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Jan 1, 1956

By A. H. Daane, J. F. Haefling

BECAUSE of the wide use of platinum in industry and research, the physical properties of this metal, including its vapor pressure, have been studied in some detail.' The other members of the palladium-platinum group of metals have not been studied as extensively, and only qualitative information is available on the vapor pressure of palladium. Data given in literature by Vines1 and Brewer2 on the vapor pressure of palladium are based on the qualitative observations by Holborn and Austin3 and Crookes4 on the rate of volatilization of palladium filaments in various atmospheres. The general observation that palladium is the most volatile metal of the palladium-platinum metal group was corroborated by Bell, Love and Normand who studied the separation of isotopes of the platinum-group metals by a mass spectrometric method. We have measured the vapor pressure of palladium using the Knudsen effusion technique. In this work, the effusion vessel was suspended from a quartz-fiber microbalance into an induction furnace, and the amount of vapor effusing from the vessel was determined by direct weighing of the vessel during the measured heating times. This technique has been described in a report from this laboratory." The vapor pressure of palladium was calculated from these measurements using the equation P...... = 17.14 -W- (77m)'u [1] a t where ? is the weight loss in grams of vapor of molecular weight m from a vessel having an orifice of a sq cm, during t sec. The derivation of this equation from kinetic theory has been described in a previous report from this laboratory: as well as in texts discussing the kinetic theory of gases.%" Test Vessel—In the search for a suitable material for the effusion vessel, it was found that tantalum reacted with palladium metal to form intermetallic compounds, and graphite was readily dissolved in palladium metal to form what appeared to be a liquid phase at a temperature several hundred degrees below the melting point of palladium. On cooling, the graphite gathered into spherical balls in the palladium, with crystals extending radially from the center of these balls, some of which were a millimeter or more in diameter. However, palladium metal vapor did not attack the graphite vessel, so graphite could be used where it did not contact condensed palladium. Tungsten did not appear to react with palladium vapor or molten palladium at its melting point, but it was not convenient to use a tungsten-vapor pressure vessel because of the difficulty of fabricating this metal. Since the vapor-pressure range to be studied (10 2 to 10 ' mm) did not appear to extend above the melting point of palladium, a combination of tungsten and graphite served to provide a very satisfactory effusion vessel. The lower half of the graphite vessel was lined with some strips of tungsten foil and the sample of palladium consisting of a coil of sheet was placed in the tungsten liner; in this way, no contamination of the palladium by carbon occurred. Procedure After outgassing at 1500C, the tungsten-lined graphite effusion vessel was loaded with 300 mg of

Jan 1, 1959

By Cyril Smith

A COMPLETE discussion of the literature on the subject of the influence of copper on iron and steel will be published elsewhere.1 The present paper is concerned especially with the precipitation-hardening of copper steels, and brief mention will be made here only of the work of Kin-near,2,3 Nehl4 and Buchholtz and Koster,5 who alone have studied this phase of the subject. Kinnear found that normalized low-carbon steel castings containing about 1.0 per cent copper on drawing at temperatures in the neighbor-hood of 530° C. (1000° F.) increased in tensile strength and yield point, with little decrease in ductility. The maximum effect was obtained with about 0.9 to 1.0 per cent copper, and when the copper exceeded 3 per. cent no improvement occurred on reheating. Kinnear did not study the effect of time of reheating-an all important factor where precipitation is concerned. Nehl,6 who apparently was unaware of Kinnear's work, recognized the change as due to precipitation and studied the interdependence of time and temperature of reheating, the temperature of the initial solution heat treatment, and the speed of cooling necessary to retain the bulk of the copper in supersaturated solu-tion and to give an increase in hardness and tensile strength on reheating. Nehl found that if the final rolling or forging temperatures exceeded 700° C. (1300° F.) it was not necessary even to normalize the steel, but full precipitation occurred on merely reheating the forged or rolled shapes at 500° C. (930° F.).

