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The following paper, submitted by the Russian petroleum authorities, was secured through the courtesy of G. V. Ackerman, Vice President of Amtorg Trading Corporation, and N. V. Vannikoff, Representative in the U.S.A. of the United Oil and Gas Industries of the U.S.S.R. It gives an excellent view of the Russian petroleum industry as seen through Russian eyes. Noteworthy is the tremendous area over which the Russians are searching for petroleum, for this paper refers to such far-flung areas as the Arctic Tamir Peninsula, Kamchatka and Sakhalin on the Pacific, Lake Baikal in Central Siberia, the great new discovery at Neftadag in the plains of West Turkestan, and the oil of the Ferghana oasis, where the derricks look out over to the mosques of Kokand. Of interest also is the new pipe line to supply the industrial centers of Ukraine grouped around the great hydroelectric plant built at Dneprotroy on the falls of the Dnieper. The technical achievements have been noteworthy and we must pause to consider the scope of the undertakings being carried forward. Russia is at the worst a good second to the United States in petroleum reserves and for a long time to come will be a most important factor in the petroleum markets of the world. Her story should be of interest to everyone in the industry. The First Five Year Plan The first Five Year Plan, covering the period 1928-29 to 1932, accomplished the task of transforming the Union of Soviet Socialist Republics from an agricultural, backward land into a powerful independent industrial country, with an advanced technological foundation of its own for finally achieving the social reconstruction of the entire national economy. Along with the gigantic forward 'strides in industry and transportation, radical changes took place in agriculture. The creation of more than 5000 great state farms and of more than 200,000 collective farms serviced by a widespread network of machine-tractor stations has brought the U.S.S.R. to the fore as the largest agricultural country in the world. Imports of tractors and other agricultural machinery in the initial years of the Five Year Plan and the intensive output of this equipment by the great plants of the U.S.S.R. in the latter years of the plan have brought about the mechanization of agriculture in the Soviet Union. This year 250,000 tractors and 30,000 combines will operate in the fields

Jan 1, 1934

By G. F. Jenkins

The word asbestos is a broad term that has been accepted and applied to a number of fibrous mineral silicates found in nature. They are incombustible and can be separated by mechanical means into fibers of various lengths and thicknesses, but differ in chemical composition and other properties. It is generally recognized that there are six varieties of asbestos; the finely fibrous form of serpentine known as chrysotile, and five minerals of the amphibole group, i.e., amosite (not fully recognized as a mineral species name but accepted in asbestos terminology), anthophyllite, crocidolite, tremolite and actinolite. (Figs 1-4.) Physical and Other Properties The structures of asbestos fibers have been studied intensely in recent years. X-ray diffraction patterns 1 to 15 have been used as a means of identification and classification. The amphibole group structures have been fairly well established while the serpentine group has been the subject of many investigations during the past six years. Low-angle X-ray scattering techniques5 have shown that the chrysotile fibrils are "hexagonally close packed" and parallel to each other, having cross-sectional diameters varying from 180Å* units to 300Å units, while the amphibole fibers are many times larger in cross section. The electron micrographs of chrysotile asbestos (Figs 1-4) have also indicated that the fibrils might be in the form of a hollow tube. This point has been the subject of considerable controversy by a number of investigators.7 to 16 Density measurements17 made on a sample of high quality Arizona fiber did not indicate that the fiber had a hollow tube structure; however, the so-called "sheet structure" of the fibril could be distorted in such a way that it gives the appearance of a hollow tube in the electron microscope. It is of interest to quote one investigator, F. L. Pundsack,17 in this connection: Although the empirical composition of chrysotile is 3MgO.2SiO2.2H20, the true unit cell[#] composition is best represented as Mg12(OH)16Si8O20. This cell has dimensions of a= 5.3Å, b = 9.2 Å, and c = 14.6 Å where the "a" direction is the fiber axis. The calculated density of this unit is 2.56 g/cc, a value in close agreement with experimentally determined density values for chrysotile. The exact manner in which the unit cells of asbestos are stacked together to build up a single fiber of chrysotile is not known, but from various

Jan 1, 1960

By Grover J. Holt

A detailed description of the many variations in iron mining and transportation practice in Minnesota would require much space. Since a fairly detailed description of the practices then in use was published in the guidebook issued in connection with the meeting of the Institute on the iron ranges in 1920, and subsequent developments have been described by E. E. Hunner, M. H. Barber,2 and A. E. Anderson, J. M. Riddell and G. J. Holt,³ it will not be necessary here to do more than review the highlights of current practice. Details on any points of interest can be obtained through correspondence with the operators involved. † The iron ores of Minnesota, which have been formed through enrichment of the iron formation in which they occur, largely by the removal of silica, are usually covered by a blanket of glacial drift known locally as "surface." Surface material, including sand, clay, hardpan and boulders, makes up the greater portion of the stripping in open-pit operations. In some instances, stripping also includes taconite and paint rock," directly below the surface material and overlying the ore. Tacenite is the iron formation, a ferruginous chert with inter-bedded slate layers. :'paint rock" is a local term for oxidized slate layers inter- bedded in the iron formation, high in phosphorus, alumina and moisture. The iron ores fall into two classes: (I) direct shipping (merchantable ores or ores requiring no treatment except possibly crushing or screening to make an acceptable sized product), and (2) ores requiring beneficiation (such as sintering, drying, washing, jigging, high-density treatment, or magnetic separation in the case of magnetite). The Mesabi Range produces chiefly soft Bessemer and non-Bessemer ores. The Cuyuna Range produces mainly low-manganese brown ore and high-manganese black ores, with some iron ore. The Vermilion Range yields mainly Bessemer and non-Bessemer iron ore, with some hard or lump ore that finds use in the open hearth. Open-pit mining is limited to the Mesabi and Cuyuna Ranges but underground mining is done on all three. The choice of mining methods is determined by the relative economics of overburden-removal and shaft-mining costs. Stripping Practice Common practice has been to remove the bulk of the overburden during the winter season and to mine during the summer, In- the present emergency many operators are forced to forego the economies attained by year-round utilization of paper. and to equip for, and carry on, stripping and mining simultaneously. In the normal years or lean years to come, most properties probably will be overequipped and high depreciation charges Will have to be absorbed.

