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By J. R. Long, E. L. Anderson, R. S. Dean, F. S. Wartman

Titanium has been estimated to comprise about 0.65 per cent of the earth's crust and ranks fourth in abundance among the metallic elements suitable for engineering uses. In spite of this, applications of titanium for structural purposes have not as yet been developed. Its commercial exploitation has been largely confined to the chemical industries and the production of paints and pigments; no doubt because of the difficulties that lie in the way of preparing the pure ductile metal. Published reports, however, indicate that ductile titanium can be prepared and possesses some unique properties. This, together with the occurrence in this country of several important titaniferous deposits, has led the Bureau of Mines to investigate processes for the production of metallic titanium, methods required for its fabrication, and the properties that may be produced in this interesting metal. Methods of Preparing Metallic Titanium Many early investigators claimed to have isolated metallic titanium; but in the light of present knowledge, it seems that they really had produced various mixtures of carbides and nitrides that have a metallic appearance but are brittle, hard, and unworkable. The first metallic titanium pure enough to be malleable when cold was produced by Hunter1 in the early part of the twentieth century. Kroll,~ van Arkel,~ and Fast,4 subsequently confirmed the facts that pure titanium is a. ductile metal and that small amounts of impurities were responsible for previous reports of brittleness. When heated, titanium reacts chemically with various gases, such as hydrogen, oxygen and nitrogen; if the volume of gas thus absorbed is too great, the metal becomes brittle and unworkable. The principal difficulty in making ductile titanium is prevention of such contamination, and the success of a given process may be judged by the completeness with which it solves this difficulty in a practical manner. Of the gases mentioned, hydrogen is the least objectionable, since its absorption by the metal is completely reversible and, although dimensional changes occur and absorption of hydrogen embrittles the metal, the gas may be removed readily by heating in a high vacuum for a short time. On the other hand, the absorption of oxygen or nitrogen results in the formation of permanent solid solutions of the oxide and nitride, which cannot be decomposed by the strongest reducing agentsz with sufticient completeness to restore the inherent ductility of the metal. Because of

Jan 1, 1946

By W. H. Emmons

The exploration of deposits of the metals will never become an exact science. There will always be an element of uncertainty in prospecting and developing mines. In countries where the surface has been closely scrutinized, most of the deposits whose outcrops contain valuable metals have probably been discovered. Many metalliferous deposits, however, are normally so much altered at the surface that the true significance of their outcrops is likely to be obscured. If a deposit is not exposed, its presence may become known by some one of its characteristics that is different in kind or in degree from a similar feature of the associated rock. Thus, a deposit that is not exposed may be discovered because of its magnetic property. So few minerals are strongly magnetic that the value of magnetic surveys is limited, but the dip needle has nevertheless proved of great aid in locating magnetic belts, and these in some regions are associated with workable iron ores. The Cuyuna Iron Range of Minnesota, which does not exhibit any outcrop of iron ore, was discovered by drilling "areas of attraction" that are due to belts of magnetic rocks associated with the iron ores. In some regions the use of the dip needle is justified, even if it does no more than reveal the strike of the rocks, since a knowledge of the latter enables the driller to locate and point his holes to advantage. The measures of gravity by the use of the pendulum are so accurate, or the limit of error is so small, that one might detect the presence of a concealed tabular deposit approximately at the surface, 34 ft. (10.36 m.) thick, having a density double that of the surrounding rocks. However, not many deposits have a density twice that of ordinary rocks and a thickness as great as 34 ft.; if they lie a short distance below the surface the density or the thickness must be even greater. Consequently, there is not much hope of sufficiently developing the gravity method of detecting deposits of heavy ores to make it of practical value. If the limit of error could be reduced to about one-tenth the present factor, and if the rather tedious and painstaking methods of determining gravity that are now in use could be simplified, the method would promise some degree

Jan 1, 1918

By P. Nicholls

Patent records show that the attempt to improve the burning of fuel by mixture or pretreatment with chemicals dates back to the early years of the last century. By 1845 English and French patents had included the specific beneficiations of elimination or reduction of smoke, soot and clinker; reduction of the ashes; elimination of sulphur fumes; increase of the rate of burning; increase of the time a given charge of fuel would last; and, in most patents, a saving of fuel. The earlier patents specified additions up to 80 lb. or more per ton of fuel, but after 1860 the quantity was seldom more than 4 lb. There is no record of the extent to which these patents were commercialized, but after 1874 many American patents were assigned to companies specializing in treatment of coal, so it is probable that the products were marketed on a considerable scale at least as early as that date. From 1900 on, many proprietary products were marketed under the general name of "fuel savers," the principal sales being in small packages for the use of householders; savings of from 10 to 40 per cent of the coal were promised. Starting with 1927, the use of proprietary or other mixtures of chemicals was extended to power plants and to treatment of coals at the mines, the claims of saving of fuel being subordinated to those of general improvement and, in particular, to reduction of clinker-ing. Such expectations are attractive and a number of companies experimented with or adopted the practice. There were reports of improved operation, but, apparently, few were confident enough that these improvements were due to the salts to publish the results of tests or their records of operation. There are no data on the yearly tonnage of coal treated but indirect reports suggest that it has been relatively large. Since its establishment in 1910, the U. S. Bureau of Mines has continually received inquiries about these products. At the request of other governmental departments it made tests in 1910, 1916 and 1930, using certain proprietary products applied according to the instructions of the vendors; these tests were made with eastern coals in domestic and

