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By C. H. Noren

For some years the Du Pont Company has utilized computer calculations to study the various theoretical properties of explosives. These studies have yielded valuable information on the effects of density changes or formulation changes on detonation rate, detonation pressure, explosion pressure, heat of explosion and numerous other properties, and have aided in evaluating the theoretical potential of explosives. In addition, a multitude of laboratory tests have been utilized for the evaluation of explosives. When comparing the computer data and the voluminous test data it became evident that numerous anomalies existed. Tests in rock were required to study explosives under borehole confinement. This fact was further emphasized after numerous field measurements showed that the borehole velocity of commercial explosives did not match the theoretical value but was dependent on conditions of field use. Since we are interested in the practical aspects of blasting, a program was initiated to evaluate explosives as used in commercial blasting. INSTRUMENTATION Most of you are familiar with the extensive work that has been done by the U. S. Bureau of Mines in their studies of strain measurements in rock. Early in our work we adopted procedures similar to those used by the Bureau of Mines. Strain pulses were measured by gages cemented in boreholes. Since we were primarily interested in the effect of explosives in the zone where fracture might occur, this system offered several disadvantages for Du Pont: 1. Cemented gages were expensive and not reusable. 2. When gage holes were used for several shots, there was considerable question as to the condition of the rock after the first shot.

Jan 1, 1968

By Nicholas J. Grant, Robert F. Wilde

TAYLOR and Floyd's"" work in establishing phase diagrams based on the elements Ni-Cr-Ti-A1 has led to an understanding of the precipitation hardening mechanism in alloys based on these elements. Nordheim and Grant4 concluded that in simple alloys, and where the aluminum to titanium atomic ratio was such that less than three out of five aluminum atoms were replaced by titanium, the precipitate on aging is the face-centered-cubic Ni 3A 1 phase, called They further found that increasing amounts of hexagonal ? phase, Ni3Ti, precipitated from these alloys when the titanium content exceeded the solid solubility of both matrix and Ni3A1. For alloys of Ni-Cr-Ti-Al, in which the titanium and aluminum contents each ranged from 0 to 4 wt pct, the titanium-rich was superior for strengthening to either pure ?' or 7. It was also noted that the combined titanium plus aluminum content (atomic pct) was a direct measure of the high temperature strength and overaging temperatures for these alloys.4 The present investigation was undertaken to extend existing data on precipitation hardening in the more complex commercial alloys containing higher titanium plus aluminum, and with significant quantities of cobalt, molybdenum, and carbon. Experimental Procedure Reforging of As-Received Bar Stock—The alloys were received as ground, forged bar stock. Chemical analyses and the as-received bar diameters are shown in Table I along with the ASTM grain size after the various treatments. All stock except the Waspaloy was reforged to % in. diam to gain material and to facilitate machining of stress-rupture specimens. Forging was carried out at 2100°F, and discontinued when the bar temperature fell to 1800°F. Heat Treatments—For experixental simplicity it was desirable to heat treat all of the alloys at, the

Jan 1, 1958

PRESIDENT WILLIAM L. SAUNDERS,1 NEW YORK, N. Y. PAST PRESIDENTS CHARLES F. RAND,1 NEW YORK, N. Y. BENJAMIN B. THAYER,3 NEW YORK, N. Y. FIRST VICE-PRESIDENT PHILIP N. MOORE,1 ST. Louis, Mo. TREASURER GEORGE C. STONE,1 NEW YORK, N. Y. SECRETARY EMERITUS ROSSITER W. RAYMOND NEW YORK, N. Y. SECRETARY BRADLEY STOUGHTON NEW YORK, N. Y.