Jan 1, 1943

By Grover J. Holt

A detailed description of the many variations in iron mining and transportation practice in Minnesota would require much space. Since a fairly detailed description of the practices then in use was published in the guidebook issued in connection with the meeting of the Institute on the iron ranges in 1920, and subsequent developments have been described by E. E. Hunner, M. H. Barber,2 and A. E. Anderson, J. M. Riddell and G. J. Holt,³ it will not be necessary here to do more than review the highlights of current practice. Details on any points of interest can be obtained through correspondence with the operators involved. † The iron ores of Minnesota, which have been formed through enrichment of the iron formation in which they occur, largely by the removal of silica, are usually covered by a blanket of glacial drift known locally as "surface." Surface material, including sand, clay, hardpan and boulders, makes up the greater portion of the stripping in open-pit operations. In some instances, stripping also includes taconite and paint rock," directly below the surface material and overlying the ore. Tacenite is the iron formation, a ferruginous chert with inter-bedded slate layers. :'paint rock" is a local term for oxidized slate layers inter- bedded in the iron formation, high in phosphorus, alumina and moisture. The iron ores fall into two classes: (I) direct shipping (merchantable ores or ores requiring no treatment except possibly crushing or screening to make an acceptable sized product), and (2) ores requiring beneficiation (such as sintering, drying, washing, jigging, high-density treatment, or magnetic separation in the case of magnetite). The Mesabi Range produces chiefly soft Bessemer and non-Bessemer ores. The Cuyuna Range produces mainly low-manganese brown ore and high-manganese black ores, with some iron ore. The Vermilion Range yields mainly Bessemer and non-Bessemer iron ore, with some hard or lump ore that finds use in the open hearth. Open-pit mining is limited to the Mesabi and Cuyuna Ranges but underground mining is done on all three. The choice of mining methods is determined by the relative economics of overburden-removal and shaft-mining costs. Stripping Practice Common practice has been to remove the bulk of the overburden during the winter season and to mine during the summer, In- the present emergency many operators are forced to forego the economies attained by year-round utilization of paper. and to equip for, and carry on, stripping and mining simultaneously. In the normal years or lean years to come, most properties probably will be overequipped and high depreciation charges Will have to be absorbed.

Jan 1, 1943

By A. H. Daane, J. J. Hanak, F. H. Spedding

IN the study of the rare earths at the authors' laboratory, methods have been devised for preparing pure rare earths and many of their properties'- have been determined. Very little information is found in the literature on the properties of europium metal, which is the scarcest of the naturally occurring rare earths. Since we have recently prepared europium in appreciable quantities, we are in a position to describe the method of preparation and some of the properties of this metal. Metallic europium was first prepared by Klemm and Bommera who heated a mixture of potassium and EuC1, in vacuo, and obtained a mixture of europium metal and KC1. Trombe4 electrolyzed a molten salt bath containing NaC1, KC1 and EuC1, and collected the europium in a molten cadmium electrode as a cadmium alloy. The cadmium was subsequently removed by distillation but the properties of the residue indicate that pure europium was not obtained. McCoy attempted to prepare europium by distilling mercury from europium amalgam, but the stability of the Eu-Hg intermetallic compounds prevented a complete separation of the two elements. The preparation of very pure europium was suggested by previous work in this laboratory1,4 in which ytterbium and samarium were prepared by heating the respective sesquioxides with lanthanum metal turnings to 1450°C in vacuo and distilling ytterbium and samarium from the mixtures. Subsequently, small test experiments showed that europium also could be prepared by this method. A more detailed version of this method was used in the work described in this paper. Klemm and Bommer3 found by X-ray analysis that the metal had a body-centered cubic (bcc) structure with a lattice constant a, = 4.582 ± 0.00A (converted from kX units), with a bulk density of 5.30 g per cu cm. They found europium to be weakly ferromagnetic. Spedding, et al,7 found a,, to be 4.606 ± 0.001A. Barrett' showed that the bcc structure persists throughout the temperature range 5 to 3000K with a, at 5, 78, and 300°K being 4.551 ± 0.003, 4.551 ± 0.004 and 4.577 ± 0.001A, respectively. Trombe1 described europium as being iron gray, malleable, about as hard as neodymium and not attacked by cold water. He estimated the melting point to be between 1100 and 1200°C. Previous work in this laboratory indicated that the pure metal corrodes rapidly in air and reacts with cold