Jan 1, 1938

By L. H. Levenson, Charles S. Barrett

Numerous determinations1-' of the texture of cold-rolled polycrystalline iron, steel, and ferritic alloys have been made with good agreement among the various observers as to the principal features of the texture common to all, but there has been no adequate explanation of the texture in terms of, the behavior of individual grains. This study presents an explanation of the texture based on the observed rotation of single crystals when deformed in a manner similar to a grain in the aggregate, a method we have found useful in leading to a better understanding of compression and tension textures;8,9,10 in particular, the aim has been to determine experimentally the end orientations of rolled single crystals of iron. These are discussed in connection with the point of view of Weverl and of Boas and Schmid2 that the rolling texture is a simple compression texture (compression normal to the rolling plane) superimposed on a simple tension texture (tension in the rolling direction), and the point of view of Kurdjumow and Sachs3 that three ideal end orientations exist. Experimental Method The single crystals used were in the form of disks cut from a stock of crystalst pre- pared in this laboratory by a strain-anneal method from mild steel decarburized and purified in hydrogen, the details of which have been described elsewhere.11 To ensure maximum elongation in the rolling direction and to simulate approximately the rolling of a grain in an aggregate, lateral flow was constrained by placing each crystal in a close-fitting hole in a plate of copper or iron of equal thickness and rolling the plate and crystal together. About one-third of the crystals were rolled in a "sandwich" pack by adding top and bottom cover plates. The two-high mill used had 8-in. diameter rolls and was operated at 15 r.p.m. The initial diameter of the crystals was between 1/4 and 1/2 in., while the starting thickness varied from 0.031 to 0.376 in. With a single exception, which was rolled 63 per cent, the crystals were rolled to a final reduction in thickness of 82 to 97 per cent in 20 to 40 passes, alternately changing the sense of the rolling direction. The initial orientations of the crystals were determined either by X-ray back reflection12 or by optical reflectionl3 from etch pits; the mean final orientations were determined by X-ray Laue photograms using molybdenum, silver, or tungsten radiations, by optical reflection, and in many cases by both methods. Results Twenty-six crystals were studied. It was found that there were three typical be-

Jan 1, 1941

By William T. Schneider, Taylor Cole

Drilling in West Texas during 1941 was more active than in any year since 1937, a total of 2325 wells having been drilled. Pre-Permian exploration was the greatest in the history of the area; 106 wells tested pre-Permian formations during the year. Wildcatting reached the peak since 1937, with 135 wildcats, of which 20 per cent were producers. The wells were drilled to a greater average depth than in any previous year. Slim-hole drilling was the common practice, using drilling equipment that is largely portable. Because of deeper drilling, more attention was paid to mud fluids, especially the use of materials to reduce water filtration. There has been slight improvement in the protection of the pay horizons while drilling by the use of reverse circulation, and drilling-in with oil as well as low water-filtration muds. The practice of setting and cementing the oil strings through the producing formation and perforating opposite the pay zones has increased in the fields producing from sands. It is doubtful whether this practice is of unusual value in dolomitic limestone fields. There have been few if any technological improvements in obtaining necessary information on the pay sections penetrated, by coring, core analyses, better sampling, and more detailed drilling time. However, more operators are beginning to realize the necessity of good samples. For a proper study of the reservoirs in West Texas, it is essential that better samples be obtained, that more core analyses be run, and that better methods of obtaining drilling time be initiated. It should be noted that increased drilling speeds and slim-hole drilling have tended to reduce coring and core recovery and have not aided in obtaining good subsurface samples. In fact, fast drilling speeds and slim-hole drilling have reduced the cost of drilling operations, but with the sacrifice of much needed subsurface information. Larger quantities of slower-reacting acid are being used per well. There has been improvement in shooting, in that a greater number of quarts per foot have been used and an attempt has been made to concentrate the shots opposite the pay zone. The use of mud logging to determine the characteristics of the pay section increased considerably over the year 1940. There has been a slight increase in obtaining reservoir information in the new fields, such as bottom-hole sampling, bottom-hole pressures, and records of gas, oil, and water withdrawals. However, there is great need for more data on these subjects, particularly accurate information regarding gas and water volumes. There are three repressuring projects and a fourth is nearly ready for operation in the Kermit field. There is one repressur-ing project in the Payton field and one in the North Ward field. So far, the gas-injection projects have not shown very impressive results. As yet, there are no water-flooding projects or water-disposal projects in West Texas. Not including gathering lines within the fields, 222 miles of feeder pipe lines were