Jan 8, 1915

By Gregory M. Dexter

Recent litigation in Pennsylvania between three coal-mining companies and a private water company resulted in the payment by the coal companies of the equivalent of about $500,000 to buy a new water supply to replace that which had been damaged by acid drainage from strip mining. An investigation of the relevant facts indicates that the water could have been treated by spending about $40,000 on equipment and $15,000 yearly for chemicals, labor, and power until the contarnination could be reduced about 80 pct. The water company's supply, furthermore, had deteriorated largely by reason of dry weather before stripping was begun by the coal companies. Payment to the water company should not have exceeded $300,000 and could have been as low as $100,000. Strip mining of coal is common in Pennsylvania. The most important objection to it in Pennsylvania is generally acid pollution of runoff water. An outline of the methods, therefore, that could be used to reduce such pollution, to compare acid-contaminated waters. and to treat such waters to make them satisfactory for public and industrial use is worth-while. The watershed of the West Penn Water Co. covers about 4.5 square miles, 20 miles west of Pittsburgh, and has two 90,000,000 gal reservoirs supplying about 1,300,000 gal daily for public and industrial use of which 450,000 gal daily are for two railroads. The pollution arises from weathered derivatives of typical'" Coal Measures"' rocks, the principal source being pyrite (and marcasite) in Pittsburgh and Rooster coals. Springs and seeps on hillsides issue from sandstone and limestone formations intersecting shale or clay land surfaces, or from perched water tables. The two reservoirs create an artificial permanent water table. Soap-hardness tests on three seepage samples taken in a dry summer ranged from 150 to 500 ppm. Water sampled came from aquifers above Pittsburgh and Rooster coals, obviating the possibility of contact with pyrite-containing coal. Since acid contamination of mine waters is the result of chemical reactions of oxygen and water with pyrite, it will be reduced by the exclusion of either air or water. The Sunnyhill Coal Co. has applied this principle in its "contouring" method of strip mining by burying contaminated coal-waste material under a compact, smoothed-up surface of top-soil, gravel, clay, and sand at a cost

Jan 1, 1950

By Robert Baschwitz, John Chipman

The distribution of silicon between liquid silver and Fe-Si-C alloys has been studied at 1420oand 1530°C. The data are consistent with earlier studies. New data of Hager on the liquidus lines of the system Ag-Si and the distribution data are used to obtain the activity coefficient of silicon in both liquid phases. Data on the heat of mixing in iron permit accurate extension to 1600°C. Equilibrium data involving SiO2 and silicon in liquid iron together with revised data on the free energy of SiO2 are used to fix the activity of silicon in the infinitely dilute solution. The binary system exhibits strong negative deviation from ideality. At infinite dilution ? Si at 1600" is 1.25 x 10'3, and at concentrations up to NSi = 0.4 the slope d InySi/dNSi has a constant value of r; = 13. It is found that logysi in the ternary solutzon is approximately but not exactly the same function of Nsi + NC as of NSi in the binary. The results are consistent with currently available data on the free energy of Sic and its solubility in molten iron. LIQUID solutions of the system Fe-Si-C have acquired considerable importance as the laboratory prototypes of blast furnace hot metal. Equilibrium studies involving such solutions and slags approximating those of the blast furnace have yielded useful information concerning the thermodynamic properties of blast furnace slags. In studies of this kind great importance attaches to a knowledge of the thermodynamic activity of silicon in the solution as a function of temperature and composition. An attempt was made by Chipman, Fulton, Gokcen, and askey' to evaluate all of the pertinent data on this system and to deduce the desired relation between activity, composition, and temperature. These authors published data on the solubility of graphite and Sic in molten Fe-C-Si solutions and on the distribution of silicon between liquid iron and liquid silver. They showed further how the activity of silicon in very dilute solutions in liquid iron could be calculated from equilibrium data involving the molten alloy and solid SiO,. These calculations rested on the published thermodynamic properties of SiO, in- cluding its heat of formation which at that time was recorded as -209.8 kcal. This value has been under suspicion for some time and has recently been replaced by the concordant results from two independent laboratories2,3 which place the heat of formation of a-quartz at -217.6 kcal. This revision necessitates a re-evaluation not only of the activity of SiO2 in slag but also of silicon in molten iron. It is the purpose of this paper, therefore, to recalculate the activity of silicon, and in furtherance of this objective to present new data on its distribution between liquid Fe-Si-C alloys and liquid silver. HEAT OF SOLUTION OF SILICON IN IRON In order to determine the effect of temperature upon the activity coefficient it is necessary to know the heat of solution of silicon in iron as a function of composition. This is found in the data of Korber and Oelsen4 shown in Fig. 1. The curve corresponds to the following equation, which is of a form suggested by Wagner:5 Here AH is the heat absorbed in kilocalories in forming one gram atom of molten alloy from its molten elements and the N's are atom fractions. The relative partial molal enthalpies of the components, each referred to its pureliquid state and defined as zFe = aFe - PFe and zsi = HSi — -psi, are shown graphically. At low concentrations zSi = -28.5 kcal, in agreement with Kijrber and Oelsen's computation. This is in good agreement with the value of -29.3 kcal obtained by Chipman and Grant6 using an entirely different method. ACTIVITY AT INFINITE DILUTION From the known free energy of SiO, it is possible to obtain the activity of silicon in dilute solution in liquid iron from equilibrium studies. The heat of formation of a-quartz is —217.6 kcal and the heat capacity and entropy data are given by Kelley and ~ing.' The free energy of formation of ß-cristo-balite at temperatures above the melting point of silicon is expressed by the following equation: Si(Z) + O2(g) = SiO2 (crist); AF" =-226,500 + 47.50T [I] The value of the deoxidation product for silicon [%Si] x [%O]2 at 1600°C according to Gokcen and chipmans is 2.8 x 10"5, in agreement with results of Hilty and Crafts.9 More recent works of Matoba,