Jan 1, 1959

By Charles H. Jacoby

In 1774 a Swedish chemist, C. W. Schule, first recognized manganese as an element. That same year Schule's associate, J. G. Gahn, isolated the element manganese for the first time. In 1856 the Bessemer process of steelmaking gave birth to the economic importance of manganese. Later, in 1882, Robert Hadfield discovered high manganese steels. Although the primary use of manganese is in the ferroalloy industry, two additional important uses for manganese are making chemicals and dry cell batteries. Manganese is also vital to plant and animal life. Various chemical compounds of manganese are used in fertilizers, feeds, glass manufacture, paints, varnishes, and for numerous medicinal and chemical purposes. For the study of industrial minerals and rocks, only the chemical and battery grade material is of concern, but for the sake of comparison, metallurgical aspects are included in this presentation. Although currently the world's largest consumer of manganese, the United States is producing only minor amounts of ore at the present time. This is due primarily to the fact that although huge deposits of manganese occur within our borders, all are of such low grade as to be economically unfeasible to mine. For many years various government agencies and segments of private industry have devoted sizable sums of money and time in an attempt to upgrade ores from the various deposits, and also in an attempt to recover manganese from blast furnace slags. In view of current world prices, and the quantity of high grade material available, there is little likelihood that any of these approaches will be found to be economically feasible in the near future. Geology and Mineralogy Mineralogy There are over one hundred minerals that contain manganese. These minerals vary from those with compositions that are predominantly manganese to those having only minor percentages. [ ] Geology From a geological standpoint most manga¬nese deposits are complex. In general, it can be said that all primary deposits of manganese are carbonates or silicates. The most productive and profitable have been those of sedimentary origin and residual concentrations. Examples of these residual types of deposits are associated with the metamorphosed lodes of Madhya, Pradesh, India, and the lateritic deposits of Orissa and Bihar, India; nodules in the residual clays of the Philippine Islands, U.S. southern Appalachians and Arkansas, Ghana, and Brazil. Sedimentary manganese deposits are best exemplified by the Nikopol district of Russia and the Tchiatouri area of Georgia, USSR. Hydrothermal replacements are characterized by the rhodochrosite deposits of Butte and Phillipsburg, Mont. In general, the hydrothermal type deposit has not resulted in any large tonnages being produced, but may have given

Jan 1, 1975

By E. C. Truesdale, R. K. Waring

THE Research Division of The New Jersey Zinc Company (of Pa.) has conducted, over a period of years, numerous tests of the reducibility of various zinc ores and the reactivity of various kinds of coal, using a number of different experimental methods. Most of these tests have involved the reduction of mixtures of ore and coal. In such cases the following simultaneous reactions are believed to be mainly responsible for the production of zinc, as was shown by Bodenstein1 some years ago: ZnO + CO = Zn + CO2[I] C + CO2 = 2CO[2]. Each of these reactions is dependent upon the other for the supply of CO and C02, respectively, and the over-all rate of formation of zinc vapor will be determined by the slower of these two reactions. An analogous pair of reactions sometimes of importance is: ZnO + H2 = Zn + H2O[3] C+ H2O=CO+H2[4] While it is possible to obtain an indication of the relative reducibility of various ores, or of a fine versus a coarse ore, by testing them with a given coal, and while coal reactivities may be measured in a corresponding manner, a more direct determination of relative reaction rates is possible by carrying out the desired reactions, such as I and 2, separately and under reproducible conditions. It is one purpose of this paper to present some of the results that have been obtained by the latter method. C. G. Maier2 discusses the relative rates of reactions I and 2 and concludes that while at relatively low temperatures reaction I is faster than reaction 2, this difference becomes less with increasing temperatures, although at smelting temperatures reaction I is still the faster. He also says (p. 48), "At temperatures . . . between 1100° and 1300°C the zinc oxide reduction reaction is intrinsically more rapid than its physical limitations; that is, it is limited by gas diffusion rates." In the course of numerous reactivity tests involving the separate use of reactions and I and 2, we have obtained data that show by direct experiment, we believe for the first time, the correctness of Maier's statements concerning these reactions. We also include data on the relative rate of reaction 3, involving reduction by hydrogen. Finally, some interesting results obtained by carrying out the reduction of a zinc ore-coal briquet in streaming atmospheres of nitrogen, carbon monoxide and hydrogen, respectively, are presented.*

Jan 1, 1941

By F. D. Rosi, F. C. Perkins, L. L. Seigle

An investigation was made of the mechanism of plastic flow in coarse grained specimens of both sponge and iodide titanium at low (-196°C) and high (500° and 800°C) temperatures. Deformation by slip occurs predominantly on a {1011} plane and in a <1120> direction over this entire temperature range, and secondary slip on {101-1} planes becomes more prevalent with overthisentireincreasing temperature.range, The crystallographic habit of the predominant twin planes becomes more prevalent with type is temperature-dependent, and deformation by twinning increases as the temperature of testing is lowered. Kink bands were not observed at -196OC and rarely at the high temperatures. A LTHOUGH the deform a tional mechanisms in . -titanium at atmospheric temperature have been extensively investigated," there is little information regarding the influence of testing temperature on these mechanisms. The only available data come from the recent work by McHargue and Hammond, who extended single crystals of iodide titanium at a temperature of 815°C. No significant changes in the types of slip and twinning planes were observed, but increased activity on the type I, order 1 pyramidal slip planes and on the type 11, order 2 twinning planes was reported. These planes contribute very little to the deformation process at room temperature.&apos;&apos; &apos; Since there is interest in titanium as a material for use at both low and high temperatures, the present investigation was undertaken to examine the slip and twinning behavior in coarse grained specimens of titanium at -—196", 500°, and 800°C in order to determine the general effect of temperature on the mechanism of plastic deformation. Experimental Material Used and Specimen Preparation—Both sponge and iodide titanium were used in the present investigation; chemical analyses appear in Table I. These materials were arc-melted under argon into 25 g slugs, which were then cold-rolled approximately 90 pct to a sheet thickness of 0.05 in. Since the strain-anneal technique was used for obtaining coarse grains, the cold-rolled sheets were made into tensile specimens which were then annealed to produce a relatively coarse uniform grain structure prior to critical straining. The details of the strain-anneal treatment. size of grains, and the method for preparing the specimen surface for optical microscopy have been described in a previous report.&apos; In order to obtain a wider spread in crystal orientation for the present work, it was necessary to vary the rolling schedule to reduce the degree of preferred orientation in the annealed sheets prior to critical straining. Methods for Tensile Testing—The apparatus for experiments at the temperature of liquid nitrogen (—196°C) consisted of two concentric stainless steel