Jan 1, 1942

By Taylor Cole, William T. Schneider

Drilling in West Texas during 1941 was more active than in any year since 1937, a total of 2325 wells having been drilled. Pre-Permian exploration was the greatest in the history of the area; 106 wells tested pre-Permian formations during the year. Wildcatting reached the peak since 1937, with 135 wildcats, of which 20 per cent were producers. The wells were drilled to a greater average depth than in any previous year. Slim-hole drilling was the common practice, using drilling equipment that is largely portable. Because of deeper drilling, more attention was paid to mud fluids, especially the use of materials to reduce water filtration. There has been slight improvement in the protection of the pay horizons while drilling by the use of reverse circulation, and drilling-in with oil as well as low water-filtration muds. The practice of setting and cementing the oil strings through the producing formation and perforating opposite the pay zones has increased in the fields producing from sands. It is doubtful whether this practice is of unusual value in dolomitic limestone fields. There have been few if any technological improvements in obtaining necessary information on the pay sections penetrated, by coring, core analyses, better sampling, and more detailed drilling time. However, more operators are beginning to realize the necessity of good samples. For a proper study of the reservoirs in West Texas, it is essential that better samples be obtained, that more core analyses be run, and that better methods of obtaining drilling time be initiated. It should be noted that increased drilling speeds and slim-hole drilling have tended to reduce coring and core recovery and have not aided in obtaining good subsurface samples. In fact, fast drilling speeds and slim-hole drilling have reduced the cost of drilling operations, but with the sacrifice of much needed subsurface information. Larger quantities of slower-reacting acid are being used per well. There has been improvement in shooting, in that a greater number of quarts per foot have been used and an attempt has been made to concentrate the shots opposite the pay zone. The use of mud logging to determine the characteristics of the pay section increased considerably over the year 1940. There has been a slight increase in obtaining reservoir information in the new fields, such as bottom-hole sampling, bottom-hole pressures, and records of gas, oil, and water withdrawals. However, there is great need for more data on these subjects, particularly accurate information regarding gas and water volumes. There are three repressuring projects and a fourth is nearly ready for operation in the Kermit field. There is one repressur-ing project in the Payton field and one in the North Ward field. So far, the gas-injection projects have not shown very impressive results. As yet, there are no water-flooding projects or water-disposal projects in West Texas. Not including gathering lines within the fields, 222 miles of feeder pipe lines were

Jan 1, 1942

By M. E. Wadsworth, R. C. Peterson, W. M. Fassell

The temperature and pressure dependence of the reaction of tantalum in oxygen were investigated from 500° to 1000°C at pressures from 10 mm Hg to 600 psi total oxygen pressure. Tantalum was found to oxidize linearly under the above conditions. Three distinct regions of temperature dependence were found with different energies of activation. From 500° to 600°C the rate of oxidation of tantalum was found to be essentially independent of the oxygen pressure at the pressure investigated. The oxidation rate increases rapidly with an increase in pressure from 600' to 800°C. The dependence of the oxidation rate on the bulk concentration may be expressed by V = k'?, where k' is the specific rate constant and ?=k1Co2/(l + K1Co2), where k, is the equilibrium constant for the adsorption of oxygen on tantalum. ONLY a limited amount of data has been presented in the literature on the oxidation behavior of tantalum metal. Some values of its oxidation rate were reported in the Corroston Handbook' and by McAdams and Geil.' The first extensive investigation of tantalum was the work of Gulbransen and Andrews." They determined the reaction rates of tantalum in O2 and N2. Their results indicate that this metal follows the parabolic law in the temperature range of 250" to 450°C in O2 at pressures of 7.6 cm Hg with an activation energy of 27,400 cal per mol. In nitrogen, the metal follows the parabolic law from 500" to 800°C at 7.6 cm pressure. All experimental determinations were of 2 hr or less duration and deviations from the parabolic rate conceivably could occur at longer times. A spectrophotometric study of the oxidation of tantalum by Waber, Sturdy, Wise, and Tipton' indicated good agreement between this method and the microbalance technique. The experiments were conducted in air from 220" to 350°C. The metal was found to follow the logarithmic law up to 320°C and the parabolic law at higher temperatures. The activation energies in the logarithmic region were reported as 12.57 kcal per mol and 12.0 kcal per mol, respectively, for the microgravimetric and spectrophotometric methods. In the parabolic region the activation energy was found to be 27.2 kcal per mol, in good agreement with the value of Gulbransen and Andrews." The present paper is concerned with the behavior of tantalum from 500" to 1000°C in oxygen at pressures ranging from 1/2 to 40.8 atm pressure. Earlier preliminary data by McKewan5,6 indicated the following facts concerning the behavior of tantalum: 1—At temperatures from 500" to 600°C, the metal followed the linear law. 2—At 575°C the rate of oxidation was found to increase with O2 pressure. 3—The Arrhenius plot in this temperature region was nonlinear. The nonlinearity of the Arrhenius plot was indicative of a more complex behavior than originally suspected for this metal.

Jan 1, 1955

By Craig E. Saporito

INTRODUCTION Freeport-McMoRan Inc. has been very active recently with two major discoveries and its restructuring activities. This paper describes Freeport-McMoRan's businesses, the two major mineral discoveries, and exciting opportunities within the oil and gas operations. BUSINESS ACTIVITIES Freeport-McMoRan is the largest and one of the lowest cost fully integrated U.S. phosphate fertilizer producers. It is the second largest domestic Frasch sulphur producer. Freeport- McMoRan will become the largest domestic producer of Frasch sulphur when its Main Pass Block 299 sulphur deposit reaches full production in 1993. Furthermore, it is the largest transporter of sulphur produced by others. Its oil and gas activities rank among the largest U.S. independents in terms of production and proved reserves. The copper/gold operations in Indonesia are among the world's lowest cost. When expansion operations reach full capacity levels in 1992, the Indonesian copper/gold complex will be the fifth largest copper operation in the world. Operations are divided into three business segments that include: 1. Agricultural minerals, incorporating sulphur, phosphate rock and phosphate fertilizer activities; 2. Energy, including oil and gas activities; and 3. Metals, incorporating copper, gold and silver operations in Indonesia. In early 1989, Freeport-McMoRan announced the discovery of two world-class ore bodies; a sulphur deposit off the coast of Louisiana on Main Pass Block 299, and a copper/gold deposit -- the Grasberg in Indonesia -- approximately two miles away from the existing Ertsberg East operations. As a result of these major discoveries, Freeport- McMoRan decided to carry out a restructuring program. Its purpose was to sell $1.2 to $1.5 billion of non-strategic assets. Debt levels and associated interest expenses will be significantly reduced, and general and administrative expenses will be reduced, which will place Freeport- McMoRan in an excellent position to fund the development of the Main Pass Block 299 sulphur discovery, the Grasberg discovery, and oil and gas discoveries. This restructuring program also will allow Freeport-McMoRan to achieve the greatest future value for shareholders by focusing on its principal businesses (Figure 1). Strategic Restructuring • Sell $1.2 - $1.5 Billion Of Non-Strategic Assets • Significantly Reduce Debt • Significantly Reduce G&A • Fund Development Of Main Pass & Grasberg • Stronger Company; Positioned For Future Growth • Focus Is On Principal Businesses: - Sulphur/Phosphate Fertilizers - Indonesian Copper/Gold - Oil And Natural Gas Figure 1 - Strategic Restructuring AGRICULTURAL MINERALS Main Pass Block 299 Discovery The Main Pass Block 299 discovery has a proven reserve of 67 million long tons of recoverable sulphur. This is the largest known Frasch sulphur deposit in North America. The discovery increased Freeport-McMoRan's sulphur reserves more than five-fold, and is synergistic with the company's phosphate fertilizer assets. The

