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By D. J. Jr. McAdam

RESULTS of a general survey of corrosion-fatigue phenomena at the Naval Engineering Experiment Station were presented in five previous papers.1-5 In these papers references were given to the work of Haigh in 1917.6 The five papers mentioned gave a general survey of the behavior of metals when tested to failure under simultaneous corrosion and cyclic stress. As a result of this survey the fourth paper gave a tentative analysis of the corrosion-fatigue process. According to this analysis, if the initial stress is below the endurance limit but above the corrosion-fatigue limit, the corrosion-fatigue process is divided into two periods. The first period is the formation of pits. As the initial stress is below the endurance limit, the pitting is assumed to be due to corrosion, not to fatigue. The corrosion pitting, however, is not the ordinary pitting of stressless corrosion, but is an accelerated pitting due to the effect of the cyclic stress on the corrosion. As the pit progresses, both the actual stress and the effective solution pressure increase. The increase of actual stress is due to increasing stress concentration at the bottoms of the pits. The increase of effective solution pressure is due to the increase of actual stress. The mutual intensification of stress and solution pressure continues until the actual stress at the bottoms of the pits surpasses the endurance limit. The second period of corrosion-fatigue then begins. In this period the process is merely fatigue accelerated by the corrosion. The cracks advance at a continually accelerated rate until the specimen breaks.

Jan 1, 1930

By J. H. Nead

OBJECT THE experiments herein described were undertaken with a view to investigating thoroughly the influence of carbon on the tensile and impact physical properties of carbon steel. The original comprehensive plan included investigation of a series of steels with varying carbon contents over a wide range of heat treatments. These were to be studied as to their static tensile qualities, and also their resistance to shock as measured by the Charpy impact bending test. A thorough metallographic examination was likewise included in the schedule. The Charpy tests and the metallographic examination have not been completed to date, and are accordingly withheld for another report. All heat treatments, however, have been made, and the static tensile tests have been completed. A description of the procedure of the experiment and the results thus far obtained are therefore reported herein. CONCLUSIONS No attempt is made to draw general conclusions from these experiments, but the curves and the data are submitted as being of general importance and wide applicability.

Jan 12, 1915

By D. Bergekoff

IN the routine examination of a wide variety of metal specimens it is sometimes necessary to have special methods of polishing in order to retain and reveal certain details in each specimen. Among such special cases is the retention of graphite in malleable and gray cast irons, the preservation of all types of nonmetallic inclusions in both hard and soft steels, obtaining a scratch-free surface with soft metals, and avoiding the usual relief effects with very hard specimens such as tool metals con-taining various carbide and nitride phases. It is the purpose of this paper to give an account of some of these special polishing methods in use at the Union Carbide and Carbon Research Laboratories. The polishing procedures outlined have been found to give uniform results. It is obvious that only general rules and the most important working details can be given here. Following these rules, the polisher can obtain satisfactory results if he possesses the necessary patience and has a sincere desire to give as nearly perfect a finish as possible to his work.

Jan 1, 1939

By W. H. Bassett, J. C. Bradley

Beads of metal frequently appear at the ends of cast-copper wire bars and on the sides of wedge cakes near the top. These are richer in cuprous-oxide than the rest of the casting. A micrographical study of these exudations has been made. 11 is suggested that the materical is forced through the surface while the copper is solidifying. If not eliminated in process of manufacture, it shows on the finished polished sheet copper in patches differing in color from the main body of the shad. Figures 1 to 4 show the copper exudations, at different magnifications, as they appear on the ends of cast wire bars, and on the sides, usually near the top, of wedge cakes. Sometimes the exudations are in fine "drops;" at other times, large masses of the material are found. Microscopic examination of the copper exudation indicates that it is high in oxide and of eutectic proportions. Because of the difficulty of securing a suitable sample, the protuberances have not been analyzed chemically; but the spectroscope shows no indication that there are any more metallic impurities present than in the balance of the copper. The lowest copper plus silver content of the coppers studied for this paper was 99.914 per cent.; the highest, 99.966 per cent.; so the oxygen content of the whole casting would be well under 0.07 per cent. Structure of Protuberances The segregation of oxide between grains in the interior of the cast bar, not far from the "set," is shown in Figs. 5 and 6. In general, the amount of cuprous oxide begins to increase at a point about 0.01 in. below the normal surface of the casting, i. e., the base of the drop; but it does not attain maximum concentration in the main body of the metal. Vertical sections, Figs. 7 to 12, show that there is a definite line of large cuprous-oxide globules at the base of the drops. Horizontal sections at this place show that these large globules lie in a thin billowy