Jan 1, 1957

By J. Larsen-Badse

The resistance to dry sliding abrasion us been measured for some hardened and tempered carbon steels. The wear resistance, defined as the reciprocal of the volume loss per unit sliding distance, is found to vary linearly with the hardness of the abraded surface. The data fit two lines, one, of high slope, for the pure metals and for the annealed steels and another, of smaller slope, for the hardened and tempered carbon steels. A relationship is developed showing the alwasion resistance to be proportional to the hardness of the material and to en, where n is the exponent of work hardening. The values of n and of the hardness FOR most materials a high resistance to abrasion is generally associated with a high value of indentation hardness. Brine11 even used the abrasion resistance as a measure of hardness in an attempt at expanding the hardness range covered by his indentation-hardness test.&apos; When comparing different types of materials there is, however, only a very general relation between abrasion resistance and hardness. Sample brittleness seems to contribute to the deviation from a direct relationship. In general, increased brittle- are those relating to the heavily deformed abraded surface. However, for materials having n constant or varying m a regular manner over a wide range of strailts, the wear resistance will also be a linear function of the bulk hardness of the material. For tempered steels containing a dispersion of cementite in ferrite the increase in wear resistance due to the dispersion is found to be a linear function of the volume fraction of Fe3C and of the reciprocal of the mean free ferrite path. This indicates indirectly that the yielding of this material, when it is already heavily deformed, follows the Orowan criterion. ness leads to decreased abrasion resistance.&apos; When comparing materials in the same group, e.g., the metals, the spread is less. Kruschov found that the abrasion resistance of pure metals and of annealed steels is directly proportional to the hardness of the metal. For hardened and tempered steels he obtained another linear relationship, one of smaller slope and intersecting the line for the pure metals at the location of the data for the annealed steels. He also found that the abrasion resistance of cold-worked metals is independent of the degree of cold working. This shows, as he concluded, that the process of abrasion work hardens the metal in the surface region to a very high degree.

Jan 1, 1967

INTRODUCTION This chapter summarizes porphyry copper deposits within the State of Alaska. Prospecting for porphyry copper-type deposits in Alaska germinated during the 1940&apos;s, grew slowly during the &apos;50&apos;s, boomed during the &apos;60&apos;s, and matured in the &apos;70&apos;s. Although large expenditures have been made in the search for porphyry-type deposits, most accrued data lies dormant in company files. However, an adequate base exists in the literature for a general synthesis of areas that contain porphyry prospects. To simplify the summary, porphyry molybdenum deposits as defined by Clark (1972) are omitted. Description of deposits in their geologic setting permits some correlations between deposit characteristics and crustal environment. These correlations allow speculation about the genesis of the deposits. The summary also attempts to group deposits on the basis of general mineralogic characteristics because diorite model deposits are separated from quartz phenocryst-bearing hosts. Data presented in this chapter summarize observations by the author, published descriptions of specific areas and deposits as noted in the bibliography, and comments by various government geologists. E. M. MacKevett, Jr., D. H. Richter, and H. C. Berg of the US Geological Survey have been particularly helpful. Because few comprehensive descriptions of individual porphyry copper deposits exist for this area, much of the data presented is new to the literature. Details of structure, isotopic geochemistry, and petro- genesis for individual deposits are largely lacking and even the general geology of some belts is not well understood. Details on petrography of Alaskan porphyry copper occurrences are inadequate for construction of ternary diagrams (e.g., Figs. 36a, b, pp. 103, 104, for the northern Cordilleran orogen). Petrographic descriptions summarized in the text are largely from published descriptions whose sources are cited. Porphyry copper-type deposits in Alaska include deposits with pervasive pyrite that contain disseminated copper (but not necessarily coproduct molybdenum). Available data preclude differentiating the deposits by size. No Alaskan porphyry copper deposit is now in production but this is believed to be, in part, a function of economics. In some cases available geologic information is in- adequate for classifying deposits. Some de- posits included with porphyry copper may, with further exploration, be demonstrated to be some other genetic type. Alaska has three distinct porphyry copper provinces: the Hogatza plutonic belt, the Continental Margin belt, and the Interior belt. Each belt contains deposits with characteristic geologic features distinct from those of other belts. Fig. 24 shows the continental margin belt to extend inland from