Jan 1, 1990

By William Newnam

WHEN Hugh Lee Pattinson discovered, in 1829, that the crystals formed during the slow cooling of molten lead were poorer, and the remaining liquid richer in silver, than the original lead, an important step was made in the metallurgy of this metal. Being the first process applicable to the desilverization of low-grade lead bullion, it soon found its way into all European countries having such a product to treat, thereby effecting the saving of many ounces of silver annually which previously had been thrown away. The old hand process was expensive, as viewed from the standpoint of more modern methods; the labor was great anti the tonnage was small, but on the other hand the results were fairly, satisfactory. This process flourished for some time after the introduction of the cheaper Parkes process in 1852 and it is still in use in a few European smelteries. Only one notable improvement was made on the original process, that of Luce and Roan at Marseilles, France. It consisted in the application of steam for stirring and the tapping of one-third of the liquid lead, through perforated plates covering the tap holes flush with the bottom of the kettle, thus leaving two-thirds in the form of crystals in the original kettle. This modification considerably lowered the operating costs as it permitted of much larger kettles, an increased tonnage and eliminated much of the slow, hard labor of the hand process.. The Luce and Rozan process has persisted in its original form to the present clay. Stephen Tredinnick, English born, spent most of his years around the Luce and Rozan plants at Marseilles and elsewhere in Europe, coming later to Eureka, Nev., in 1878, to operate the Luce and Rozan plant at that point. Mr. Tredinnick was a competent Luce and Rozan operator and being devoted to the process he firmly believed that with modifications the costs could be so lowered as eventually to supplant the Parkes process.

Jan 5, 1917

By G. W. Healy, J. C. Schottmiller

Molten silicates were found to exist in the Cr-Si-0 system at temperatures above 1450°C. one atom of oxygen is readily removed from CrzOs in the presence of Si02 at 1700°C, forming a silicate melt. Steam-hydrogen ratio measurements made at this temperature indicate that the free energy of the reaction: Cr20s(c) + Hz = 2CrO (in Si02 -saturated melt) + H20 is approximately 5600 * 1500 cal. A deep-blue chromous silicate, probably Cr2Si04, forms from these melts at about 1400" to 1500°C, and is characterized by.its distinctive X-ray diffraction pattern and optical properties—distinct pleochroism and high refractive indices. THE question of the state of oxidation of chromium in slags has vexed metallurgists for many years The experiments of Koerber and Oelsenl suggested the probable presence of divalent chromium in silica-saturated slags equilibrated with high-chromium melts. Hilty and coworkers2 had also found chromium at lower valency, as Cr304, in inclusions formed from oxygen-saturated Fe-Cr melts with as little as 10 pct Cr. In both cases, disproportiona-tion of the lower oxide to CraO3 and chromium was found to occur to a greater or lesser extent, depending upon the rate of cooling from the high temperature. The work on Cr304 was sufficiently detailed for chipmans to derive its thermodynamic properties, but Oelsen's experiments in the silicate system were not extensive enough since most of his runs were made with slags containing large amounts of manganese oxide in addition to iron and chrome oxide and silica. The present study describes experiments carried out to map out an approximate liquidus diagram in the CrzOs, "CrO", SiOa portion of the Cr-Si-0 system, and to measure the partial free energy of solution of oxygen in the system. EXPERIMENTAL 1) Approximate Melting-Point Determinations. Preliminary trials showed that when an equimolar mixture of Cr20s and SiOa was treated with hydrogen in the temperature range 1500" to 1600°C, copious amounts of steam were evolved, and a low-melting liquid formed which could be quenched to a blue, crystalline, material having a distinctive X-ray diffraction pattern. It was found that the identical material could be produced by heating intimately mixed, finely divided Cra03, Cr, and SiOa, held in a tungsten crucible, under purified argon. Thus, it was possible to prepare mixtures containing any desired proportions of chromium, silicon, and oxygen, pel-letize them, heat to temperature in the furnace shown in Fig. 1, and observe, after cooling, whether the pellet remained unchanged or showed signs of incipient, partial, or complete melting. 2) Free Energy of Solution of Oxygen. This was studied by measurement of steam-hydrogen ratios for the reaction: H20 (gas) + O (dissolved in charge) + Ha (gas) The experimental method chosen was to prepare a

