neutron irradiation on the tensile behavior of the Zr-2.5 wt pet Nb-0.5 wt pet Cu alloy in several metallurgical conditions pertinent to its use as a reactor material. The metallurgical conditions included those for which aging occurs in the unirradiated material, and fully annealed conditions for which a higher degree of thermal stability could be expected. 1) EXPERIMENTAL Two batches of alloy were used, both made from sponge zirconium. The fabricator&apos;s analysis of principle constituents showed no significant difference between the two batches, Table I. The rod material was rolled to 1.5 in. diam, and then swaged to final sizes of 0.5 to 0.375 in. diam at nominal temperatures of 785" and 625°C for the AM and AS batches, respectively. Subsequent hydrogen analyses at CRNL confirmed that the hydrogen concentration of the as-received rod was indeed <20 ppm. However, it was found that the (a + ß)/ß transus for the AM material was approximately 25°C lower than that of the AS material, indicating rather more difference in oxygen concentration than given in Table I. Except for a small difference in yield-point behavior, the tensile prop-

Jan 1, 1965

By W. F. Rogers, J. A. Stewart, P. J. Kalish, E. O. Bennett

Detailed descriptions are given of materials, apparatus and the experimental procedure used to study the effect of bacteria on sandstone permeability. The factors affecting permeability during injection of bacterial suspensions which have been investigated are: (I) concentration of bacteria; (2) core permeability and median pore size; (3) species of bacteria, mode of aggregation and relative size; (4) injection rate or pressure differential; (5) mean pressure; and (6) depth of penetration of bacteria. The investigation demonstrated that bacteria cannot reduce core pertneability to zero and that their effect on permeability is subject to definite limitations. Remedial or permeability restoration studies also were made. Acidization in combination with reverse flow war found to be an effective method for restoring permeability In cores partially plugged with bacteria. The relationship between the bacterial quantities in the laboratory tests and those found in field operations is discussed. The linear laboratory flow data have been translated into terms of field radial systems; these data indicate the most practical methods of maintaining injection rates in the presence of bacteria are to increase injection pressures or hydraulically fracture the formation. INTRODUCTION It has long been known that various bacteria flourish in the above-ground components of oil field water-injection systems. The presence of these bacteria has led to the suspicion that they might enter into the causes for reduction of injection well permeability, but only recently has an attempt been made to describe the effects quantitatively.1 Biocides are used in many cases without a firm knowledge as to whether the bacteria are killed, or if they are, whether the dead cells affect formation permeability. This project was undertaken as part of a study to determine the effect of bacteria, residual oil and precipitated solids such as iron sulfide or calcium carbonate on the permeability of sandstones and to learn whether any of these materials adversely affect brine injectivity in secondary recovery or disposal operations. This report deals with that portion relating to the effect of bacteria. MATERIALS CORES Three different permeability ranges of Berea sandstone cores were used in the study. The range of initial, absolute brine permeabilities kj were: high — 278 to 400 md: medium—130 to 162 md; and low—17.7 to 48.3 md. The permeability data for the cores used in the tests are included in Table 1. All cores were cut to a nominal 1 in. diameter. Following air permeability determinations, they were molded with an epoxy resin in 1.5 in. ID aluminum sleeves. The sleeves had drilled and tapped holes for intermediate pressure connections along the length of the cores. After molding, the high- and medium-permeability cores were trimmed to 4 in. in length and the low-permeability cores to 2 in. These lengths resulted in pore volumes of approximately 10.9, 10.4 and 4.4 ml, respectively, for the high-, medium- and low-permeability cores. Pressure-transmitting channels were drilled through the plastic into the core proper, using the sleeve holes as drill guides. Width and depth of channel penetration into the core proper were approximately 0.03 in. and 0.05 in., respectively. Three pressure taps were used with all cores; for the high- and medium-permeability cores the taps were spaced 1 in. apart; for the low-permeability cores the taps were spaced 0.4, 0.8 and 1.2 in. from the inlet end. Pore size distributions were calculated from restored-state capillary pressure curves for representative cores in each of the three permeability ranges. In each case the pore size range with the greatest percentage of the pore space included the very small pores up to 0.5 micron in radius. The median pore radii were in the 5.5 to 6 micron range for the high-permeability cores; in the 4.5 to 5 micron range for the medium-permeability cores; and in the 3.5 to 4 micron range for the low-permeability cores.