Jan 1, 1926

Jan 1, 1923

By Richard H. Rein, John Chipman

Liquid slags of the system SiO2-Ca0-MgO-A1~03 were equilibrated with liquid Fe-Si-C alloys in graphite or Sic crucibles at 1600°C in pure CO gas at atmospheric pressure, and the silicon content of both phases determined. Ternary slugs of the systern SiO2-CaO-A12O3 were also studied at 1550°C. The silicon content of the metal phase saturated with both graphite and SIC is 22.0pct at 1550°C and In the iron blast furnace, as in nearly all carbon-reduction processes, some silicon is transferred from slag to metal. The importance of this reaction is enhanced by its indirect effect on the transfer of sulfur from metal to slag, and this has stimulated a comprehensive research program on the equilibrium distribution of silicon between slag and metal. Earlier studies'-3 of this same problem provided data for calculation of the thermodynamic activities4 of the components in SiO,-CaO-A1,O3 slags. 22.4 pct at 1600°C. The temperature at which the phases cristobalite, gvaphite, $ SiC, liquid slag, Fe-Si-C alloy, and CO gas at 1 atm pressure can coexist in equilibrium was found to be 1533°C. The results agree well with earlier studies. They are shown graphically as lines of constant silicon cmtent in the metal which also are lines of constant SiO, activity in the slag.

Jan 1, 1963

By AIME AIME

The following financial report of the Treasurer of the United Engineering Society is published for the information of members NEW YORK, February 15, 190S. To the Board of' Trustees, United Engineering Society I beg to submit herewith the report of the Treasurer as of December 31, 1907. Your attention is called to the fact that the resources and liabilities, receipts and disbursements statements cover all the financial transactions of the United Engineering Society from its organization up to December 31, 1907. The income and expenses of operating the building during the whole operating period from December 1 to December 31, 1907, somewhat in excess of twelve months, are given. Included in the expenses, amounting in all to $52,647.11, will be found an item entitled "Building Equipment (construction account)." The expenditures under this item were not made for the operating expenses of the building, they represent a construction account, properly speaking, covering expenditures for furnishings and equipment of the building. The Founders' Agreement specifically provides for this class of expenditure under the provision that the Founder Societies shall each be liable for a charge not to exceed $200,000 of principal, which shall include the land and building completed and ready for occupancy, together with the " furnishings, equipment and personal property therein." Certain details of equipment are yet to be supplied, and it. is proposed in the near future to call upon the Founder Societies for an assessment on their respective land and building funds to cover this item of building equipment. Such action would enable the item of $10,039.85 to be transferred to the income account and reduce correspondingly the assessment

Mar 1, 1908

By Dennis V. D’Andrea, Sidney M. Runke

This paper describes the Bureau of Mines-El Paso Mining and Milling Company cooperative research program at the Emerald Isle mine3 near Kingman, Ariz. This research program was directed toward developing in situ leaching methods for 200,000 tons of ore exposed in the pit bottom and also 1,500,000 tons of ore under 200 feet of overburden adjacent to the pit. A test area in the pit bottom containing 15,000 tons of ore was blasted and leached. The results of this leach test were encouraging, and the entire pit bottom was leached in-place for about 7 months. Two test blasts under 200 feet of overburden and extending to 290 feet were detonated in an area near the open pit. The results of these blasts were evaluated by core drilling and permeability measurements. An in situ leaching system was designed, but not implemented, to recover copper from the 1,500,000-ton area near the pit. The company decided to terminate operations at the Emerald Isle mine in November 1975.