Jan 1, 1964

By C. H. Hitchcock

The puiblication by the Institute of a small geological map of the United States calls for an explanation of its peculiarities. The title intimates that it is intended "to illustrate the schemes of coloration and nomenclature recommended by the International Geological Congress." By way of further explanation it is said to be "based, by permission of the Director of the United States Geological Survey, upon the map published in his Fifth Annual Report, the portions not colored in that map being here supplied from other sources." The map referred to was prepared by W. J. McGee, and in the text of the report containing it he has given a list of the authorities employed in the compilation. The scheme of coloration used for the map was the one proposed by the Director, in the Seeond Annual Report, for the publications of the United States Geological Survey, which differed materially from those employed by the older American geologists. Because of the increasing diversity in the particular colors employed to represent rocks by geologists in different countries, and of the existence of very dissimilar schemes of nomenclature, it seemed best to the American Association for the Advancement of Science, at its Buffalo meeting in 1876, to appoint an international committee of geologists, who should consult together, and, if feasible, to call an International Congress to discuss these subjects. The proposition met with favor, and the meeting was called. The first session was held at Paris, in 1878, when geologists were present from twenty different countries. Once organized, the Congress has perpetuated itself, enacting regulations for its conduct, choosing the French language for its medium of communication, and arranging for the compilation of a geological map of Europe upon which the perfected schemes of coloration and nomenclature will be delineated. The American Association maintains a standing committee to represent it at the international sessions, and to report their proceedings. Sixteen countries were represented at the second Congress, at Bologna;

Jan 1, 1887

By R. M. Daelen

In recent years many new appliances have been introduced into German steel-works and rolling-mills for the purpose of improving working-methods, and of creating and maintaining increased production, and satisfying the ever-growing demand for metal of closely specified hardness, strength and form. One result of the improvements has been to aid very effectively in demonstrating the real superiority of ingot- over wrought-iron for almost every possible purpose, and in dispelling the last vestiges of prejudice unfavorable to the new metal. If, nevertheless, no marked decrease in the number of puddlingfurnaces has yet been noticed, the cause of their survival must be attributed to the greatly increased consumption of all kinds of ironmanufactures. Several large new works for the production of ingotiron are now, however, in course of erection in the Rhenish-Westphalian district, and upon their completion a rapidly diminishing output of wrought-iron may be anticipated. The present aim of all large works manufacturing ingot-iron is to work the molten blast-furnace pig into a finished product without any further fuel-consumption than is required to furnish steam for the rolling-mill. Though practice has established the feasibility of this principle, no works can yet point to its complete adoption, partly because of the limitations imposed by existing conditions and plant, and partly, also, on account of the highly-diversified character of the finished products. The Bessemer-works were the first to feel the influence of the basic process; but of recent years a similar influence has affected the open-hearth, and the owners of works possessing both a converterand an open-hearth plant are now seeking to arrange them for combined working, in charging as well as in casting. In small works the basic-lined reverberatory furnace is constantly gaining ground over the old puddling-furnace. The small basic converter, on the

Jan 1, 1891

By R. L. Segall

AN unusual thermal etch figure in copper is described and an explanation in terms of twinning is suggested. A flat polycrystalline specimen of OFHC copper cut from a rolled sheet was electro-polished in orthophosphoric acid and annealed at 950°C in a vacuum of approximately 10-3 mm Hg for 2 hr. The specimen was found to be thermally etched, the markings on the surface being consistent with the assumption that they were the traces of the (111) planes which are developed preferentially because they have the lowest free energy. However, on one grain (the grain shown in Fig. 1) the traces formed an almost regular pentagon and at first sight it seemed unlikely that they could all be (111) traces. These traces were studied further because it was thought that they might be a type of growth spiral. A fringe pattern showed that this was not so, the grain being sensibly flat and the only features having steps were the striations and the faint curved line passing out from the center of the pentagons. To obtain some additional information, the specimen was deformed in tension. The effect of the stress was first to cause the appearance of lines running from the centers to the apexes of the pentagons and then to tilt the five segments so formed. At a much greater stress, appreciable slip appeared on the grain; these effects can be seen in Fig. 2. The micrograph was taken at a fairly late stage in the deformation and the tilting is quite marked. The magnification is the same as in Fig. 1, and although some slip can be seen it could be observed better by varying the illumination and using higher magnifications. In each segment of the grain, slip (which takes place on the (111) planes) was parallel to the side of the pentagon in that segment. The marked changes in direction of slip from segment to segment seemed to be incompatible with the presence of a regular array of subgrains. These results suggest that some of the five segments were twins. If this is so, since the twinning plane in copper is the (111) plane, the radial lines must be traces of the (111) planes on the surface. From the symmetry of the striations about the radial lines, these planes must be almost perpendicular to the surface. The angle between <III>directions in face-centered-cubic copper is 70&apos;32&apos;. If, in Fig. 3, OAB (triangle 1) is taken as matrix and OA, OB are (111) planes viewed edge on, then AB is in the correct direction to be the trace of either of the other two (111) planes on the surface. If triangle 2 is the twin (about the (111) plane perpendicular to the surface and containing OB) of triangle 1, then once again it can be shown that all lines are traces of (111) planes. Similarly, triangle 3 is the twin of triangle 2, 4 of 3, and 5 of both 4 and 1. (The sequence is, of course, quite arbitrary.) However, if this were the case there would be a discrepancy of 7&apos;20&apos; to be accounted for. It is suggested that the faint curved line passing outward from the center of the pentagon represents either a low angle boundary or a sixth small twin. The slight step shown by the fringes at this line might be an indication that the former is the case. This explanation does not account for the coincidence of obtaining a grain whose surface must be so close to (110) and obtaining the curious twinning described previously; it would be of interest to find a specific mechanism for this.