Jan 1, 1978

By W. C. Hagel

Previous inuestigators have repovted unusually low H* and Do values for self-dzf@szon in certazn bcc metals, e.g., chromium nnd y -uvanium. It has been postulated that this is nn experimental crl -tetion for the existpnce of a four -atom ring meclzanzsm, mid there could be. zmpovtant theoretrcal Implicatlons. By utilizing a precise sectioning technique with Cr51 as the tracer, self-dzffi-lsion measurements in large grains of 99.99-pct Cr were extended from 1200° fo 1600"C. A least- squares analysis of the data yields that D 0.280 exp (-73,20U/RT) cm2 sec-&apos;. These AH* and Do unlues are not anomalous; there is little reason to believe that n vacancy mechanism is not opevatiue. Apparent differences at lower temperatures may result from preferential diffusion along short-circuititing paths and/or sample contamination. WITH continued technological effort, chromium and chromium-base alloys should ultimately become useful high-temperature structural materials. Accurate measurements of self-diffusion coefficients in the pure metal are necessary for a quantitative understanding of sintering, grain growth, creep, and other related rate processes. However, two conflicting determinations have been reported.* Using an Since careful diffusion studies normally yield Do values ranging from 0.1 to 10 cm2 sec-l, the Paxton-Gondolf results require independent experimental corroboration before an undue amount of speculation arises to explain the apparent anomaly. As discussed by Nowick6 and clearly shown by Hoffman and Turn-bull7 for self-diffusion in silver, a low AH* and Do can arise from preferential diffusion along grain boundaries or other short-circuiting paths. The most reliable data come from high-temperature measurements where volume effects predominate. Following a precise sectioning technique developed for determining silver diffusion in the intermetallic compound AgMg8 and cation diffusion in the corundum oxide Cr2O3,9 the purpose of this study was to measure true volume diffusion in high-purity, large-grain samples at higher temperatures than considered previously. Another point of interest is the frequent proposal10-12 that chromium undergoes an allotropic transformation between 1375" and 1800°C where the diffusion data might then show a discontinuity. I EXPERIMENTAL 1) Sample Preparation. The highest purity (99.997 pet) Cr currently available is produced by reduction of chromium tri-iodide. Three pounds of the resulting crystal bar were shipped in a sealed container with a complete chemical analysis from the vendor.* In conformity with the procedure used for

Jan 1, 1962

By Elmars Ence, Harold Margolin

The partial isothermal section of the Ti-Cu-Zr system at 750°C has been studied. The crystal structure of Ti2Cu has been detevnlined as tetragonal and when expressed as face-centered tetragonal, a = 4.164, c = 3.611 A, and c/a = 0.867. TITANIUM systems in which ß-titanium decomposes eutectoidally into a and a compound rather readily are known as active eutectoid systems. Recently in active eutectoid alloys based on the Ti-Cu system, and containing additionally A1 and Zr, it has been found that zirconium may produce both moderate weakening and marked strengthening at elevated temperatures.&apos; In order to obtain some insight into the behavior of zirconium, an attempt was made to determine whether compounds of the type Tix Zr and TixZryCu exist. Only results of the Ti-Zr-Cu studies are reported here since data on Ti-Zr alloys will be presented in a separate publication. EXPERIMENTAL PROCEDURE Alloys were nonconsumably arc melted in argon atmosphere as 15-g buttons, prepared from materials of the following purities: Bureau of Mines electrolytic Ti — Bhn 63 OFHC copper Reactor Grade Zirconium Bhn .C 150 Prior to alloy preparation the electrolytic titanium was premelted to avoid excessive spattering of the charges during melting. The weight losses during melting did not exceed 1 pct of the total weight of the charge. The alloys prepared are listed in Table I together with analyzed compositions. in cases where they were determined. Specimens for heat treatment were wrapped in molybdenum sheet, annealed in argon-filled quartz capsules, and quenched by breaking the capsules under iced brine. About 1 to 2 sec are required to remove the capsule from the furnace, drop it into the iced brine and break it. Because of the insulation effect of the quartz, this delay in quenching should not produce a large drop in temperature. In many instances, no difference or little difference has been detected between the same specimen quartz capsule quenched or directly quenched in vacuum by an impinging stream of water.&apos; Ti-Cu-Zr alloys were homogenized for 48 hr at 825°C prior to annealing at 750°C. Annealing for 5 days at 750°C produced the same results as 11 days at temperature and it was therefore assumed that 5 days was sufficient to establish equilibrium. Titanium-copper alloys were homogenized for 40 hr at 900°C prior to heat treatment for 6 days at 750°C. Specimens for metallographic examination were electropolished and etched with the following solution:

Jan 1, 1962

All the TECHNICAL PUBLICATIONS and CONTRIBUTIONS published in 1941 are available at Institute headquarters, unless otherwise noted They are also on file in many public, university and technical libraries and, when so indicated in the list, may be found in the TRANSACTIONS TECHNICAL PUBLICATIONS in Classes A-Metal Mining, 13-Milling and Concentration, H-Industrial Minerals, and I-Mining Geology are distributed in MINING TECHNOLOGY, which is issued every other month Technical Publications in Classes C-Iron and Steel Division, D-Nonferrous Metallurgy and E-Institute of Metals Division are distributed in METALS TECHNOLOGY, which is issued twice quarterly TECHNICAL PUBLICATIONS in Class G-Petroleum Division are distributed in PETROLEUM TECHNOLOGY, which is issued every other month TECHNICAL PUBLICATIONS in Classes F-Coal Division, J-Mineral Industry Education Division, K-Mining Administration, and L-Geophysics, are issued as separate pamphlets An Institute member is entitled to one copy of any printed TECHNICAL PUBLICATION or CONTRIBUTION Copies of TECHNICAL PUBLICATIONS listed have been mailed to members of the Institute according to their registration by classes CONTRIBUTIONS and other TECHNICAL PUBLICATIONS will be sent upon request A member may purchase an additional copy of a TECHNICAL PUBLICATION or a CONTRIBUTION at one cent a page, minimum charge, 25¢ Nonmembers may purchase any CONTRIBUTION or a TECHNICAL PUBLICATION of the F, J, K, or L classes at the same rate, but the nonmember price per copy for METALS TECHNOLOGY, MINING TECHNOLOGY or PETROLEUM TECHNOLOGY is $1 25 domestic, $1 35 foreign countries. TECHNICAL PUBLICATIONS (separate pamphlet form), $2 per annum domestic, $2 50 foreign. METALS TECHNOLOGY, $7 per annum domestic, $7 80 foreign (Iron and Steel Division and Institute of Metals Division ferrous and nonferrous papers) MINING TECHNOLOGY, $6 per annum domestic, $6 60 foreign (metal mining, milling and concentration, Industrial Minerals Division, and mining geology papers) PETROLEUM TECHNOLOGY, $6 per annum domestic, $6 60 foreign Bound volumes have been mailed to members that have requested them, and MINING and METALLURGY Is mailed each month A member is entitled to one volume a year on his membership and he may purchase for $2 50 one copy of a volume not already received, additional copies of the same volume, $5 Nonmembers in the United States may purchase the volumes listed at $5 each, outside of the United States and its possessions, $5 6o Extra single copies of MINING AND METALLURGY, 25¢ current issue, back numbers 500 each to members, to nonmembers 50¢ current issue and $1 each, back issues Subscription price to nonmembers and to members for extra copies, $3 per annum domestic, $4 00 foreign.