Jan 1, 1976

By J. L. Bray

LEAD has often been suggested as a protective coating for iron and steel. Such a protective coating should possess: (1) good adhesion, (2) durability, (3) ease of application, (4) freedom from pinholes, (5) good appearance and (6) low cost, but, unfortunately, lead coatings so far produced do not have all of these characteristics. Because of the necessity of carrying out the coating process cheaply, and because lead solutions have poor plating characteristics, most of the efforts have been directed toward the hot-dipping process rather than electroplating. The hot-clipping processes using lead have not been successful chiefly because of the lack of adherence between iron and lead. In any coating process involving iron a bond can be obtained only by the formation of an intermetallic compound, the formation of a solid solution, or mechanical means. Lead forms with iron two immiscible liquid solu-tions, and in the solid state no intermetallic compounds or solutions. It is necessary, therefore, to employ some other element or elements as a binding agent. Tin may be used as in terneplate, or copper in the form of a thin film of electrolytically deposited metal to which the lead will adhere. Because of its physical and chemical properties, lead as a coating medium would undoubtedly be limited in its use to sheet and wire and then only when the article is not subject to abrasion or wear. A very large tonnage of these products are being used under such conditions and a successful lead-coating process should be a valuable contribution to the science. Two other difficulties stand in the way of successful lead coating-that of poor appearance of the weathered surface and the tendency of the lead to form pinholes during solidification. Since lead is commonly accepted as cathodic to iron, these exposed areas are ones of accelerated corrosion.

Jan 1, 1937

By John Griffen

THEORY HYDRAULIC classification as explained by Rittinger and others was largely restricted to conditions wherein the free-falling velocities of the particles were conceived as governing the separations effected (see chapter 9). The laws governing classification under free-falling conditions have been summarized by Chapman and Mott as fo1lows:l Nomenclature r represents, in a particle of irregular shape, the round-hole screen through which the particle would pass, or some other linear dimension of the particle equivalent to d, the diameter of a sphere. s, the specific gravity of the particle. 1, the specific gravity of the water used as a medium. K, a constant. W, the velocity of the water. In an Upward Current of water 1. A particle will move upward if [V > K dr(s - 1)] and, by suit- ably regulating the speed of the water current, the larger and heavier particles may be made to fall downward against the current, leaving the smaller, lighter particles in suspension in the current. 2. Particles such that [- = -] cannot be separated in an upward- current classifier with any one velocity of current. Coal particles having a specific gravity of 1.35 cannot be separated from refuse particles of [2.5 - 1 2.5 sp. gr.] unless the ratio of diameters is less than [ 4.3 to 1, 1.35 – 1] and the raw coal must be screened to size limits within this ratio if they are to be separated. Cone-shaped vessels or vessels of other shapes that allow the use of different velocities of current at different points in the flow are used to modify this limitation.

Jan 1, 1943

A. Blainey (Ministry of Supply, Atomic Energy Research Establishment. Hnrtoell. England)—With ref- erence to the published work of Hausner et al. on the powder metallurgy of zirconium, it will be of interest to summarize briefly the results of preliminary work we have carried out on this subject at A.E.R.E., Harwell. For the early experiments we used zirconium

Jan 1, 1953

By N. F. Dyson, T. R. Scott, M. R. Thornber, W. E. Ewers, M. Bussell

Leach liquors derived from the processing of nickel ores are generally highly contaminated and contain appreciable free acid. Methods are described for obtaining a commercial grade of concentrate from such solutions using pyrrhotite as the seed material to abstract nick- el, cobalt, etc. from solution. At temperatures in excess of 160° C., recoveries of 99% can be obtained from contaminated solutions where the free acidity is as high as 0.5 M in sulphuric acid. At lower temperatures down to 80° C., high recoveries can also be obtained either by adding H2S to the system with appropriate adjustment of the free acidity or by using "activated" pyrrhotite or artificial FeS in the system without prior addition of H2S. The methods are applicable to liquors derived from either oxide or sulphide ores, and the products are suitable for smelting or other known processes used to obtain pure metals. The mechanism of the reaction appears to vary with the operating temperature, and the results ye therefore discussed in the light of electron probe and optical microscopic studies.