Jan 1, 1958

By George Rice

INSTANTANEOUS outbursts of gas in underground workings are similar in effect to great blasts of explosives, but without heat effects. Fortunately they occur only in a few localities in exceptional coal fields of the world and under exceptional geologic conditions. Such violent outbursts should not be compared with the ordinary outflows of gas into coal mines or with explosions of gas and dust. The phenomenon is essentially one of gas held in circumscribed areas under very high pressure and as a mining face or heading approaches such a place and the mining excavation sufficiently weakens the natural surrounding dam or shell, this is burst by the pressure just as by the discharge of a mass of explosives. The outbursts, so far as known to the writer, have been confined to coal beds and have not occurred in other mineral deposits. Hence, as discussed later, he believes that it is the relation of the gases to the coal material that is a factor in conjunction with others in producing conditions which permit the phenomena to occur when mining is done. The gases in most instantaneous outbursts have been hydrocarbon gases but in two coal fields they have been definitely found to be chiefly or wholly carbon dioxide. One of these localities in which CO2 outbursts have been frequent and have caused loss of life is in the southern part of the Gard basin, near Alais, in southern France. In 1919, the writer visited the Fontaine mine in this field the day following the occurrence of an outburst by which two men were smothered by carbon dioxide and fine dust. After 24 hr. the CO2 had not been entirely removed by the ventilating current. Occasional outbursts of CO2 have also occurred in other small basins in France, causing accidents, as in Puy-de-Dome. However, mines in the Gard basin, north of those in which CO2 outbursts have occurred, have experienced hydrocarbon gas outbursts.

Jan 1, 1931

By Peter J. Maxworthy

INTRODUCTION There is no hard and fast rule on whether functions within a company, diversified or otherwise, should be strongly centralized or decentralized. In all diverse organizations, there are certain basic functions which remain common (or central) to each element of the business, viz: Personnel Management Cash Management Taxation Management Legal Planning Accounting Standards It would follow that each of these common factors requires some supervision at a central level to ensure that overall group objectives are met. It is true that other functions including: Industrial Relations Marketing and Distribution Production Research and Development Purchasing Management Accounting may also be common to each element of the organization. However, there is far less commonality in the degree to which these functions are central to the efficient performance and financial well-being of the business. Role of Operating Units The resources of operating centers may be viewed as a bank of funds, the nature of which can be changed from time to time, but the employment of which must provide for ongoing increases in the net worth of the total enterprise expressed in terms of market values. Operating units are required to continually review products, methods, and opportunities and to monitor avenues for incremental investment--all with a view to attaining the necessary additive net present value of future cash flows of the enterprise. Operating units should be permitted sufficient autonomy to enable the best use to be made of the skills and experience of the people it employs in order to produce a return appropriate to the value of assets employed. Role of Head Office The head office will typically comprise a specialist group--the leaner the better if one strongly adopts the decentralist approach--often acting as Service Centers but also performing a control function in the corporate sense. The head office function is a cost center. It may be instrumental in developing strategies for increasing revenues or reducing costs on a group scale, but it does not generate revenue. Every dollar spent on this function is an extra dollar to be generated by the operating centers in order to achieve an increase in corporate wealth. TREASURY MANAGEMENT Treasury management is concerned with the provision of finance, cash-flow management, and risk analysis. Each decision taken within the enterprise has a cash implication. It follows that a well-integrated central Treasury function can, in all likelihood, produce economic benefits. The degree to which the function should be centralized depends largely upon the unique nature of the operating units it is servicing. Levels of ownership, the calibre of unit operating managers, and the nature and geographic distribution of the business are all factors determining the degree to which the Treasury function is centralized. In the case of Peko-Wallsend, the Treasury Department is small, comprising four people. While divisional cash-flow management is largely decentralized, Treasury is responsible for the daily management of funds surplus to the immediate needs of operating units. Treasury also operates as central banker and provides funds to

Jan 1, 1985

By John I. Yellott

SINCE the days of Newcomen and Watt, when men first sought to turn the energy of fuels to useful purposes, coal-generated steam has supplied most of the power needed for both stationary and mobile applications. The low efficiency and large water requirements of the nineteenth century steam-power plant caused many engineers to turn their thoughts toward more direct means of converting heat into power. As far back as 1791, John Barber secured an English patent on a combination&apos; which he might well have called a "gas turbine." He proposed to generate procducer gas from coal or charcoal, to burn it under pressure in air obtained from a reciprocating compressor, and to drive a turbine wheel with the resultant hot combustion products. With the optimism characteristic of the inventor, he hoped that the turbine would not only operate his compressor but also perform useful work. There is no record that Barber ever built his machine, but if he had done so he would have learned that useful power can result from such a combination only when both turbine and compressor are highly efficient and when the temperature of the gas entering the turbine is not far below 1000°F. Hot-air prime movers continued to attract attention, and both Stirling in England and Ericsson in America2 built reciprocating engines that operated with some success upon coal-heated air. The internal-combustion engine, burning liquid fuels, supplanted the hot-air type, and, for the first time, challenged the supremacy of both the steam cycle and its familiar fuel, coal. LIQUID FUELS COMPETE WITH COAL As the increasing use of the automobile multiplied the demand for gasoline, the supply of residual fuel increased rapidly, and heavy oil declined in price to the point where it became competitive with coal. First in the marine field and later in stationary plants in areas adjacent to refineries, oil began to be widely used. Oil&apos;s greater convenience and higher heating value per pound of weight or per cubic foot of bunker space have caused it to take over much of the marine field. The introduction of the highly efficient diesel engine, capable of burning a fuel that is cheaper than gasoline, again threatened the position of coal, for the operating costs of the diesel became directly competitive with those of coal- burning equipment. In isolated power plants and smaller marine installations, the diesel provided the medium by which oil again successfully invaded fields formerly dominated by coal. The diesel engine, provided with an