Jan 1, 1941

By William Lodding

Muscovite was the crystalline material used in the experiments discussed in this paper. It was both wet and dry ground for various periods of time. The effects (physical and chemical changes) produced in grinding are analyzed by use of thermal analysis. That grinding may change a crystalline material both in a physical and in a chemical sense has been shown by a number of authors in recent years. Mackenziel and Bartha2 reported the effects of careful grinding on muscovite, quartz, gypsum, dolomite, etc. Increase in specific surface produced by grinding implies increase in total energy of a system. Newly produced surfaces are chemically more reactive; dislocations may be introduced during grinding and, on the other hand, existing strain may be released by the same process, as shown by Holt, et a1.3 All these changes are easily detected by thermal analysis, but it is not easy to separate the multiplicity of effects registered and to arrive at quantitative interpretations. This paper is an attempt to analyze, by the use of thermal analysis, some effects produced in grinding. In differential thermal analysis (DTA) one measures the sum of all thermal changes occurring in a substance during heating or cooling; e.g., chemical changes, such as decompositions, synthesis, oxidation, reduction, etc., and physical changes such as phase transformations, changes in specific surface and thermal conductivity, strain release, etc. By thermogravimetric analysis (TGA), on the other hand, only chemical changes involving weight loss or gain are recorded. Similarly, gas evolution analysis (GEA) will register only reactions involving gas evolution. By performing two or all three of these methods of thermal analysis simultaneously and on the same specimen, one can separate the different effects registered and, by difference, evaluate their magnitude. The results of TGA are usually plotted as percent weight against furnace temp. When one differentiates weight against furnace temp, a rate of weight-change curve is obtained, and the resulting differential thermogravimetric (DTG) plots are similar in appearance to DTA thermograms for the same reaction. While the integrated area under a DTA peak represents enthalpy and can be expressed in calories per gram the area under the corresponding DTG peak represents the weight change which took place during a reaction. The similarity of DTA and DTG thermograms obtained from one material can be seen in Figs. 1 and 2. EXPERIMENTAL A Fisher mortar grinder and a porcelain mill with burundum balls were used for both dry and wet grinding. Muscovite was first carefully hand-filed and screened on 20 and 100 mesh. The middle fraction was considered essentially unaltered muscovite.

Jan 1, 1968

By Dan Crackel, G. G. Ramos, Mark Heisel

INTRODUCTION Feasibility studies indicated that a cratering type stoping method was best suited to the character of the first ore block at Carr Fork. This method known as vertical crater retreat (VCR) has since been modified to a combination cratering and deck blasting using VCR drop raises for initial undercut development . The modified form retains many of the advantages of VCR while allowing high tonnage production blasts which have offset many of the disadvantages. FIRST CONCEPTS AND PREMISES Geologic Considerations The Steep Highland Boy (SHB) skarn orebody, the first of several blocks being developed, is a steeply dipping 70° to 90° limb of a syncline, with a width averaging 25 m (82 ft). The bed has a consistent east-west strike length of over 400 m (1300 ft) and extends from the surface to depths of over 1000 m (3300 ft). The footwall is highly fractured quartzite and the hanging wall grades from garneti te to limes tone and hornfe 1s. Because of the limestone in the hanging wall, the hanging wall appears more competent than the footwall. The ore is garnetite with lenses of massive sulphide and magnetite. The quartzite footwall is highly fractured not only because of the bedding but also due to the folding and intrusion of the quartz monzonite. This irregular footwall outline of some stopes in- creases the likelihood of excessive dilution. The principal ore mineral is chalcopyrite with some bornite. The garnetite ore is quite variable in terms of compressive strength and drillability. In addition to the sulphide and magnetite lenses, it is transected by clay- altered dikes and major and minor north-east faults. TABLE (1) gives the range and mean strengths of the rocks. Investigating Mining Methods Initial consideration of a suitable mining method centered around maximum safety and efficiency with minimum potential dilution. The following major methods were considered and investigated. Cut and fill mining was eliminated because of low productivity, the cost and problems associated with providing fill, and the relatively unsafe nature of the method. Sublevel caving was rejected due to the unpredictable cavability of the waste and the geometry of the ore body. Conventional sublevel or blasthole methods require excessive development, as fan and ring drills are limited to efficient drilling in the 18 to 25 m range (60 to 80 ft). Mining downdip with equipment drilling small diameter holes would have required eight separate extraction/drill horizons with crosscuts and associated excavation in the main ore block. The use of down the hole (DTH) machines cap- able of drilling 165 m (6g in) diameter holes