Jan 1, 1933

By Raymond H. Young, Paul Sennett

INTRODUCTION Kaolin clay, consisting largely of the mineral kaolinite, is widely used as a white pigment. In the United States, for instance, pigment kaolin production was nearly 6,000,000 tons in 1976 (1). Production for this year should be significantly above this level. Current prices for kaolinite 'pigments range from about $20.00/ ton to$260.00/tony,depending on the amount of processing needed to make the final product. Although much of this pigment kaolinite is used as an inert filler where product specifications are not very rigid, a large quantity of kaolinite is converted to products where very restrictive specifications exist. These specifications set severe limits on such properties as viscosity in a water suspension, particle size distribution, color, and brightness. This discussion will concentrate on methods available to improve the color and brightness of pigment kaolin and will review the advantages and problems associated with these various methods. The term "brightness" refers to the reflectance of the pigment to blue light (2). Since even the brightest commercial kaolins have a somewhat yellowish color, the blue reflectance (or brightness) is a reasonably good measure of their nearness to a perfectly white material. I KAOLINITE STRUCTURE AND SOURCES The mineral kaolinite is an aluminum silicate and can be represented by the formula (OH) 8Si4A14010. The formula is frequently written

Jan 1, 1979

By K. S. Krishnam, A. G. Guy

VOLUME 6 of the Transactions of the Baikov Institute of Metallurgy, Moscow, is devoted to the subject of "the experimental and theoretical study of the physical characteristics of dilute solid solutions,11 and summarizes work that has been done largely in the years 1958-9. In view of the attention that Soviet investigators have given to this subject, it seemed useful to carry out an independent experimental investigation in an effort to judge the scientific basis and practical significance of this field of study. The present note is a preliminary report of this investigation. The first property studied by the Soviet group was X-ray spectra of solid-solution alloys.' An anomaly observed at low concentrations (--0.05 at. pct) of the alloying element led to the theory that each impurity atom in a transition-metal base alloy is the center of a "block" of affected atoms with a radius of about 10"7 cm. This theory was further developed in a later paper.2 By this time similar anomalies had been found in diffusion coefficients3 and in thermal expansion.4 The entire development up to 1959 was reviewed in a comprehensive paper, and further theoretical ideas were also published at this time. Finally, the volume mentioned above was published in 19607 giving new experimental data on anomalies in optical properties and Hall constant, and a new theoretical treatment also appeared.' Although western scientists have done both theoretical work, summarized recently by Friedel,9 and considerable experimental work on dilute solid solutions, there is little support for the marked anomalies reported in the Soviet papers. Of the physical properties studied by the Soviet investigators, thermal expansion was chosen for the present investigation because of the relative ease of obtaining the necessary precision of measurement. A Leitz dilatometer was used for this purpose, and a special technique involving interchanging of the two specimens being compared permitted a precision of 0.05 x X in average thermal expansion over the range 27° to 600°C. The specimens were heated and cooled in vacuum or in a protective atmosphere at a rate of 50 °C per hr. Ferrovac E iron was used as the comparison specimen and in every case had a coefficient of expansion higher than (or equal to) that of the alloy. Since unintentional impurities are an important factor in studies of dilute alloys, special attention was given to the purity of the iron and the alloys used. The alloys were the same of those used by Abrahamson10 and by Michalak," and their preparation is described in these references. Chemical analyses of the Ferrovac E iron and of typical Fe-W and Fe-Mo alloys are given in Table I. The purity of the iron and alloys is undoubtedly higher than in the

Jan 1, 1962

Man is born on Mother Earth without knowledge or skills. Soon he finds physical needs for food, clothing, shelter, exercise, and relaxation. His personal needs are self-expression, new experiences, and amusements, while his social needs have been classified as work, status, security, friendship, companionship, and love. He finds himself infinitesimal in comparison to the whole. Often- times when he feels smug, he is actually riding for a fall. And nothing is much worse than frustrated man. The postwar world does not provide the Utopia of peace and prosperity of which man had dreamed. In fact, it seems that the sacrifices and waste of that great struggle are being lost in the morass of stupidity, selfishness, and cupidity which unfortunately are still the most conspicuous traits of the human race. Perhaps it is too soon to expect the blessiilgs which are supposed to appear in a peaceful world, and man's thought is clouded with a pessimism engendered by the conflict itself, in which all activities tend to enhance his pessimistic nature. Must man submit that it is a law of nature for nations to go to war? The war has demonstrated that when faced with a common danger, peoples differing in antecedents, language, forms of government, and resources can unite for a time, pool their skills and abilities, and emerge victorious from a contest unparalleled in magnitude, ruthlessness, carnage, waste, and cost. This has been accomplished by great individual and national sacrifices, the