Jan 1, 1946

By A. T. Robinson, J. E. Dorn

The electrical resistivities of aluminum alloys containing CU, Ge, Zn, Ag, Cd, and Mg were found to increase linearly with the atomic percentage of the solute atoms. Application of Linde&apos;s rule to these data suggests that each aluminum atom contributes 2.5 electrons to the metallic bond. ALTHOUGH aluminum invariably exhibits a Jt\. valence of three in ionic solids, it does not follow necessarily that its valence in the metallic state is also three. As a matter of record, many properties suggest that the number of bonding electrons in metallic aluminum is less than three. For example, as shown in Fig. 1, the atomic radii1 of the metallic elements in the solid state decrease with increasing atomic number at the beginning of any one period. The atomic radius of aluminum, however, is greater than that which would result from a regular decrease in atomic radius with increasing atomic number, suggesting that the number of bonding electrons in aluminum is somewhat less than three. Correlated with the anomalously large atomic radius of aluminum is its abnormally low melting temperature. As the atomic numbers increase in any one period, the melting temperatures of the metallic elements increase.&apos; As shown in Fig. 2, however, the melting temperature of aluminum (13) is only slightly greater than that of magnesium (12). Again the number of bonding electrons in metallic aluminum appears to be nearer two than the expected value of three. In addition Ageev and Ageeva3 alculated the electron density distribution in the aluminum lattice. A comparison of such electron density curves for various assumed valence states of aluminum with experimentally determined curves suggests that the actual number of bonding electrons in metallic aluminum is between two and three. Hume-Rothery and Raynor&apos;, " have suggested that the above-mentioned abnormalities are associated with the overlapping of the Brillouin zones of metallic aluminum when it is in the usual face-centered cubic structure. The importance of the number of bonding electrons in metals has been extended recently into the field of mechanical properties. While formerly it was thought that the plastic properties of alpha solid solutions were primarily dependent upon the lattice strain induced in the solvent by the solute, it is now known that the difference in the number of bonding electrons of the solute and solvent also has its influence on the plastic properties."1&apos; In order to achieve a satisfactory correlation of the effect of alloying elements on the plastic properties of aluminum alloys,"&apos;T however, it was necessary to assume that the number of bonding electrons contributed by aluminum was about two rather than the expected value of three. It appeared to be desirable, therefore, to seek other criteria for evaluating the number of bonding electrons contributed by aluminum to its alpha solid solutions, especially in view of the practical as well as the theoretical importance of the effect of valency on the plastic properties. Norbury&apos; was perhaps the first to illustrate that the increase in resistance of alpha solid solutions is associated with the differences in valence of the solute and solvent metals. In a series of illuminating investigations Linden-&apos;&apos; has shown that the electrical

Jan 1, 1952

By E. C. Wright

THE following article is based on observation of college graduates entering the steel industry in technical work made during the past 25 years, the first five of which were spent as a college instructor in two engineering schools, and the last 20 in the employ of a large steel company that has hired hundreds of engineering graduates for steel-mill operations. The college graduates encountered during this period have come from many, colleges representing schools in Eastern States, Midwestern Universities, many Southern colleges, and many smaller colleges and normal training schools mostly in western Pennsylvania and Ohio. The college training of these students for engineering work naturally has varied widely and the educational qualifications of the entrants have been in many ways different. It was found at an early date that graduates of standard engineering colleges were much more adaptable than graduates in science from nontechnical schools. The engineering students seemed to be more suited to actual work in steel&apos; plants and in general were better able to grasp a knowledge of the operations they observed. However, although the graduates of engineering schools have had somewhat better training -in physics, mathematics, and engineering, it has been a general and continual observation that most of the students employed have had inadequate training in the fundamental sciences. Since this discussion relates entirely to metallurgical engineers, it should be emphasized that students taking metallurgical engineering courses in college seem to be poorly trained in organic chemistry, physics, physical chemistry, thermodynamics, and any higher form of mathematics than simple calculus. It has been noted frequently that young engineers faced with problems in a mill that involve some mathematics generally flounder badly, and that they have little conception of physical chemistry. Another common deficiency lies in the young graduate&apos;s lack of knowledge of where to look for the more detailed literature on any subject. He reverts instinctively to some college textbook whose coverage is usually very elementary. It is recommended that such textbooks contain a bibliography of the source literature, and that students be taught to use theoriginal data. Many of the students had had previous courses in college dealing with metallurgical work such as steel melting, metallography, etc., but it was found that their grasp of these subjects was extremely sketchy. It was soon realized that an ordinary engineering graduate could be taught more about steel melting and manufacturing processes in a, few weeks in a. plant than he could learn in a college course on such subjects. A similar statement may be made regarding the ability of students to conduct laboratory work. Their lack of technique and skill in handling equipment and setting up experiments was soon apparent. It became neces-