Jan 1, 1973

By Sandip K. Mitra, John E. Dorn

The Basinki-modified Seeger equation for deformation of metals by means of thermally activated intersection of dislocations was used to ascertain the various factors responsible for the strain hardening of poly crystalline aluminum and a series of a solid solutions of magnesium in aluminum. The analyses were based principally on the rate of change of strain rate with stress and the Cottrell-Stokes ratio. From measurements of these quantities on a series of strain-hardened states, the force displacement diagram for intersection, the density of dislocations in the entanglements, and the contributions of the athermal local stress and long-range stress interactions were deduced. Poly crystalline aluminum was observed to have the same force-displacement diagram for intersection as single aluminum crystals, and the corresponding diagram for the magnesium alloys differed in a manner that suggested that small amounts of magnesium may decrease slightly the stacking fault energy of aluminum. Although poly crystalline aluminum had about the same initial density of dislocations as the single crystals, the density of dislocations increased much more rapidly with strain in the polycrystals. This factor and the higher back stresses generated in the poly crystalline aluminum were the major factors responsible for the higher strength of the poly crystalline aluminum, As the magnesium content of the alloys was increased, the initial density of the dislocations also increased. Most of the alloy strengthening arose from this factor; alloying effects due to short-range order strengthening, Suzuki locking, Cottrell pinning, and so forth, were estimated to be quite small. The gveater rate of strain hardening in the alloys was deduced to be due primarily to the greater increase in the density of the dislocations with strain as the magnesium content was increased. It is the purpose of the present investigation to shed additional light on the average plastic behavior of a grain in a polycrystalline aggregate, by analyses, based on dislocation theory, of appropriate experimental test results. These deductions when compared with those from single-crystal data will then serve to illustrate the major items of difference between the plastic behavior of single crystals and the average behavior of a grain in a

Jan 1, 1963

By A. F. Melcher

The present paper is a progress report on an investigation of the physical factors of oil and gas and especially of their sands,' such as pore space, size of pores or permeability, retentivity, viscosity of the oil, temperature, pressure, thickness and area of the pay sand, water relations, and capillarity. The purpose is to determine as many of these physical factors as possible, and to ascertain the relations existing, directly or indirectly, between these physical factors and the production of oil and gas. As yet only pore space2 and size of grains of pay sands have been investigated, although an apparatus has been designed to determine the permeability of a sand to oil, water, or gas under definite drops of pressure between the entrance face and exit face of the sample. Messrs. E. W. Shaw, R. Van A. Mills, D. Dale Condit, G. B. Richardson, G. C. Matson, and C. H. Wegemann collected the samples upon which the physical determinations were made. Acknowledgment is made to my colleagues of the United States Geological Survey for many suggestions and criticisms; to Mr. Mills for the production data given of the oil wells from which some of the samples were collected; to Mr. A. W. McCoy of the Empire Gas and Fuel Co., Bartlesville, Okla., for many ideas. Determining Pore Space of Oil and Gas Sands In selecting a method for the determination of pore space, two objects were kept in mind: First, the method must not only be sufficiently

Jan 1, 1921

By E. S. Hutchinson

The subject of the influence of coal-dust in mine-explosions has received considerable attention both in England and on the continent of Europe, but until the recent disaster at Pocahontas, Va., it seems not to have been of special interest to engineers in this country. The reason, perhaps, is that most of our bituminous mines are worked by short shafts, slopes and drifts; few have been specially dry; and the explosions that have occurred could readily be traced to fire-damp with 110 complicated circumstances. The object of the present paper is to bring together, for the convenience of members of the Institute, the principal English opinions upon this important subject. Messrs. Lyell and Faraday, in their report to the Home Secretary," in England, on the Haswell Colliery explosion in 1844, seem to have been the first to point out that dust fed the flame originating in a

Jan 1, 1885

A-Metal Mining B-Minerals Beneficiation F-Coal H-Industrial Minerals

Jan 11, 1950

R. B. BRINSMADE, Ixmiquilpan, Hgo, Mexico* (written discussion). As the discussion of Mr. Graton's paper by Messrs. Norris, Patterson, and Crane has been from the standpoint of the mineral land-value owners, a few remarks in the interest of the "under dog"-the average taxpayer and citizen-may prove timely. In my discussion of Doctor Raymond's Paper1 and of the papers of Messrs. Gibson2 and Godson, 3 have endeavored to demonstrate, from both political economy and history, that our existing system of unrestricted private ownership of land is incompatible with equality of economic opportunity and, therefore, subversive of our democratic political institutions. In Mr. Graton's paper, the same land problem is important, though camouflaged by the failure of the Federal income tax laws to distinguish between land and capital, in the requirements for valuation, or between earned and unearned incomes in the levying of taxes. I disagree with Mr. Graton's statement, on p. 2967, as follows: The immense majority of mining ventures are failures. A multitude of disappointments is relieved by occasional success. Were it not for the chance of great rewards, all the vitally necessary but mainly unremunerative work of exploration would not be undertaken. In contrast with nearly all other fields of endeavor, it is altogether unlikely that, on the whole, the gains in the successful mining ventures suffice to offset the losses in the unsuccessful.