Jan 1, 1950

The economic recovery of metals from dilute solutions has been the dream of mining engineers for many years. This subject is now receiving greater attention, particularly for copper, in view of the heightened demand for the metal and the tightening supply situation. A Copper Precipitation session, sponsored jointly by EMD Hydrometallurgy Committee and MBD, which took place during the Annual Meeting in March, heard papers on recent research and plant practice. Although the bulk of research in hydrometallurgy has been carried out in countries other than the United States1, producers in this country are making important contributions to the heap or dump leaching system. They realize that the processes are essentially simple to install and give high recovery rates at reasonable cost. Jacobi estimated in 1963 2 that the copper mining industry obtained a gross return from scavenging operations -on a worldwide basis-on the order of $20 million annually, subject to the usual deductions for refining and realization charges, overheads, taxes, etc.

Jan 6, 1966

By Julian Kennedy

When it was decided to erect these furnaces the company also decided to use the Cowper type of stoves. It was, however, desirable to improve upon the plan of the stoves then in operation, to avoid, if possible, some defects which had shown themselves in them. The stoves now in use at Furnaces " A," " B," and " C " are of the well-known type of Cowper stove, having a circular combustionchamber placed at one side of the stove, and a regencrator with crescent-shaped section, resting at the bottom oil cast-iron glatings, which are supported in turn by cast-iron girders, the products of combustion passing up the chamber, down through the flues of the regenerator, and thence to the chimney. The objection to this shape of stove, that the gases would not pass down the parts of regenerator lying beside and behind the combustion-chamber—the horns of the crescent, as it were,—did not apply to the newer form of stoves, with combustion-chamber having a straight wall next to the regenerator; but. there were other defects, the principal ones bring the small size of the openings through the regenerator and the material used for supporting it. The small passages (4" X 4") soon choked up, and when a part of them became entirely closed, not only was the effective heating surface greatly diminished, but as the remaining opening were not sufficient to absorb the heat

Jan 1, 1882

Institute of Metals Division Iron and Steel Division Extractive Metallurgy Division Council A W Thornton (ISD), Chairman, R W Shearman, Secretary, C S Barrett (IMD), J C Kinnear, Jr (EMD), John Chipman (ISD), J S Smart, Jr (IMD), A W Schlechten (EMD), M E Volin (MED), D S Eppelsheimer (MIED) Journal of Metals Editorial Advisory Committee J S Smart, Jr, Chairman, W A Dean, J J Golden,T D Jones, Evan Just, J C Kinnear, Jr, M Tenenbaum Pacific Northwest Regional Conference E R Marble, General Chairman, Marshall Huntting, Assistant General Chairman, W C Douglass, Mining Chairman, H C Hughes, Mining Chairman for British Columbia, W C Douglass, Mining Chair¬man for United States, Paul Billingsley, Geology Chairman, W D Nesbeitt, Miner¬als Beneficiation Chairman, H D Kelley, Industrial Minerals Chairman, J G Johnston, Metals Chairman, Lloyd Banning, Iron and Steel Chairman, W G Rouillard, Extractive Metallurgy Chairman, E C Roberts, Physical Metallurgy Chairman, D A Pifer, Mineral Industry Education Chairman, Frederick Brien, General Arrangements Chairman Metals Branch Membership Committee C M Squarcy, Chairman, R C Cole, Harold Mar¬golin, M E Nickel, S K Scovil Bylaws Committee A W Thornton, Chairman, W R Hibbard, Jr, J S Smart, Jr (IMD), John Chipman, T S Washburn (ISD), T D Jones, J D Sullivan (EMD)