Jan 1, 1963

By Sam N. Dewitt, Albert S. Trube

This paper presents a discussion of the pressure maintenance operations which were begun in the New Hope Field. Franklin County. Texas. in 1944. The project has required the injection of extraneous waters at depths from 7.300 to 8.000 ft with intake well-head pressures up to 4.000 psi in three different reservoirs — the Bacon. Hill. and Pittsburg. Records of oil and water production. water injection and the GOR have been kept for each reservoir and reservoir pressures were taken at regular intervals. These data indicate that the Bacon Reservoir had no apparent water encroachment up to the time of water injection. However. the Pittsburg and Hill reservoirs had some natural water influx hut not sufficient to prevent pressures from declining below the bubble point. The Bacon and Hill reservoirs responded almost immediately to water injection. while the Pittsburg which is the least permeable. has shown good pressure response only since .August, 1948. The principle objective of the project has been to increase ultimate recovery. Success of the project to date also has resulted in reduced lifting costs. Esti- mates based on the initial water breakthrough patterns indicate that the primary objective of substantial additional recovery will he accomplished, and there is a possibility that the original estimates elf oil recovery with pres-sure maintenance will he exceeded. INTRODUCTION This pressure maintenance project was one of the earliest primary pressure maintenance programs to he attempted on a multiple zone field. There are three producing reservoirs into which water is being injected for the purpose of maintaining pressure and increasing the ultimate recovery- from each. This paper is limited in scope to al1 account of the development of the project. the pressure production relationship prior to the injection of water and the effect of water injection on the producing reservoirs. Also discussed are the nature of the injection system and the indicated results on initial water break-through in the Bacon Reservoir. FIELD CONDITIONS The New Hope Field, which is located about 12 miles northeast of Winusboro, Franklin County, Texas, is an elongated symmetrical anticline containing four known oil reservoirs. The reservoirs are of the Trinity group of the Comanchean or Lower Cretaceous period and are found in Table I. The oil productive portion of each reservoir is not present in all of the producing wells because their areas and positions vary with respect to one another. Fig. 1 shows the relative position of the four reservoirs and illusIrate? how some wells could penetrate all four, while others are restricted to three. two. or perhaps one. depending on structural location. The first three reservoirs contain undersaturated oil. The deepest. the Elledge, has a primary gas cap. Although this reservoir covers a considerable area of the field. it has a very thin section and a low order of permeability. Elledge producing wells have generally been characterized by an early increase in GOR, making it necessary to recomplete them in other reservoirs. (At present. one well is completed in the Elledge. which is still producing.) Because of the difficulties en-countered in producing oil from this reservoir. and the small quantity of oil actually present. future attempts at producing it will probably be on a salvage basis during the later life of the program. For this reason, the remainder of this report will be confined to a discussion of the Bacon, Hill and pius-burg reservoirs.

Jan 1, 1950

By D. W. Fuerstenau

THE object of this article is to point out the experimental relationship which exists among contact angle, adsorption density, zeta potential, and flotation rate data. In each of the experiments discussed in this article, the surface properties of quartz, as a function of pH, were measured in solutions to which constant quantities of dodecylammonium acetate were added. Morrow1 and deBruyn2 worked with solutions containing 4.08x10-5 moles per liter, whereas Fuerstenau3 and Seele worked with solutions containing exactly 4x10 moles per liter, but this difference is not significant. The pH of the solutions was regulated with HCI or NaOH in all cases. In each case, the addition of collector was constant, but the concentration of dodecylammonium ions decreased because of the formation of dodecylamine at higher pH values2 Contact Angles: Gaudin and Morrow1 presented data for the contact angle of quartz in solutions containing 4.08x10-5 moles of dodecylammonium acetate per liter between pH 2 and pH 10.15. Using the same captive bubble techniques, the writer measured contact angles on quartz in solutions containing 4x10-5 moles of dodecylammonium acetate per liter at pH values ranging from 9.9 to 13.2. Both sets of data are presented in Fig. 1, in which the contact angle in degrees is plotted as a function of the pH of the solution. From pH 2 to about 8, the contact angle increases slightly with increased pH, but further increase in pH causes a sharp rise in the contact angle to a maximum of about 80º. At pH values above 11.6, the contact angle drops sharply, reaching zero by pH 12.6.