Jan 1, 1965

By AIME AIME

IN times of stress nations pick strong men to lead them. Similarly the Coal Division selected forceful Larry A. Shipman, fuel engineer for the Southern Coal and Coke Co., Knoxville, Tenn.. to lead it through the year 1945. He was born in Indianapolis May 13, 1891. Following graduation from a technical high school in that city Larry began his fuel career approximately 35 years ago attached to one end of a scoop shovel, firing locomotives for the Pennsylvania Railroad. At the end of two years he transferred to the New York Central Lines and held these jobs successively: locomotive fireman, engineer, fireman instructor, supervisor of instructors, and fuel engineer.

Jan 1, 1945

By L. E. Tanner

A study was made of the transformation kinetics of the commercial titanium-base alloys, Ti-2.5Al-16V and Ti-4A1-3Mo-1V, using two different heat treatment cycles: 1) step-quenching to aging temperatures from a ß solution anneal and 2) water-quenching from an a+ß solution anneal followed by reheating to aging temperatures. Metallographic examination and hardness testing provided the major portion of the data, while electrical resistivity, dynamic elastic modulus, and X-ray diffraction techniques were also used to obtain critical or confirnzatory data. TTT diagrams were constructed from these results. The sheet alloys, Ti-2.5Al-16V and Ti-4Al-3Mo-lV, are of current interest to the Department of Defense. As an aid to the planning of their respective heat treatments, a program was carried out to determine the transformation kinetics of these alloys using ß and a + ß reference states. This paper presents the TTT diagrams constructed from data obtained by metallographic examination and hardness testing, as well as by X-ray diffraction, electrical resistivity, and dynamic elastic modulus determinations. EXPERIMENTAL PROCEDURE Materials—Sheets of the alloys were obtained from the producers in the "mill anneal&apos;&apos; condition and were tested prior to shipment to assure their meeting mill specifications. Chemical analyses were also supplied and are presented in Table I. Heat Treatment—The majority of the data presented in this study were obtained from hardness testing and metallographic examination. Sample coupons were cut from the alloy sheets and heat treated on a mass scale. The annealing cycles were operated in the following manner: 1) The ß solution anneals were carried out in a horizontal tube furnace with the bare samples protected by a dynamic helium atmosphere. Following this treatment, the samples were quickly transferred to lead, solder, or oil-bath furnaces for aging. After prescribed times at the various reaction temperatures they were water-quenched. 2) The second cycle simulated commercial practice, which requires the alloys be quenched to room temperature following the a + ß sotution anneal. This anneal was carried out in a muffle furnace with a dynamic helium atmosphere. The specimens were then reheated from room temperature to the reaction temperatures in lead, solder, or oil-bath furnaces, followed by water-quenching after prescribed times at these temperatures. Information concerning the critical temperatures of the alloys was obtained from the literature and solution treatments were based on these values. A summary of the solution annealing treatments is found in Tables II and 111. The aging temperatures for the (a - ß alloys ranged in 50°C intervals from 200°C (392oF) to approximately 50°C below the ß/a + ß transus in the first cycle and approximately 50°C below the a + ß solution temperature in the second. The transformations in these alloys were known to be rather rapid, and thus aging times started at 0.5 min and went to a maximum of 7000 min. Hardness Testing and Metallographic Preparation— Heat-treated samples were sheared and mounted in Bakelite with their cut edges exposed. After a flat surface was ground, the hardness was determined in Vpn on an Armstrong-Vickers machine utilizing a 20-kg load. Three to four impressions were made on each specimen. After this procedure, the hardness impressions were removed and the edge surfaces of the specimens were prepared for metallographic examination in the usual manner. The etchant was 20 pct HF and 20 pct HNO3 in glycerine. Electrical Resistivity—It has been shown that the isothermal reactions in titanium-base alloys can be followed by measuring the changes in e1etrical resistivity attending these transformations. As mentioned earlier, the reaction kinetics of a-ß alloys are rather rapid; thus, it would be expected that resistivity data obtained from these alloys would be more significant if measurements were made continuously at the respective aging temperatures. To accomplish this end a special apparatus, based on the current-potential principle, was assembled. Its design was derived from earlier devices constructed by Colner and zmeska1 4 and Levinson.5 The set-up provided for the heat treatment zof machined specimens (approximately 2 x l0-4in. in cross section by 3 in. in length) and the determination of their relative

