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PRESENTATION of the 1922 Washington Award to Capt. Robert W. Hunt, honorary member and twice president of the Institute, was made at the annual dinner of the Western Society of Engineers, in Chicago, on June 18, 1923, in the presence of 250 mem-bers and guests. W. L. Abbott, Chairman of the Award Commission, when delivering the presentation address, said The life of the Govern-ment of this country, as the lives of governments are usually measured, is short, barely 150 years, but meas-ured by what it has accom-plished, this country has reached a venerable age. The first 75 years of our country's existence were necessarily preparatory to the greater developments which came in the second, and that last half of our country's existence is ex-ceeded, by ten years, by the span of life of our honored guest. "Very little iron and steel were produced in this coun-try until after the birth of Robert W. Hunt. And it was not until after 1860, when as a boy of 21 he joined his fortunes with those of the Cambria Iron Works, that the iron and steel business of the country really took root. After a year or two with the Cambria Works, he left a promising position to go into the army, where he served for four years. After the close of the war he returned to the iron works and qualified himself as a metallurgical chemist.

Jan 7, 1923

By Elmer R. Kaiser

COMBUSTION of coal and transfer of heat from flames and gases to boiler surfaces continue to be of great interest to engineers here and abroad. Numerous investigations have been in progress to improve furnace and boiler performance and economy. The importance of better understanding of the processes and opportunities for improvement is apparent when it is remembered that heat from at least 500 million tons of coal a year the world over is being transferred to boiler water at efficiencies ranging mostly between 50 and 90 pct. Even slight gains in efficiency, economy, and labor saving become very significant when multiplied by the enormous quantity of fuel consumed. Also the competitive position of the large coal, oil, and gas industries in satisfying the fuel consumers is greatly affected by the achievements made through technical progress with each fuel. This paper is part of a continuing activity of Bituminous Coal Research, Inc., to extend the knowledge of coal utilization for steam generation and to seek promising directions for future research and development in cooperation with others. Particularly in the latter regard, numerous interviews were held during the last three years to seek the experience and advice of boiler and combustion- equipment manufacturers, electric-utility executives, and fuel engineers. A wealth of published information was also reviewed, which together with the interviews pointed to the advisability of further work on ash and sulphur control.

Jan 3, 1954

By Robert L. Greyer, John I. Myung

The Birdwell 3-D Velocity Log displays photographically the amplitude of elastic waves as a function of time and of the depth of the logging tool in a borehole. The elastic waves are generated by a magneto-strictive source transducer and detected by a receiving transducer, which is at a fixed distance from the source. The output of the receiver, which is proportional to the amplitude of the received elastic waves, modulates the light that exposes the film record. The duration of the receiving time can be selected to record the entire wavetrain of late events or to record only early events at a finer time scale. When a full complement of elastic waves (i.e., the refracted compressional wave, composite shear wave, direct fluid wave, and boundary wave) is recorded, their velocities and the density of the borehole fluid provide the information necessary to compute the elastic moduli and density of the rock surrounding the bore-hole. The differences between the values of the moduli determined from measurements of 3-D Velocity Logs and by other better known techniques are small, well within the limits of experimental error, when the velocity log is interpreted by an experienced seismic analyst. INTRODUCTION Quantitative descriptions of the mechanical properties of the rock environment have long been basic requirements of planning, design, and quality control of engineering projects. Because of this need, many techniques for determining the elastic moduli from static and

Jan 1, 1971

By R. H. Atkinson

With the object of improving the melting, casting, and working of palladium and 95.5 pct Pd-4.5 pct Ru, the effects of different melting atmospheres (reducing, oxidizing, and neutral), crucible linings, and annealing atmospheres have been studied. Some interesting observations are included about the solubility and diffusion of gases in palladium. THE object of the present work was to ascertain the effect of oxidizing, inert, and reducing ambient atmospheres on the melting and casting of palladium and a Pd-Ru alloy commonly used for jewelry. The need for such a study was indicated during World War I1 when jewelers experienced difficulty in their attempts to make small castings of the torch-melted Pd-Ru alloy by the lost-wax process. When the metal was melted under oxidizing conditions similar to those used for platinum, the castings were gassy; on the other hand, if the melting atmosphere was reducing, the castings were hot-torn and brittle. General Experimental Procedure Pure palladium sponge (99.9 pct Pd) and pure ruthenium powder (99.8 pct Ru) were used for making small ingots (50 g) of palladium and 95.5 pct Pd-4.5 pct Ru by induction melting. The coil, 3 in. high by 2 in. ID with 16 turns, was energized by a 20 kva Ajax high frequency converter. The melting crucibles, so-called sand crucibles, which were made of a highly refractory fireclay, were lined with different materials, including proprietary magnesia, alundum, zircon, and zirconia