Jan 1, 1956

By George Evans

DURING the past ten or twelve years, the average reader of newspaper and magazine articles has been led to believe that enormous deposits of high-grade coal exist in the northland and that these can be mined for practically nothing. But much of the reputed glitter and attractiveness of Alaskan coals disappears when viewed at close range. Many areas of coal-bearing rocks are widely distributed geographically from Cape Lisburne, on Bering Sea, to Admiralty Island south of Juneau. Bituminous coal is found at Cape Lisburne, on the Bering Sea, at Five Finger Rapids on the upper Yukon, and at Herendeen Bay and Chignik Bay; lignite is found on the Kobuck River, along the Yukon River from points near the mouth to Tonakat, near Rampart, at Dawson, on the east shore of Cook Inlet, and in the Tanana Valley, 50 mi. south of Nenana. The Susitna and Matanuska Valleys contain coal ranging from lignite to anthracite, and in the Bering Lake district, there are coals ranging from semi-bituminous to anthracite. No effort will be made to describe all of these fields, but the writer wile confine himself to the four principal fields, namely, the Nenana field, in. the interior of Alaska, tributary to the Fairbanks district; the Matanuska, field, in the Matanuska Valley; the Kachemak Bay field on the east shore of Cook Inlet; and the Bering River field, east of the mouth of Copper River.

Jan 2, 1921

THE record of the development of physical metallurgy since the founding of this Institute embraces by far the greater part of physical metallurgy as this subject is recognized today. Yet it is not to be supposed that the metallurgist interested in the properties and behavior of solid metals at the beginning of this period was without important and even fundamental information. He had an empirical knowledge of the behavior of solid metals which extended backward into prehistoric times and he had the early beginnings of many of the chapters in the science of metals. Industry was burgeoning in many directions, for methods had been developed, especially in the manufacture of steel that provided materials in extremely large tonnages, permitting applications of metallic materials on a very widespread scale. These multitudinous new uses of metals created an increased interest in the behavior of metals, and provided the basis for the rapid development of a science of metals. Indeed, the development of science generally that accompanied the industrial revolution reached a flood tide toward the end of the century, furnishing the metallurgist basic principles in chemistry, physics, mechanics, and crystallography that would shortly be extensively applied to metallic behavior. In this account, the early developments in the wide metallurgical field will be traced, in order that the status of physical metallurgy in 1871, when this Institute was founded, may be clearly seen. The subject of metallurgy in antiquity has been written upon frequently and at length. We shall here no more than indicate the main features that we need to define the position in 1871 and to provide a proper background for discussing subsequent developments. The writings of Pliny,1 23-79 A.D., to which Robex-ts-Austen3 fre-

Jan 1, 1948

A Report Of Current Activity In The Industry

Jan 6, 1951

FOLLOWING the presentation of the papers by Messrs. Mahan and Butler, the discussion printed below ensued. A. C. LANE* With particular reference to the New England con-sumer, I entirely agree with Mr. Mahan that intelli-gent marketing methods will do a good deal, but there is more than one way of improving them. For instance, coal can be shipped best to New England about this time of year-after the storms of the winter and before the movement of crops in the summer. For that reason there ought to be seasonal freight rates. This will be agreed to by most coal men if you will ask them, especially those who are connected with large concerns like the Metropolitan Coal Co., and yet they do not get seasonal freight rates partly because the railroads are afraid if they once reduce them they will never have a chance to get them back again. But it would be an improvement to have seasonal freight rates. Another thing: When we are buying in New England we want really a certain amount of heat value in our coal. There is no great advantage in our buying ash, nor is there any particular advantage in the railroad shipping ash and clogging the circulatory system of the body politic any more than clogging the circulatory system of the physical body. It would be desirable if the wholesaler, and to some extent the retailer, could guarantee the amount of ash or sell their coal on heating value. If you are interested in that you will find some interesting charts, in "Anthracite Coal Costs Analyzed," a pamphlet issued by the Anthracite Coal Consumers Association, Inc., New York City, as to rates from various and sundry points for bituminous and anthra-cite coal from the field to New York, Buffalo and Chi-cago. Here in New England they are both up against the competition of oil. About 3 or 3 1/2 bbl. oil will do the work of a ton of coal. One of my millionaire friends who is well posted on the situation is putting oil in his Commonwealth Avenue house because it is the most economical. Moreover, we can get Welsh coal from across the water (and help equalize this matter of exchange with Europe) in close competition with Penn-sylvania coal.