Jan 1, 1962

Geological Survey of the State of Maine, Orono, Me. Joseph Conrad Twinem, State Geologist In the years 1837, 1838, 1839, Charles T. Jackson made three reports on the geology of Maine Reports were made in 1861-1862 by C. H Hitchcock entitled, respectively, "General Report on the Geology of Maine" and "Geology of Maine." These old reports are now out of print

Jan 1, 1933

PRESIDENTS DAVID THOMAS 1871 R W RAYMOND 1872-1874 A L HOLLEY1875 ABRAM S HEWITT 1876 T STERRY HUNT 1877 ECKLEY B COXE 1878 - 1879 WILLIAM P SHINN 1880 WILLIAM METCALF 1881 RICHARD P ROTHWELL 1882 ROBERY W HUNT 1883 JAMES C, BAYLES 1884-1885 ROBERT H RICHARDS 1886 THOMAS EGLESTON 1887 WILLIAM B POTTER 1888 RICHARD PEARCE 1889

Jan 1, 1923

THE Institute Committee on Industrial Relations, of which Robert Linton is chairman, held a meeting on Feb. 21, listed as one of the technical sessions of the annual meeting, at which reports of the sub-committees were presented. Following are abstracts of these reports. The Institute can furnish mimeo-graphed copies of the complete reports on Safety, Employment, Illness, Mental Factors, and Cripples in Industry. The supply of the other reports has been exhausted. A paper by George F. Kunz, which was presented at the same meeting, is printed here in full.