Jan 1, 1957

By John V. Beall

Tsumeb has added a chapter to its absorbing history with the beginning of copper smelting operations this month. This development will be followed shortly by another one when lead smelting and refining plants go on the line next year. In our own milieu these events would be common- place enough (although a new lead smelter certainly would be cause for wonder), but in the sparsely settled remote regions of northern South West Africa they are a dramatic industrial expansion. They are also, however, a sound businesslike extension of policies which have marked the tenure of Tsumeb Corp. Ltd. The historical data given in Table I are a drab listing of factual bones without the corporeal splendor which should surround the denouement of the Tsumeb bonanza. When Sir Francis Galton traversed the country, his was an expedition which was in keeping with the then blooming era of heroic explorations. The Otavi highlands in the interior were unexplored and the reception of the natives uncertain. While the exploratory work was in progress during the turn of the century the Hottentots and Hereros were successively in open bloody rebellion. The suppression of these uprisings, particularly the Hereros, by German soldiers so decimated the tribes that a labor shortage ensued for many years, hampering the development of the colony. To these troubles may be added difficulties In obtaining mining supplies. However, there should have been no shortage of meat from wild game judging by conditions prevailing even today.

Jan 12, 1962

By N. B. Gray, R. V. Culver, W. S. Boundy, N. W. Stump

The kinetics of sulfation of single crystals of lead sulfide to lead sulfate have been studied between 969" and 1073°K in gas atmospheres of known composition using a thermobalance technique. The data are described by an equation derived on the basis that diffusion outward through the Product layer is the major controlling step. The rate of sulfation is linearly related to the logarithm of the sulfur trioxide partial DESPITE its industrial significance the oxidation of lead sulfide has received limited attention. The oxidation reactions have been studied using beds, briquettes, single crystals, or thin films of lead sulfide. Lead oxide and lead sulfate (PbSO,) were formed when Mclntoshl and Gardner2 roasted beds of galena pressure and the temperature coefficient of reaction is 40 ± 5 kcal per g mole. Gold marker experiments show that the sulfate layer grows by outward movement of ions through the sulfate layer. Initially the PbSO, adheres to the PbS but later forms an irnpewious spheroidal envelope; PbS vaporizes and pb2' ions diffuse through the envelope to react at the external surface. in air at temperatures up to 800°C. In a more extensive investigation, Tchizhykov3 obtained Pb, PbO, and PbS04 in accordance with Eqs. [1] to [4], when a bed of -200 mesh galena was oxidized in O2-N2 mixtures at 700° to 900°C.

Jan 1, 1968

By J. J. Demo

The effect of aluminum additions on the coating vale and corrosion resistance of Cr-Fe diffusiou coalings on a mild steel substvate has been studied. Aluminum additions up to 2 wt pct increase the chromium penetration rate while further additions retard it. The apparent cor$lict between these data and metallogyapkic ineasurements, which show a continuially increasing coaling thickness with aluminum addition, is discrissed. Compavisorz of corrosion resistance on the basis of equal thickness of tlre entire coating measured mnetal- ALTHOUGH ferrous metal articles are cheap and widely used, they are often quickly degraded by corrosion. To prevent or slow down the corrosion process, lographically is misleading; equal thickness of the cor-rosion-resistant portion of the coating is a bette.v basis of conzpavison. Inter difision coefFicients for Cr-Al-Fe coatings of different aluminum content have been detevmined and found to dary logarithmically when plotted againnst chromium concentvation. A general method of calculating diffusion profiles for different lrealment limes and surfuce coucentralions IS described. many types of coating are applied to steel.' Among these are diffusion coatings, formed by high-temperature diffusion of selected elements into the surface, which then becomes the coating Diffusion coatings are metallurgically bonded to the substrate and show a continuously varying concentration gradient from surface to substrate. Generally, these coatings have the advantage of adhering to the substrate upon deformation of the composite. Moreover, when chromium is one of the diffusion elements, a mild steel substrate