Jan 12, 1957

By Frank C. Greene

The principal event in the development of oil and gas in Missouri in 1942 was the drilling of the Cities Service Oil Company's No. I Jim Cook, in the northwest corner, NW. 1/4 sec. 32, T. 65 N., R. 39 W., Atchison County, in the northwest corner of Missouri. This well, not yet completed, bailed several barrels of free oil in about 27° Baume from a sand called the Bartlesville by those in charge, at a depth of 1450 ft. The well is on a block of leases obtained after the area, which is covered by several hundred feet of glacial drift, had been prospected by core drilling. Earlier in the year the same company drilled a well on the Glen Gray farm in the southwest corner, SW. 1/4 sec. 29, T. 65 N., R. 39 w., to a depth of 2427 ft. in the Hunton lime with a rotary drill. Oil stains in this hole led to the drilling of the second well. Table i .—-Wells Drilled for Oil and Gas in Missouri in 1942 Country Number of Number of County Oil Wells Gas Wells Dry Andrew.......... Atchison.......... I Bates............ 2 6 Caldwell.......... I 3 Cass............. I Clinton........... I Holt............. I Jackson.......... I I Knox............ I Nodaway......... I Platte............ 4 4 Ray.............. 5 Sullivan.......... I Totals.......... I 7 28 Otherwise drilling in Missouri was uneventful, with a total of only 36 Completions, of which one was a very small oil well, Seven were small gas wells and 28 were dry holes. The total footage drilled was 24,7541/2 ft., of which 14,0281/2 was by cable tools and 10,726 ft. by rotary. Twelve of the dry holes were drilled into Mississip-pian or older beds. Table I gives a summary of activities by counties.

Jan 1, 1943

By Frank C. Greene

The principal event in the development of oil and gas in Missouri in 1942 was the drilling of the Cities Service Oil Company's No. I Jim Cook, in the northwest corner, NW. 1/4 sec. 32, T. 65 N., R. 39 W., Atchison County, in the northwest corner of Missouri. This well, not yet completed, bailed several barrels of free oil in about 27° Baume from a sand called the Bartlesville by those in charge, at a depth of 1450 ft. The well is on a block of leases obtained after the area, which is covered by several hundred feet of glacial drift, had been prospected by core drilling. Earlier in the year the same company drilled a well on the Glen Gray farm in the southwest corner, SW. 1/4 sec. 29, T. 65 N., R. 39 w., to a depth of 2427 ft. in the Hunton lime with a rotary drill. Oil stains in this hole led to the drilling of the second well. Table i .—-Wells Drilled for Oil and Gas in Missouri in 1942 Country Number of Number of County Oil Wells Gas Wells Dry Andrew.......... Atchison.......... I Bates............ 2 6 Caldwell.......... I 3 Cass............. I Clinton........... I Holt............. I Jackson.......... I I Knox............ I Nodaway......... I Platte............ 4 4 Ray.............. 5 Sullivan.......... I Totals.......... I 7 28 Otherwise drilling in Missouri was uneventful, with a total of only 36 Completions, of which one was a very small oil well, Seven were small gas wells and 28 were dry holes. The total footage drilled was 24,7541/2 ft., of which 14,0281/2 was by cable tools and 10,726 ft. by rotary. Twelve of the dry holes were drilled into Mississip-pian or older beds. Table I gives a summary of activities by counties.

Jan 1, 1943

FIRE tubes are commonly made in order to frighten horses or to harm enemy soldiers, but although fire issues from them, they do not cause much damage because they cannot be used at a distance. If you wish to use them, you are not able to approach close to the enemy, for if there is anyone who is afraid, he does not let you approach nor does he come near you until he sees that they have finished burning. Thus, in short, the assault with this is one that is seen beforehand, and for which there is always time to decide on some action in defense. It is indeed true that they are beautiful things to see and when the name tubes of fire is heard it terrifies those who do not have a defense ready. When four, six, or indeed ten or twelve of these are put in the hands of as many courageous and united men, they are surely good in forcing passage on a guarded bridge, or in entering or holding a gate, road, or other narrow place. They serve also for setting fire to dwellings or the enemy's supplies,