Jan 6, 1922

By Willard L. Hunter

Four solvent extraction systems were studied to determine their efficiency jor extraction and separation of tantalum and columbium. Aqueous feed solutions of varying HF-HCl concentrations and metal content were contacted with equal volumes of cyclohexanone, 3-methyl-2-butanone, and 2-pentanone and solutions of varying HF-H2S04 concentrations were contacted with equal volumes of 2-pentanone. One multistage continuous test was made in a polyethylene pulse column using cy clohexanone as the organic phase. In each system studied, columbium and tantalum purities in excess of 95 pct with respect to each other were obtained in single-stage tests at low acidities in the feed solution. Separation factors ranging from 1700 to 2400 were obtained when rising HF-HCl mixtures in the aqueous phase. Best results were obtained when a solution of HF-H2S04 was used as the aqueous phase and 2-pentanone as the organic phase. A separation factor in excess of 6000 was obtained in one stage with aqueous solution concentrations of 2 _N HF and 2N H2S0,. When acid concentrations were increaszd to 52 HF and 10 _N H2S0,, 99.9 pct of the tantalum and 98.2 pct of the columbium initially present in the feed solution were transferred to the organic phase. The separation of columnbium and tantalum obtainable by means of the solvent extraction systems presented in this paper was found to corn -pare favorably with other systems, including the HF-H2SO4-methyl isobutyl ketone system currently used by most producers for the extraction and separation of these metals. TANTALUM and columbium are always found together in minerals of commercial significance, although the proportion of the two metals in ores varies within broad limits. Columbium is estimated to be 13 times more abundant than tantalum. Five methods generally employed for the separat:ion of these metals are: 1) fractional crystallization (the Marignac process),2 2) solvent separation, 3) fractional distillation of their chlorides, 4) ion exchange, and 5) selective reduction. Of these methods, the one currently used by industry to the greatest extent is that of solvent separation. One of the early technical developments in solvent separation of tantalum from columbium was reported by the Bureau of Mines: the HF-HC1-methyl isobutyl ketone system; data were presented for both laboratory and pilot-plant experimentation.3 Of twenty-eight organic solvents tested for their ability to extract tantalum from an HF-HC1 solution of columbium and tantalum, 3-pentanone (diethyl ke-tone), cyclohexanone, 2-pentanone, and 3-methyl-2-butanone were chosen for further study. Data on the HF-HC1-diethyl ketone system has been published4 and data describing the use of cy clohexanone, 2-pentanone, and 3-methyl-2-butanone as the organic phase are included in this report. RAW MATERIAL The source of tantalum and columbium oxides for this study was (&apos;Geomines" tin slag from the Manono Smelter, Cie Geomines, Gelges, S.A., Congo. In order to extract the valuable Ta-Cb content, the slags were carbided, chlorinated, and the sublimate from chlo-rination was hydrolized and washed free of chloride with water. The washed material was air-dried and stored in a stoppered container. Throughout the paper, "feed material" refers to this mixture of hydrated oxides which was employed because of its high solubility in aqueous solutions. Typical analysis of the hydrated oxides is shown in Table I. I) HF-HC1-CYCLOHEXANONE SYSTEM Batch Separation. Effect of Acid Concentration. To determine the effect of varying the acid concentration upon the transfer of tantalum and columbium, a series of tests was made in which approximately 2.5 g of feed material was added to 25 ml solutions of 2, 4, 6, 8, and 10 N HF and 0 through 5 N HC1. Tantalum pentoxide concentration of the solu%ons was approximately 21 g per liter and columbium pentoxide was 14 g per liter. These starting solutions were shaken with equal volumes of cyclohexanone in 100 ml polyethylene bottles for 30 min. The phases were carefully separated in 125 ml glass separatory funnels. The time of contact of the solutions with the separatory funnels was kept at a minimum to reduce silica contamination. The measured phases were separated into 400 ml polyethylene beakers and the metal contents of each were precipitated by addition of an excess of ammonium hydroxide. Precipitate from each phase was filtered on ashless filter paper, ignited at 800" to 1000°C for 45 min, weighed, and analyzed by X-ray fluorescence.5 Data tabulated in Table I1 and illustrated in Fig. 1, show that maximum separation of tantalum from columbium for each HF concentration was obtained with no HCl present. The purest tantalum product was obtained with some HCl present. The highest separation factor was obtained at 2 N HF and

Jan 1, 1970

ZAY JEFFRIES, ? Cleveland, Ohio (written discussion?).-Mr. Miller&apos;s work on the path f rupture in fusion welds is fundamental. He is to be congratulated on the thoroughness with which he outlined and executed the experimental work. Following are some observations based on the data included in the papers and elsewhere. The iron nitride needles greatly increase the elastic limit of the ferrite-nitride complex. This is proved by the fact that the elastic limit of the weld material is very much higher than the elastic limit of pure

Jan 5, 1919

With a mine output as high as 5000 tpd and mill capacity of 7000 tpd, the uranium mining and milling complex owned and operated by Kerr-McGee Nuclear Corp. in the Ambrosia Lake area is the largest in the U.S. and is likely to remain so for some time. Next year, Kerr- McGee expects to have in production another mine in Section 19 of the Ambrosia area-and will begin ore production in 1976 at its new $15-million mine at Church Rock, located northeast of Gallup, N. M., where the company has already completed the shaft work and is in the early stages of project development. Ore from Church Rock will be transported to the company&apos;s facilities at Ambrosia Lake for processing. Kerr-McGee&apos;s existing eight mines in Ambrosia Lake go to depths of about 800 to 1500 ft to tap the various horizons of uranium-bearing sands in the Westwater Canyon of the Morrison formation.