Jan 4, 1928

By Fred C., Bond

DETERMINATIONS of circulating load in a classifier operating in closed circuit with a grinding mill are usually made from screen analyses of the mill feed and classifier products. The percentage remaining on someone selected screen size must be used in the calculation, and, because of the wide variation in average particle size between the mill feed and classifier overflow, an accurate and representative result at the selected mesh is often difficult to obtain. To overcome this difficulty and reduce the time required in making the determination, I have devised a method which uses the liquid-solid relationship in the circuit rather than screen analyses. The quantities required for the calculation include only the usual dilution and feed tonnage measurements, which should be made regularly in the course of ordinary mill operation and, in addition, the amount of new water added to the classifier, or to the head of the mill with the new feed. If measurements are obtained on both of these quantities it is possible to check the calculated circulating load, and to calculate the percentage of moisture in the new feed to the mill; or, if the latter is known, to check the feed tonnage.

Jan 1, 1937

By W. R. Shimer, F. O. Kichline

The investigation herein described was carried out for the purpose of studying, both by chemical and metallographical means, the extent of over-oxidation of steel that can be accomplished by excessive overblowing in a Bessemer converter. 111 addition there are appended some results of basic open-hearth and crucible steels. Remarks on Chemical Methods. The test block used was hemispherical in shape, 4.5 in. in diameter and 2 in. thick. Drillings for analysis were obtained by drilling through the entire solid part of the block, carefully avoiding all cracks and blow-holes and mixing these drillings thoroughly. Drillinga were carefully examined for scale and the finest were gone over with a microscope to be sure all scale from whatever source had been removed. Oxygen was determined by the well-known method of Ledebur, modified according to Cushman,1 with, however, the removal of the preheating tube, which was found unnecessary. This method has been found to give concordant results. Blanks run from 0.0003 to 0.0006 g. Duplicate determinations varied not more than 0.001 to 0.003 per cent. It seems to be generally supposed that the hydrogen method gives only that oxygen which is combined with iron. Whether this be true or not, the content of oxygen existing as iron oxide no doubt predominates sufficiently, so that the result obtained is sufficient to indicate whether the steel is over-oxidized or not. We are well aware that the oxides of manganese and chromium, when existing alone, are not reduced by hydrogen at a red heat. To learn of their action in steel the following work was carried out: A sample of ferro-manganese and of ferro-chrome were each exposed

Jan 1, 1914

By Charles S. Barrett, F. W. Steadman

DEFORMATION bands of surprising regularity are found in large-grained polycrystalline copper after cold-rolling (Fig. I). Individual bands frequently are large enough to permit a determination of their orientation by means of etch pits and an optical goniometer. Measurements have been made on 21 areas in seven different grains, and these, combined with X-ray studies of nine single crystals that had been cold-rolled after mounting in a polycrystal-line block, have contributed to a better understanding of the preferred orientations in rolled copper just as similar studies have for rolled iron' and brass.2.3 Particular attention was given to determining orientations that are stable during rolling and to the manner of fragmentation and rotation of unstable grains. The possible role of twinning was also carefully investigated. The texture of polycrystalline copper after cold-rolling is well established by the pole figures that have been plotted by Schmid and Staffelbach,4 Iweronowa and Schdanow,5 and Brick and Williamson,3 all of which are in substantial agreement. There has been some divergence in the list of individual "ideal" orientations that have been used to describe the texture by these observers and others,6 although the orientation (110) [112]-that is, (110) parallel to the rolling plane and [112] parallel to the rolling direction-is generally recognized as the most prominent orientation and (I12) [111] one of the lesser orientations. Other orientations have been given by some observers as (236) [533], (100) [001], and (I 10) [001]. The texture of copper has also been described as (135) [533].6.1 The sum of these orientations provides a reasonable approximation to the complete pole figure, but it does not follow that these specific orientations are necessarily of fundamental significance, for the choice of indices is arbitrary, within limits. Furthermore, a detailed investigation of the ideal orientations in cold-rolled iron discloses continuous ranges of equally favored positions rather than definite positions of high stability,1 and similarly Brick's observations in a single crystal of a brass2 suggest that all orientations in the range between (110) [113] and (110) [117] are about equally stable. MATERIALS AND METHODS The material used was vacuum-cast electrolytic copper kindly supplied by L. L. Wyman, of the General Electric Co.* Slices 1/2 in. thick and 2 1/2 in. square, cut from the ingot, were rolled with 50 per cent reduction per pass to final thicknesses between 0.02 and 0.04 in., and etched to develop cube-face etch pits suitable for goniometric work.8 The etch was light on some strips and deep in others.