Jan 1, 1968

By Charles Maier

IT has long been supposed that when crystalline materials are com-minuted the energy used in the production of increasingly smaller grain sizes is not entirely dissipated as heat but that a certain portion is "stored" as a part of the internal energy of the material. This portion usually has been called the "surface energy" of the particles. The practical interest of the Bureau of Mines in this subject in connection with the energy requirements of crushing processes has led to the author's attempt to measure the "stored" energy in finely divided calcite by heat-of-solution methods1. The experiments on calcite showed that "storage" of energy could not be proved for this material, because fine grinding caused a lack of chem-ical homogeneity evidenced by loss of carbon dioxide and subsequent adsorption of water on the surfaces of the calcite particles. When thermochemical correction was made for composition changes the cor-rected heat of solution was less for fine material than for coarse. Con-tinuation of the experimental work into the problem of comparing work and heat in the deformation of metallic crystals, where the calorimetric difficulties were less, showed, however, that in the case of copper and aluminum a real discrepancy between work and heat could be shown. similar results had previously been obtained by Farren and Taylor2 and Hort3 and more or less simultaneously with the author's work by

Jan 1, 1936

By L. B. Underwood, C. J. Distefano

NORAD, when completed, will be housed in large chambers excavated out of the granite beneath the Cheyenne Mountain near Colorado Springs. A room and pillar layout for the chamber excavation was selected and executed. Many complex problems arose in designing a rock bolt system; this paper includes discussions on: rock strengthening following excavation, excavation and ground support problems, orienting rock bolts with respect to jointing systems, conducting pull tests, four-way chamber intersection problems, the need for grouting rock bolts, and loss of tension and permanency of anchorage in a rock bolt system. In the event of a sudden nuclear attack upon the United States, it is imperative that vital command and control centers have a high probability of survival. One such vital facility is the North American Air Defense Command Combat Operations Center at Colorado Springs, Colo. Known briefly as NORAD, this installation when completed will be housed in large chambers excavated out of granite beneath the eastern slope of Cheyenne Mountain (Fig. 1). The NORAD COC, a U.S. Air Force sponsored project, will serve as the primary collection and evaluation center for data concerning unknown aircraft, missiles, or space vehicles, which might bring destruction to North America. The data will be fed into high-speed computers and electronic equipment from outpost sources: radar, ballistic missile early warning stations and picket ships throughout the world. Electronically controlled display boards will make it possible to evaluate the tracking data instantaneously and to take appropriate defensive action.'

Jan 1, 1968

By J. L. O’Brien, M. Suenaga, K. M. Ralls, V. F. Zackay

The effecls of aging a1 400°C on tile resistive transition at 4.2°K of a superconducling 70Zr-30Nb alloy are reporled. Microstrclural changes were studied by critical temperature, resistiue critical field, residual resistiuily, and microhardness measurements and by X-ray diffraction, optical microscoby, ad replication electron microscopy. The result of the aging treat- A defect-free Type 11 superconductor in a magnetic field above Hc1 cannot sustain a transport current runt is a fine array of w-phase pavticles with a mean center to center interparticle spacing of about 800A. At an aging time of 300 hr the maximum onset critical current density is rcached. The particle size at the maximum current density if about 4202. At times longer than 300 hr effective particle impingement leads to lower onset critical current densities. perpendicular to the applied field without power loss in the sample.'-3 This power loss is due to flux line motion caused by the Lorentz force and is manifested by a longitudinal voltage.4-6 When defects are present in the material, flux lines are pinned until the Lorentz force exceeds the "pinning force". That is, it is thought that flux lines reside in free-energy wells existing at the defects, and the critical Lorentz force is that which when integrated over distance will supply the free-energy difference necessary to move the flux