Jan 1, 1946

By Ferit Gurses

EXTENSIVE coal and lignite deposits exist in Turkey. Bituminous coal is the nation&apos;s principal mineral resource; important not only as fuel for the industrial development of the country, but also as a means of obtaining foreign exchange. Of the electrical power generated during 1939, 82.8 per cent was derived from coal.1 It is anticipated that the lignite deposits will be one of the major sources of power for the electrification of the country. BITUMINOUS COAL The locations of the four principal bituminous-coal2 basins are indicated on Fig. 1. The Eregli-Zonguldak basin lies on the Black Sea northwest of Ankara; the Canakkale basin lies near the junction of the Dardannelles; the Trakya basin is in European Turkey northwest of the Bosphorus and the Erzurum basin lies far to the east. The Eregli-Zonguldak basin is the most important of the four. This coal basin was discovered in 1829 but did not arouse interest until 1848; up to 1865, its annual production had not exceeded 50,000 metric tons. In 1865, during the Sultanate, working of coal mines was started by the Navy department, and the annual production was 61,145 metric tons. In 1908, the Minister of Commerce and Agriculture was authorized to develop the whole coal basin. Production reached 264,397 metric tons in 1910, and during 1915-1922, preceding the revolution, the total production of the basin was 2,676,043, or an average of 334,000 metric tons annually. The period of national revolution that followed was marked by a steady increase in coal production in Turkey, although world production decreased, because of the crisis of 1929-1932, about 52 per cent. AREA AND GEOLOGY OF THE COAL BASIN The geology of the Eregli-Zonguldak area is not yet completely known. The basin begins at Gungazi, to the west of Eregli, and extends to Sogutozu, a distance of about 106 miles. The coal beds, however, appear only in places and the overlying Cretaceous strata hide them elsewhere. This area includes the most important centers, such as Kandilli, Alacaagzi, Teflenli, Kozlu, Gelik (see Fig. 2). The geological sequence of the district is correlated with the Cretaceous of the Balkans; which is, in turn, a prolongation of the Alpine zone. Geological surveys made by G. Ralli, R. Zeiller and P. Arni3 show that the Eregli-Zonguldak formations fall into three natural divisions. Series a, The Alacaagzi in the district of that name (Fig. 2), is of the Culm stage. The strata strike generally east-west and dip about 30° south. This series appears also around Kandilli and Camli, with a steeper angle of dip, but the deposits there lack regularity. The Alacaagzi stage appears also farther east, to the south of Kozlu and Gelik. The Alacaagzi series contains 15 seams of an average thickness of 2 ½ ft. of good coal. Series b, the Kozlu, best represented in Zonguldak, Kilimli, Catalagzi, and between

Jan 1, 1944

By Mark J. Klein, Robert A. Haggins

The pesence of a small amount of oxygen was found to cause significant grain growth restraint in 99.99 pct Ag. This behavior does not seem to be due to the presence of an oxide dispersion, but instead, to be related to the existence of minute amounts of oxygen m solid solution. In the amounts necessary to cause the observed effects it was found that oxygen migrates with extreme rapidity, probably along extended structural imperfections, such as dislocations and grain boundaries. A number of years ago, hastton&apos; observed that the presence of small amounts of oxygen caused a retardation of grain growth in silver. He attributed this behavior to the formation of a fine dispersion of oxide particles by the internal oxidation of trace impurities. More recently, wood2 also found that oxygen caused grain growth restraint in copper. Experiments using both copper and a dilute solution of aluminum in copper led to the conclusion that the effects observed in copper were due to oxygen in solid solution, rather than an oxide dispersion. During the course of a study of the influence of several solutes on the recrystallization of Silver, the presence of minute amounts of oxygen was found to exert a very significant influence on grain growth. The experiments reported here were undertaken to determine whether the grain growth restraint observed in silver due to the presence of oxygen is related to oxygen in solution or to an oxide dispersion. Because of the difficulty in measurement and control of the very small oxygen concentrations causing the observed effects no attempt was made to treat the data in a quantitative manner. EXPERIMENTAL PROCEDURE AND RESULTS Silver of 99.99 pct purity was melted and cast into slabs in a vacuum of better than 0.1 p. These slabs were reduced 50 pct by cold rolling to a thickness of approximately 2.5 mm. Samples cut from this material were annealed in vacuum for a series of different times at 803°C. Another group of samples was similarly annealed in air. This temperature is well above the recrystallization range for silver of this purity (150" to 200°C). The mean grain diameter of these samples was measured, both in the center and near the edge, using the line-intel-cept method, and is shown as a function of annealing time in Fig. 1. The grain size in the centers of the samples annealed in air was found to be larger than that of the surface regions, while the grain growth behavior of the edge and center regions annealed in a vacuum was approximately the same. he edge measurements were taken at a distance of 0.2 mm from the surface.) A few samples were annealed in nitrogen. Their behavior was identical to that of the vacuum-annealed samples. Samples annealed in oxygen had approximately the same grain growth behavior as those annealed in air, leading to the conclusion that this behaviouer is due to oxygen. The microstructure of a sample annealed in air at 803" for. 30 minutes is shown in Fig. 2. The smaller grain size near the surface is characteristic of the iir-annealed specimens. Possible causes of this grain growth restraint in the air-annealed specimen are the formation of an im-

Jan 1, 1962