Jan 8, 1974

By W. P. Blake

Forty-five years have passed since I discovered the extensive and remarkable diatom-earth beds at Monterey, California., and now I have the satisfaction of bringing to notice still another wonderful deposit in the heart of Arizona. The Monterey beds mere described at the Philadelphia Academy,* and specimens were sent to Prof. J. W. Bailey, West Point, N. Y., at that time the leading American authority upon such microscopic relics of organic life. The earth from both localities is snow-white and pulverulent. It rubs off&apos; like soft chalk upon the fingers when handled, and has the general appearance of chalk. But, unlike the Monterey beds, these newly-discovered deposits consist largely of volcanic ash, through which the siliceous shells of the diatoms are distributed. These deposits are in the central portion of the San Pedro valley,† in the southeastern corner of Pinal county. The region of their greatest development is a few miles south of the mining town of Mammoth, on the east bank of the stream, and near Redington, some 40 m. N. of Benson, on the Southern Pacific railway. The altitude is about 2600 ft. above tide. This portion of the San Pedro valley lies between the high Catalina and Rincon ranges on the west and the Galiuro mts. on the east. The Catalinas are composed chiefly of crystalline DIRECTOR OF THE ARIZONA SCHOOL OF WINES,

Jan 1, 1903

By R. M. Leibrock, J. E. Huzarevich, R. G. Hiltz

The various factors considered in recommending the initiation of a gas injection project in the southern portion of the Cedar Lake Field are discussed. Performance history under gas injection operations is reviewed and these data are analyzed, utilizing both the material balance method and the fractional flow and frontal advance expressions. Results of the analysis of the performance data indicate that the injected gas has contacted and affected at least 60 per cent of the reservoir and a substantial increase in ultimate recovery can reasonably be expected. By holding the reservoir pressure appreciably above the bubble point, the well productive capacities have been maintained substantially above the level predicted for primary operations. The analysis of the Cedar Lake project suggests that in certain limestone reservoirs, at least, the probable success of gas injection cannot be predicted simply from ohservation of permeability distribution throughout the pay section, as indicated by core analysis data, on either one or a number of wells. Further, the performance of this particular project fails to indicate any basis for classifying carbonate reservoirs in general as being inherently unsuited to a dispersed type gas injection program, thus indicating that each reservoir should be considered on its own merits, regardless of the composition of the reservoir rock. INTRODUCTION Early in the life of the Cedar Lake Field, an extensive data gathering program was initiated to provide an accurate record of reservoir performance characteristics. From the study of these data it was apparent that there was a critical need for supplementing the natural reservoir energy in order to maintain well productivities and obtain the maximum ultimate oil recovery. Accordingly, detailed engineering studies were made of the various methods of secondary recovery which might be applicable. As a result of these investigations, the decision was made to initiate a gas injection program of sufficient intensity to maintain reservoir pressure at approximately 600 psia, or some 274 lb above the bubble point pressure of 326 psia. A full scale dispersed type gas injection program has been in operation on leases of the Stanolind Oil and Gas Co. in the southern portion of the field for nearly five years, and sufficient performance data are now available to evaluate the benefits which have been derived from this project. It is the primary purpose of this paper to analyze the performance data for the Cedar Lake gas injection project and to point out the significance of the ohserved behavior with respect to certain hypotheses which have been advanced in recent years concerning the probable success of gas injection projects in limestone reservoirs. This paper properly should be regarded more on the order of a progress report, inasmuch as some revision in interpretation will undoubtedly be required from time to time as additional performance data are obtained, although the satisfactory performance of the project to date leaves little doubt as to the ultimate success of gas injection in the Cedar Lake Field. As a result of the success of the project to date, a unit was formed in the southern part of the field, effective March 1, 1951, for the purpose of continuation of the gas injection program. Participants in this unit are the Mid-Continent Petroleum Co. and Stanolind Oil and Gas Co. GEOLOGY AND STRATIGRAPHY The Cedar Lake Field is located in the northern portion of the Midland Basin area as shown in Fig. 1. The southwest portion of the field lies within a playa, or dry salt lake, which covers an area of approximately eight square miles. As might be expected, it was this lake which furnished the inspiration for the name of the field. Except for its value as a salt water disposal pit, this lake has succeeded only in magnifying the difficulties in developing this portion of the field. Typical of this section of West Texas, the area in general is relatively flat and has a semi-arid climate. The localized structure which favored the accumulation of oil is an anticline with approximately 100 ft of closure. The major axis of the structure extends in a general southeast-northwest direction. Originally this structure was defined by seismograph data, which have been subsequently confirmed by development. In general, the geologic column is typical of that found throughout the basin. From the surface to depth of approximately 1,800 ft, surface sands and undifferentiated red beds. probably Triassic. are encountered. Below this point to the producing horizon, all formations are of the Permian age.