Jan 1, 1968

By Paul Sterling

The general impression regarding the preparation of merchantable anthracite is that it is confined to a colossal, grimy structure, called a " coal-breaker." This name is a misnomer; for the desired result is not to break the coal, but to prevent its being broken. Preparation may be said to begin at the face of the chamber, with the mining and loading of the coal. Local conditions vary, not only ill the same field or basin, but also in the same mine, so that there is no fixed empirical rule governing the method of blasting or cutting coal. Tests should be made, when possible, to determine the explosive, or the mechanical coal-cutter, which will produce the largest percentage of what are locally known as " lump " and " prepared sizes " of anthracite. The prepared sizes are those mostly consumed for clomestic purposes. All other sizes might be called by-products of the anthracite industry; for they are not especially desirable, being the degradation resulting from the mining and handling of a brittle or laminated material. Being low in volatile combustible matter, anthracite burns most successfully when nearly of a uniform size, permitting the easy passage of air through the voids. This accounts for the large number of sizes into which the coal is separated. Table I. gives the various sizes, the diameter of ring over and through which each size is made, and the usual purpose for which it is employed.

Jan 1, 1912

By Charles Maier

PART I DENSITY AND ENERGY CHANGES IN COLD-WORKED COPPER IT has long been supposed that when crystalline materials are com-minuted the energy used in the production of increasingly smaller grain sizes is not entirely dissipated as heat but that a certain portion is "stored" as a part of the internal energy of the material. This portion usually has been called the "surface energy" of the particles. The practical interest of the Bureau of Mines in this subject in connection with the energy requirements of crushing processes has led' to the author's attempt to measure the "stored" energy in finely divided calcite by heat-of-solution methods1. The experiments on calcite showed that "storage" of energy could not be proved for this material, because fine grinding caused a lack of chem-ical homogeneity evidenced by loss of carbon dioxide and subsequent adsorption of water on the surfaces of the calcite particles. When thermochemical correction was made for composition changes the cor-rected heat of solution was less for fine material than for coarse. Con-tinuation of the experimental work into the problem of comparing work and heat in the deformation of metallic crystals, where the calorimetric difficulties were less, showed, however, that in the case of copper and aluminum a real discrepancy between work and heat could be shown. Similar results had previously been obtained by Farren and Taylor2 and Hort3 and more or less simultaneously with the author's work by

Jan 1, 1936

By J. L. Bray

IT is well known that iron markedly improves the physical properties and casting characteristics of aluminum bronzes. The use of 1 to 4 per cent iron as the principal modifying addition has become common practice in many foundries melting aluminum bronzes. Although the beneficial effects of iron are unquestioned, there is some uncertainty regarding the structural changes caused by it in the basic copper-alumi-num system. It is agreed that a new constituent appears in abundance when the iron content reaches 2 to 4 per cent. This constituent, which frequently occurs in shapes resembling clover leaves, is sometimes assumed to be an aluminum-iron intermetallic compound. If this were correct we might expect a change in the structural relationships of the matrix in the direction of decreased aluminum content. On the other hand, it has been reported that iron has a negligible effect in altering the fundamental relationships of copper-aluminum alloys1. Others2,3 have reported an additive coefficient. Apparently it will be necessary to know the equilibrium relationships between the phases of the copper-aluminum-iron alloy system to establish any such theory as fact. When this has been done it may very well be that a further revision in the structural relationships may be necessary to describe the changes to be expected in commercial cast alloys. It was with this latter problem before them that the authors attempted to