Jan 1, 1942

By John L. Lamont, Walter Crafts

SELECTION of an alloy steel for a heat-treated article has been facilitated by methods for the calculation of hardenability,1 as-quenched hardness,2,3 and tempered tensile strength.4 Ductility and toughness may also be estimated if the steel is completely hardened on quenching,5,6 and the present study was carried out in order to develop a basis for estimating the Izod impact strength of partially hardened steel. The investigation was directed toward the prediction of Izod impact strength in steels of normal commercial quality without consideration of special compositions or heat-treatments that might produce abnormal brittleness. It was found that Izod impact strength of alloy steel is controlled by hardness, degree of hardening on quenching, and grain size. In fine-grained steels the impact strength for any given degree of hardening is inversely proportional to the tempered Rockwell C hardness, and the relation of impact strength to hardness is lowered by incomplete hardening. Calculation of the tensile strength and impact strength of heat-treating steels has shown that, except at very high strengths, tensile strength is raised by alloys without loss of impact strength whereas the tensile strength gained by higher carbon contents tends to be accompanied by a disproportionate loss of toughness. Plain carbon steels give relatively low and unpredictable impact strength. The calculation is sufficiently accurate to be helpful in the selection of alloy steel, and common grades of alloy steel have been evaluated with respect to combinations of tensile strength and impact strength attainable after heat-treatment in sections from I to 4 in. in diameter. PROCEDURE The study of the relation of hardness to impact strength was based on test data derived from 24 heats from four producers. The steels included the following SAE and AISI compositions: 1020, 1o30, 1040, 1340, 3310, 3316, 4320, 4330, 4340, 8620, 8630, 8640, 8720, 8730, 8740, 9310, 9317, 9440, 9917 and three high-alloy chromium-nickel-molybdenum steels. As far as is known, the steels tested were of normal commercial quality. They were supplied in 4-in. sections, which were forged to smaller sizes, prenormalized, and machined to final dimensions. Heat-treatment was carried out by heating to the usual austenitizing temperature for the grade of steel, holding for one hour per inch of thickness and quenching in still oil at room temperature. Previous work had indicated that this quenching treatment approximates a severity of H = 0.35. The bars were tempered as follows: ½ in., I in., and I 5/8 in., 2 hr; 2 ½ in., 3 hr; 4 in., 5 hr. All bars were air-cooled from the tempering tem-

Jan 1, 1947

By J. N. Butler, R. J. Morris

A series of organic collectors has been developed which successfully float synthetic secondary uranium minerals, such as autunite, carnotite, and torbernite. Recoveries up to 97 pct have been obtained. With cleaning of rougher concentrates, ratios of concentration as high as 15:1 are possible on head assays of 0.10 to 0.50 pct U 3 O 8. Additions of certain base metal salts aid in recovery and materially increase the rate of flotation and selectivity of the collectors for the synthetic minerals. Flotation tests on natural uranium minerals have not yet equaled results obtained on the synthetics, although these collectors do give better results than conventional collectors for nonsulfide minerals. RAPID increase in mining and milling uranium ores during the past seven years and the discovery of large tonnages of uranium-bearing material too low in grade to stand the cost of leaching have developed considerable interest in possible methods for beneficiating these marginal ores. Such ores are generally classed as those containing less than 0.10 pct U3O8. Development of a beneficiation method that would give both high recovery and high ratio of concentration would also make possible the beneficiation of higher grade ores and would provide higher grades of feed to existing leaching plants. Although considerable research and testing on physical or physico-chemical beneficiation of domestic uranium ores has been done in the past, to the best knowledge of the authors only a single application of physical beneficiation is now in operation on a commercial scale. Flotation has been attempted on the basis of mineral association rather than by direct concentration of the contained uranium minerals. Flotation studies conducted on this project on certain ores gave recoveries of 60 to 70 pct of the uranium by the use of conventional flotation agents such as oleic acid, but ratios of concentration were in the order of 1.5:1 to 2.5:1. Subsequent cleaning to upgrade the concentrates rapidly increased losses in the cleaner tailings, which were not later refloated in the rougher flotation. Selection of Collector: In selecting desirable organic collectors for these oxide systems, a thorough study was made of the relationship between structural characteristics and collector activity by an examination of the behavior of a number of different functional arrangements present in a variety of organic molecules, (see Fig. 1). It is generally accepted that a collector must have a relatively long-chain hydrocarbon radical and a chemically reactive elec-trophilic center. Such a requirement could be met by a large number of compounds, but steric effects at the uranium mineral surface, solubility, compat-ability with aqueous systems, air avidity, bond strength at the mineral surface, interfacial concentration of the collector, and diffusion rate of the formed complex from the air-water interface eliminated many as unsuitable for this purpose. Preliminary investigations were completed of possible collector designs consisting of aliphatic and aromatic hydrocarbon radicals attached to stable combinations of nitrogen, oxygen, sulfur, and halogen electrophilic centers, Fig. 1.Tests were made to determine melting point spans, solubility of mineral-collector combinations in various solvents, reactions with soluble uranium salts, contact angles, and floatability by semi-quantitative beaker methods.' Contact angle determinations were not too useful because of the fine particle sizes of available mineral samples. From the foregoing study it appeared that nitrogen-sulfur electrophilic centers coupled with straight-chain saturated alkyl hydrocarbon radicals would hold the most promise for floating secondary uranium minerals. As the dithiocarbamate compounds can be made to combine these attributes they were selected for further study. The dithiocarbamates form a parallel structure to the xanthates, with the fortuitous exchange of