Jan 1, 1981

By J. N. Hobstetter, J. J. Becker

Deformed copper single crystals exhibited, upon annealing, a recrystallized twinned grain with a twin plane parallel to an active deformation plane, rotated approximately 22" about its pole, or else did not recrystallize at all. If extraneous deformation was not carefully removed, no simple orientation relationship was found. RECRYSTALLIZATION textures have been a subject of practical interest for many years, but any real understanding of their formation will have to start with a study of the recrystallization of carefully deformed single crystals. Some efforts have been made in this direction,&apos;-&apos; but much more experimental information is needed before a satisfactory picture of the crystallography of recrystallization can be formed. This paper reports a few results in copper single crystals. The crystals studied in this investigation were grown by the Bridgman method," and their orientations determined by the back-reflection Laue technique." Some specimens were simply deformed in compression, others were sheared, and still others tested in a rotating-grip device, in attempts to remove end constraints. The details of their deformation behavior are described elsewhere.&apos; The deformed specimens were annealed and the orientations of the recrystallized grains were determined optically, as described by Barrett and Levenson.8 Compressed Specimens Specimen 17-A, whose orientation is given in Fig. 1, was compressed to a total of 19 pct. As observed before,&apos; increasing deformation took place by increasing density of slip lines in initially formed clusters, with little if any formation of new slip clusters in unslipped areas. The specimen was then etched in nitric acid until its length had been reduced from 0.766 to 0.735 in. It was annealed at 1000°C, in increments of a few minutes. After 63 min, two small grains had appeared in the center, Fig. 2. They were found to be twinned with respect to each other (AB, Fig. 4). After 30 min more, the specimen was completely recrystallized. A typical view of it is given in Fig. 3. A summary of all orientations found is given in Fig. 4, in which the prominent grain G is in (001) standard projection, and the poles of the active slip planes after deformation are indicated by SP (primary slip plane), CrSP (cross-slip plane), and CnSP (conjugate slip plane). All the orientations found were related through seven orders of twinning. A "family tree" of these twins is given in Fig. 5. Furthermore, the BG twin composition plane lies close to the cross-slip plane

Jan 1, 1954

By R. M. Brick

SEGREGATION can occur only in cast alloys that solidify over a range of temperatures with a difference in composition of liquid and solid phases within this range (ignoring monotectic systems and chemical reactions as in rimming. steels). Thus a pure binary eutectic alloy should show no segregation unless undercooling occurs for one of the solid constituents of the eutectic; e.g., chill-cast Al-12 per cent Si alloys. The phasial condition implicitly described above-solidification over a range of temperatures with a compositional difference between solid. and liquid-is found in nearly all solid solutions or combinations of solid solutions and eutectics. Metastable conditions of solidification of these types of alloys cause coring; i.e., a difference in composition between the center of a dendrite and its periphery. This composition gradient can be detected usually only by microscopic examination of etched structures; it is a "micro" effect. The gradient of more immediate industrial concern is that between the center of a cast section and the surface layers. This gross (macro) effect is usually determinable only by sampling of the casting at different points, with chemical analyses of each sample. If the compositional difference is of the same type as in coring, the first parts to freeze being enriched in higher-melting-point constituents, and vice versa, the effect is called normal segregation. When what is apparently the first part of the casting to solidify shows a higher concentration of low-melting-point constituents, the effect is called inverse segregation. These macro effects are quite separate from the micro effect, coring, yet the latter must be. described first because it is an essential part of the picture. CORING Solid Solution, Ni-Cu The nickel-copper phase diagram is reproduced in Fig. Ia, in which the solid lines represent the equilibrium liquidus 1, 3, 7 and solidus 2, 5, 8, and where the vertical 1, 4, 8 represents a 55 per cent Cu alloy. Upon moderately rapid solidification, the first dendritic axes of composition 2 (see Fig. 1b) start to form at a temperature somewhat under I. Solidification continues by growth of the dendritic nuclei, but at temperature 4 the increment solidifying is of composition 5. The rapidity of this crystal growth prevents diffusion of nickel and copper atoms from adjusting the composition of the entire dendrite at 5, which it would be under equilibrium conditions. The average composition of a specific dendrite, or the entire solid phase, at temperature 4 might be that indicated