Jan 1, 1936

By Augustus Locke

In 1900, when. the public first heard of "secondary enrichment," the Butte chalcocite seemed clearly supergene. Mining, through successive regions of leached capping, bonanza sulfide, and sulfide less rich, had paused at lean bottom levels which, though chalcocite-bearing, suggested the waning of copper. The deepest chalcocite, at 1500 ft., was yet too shallow to disturb the supergene hypothesis. But, with deeper mining, lean levels yielded to fat ones. Here and there they showed, within the same vein, an inverted distribution, chalcopyrite above and chalcocite below. To the miners' astonishment, they carried chal-cocite, unaffected by cross faults, on an independent course to the depth of 2500 ft. The pattern of ore distribution, hitherto revealed only in fragments, was now appearing in perspective, and, in the depth of the chalcocite, was beginning to make Butte differ from all districts where the chalcocite is indubitably supergene. The idea of hypogene origin at length came into favor; by 1913, when Sales' advocated this origin, the argument had become a powerful one. This argument rested on field evidence; but, already, there was beginning to emerge microscopic evidence not included in this argument. Especially pertinent was the proof that (1) the deep chalcocite lies in-mixed with bornite, often microscopic; (2) the deep chalcocite often replaces bornite; and (3) replacement of bornite by chalcocite is accomplished more easily than that of pyrite, enargite, or chalcopyrite. The microscopic evidence has been accumulating for ten years and it demands

Jan 1, 1924

By Charles H. Jacoby

The solution mining of evaporites has a history of approximately 5,000 years. The insitu leaching of metalliferous ore will have many of the same characteristic problems which have confronted industry for years in the production of evaporite minerals. Basically we will be converting the less soluble forms of valuable metals into their more soluble salts and producing these in much the same manner as, for example, sodium chloride. There are a number of problems which we are faced with that are more complex and complicated and, therefore, will require a higher degree of sophistication than previously employed. One of our most important undertakings will be the clearcut definition of the problems involved. While a great deal of expertise can be drawn from the solution mining of evaporites and the oil industry, problems peculiar to the hydrometallurgical field will need to be solved. One of these is the introduction of permeability into an impermeable rock so as to expose the sought after values of metals which by volume are infinitesimal when compared with sodium chloride, potash or other type water soluble mineralization. After establishing this permeability which will be miniscule when compared to a solution cavity, there will be the maintenance of this permeability. In general, salt deposits are of a somewhat uniform chemical composition and thus their chemistry was relatively simple. Each metalliferous ore body is somewhat unique in its chemistry and will need to be treated accordingly.

Jan 1, 1974

By Charles G. Maier

SCIENCE beginning in rational observation came of age, when its devotees first began to measure and count. It has been said that the most striking aspect, of science today is its growing abstraction, and its preoccupation with mathematical symbolism. Technology with specific and concrete objectives in the satisfaction of human wants, cannot conceivably achieve the abstract unification that science seeks, but .the utility of the' scientist's method has been too well proved to require bolstering. Metallurgy is in its scientific infancy.

Jan 1, 1931

By Philip D. Wilson

WHEN the United Nations win the war and the decision has been made to control future armament in the Axis countries, plans for the extent and operation of such control must have been prepared, to be ready to put into immediate execution. Such control to be effective must be premised upon complete military occupation of the two countries for a substantial period, with an arrangement at the end of such occupation for continued supervision of these industries into an indefinite future.

Jan 1, 1944

By John V. Beall

WHEN asked a few weeks ago if we wished to visit the Coors plant at Golden, Colo., we agreed with alacrity being well acquainted with the high quality of Coors beer and having heard that the company was most liberal about sampling privileges. Instead of a brewery, we found ourselves in a pottery, the Coors Porcelain Co., owned and operated by the firm of beer fame. Our apparent disappointment was dispelled as the wonders of the porcelain products were unfolded.

Jan 2, 1953

By J. A. Gay

BRITISH success in extracting significant quantities of germanium from gas works flue dusts has been one of the prime forces in promoting similar research in the United States. Pittsburgh Consolidation Coal Co. and Pennsylvania Coal & Coke Co. are two of the larger U. S. firms with germanium from flue dust research programs. British interest in germanium started in 1933 when V. M. Goldschmidt reported that some coals from the Yard Seam of Northumberland and Durham contained 30 to 50 ppm of germanium.

Jan 8, 1953

By James Douglas

As the operation of light railroads is important to the mining industry, the following statistics of the Arizona Southeastern Railroad may be of interest. When the traffic of the Bisbee copper-mines reached 20,000 tons per year the necessity of better transportation than that afforded by eighteen- and twenty-horse and mule teams became imperative on the score of both cheapness and convenience. Before deciding on the construction of a railroad, the Copper Queen Company made a thorough experiment in transportation

Jan 1, 1899