Jan 1, 1957

By P. W. Andrews, R. B. Toombs

ECONOMIC STRUCTURE OF MODERN INDUSTRIAL ECONOMIES The role of minerals in modern industrial economies may be examined in several ways. There are relationships with the various sectors of the economy: the primary, secondary, and tertiary industrial groupings and activities. Mineral supply and demand activities can be measured in terms of national accounts criteria. The economic policy objectives of the modem industrial economy are based to a considerable extent on the needs of the nation for economic supplies of miner- al materials. There is an important role for minerals relative to national security in peace and in wartime and many national policies are directed toward ensuring adequate sup- plies of minerals. Environmental control in the modem industrial economy is increasingly concerned with matters related directly to the production and use of minerals and these matters, in turn, bear importantly on conservation in mineral supply and demand. Mineral polices include specific provision for research and development activities concerned with the production and the use of minerals. In all, national policy objectives will be shaped in considerable part by the circum- stances of mineral supply and demand: the relative degree of availability from domestic and foreign sources, the state of the mineral-processing industries, and the degree of development of the mineral-using industries, and per capita and total changes in requirements. Goods made from mineral raw materials are the basis of all advanced societies and although this is taken for granted, every country is continually dealing with problems of mineral supply and demand. Considering that in the first 50 years of this century the consumption of mineral materials in a highly Industrialized country such as the United States increased by six times while the population was doubling, it becomes apparent that if a country is to enjoy rapid economic growth it must have access to huge and ever-growing supplies of mineral materials at lowest possible cost. Adequate supplies of mineral materials and wise usage of mineral resources have always been among the most important determents of a nation's survival The importance of access to adequate mineral supplies is increasing every year and this has significant international, as well as national, implications because of the unique locational characteristics of mineral resources. It is generally acknowledged that no particular type of natural resource is essential to a high level of national income or to economic progress. A country's endowment of natural resources need not exercise a determining influence on the course of its national income over time, provided it is able to trade. What is required for economic progress is the availability of a substantial quanti-

Jan 1, 1976

By S. Nenno, T. Saburi, Y. Mizutani, M. Yomarnoto, K. Komatsu

In the equilibrium phase diagram of the Ni-Mo sys-tem1,2 available at present, intermetallic compounds (or ordered phases)ß(Ni4Mo) and ?(Ni3Mo) are known to exist to the nickel rich side. In our recent investigations on Ni-Mo alloys, however, it has been found that the quenched alloys from the high temperature region containing more molybdenum than the Ni4Mo do not decompose directly into 0 and when annealed isothermally below the peritectoid temperature, i.e., 865°C. This note is to report the existence of Pt2Mo type superlattice (possibly ordered Ni2Mo) as a metastable phase in the early stage of decomposition. Alloys containing 20.1, 22.7, and 24.4 at. pct Mo were prepared by vacuum-melting electrolytic nickel of 99.9 pct purity and molybdenum powder of 99.9 pct purity in an alumina crucible. From the resulting ingots, sheets 0.3 mm thick were obtained by forging, hot-, and cold-rolling. The sheet specimens were water-quenched from ! region and subsequently annealed for various periods of time at temperatures below the peritectoid temperature. On these specimens were made optical-microscopic and transmis-sion-electron-microscopic observations. Fig. 1- Optical micrograph of the 22.7 at. pct Mo specimen annealed for 100 hr at 700°C after quenching. (ß + ?) region, B, nucleated along a grain boundaries are invading the preexisting (ß + Ni2Mo) region, A. Details of A are observable only by electron microscopy. Etchant: 60 pct HNO3-40 pct CH3COOH.