Jan 1, 1944

By G. R. Frank, R. E. Willett, E. H. Hollingsworth

The most generally accepted equilibrium diagram for A1-Fe alloys has a eutectic system on the aluminum side with an essentially insoluble constituent of the formula, FeAl,, as the second phase. In 1938, Bradley and Taylor1 did report a phase change of FeAl,, but this change has never been confirmed. According to them, FeA1, is the stable phase only at higher temperatures; at lower temperatures, it is converted into Fe2Al7 and aluminum. It has now been found that there is, in fact, a phase change of the Al-Fe constituent on the aluminum side of the equilibrium diagram. This change, however, is not the one reported by Bradley and Taylor. The alloys used were cast by continuous processes and had these analyses: Fe - 1.98 to 2.02 pct, Cu-0.01 pct, Si - 0.01 pct, Mn - 0.01 pct, Mg - 0.00 pct, Zn - 0.00 to 0.01 pct, Cr - 0.00 pet, Ti - 0.00 to 0.04 pct. The constituent in these alloys was identified by X-ray analysis with a Guinier camera and by chemical and X-ray powder diffraction analyses. Two procedures were used to separate constituent for the last two analyses. In one procedure, it was separated by treating a sample with a solution of methanol saturated with iodine. And in the other procedure, it was separated by first applying, at 12 amp per sq ft in 15 pct sulfuric acid at 70°F, an oxide coating to a sample, and then dissolving this coating in a solution of 35 ml of 85 pct H3PO4 and 20 g of CrO3 per liter. Several observations directed attention to a phase change of the A1-Fe constituent. Differences that appeared too great to be accounted for by micro-structure alone were found in the voltages required to apply the same thickness of an oxide coating to products from rapidly and slowly chilled ingot. Even more striking was the difference in appearance of the coatings themselves. One applied to a product from a rapidly chilled ingot was dark gray in appearance, in fact, almost black, while one applied to a product from a slowly chilled ingot was essentially white. Also, even a short period of thermal treatment at an elevated temperature of products from rapidly chilled ingot led to the same anodizing behavior as that of products from slowly chilled in-

Jan 1, 1962

By G. J. Wilson

Review of difficulties experienced in drilling directional wells in the offshore Grand Isle Block 43 field showed most failures of drill pipe, drill collars and casing to have been associated with excessive dog-legs. Alleviation of difficulties was approached by synthesizing theoretical and practical concepts in a planned dog-leg control program. Preventive measures necessary to control dog-leg severity and corrective measures used to reduce unacceptable doglegs are discussed. When other measures fail, deliberative measures as outlined can be employed after the probable cumulative fatigue damage to be sustained by the drill pipe has been determined. Results of a program successful in virtually eliminating problems stemming from excessive dog-legs indicate that control of dog-leg severity in directional wells is feasible and will cause no decrease in the over-all drilling rate. INTRODUCTION Prompted by an increasing frequency of drill pipe, drill collar and casing failures, a study of 50 directional wells representing 592,000 ft of hole, including 444,000 ft of deviated hole, drilled in the offshore Grand Isle Block 43 field was conducted in early 1965. A number of drill pipe washouts and six keyseating problems were recorded and a detailed review was made of 16 failures which had required fishing effort in 10 of the 50 directional wells drilled prior to June, 1965. These problem wells are exemplified by Wells G and F for which pertinent data are shown in Figs. 1 and 2. Data pertaining to all of the 16 failures are summarized in Table 1. Inspection of these data shows most of the problems to have been associated with dog-legs in excess of theoretical limits suggested by Lubinski&apos; and excessive dog-legging is indicated to have been concomitant with whipstocking in several of the problem wells. Results of the investigation agreed with those reported by Schenck2 who had concluded that problems could be expected when dog-leg severity exceeded limits proposed by Lubinski. Since Schenck had demonstrated the desirability and feasibility of drilling directional wells without excessive dog-legging, a dog-leg control program was established in June, 1965 for wells drilled in the Grand Isle Block 43 field. This paper reviews the methods by which theoretical and practical concepts were synthesized to develop a program of preventive, corrective and deliberative measures which virtually eliminated problems stemming from excessive dog-legs in directional wells. Dog-legs of a magnitude causing no damage are referred to as permissible +1CONTINENTAL OIL CO. HARVEY, LA.

By Grover J. Holt

A DETAILED description of the many variations in iron mining and transportation practice in Minnesota would require much space. Since a fairly detailed description of the practices then in use was published in the guidebook issued in connection with the meeting of the Institute on the iron ranges in 1920, and subsequent developments have been described by E. E Hunner,1 M. H Barber,2 and A. E. Anderson, J. M. Riddell and G. J. Holt,3 it will not be necessary here to do more than review the highlights of current practice Details on any points of interest can be obtained through correspondence with the operators involved.† The iron ores of Minnesota, which have been formed through enrichment, of the iron formation in which they occur, largely by the removal of silica, are usually covered by a blanket of glacial drift known locally as "surface." Surface material, including sand, clay, hardpan and boulders, makes up the greater portion of the stripping in open-pit operations. In some instances, stripping also includes taconite and "paint rock," directly below the surface material and overlying the ore. Taconite is the iron formation, a ferruginous chert with interbedded slate layers. "Paint rock" is a local term for oxidized slate layers interbedded in the iron formation, high iii phosphorus, alumina and moisture The iron ores fall into two classes- (I) direct shipping (merchantable ores or ores requiring no treatment except possibly crushing or screening to make an acceptable sized product), and (2) ores requiring beneficiation (such as sintering, drying, washing, jigging, high-density treatment, or magnetic separation in the case of magnetite) The Mesabi Range produces chiefly soft Bessemer and non-Bessemer ores. The Cuyuna Range produces mainly low-manganese brown ore and high+manganese black ores, with some iron ore. The Vermilion Range yields mainly Bessemer and non-Bessemer iron ore, with some hard or lump ore that finds use in the open hearth. Open-pit mining is limited to the Mesabi and Cuyuna Ranges but underground mining is done on all three. The choice of mining methods is determined by the relative economics of overburden-removal and shaft-mining costs. STRIPPING PRACTICE Common practice has been to remove the bulk of the overburden during the winter season and to mine during the summer. In the present emergency many operators are forced to forego the economies attained by year-round utilization of equipment and to equip for, and carry on, stripping and mining simultaneously. In the normal years or lean years to come, most properties probably will be overequipped and high depreciation charges will have to be absorbed

Jan 1, 1942