Jan 1, 1942

PRESIDENT AND DIRECTOR SCOTT TURNER WASHINGTON, D. C. PAST PRESIDENTS AND DIRECTORS WILLIAM H. BASSETT WATERBURY, CONN. ROBERT E. TALLY JEROME, ARIZ. TREASURER AND DIRECTOR KARL EILERS NEW YORK, N. Y.

Jan 1, 1932

Jan 1, 1947

By Basil Prescott

A thorough knowledge of the peculiarities of this type of orebody is necessary in sampling these limestone replacement deposits. Oxidized ores are often overestimated because of error in determining specific gravity and actual cross-section of the orebody, and sulfide ores are often underestimated because it is difficult to scatter the samples so that they will accurately represent the area under consideration. This paper describes various methods of sampling and cites factors that enter into the estimation of these deposits. IN THE science of evolution of the species, there is a law which, simply stated, avers that the history of the individual repeats the history of the race. Similarly, if unassisted by the experience of others, each successful engineer would perfect and develop his methods and technique from the rough grab sample up to the carefully taken, recorded and studied samples and observations which now determine and decide the expenditure of the large sums required for modern mining. Hence real progress results from the interchange of experience, as in that way the entire experience of the profession can be made available to every engineer. The literature of this subject is already voluminous, but some progress has been made in the gathering of data and in their compilation or presentation.

Jan 3, 1924

By Joseph Sinclair

THE Republic of Ecuador is situated partly in the northern and partly in the southern hemisphere. The equatorial line passes about 11 miles north of Quito, and. divides the country into two almost equal parts. Crossing the equator almost at right angles, and extending from Colombia into Peru, the Andes form a great upland that, in cross-section, resembles a truncated cone, the top of which is about 40 miles wide and about 10,000 ft. above the sea, while the base is about 80 miles wide extending from sea level, on the Pacific Coast, to the Amazon Plain, on the east. Superimposed on this upland are many active and extinct volcanoes, which form roughly two parallel chains of mountains, on the eastern and western boundaries, respectively, of the plateau. These are often referred to as the Eastern and Western Cordilleras of the Andes, although their parallelism is somewhat. questionable. The highest of these mountain, masses is Chimborazo, about 21,000 ft., above the sea; among the others is the volcanic peak, Cotopaxi, rising to about 18,000 ft. above the sea. The development of the petroleum resources of Ecuador is greatly affected by this Andean mass, not only .because of its composition and geological structure but because of the barrier it interposes between the lowlands on the Pacific side and whatever part of the Amazon Plain to the east is finally found to belong to Ecuador, for the eastern boundary of the Republic is still in dispute with Peru. To understand, therefore, the development of the petroleum reources of the Ecuador and the barriers to such development, we must bear in mind the three great physio-graphic divisions, viz., the Pacific Coastal region on the west, the Andean Plateau in the center, and the Amazon Plain on the east. The first important effect of the threefold physiographic division is that Ecuador has two sets of petroleum regulations: one for. that portion east of the Andes, and one for the Andean Plateau and the Pacific Coastal region although it is probable that the two sets of regulations are, in part, 'due to the boundary dispute with Peru.

Jan 3, 1924