Jan 1, 1970

By J. M. Roberts, D. M. Barnett

The activation energy required to break a pinned dislocation line away from its condensed atmosphere of impurity atoms is calculated as a .function of applied stress, without neglecting line tension. Reasows are presented for not assuming the effect of line tension to be negligible when considering the problem of freeing a small segment of dislocation from an impurity atmosphere. The dislocation is considered to he pinned at each atomic size along its length and the pinning points are assumzed immobile. The development is a refinement of the origznal cottrell-bilby1 theory. The solution is compared to recent approximations developed by cottrell3 and Haasen5 in which line tension con- IN 1949 Cottrell and bilby1 considered the problem of determining the force required to pull a dislocation away from its condensed atmosphere of impurity atoms. They also examined the effect of thermal fluctuations on this force. The dislocation line was pictured as bowing out in a triangular loop under the action of an applied stress, and the activation energy necessary to free the dislocation from its atmosphere was calculated as a function of stress, line energy, and dislocation-solute atom interaction. siderations were neglected. A qualitative explanation of the yielding process in terms of the activation of Frank-Read sources is presented, but the lack of a realistic solution to the dynamic dislocation problem involved prevents an extension of the model at present. A self-consistent correlation between the present calculations and experimental data for delay time associated with yielding and the temperature dependence of the upper yield stress was made. Favorable agreement was noted. It is concluded that extension of the original Cottrell-~ilby' theory which includes line tension effects can just as well describe the yielding process as other approximations3,5 which neglect line tension. Cottrell and Bilby found the form of the activation energy vs stress curves to be almost independent of the line energy and the interaction energy (i.e., these parameters only affected the activation energy U by a scale factor). A check of the theory was accomplished by comparison with the experimental data of McAdam and Mebs2 for the lower yield stress as a function of temperature. cottrell,3 in 1957, attempted to obtain a simple closed-form solution for the activation energy as a function of stress by linearizing the quartic equation relating displacement of the dislocation line and applied stress. It was argued that since the contribution to the line energy/atomic plane of a dislocation is made by the long-range stress field of the dislocation through a term of the type (Gb3/2p)ln A/ro, where

Jan 1, 1963

IN CHAPTER I it was shown that the approximate market value of the copper produced at the twelve big Porphyry mines from 1905 to 1931, inclusive, was $2,821,300,000. This represented the refined metal ready for shipment to the consumer. In addition, at least $50,000,000 worth of gold and silver had been produced, more than $30,000,000 coming from the Utah mine alone. Consequently, the revenues totaled about $2,871,300,000, as shown in Table 58. Society paid this sum for a given quantity of metal that it wanted for industrial use. Where did the money go? Who were the direct beneficiaries of the creation of this new wealth? These questions this chapter will answer in a general way. Because some necessary data are not available, an exact tabulation in detail can not be made, but Table 58 is believed to reflect with reasonable accuracy the disposition made of the aggregate income from the twelve operations. The word "operations" is used advisedly because the complexity of corporate relations precludes the possibility of picking out companies, as could be done if each enterprise were an independent entity such as Miami, for example. Some explanation of the table and some elaboration of the items under "Outgo" is desirable. In the first place, it is assumed that the sum of surplus current assets existing in various treasuries at the end of 1931 was substantially equivalent to the “new” money that actually was put into the enterprises as a group. Less than $20,000,000 in new capital was realized from securities sold by the Utah Copper Co., the remaining funds coming from earnings. In respect to some of the others, such as Chuquicamata, Inspiration, and Andes, the amount of new money was much greater. However, of the two items-total new capital invested and total current surpluses-the former

Jan 1, 1933

By R. B. Lincoln

THE function of a pyrometer protecting tube is to maintain an atmosphere about the thermocouple most favorable to its continued accuracy and long life, and at the same time permit the weld of the couple to attain the full temperature of the area or object being measured. In addition to protecting the thermocouple from the chemical or alloying effects of the products of combustion or bath being measured, the tube must also protect the couple from mechanical injury. The conditions met in practice vary so much that no one material is suitable for all applications. The usefulness as well as the expense of maintenance of a pyrometer system are influenced greatly by a choice of the most suitable protecting tube. The tube must protect the couple without itself becoming too great an expense item. The protecting tube should have the following qualities: (1) A melting point well above the highest temperature to be encountered. (2) Sufficient strength through the entire range of temperatures to hold up its own weight and resist such shock and jar as are unavoidable. (3) It must be impervious to the atmosphere or bath to which it will be subject. (4) It must not give off any vapor injurious to the couple. (5) It must not form any oxides fusible below the highest temperature to be measured. The proper location of the tube in the furnace is almost as important as the choice of material. The tube must be placed as near to the work to be heated .as possible. It must be kept out of the direct path of flame, both because that would give too high temperature readings and because partly burned fuel will destroy the tube faster than the quiet products of combustion.