Jan 1, 1951

By J. E. Huzarevich, R. M. Leibrock, R. G. Hiltz

The various factors considered in recommending the initiation of a gas injection project in the southern portion of the Cedar Lake Field are discussed. Performance history under gas injection operations is reviewed and these data are analyzed, utilizing both the material balance method and the fractional flow and frontal advance expressions. Results of the analysis of the performance data indicate that the injected gas has contacted and affected at least 60 per cent of the reservoir and a substantial increase in ultimate recovery can reasonably be expected. By holding the reservoir pressure appreciably above the bubble point, the well productive capacities have been maintained substantially above the level predicted for primary operations. The analysis of the Cedar Lake project suggests that in certain limestone reservoirs, at least, the probable success of gas injection cannot be predicted simply from ohservation of permeability distribution throughout the pay section, as indicated by core analysis data, on either one or a number of wells. Further, the performance of this particular project fails to indicate any basis for classifying carbonate reservoirs in general as being inherently unsuited to a dispersed type gas injection program, thus indicating that each reservoir should be considered on its own merits, regardless of the composition of the reservoir rock. INTRODUCTION Early in the life of the Cedar Lake Field, an extensive data gathering program was initiated to provide an accurate record of reservoir performance characteristics. From the study of these data it was apparent that there was a critical need for supplementing the natural reservoir energy in order to maintain well productivities and obtain the maximum ultimate oil recovery. Accordingly, detailed engineering studies were made of the various methods of secondary recovery which might be applicable. As a result of these investigations, the decision was made to initiate a gas injection program of sufficient intensity to maintain reservoir pressure at approximately 600 psia, or some 274 lb above the bubble point pressure of 326 psia. A full scale dispersed type gas injection program has been in operation on leases of the Stanolind Oil and Gas Co. in the southern portion of the field for nearly five years, and sufficient performance data are now available to evaluate the benefits which have been derived from this project. It is the primary purpose of this paper to analyze the performance data for the Cedar Lake gas injection project and to point out the significance of the ohserved behavior with respect to certain hypotheses which have been advanced in recent years concerning the probable success of gas injection projects in limestone reservoirs. This paper properly should be regarded more on the order of a progress report, inasmuch as some revision in interpretation will undoubtedly be required from time to time as additional performance data are obtained, although the satisfactory performance of the project to date leaves little doubt as to the ultimate success of gas injection in the Cedar Lake Field. As a result of the success of the project to date, a unit was formed in the southern part of the field, effective March 1, 1951, for the purpose of continuation of the gas injection program. Participants in this unit are the Mid-Continent Petroleum Co. and Stanolind Oil and Gas Co. GEOLOGY AND STRATIGRAPHY The Cedar Lake Field is located in the northern portion of the Midland Basin area as shown in Fig. 1. The southwest portion of the field lies within a playa, or dry salt lake, which covers an area of approximately eight square miles. As might be expected, it was this lake which furnished the inspiration for the name of the field. Except for its value as a salt water disposal pit, this lake has succeeded only in magnifying the difficulties in developing this portion of the field. Typical of this section of West Texas, the area in general is relatively flat and has a semi-arid climate. The localized structure which favored the accumulation of oil is an anticline with approximately 100 ft of closure. The major axis of the structure extends in a general southeast-northwest direction. Originally this structure was defined by seismograph data, which have been subsequently confirmed by development. In general, the geologic column is typical of that found throughout the basin. From the surface to depth of approximately 1,800 ft, surface sands and undifferentiated red beds. probably Triassic. are encountered. Below this point to the producing horizon, all formations are of the Permian age.

Jan 1, 1951