Jan 9, 1919

By Charles Catlett

Having had charge during the past year of the operations of the New River Coke Company, the second largest, if not the largest, coke-producer in this district, my attention was called particularly to the yield of coke from the coal as coked in a bank of beehive ovens, as the record showed that this yield, while believed to be well up with the practice of the district, was much lower than the analysis of the coal indicated it should be. The coal is well known to many members of the Institute, and the scope of this paper does not include a discussion of its occurrence and development. It suffices to say that the New River district comprises the mines working on the coals of No. XII. or the Conglomerate Series of the Rogers brothers, which are located on New river and its tributaries, and which find an outlet for their product east and west over the Chesapeake and Ohio Railway. The New river through this section carries the drainage from an extensive peneplain in which it has formed a very striking and stupendous canon, probably the most striking east of the Mississippi river. The only practical access to this territory is by means of this canon and the Chesapeake and Ohio road, and the opportunities for development by other lines may be considered as nil. If it were not for the fact that this road, farther west, reaches and develops entirely different coals, which are found in other measures, the New River district might properly be spoken of (as is now done at times) as the " C and 0. field." For fuller information on the geology of the region, those interested are referred to the ery complete monograph on the subject by Mendenhall and Campbell of the United States Geological Survey. The rocks are the same as those which carry the more widely

Jan 1, 1900

By R. S. Bradley

WHAT are known as insulating firebrick are lightweight firebrick with low thermal conductivity designed primarily for use in direct contact with furnace gases. These are a recent development in the refractories industry, and are really an outgrowth of the type of insulating brick suitable for use behind refractory walls developed by the insulation manufacturers. To differentiate between these two types of brick, the manufacturers have recently agreed upon the use of the term "Insulating Firebrick" to apply to the type of brick suited for use in direct contact with furnace gases, and the term "Insulating Brick" for the type suitable for use behind refractory walls. Insulation was applied to steam pipes as far back as 1900. This was a low-temperature insulation, the most common type being magnesia blocks. The next development was applying insulation to the outside of furnace walls, a service which necessitated an insulating material of higher temperature resistance. Natural diatomaceous earth, both in the powdered and brick form, was used; this was efficient and is still used extensively for backing up refractory walls where the inner surface temperature of the insulation does not exceed 1600° F.

Jan 1, 1937

By James A. Barr

Phosphate rock is a natural rock containing one or more phosphate minerals usually calcium phosphate, of sufficient purity and quantity to permit its use, either directly or after beneficiation in the manufacture of commercial products.1 The principal minerals in phosphate rock have the apatite structure which may be represented by the type formula: Ca10(X2) (PO4)6 where X represents the hydroxyl group (OH), chlorine or fluorine, either singly or collectively. The calcium may be partly replaced by sodium, magnesium, and other positive ions such as manganese, strontium, lead, uranium, cerium, yttrium and other rare earths. The PO4 radical may be partly replaced by small quantities of UO4, AsO4, SiO4, CO3, SO4, or Vo4. A typical commercial rock is usually a calcium phosphate containing 3 to 4 pct fluorine, the major impurities being limonite or other iron oxides, clay, aluminum phosphates and silica as quartz sand. A little vanadium is present in most of the domestic rock deposits (except the Tennessee Brown Rock), according to Jacob, Hill, Marshall and Reynolds! A little uranium occurs in the Florida leached zone, as will be brought out later. The chemical analyses are reported as P205, or tricalcium phosphate Ca3(PO4)2, the latter often designated by the trade name BPL (bone phosphate of lime). Commercial analyses usually report iron and alumina as oxides, lime as CaO and silica or insoluble. Colony3 examined many samples of apatite, staffelite, dahlite and American phosphorites and concluded that all have identical X-ray diffraction patterns. The phosphates in the phosphate rock have very minute crystalline structures. The mineral apatite Ca3(F.Cl) (PO4) 3 is the principal primary source of the element phosphorus, and occurs widely distributed in igneous rocks but rarely in a minable mass. Only about 12 pct of the world production of phosphate rock comes from primary apatites; the remainder is derived from secondary phosphorites. These phosphorites have been formed by the alteration of sediments by solutions containing phosphoric acid. Such solutions have come from the weathering or leaching of igneous rock containing apatite, bone deposits of prehistoric animals, marine life or guano deposits. These phosphorites are mostly alterations of phosphatic limestones. The sedimentary phosphate deposits are of marine origin and may have been enriched by subsequent solution of the more soluble calcium carbonate by waters containing carbon dioxide, by physical concentration by wave action, and by redeposition of the dissolved phosphate ions. Uses of Phosphate Phosphorus is the spark of life and is the structure builder and one of the main elements of plant food (fertilizer). Without phosphorus, life cannot exist. A "complete" plant food[t] in addition to phosphorus compounds contains potash, which acts as a catalyst to convert nutrients to useful forms, nitrogen to supply the growth element and many minor elements. The cycle of supply of phosphorus is from the apatite to solution and soil, absorption of plant life, decay and return to the soil or by animal life feeding on the plants. With insufficient supply of phosphorus in vegetation, life is not prolific. If crops are removed from

Jan 1, 1960