Jan 3, 1920

By James F. Kemp

In earlier gears, the custom prevailed of regarding the anthracite basins as cases of folding with slight development of faulting. Folding is so pronounced and, in the eastern and western Middle Fields, at times so violent, that the inference was a natural one and led to the widespread impression that practically all the disturbances of the seams could be explained in this way. The cross-sections and maps prepared forty or more years ago for the Second Geological Survey of P ennsylvania, by Mr. Ashburner under Prof. J. P. Lesley, exhibit little else than folds.' So far as I can discover faults fail in the charts, except in one small case in the Henry colliery near Plainsville on the outskirts of Wilkes-Barre. Some years ago, while spending a day or two in Wilkes-Barr, under the guidance of R. V. Norris, I looked over some recent and accurate cross-sections of a numbcr of the large collieries and was deeply impressed with the peculiar behavior of some of the seams and the intervening shales. Thus, a seam might present a small, more or less overturned fold, rising 30 to 50 ft. (9 to 15m.) above its general course, and yet the movement would be taken up in the overlying shales, so as hardly to be noticeable in the seams next above or below. These and similar anomalies, especially when shown with the accuracy of engineer's surveys, possess great scientific and practical interest, bearing as they do, not alone on coal mining, but on theoretical geology and the actual behavior of strata under great compressive stresses. In preparation for the semicentennial meeting of the Institute, an effort was therefore made to secure some of the most interesting sections for presentation to the members. The collection of illustrations here shown is mainly due to Douglas Bunting of the local committee, to whom and to the contributing companies acknowledgments are due. The illustrations are taken from all four of the main basins, but are chiefly from the portions nearest Wilkes-Barre. The first are in the

Jan 1, 1922

By O. B. Bucklen, P. G. Meikle

INTRODUCTION The trend in the coal industry for many years has been to make every- thing "bigger and faster." This also held true for loading and storage facilities. Where once a million ton per year mine was rare, three to five million ton per year mines are not uncommon today in the bituminous industry. This greatly increased production, made possible through mechanization, required greatly improved loading facilities just to get the coal away from the mine. Also, there is a trend toward combining production from more than one mine and cleaning it in a single preparation plant. In addition to increased loading capacity, this frequently necessitates raw coal storage and blending facilities. The development of the unit train with its attendant economics, more than any other factor, has contributed to the widespread construction of storage and high-speed loading facilities. In the export market, the construction of ever larger coal colliers has contributed to a need for faster and larger loading facilities. In this climate of rapidly changing technology, any written account is faced with the possibility of obsolescence before its appearance. Thus, this chapter seeks to define the common and current practice in coal loading and storage facilities with the full knowledge that this practice is an ever-moving target. FUNDAMENTALS OF COAL STORAGE Storage of coal is becoming an increasingly important part of coal handling systems at mines, particularly since the advent of the unit train concept in transportation. In order to take advantage of reduced transportation rates on trainload shipments of coal offered by unit train movement, operators have found that storage is an economic necessity. In unit train practice large predetermined quantities must be loaded in relatively short periods of time as opposed to conventional practice where coal is loaded at a speed dependent on the production capacity of the mine and/or the cleaning capacity of the preparation plant. Two surveys of storage practices at mines reveal several objectives for storage.1, 2 Raw and/or clean coal storage is generally practiced in order to accomplish one, or a combination, of the following objectives: 1. To improve plant efficiency by distributing plant feed over the entire operating time, or to allow a preparation rate different from the production rate. 2. To limit interruptions of supply, ie, allow mine and plant to function independently with delays in one not affecting the operation of the other.

Jan 1, 1968

By John D. Ridge

For mining geologists, the most important trends during 1962 have been the increased concentration of the exploratory activities of American mining companies in the United States and Canada and the greater use of the combined techniques of geology, geophysics and geochemistry in searches over larger areas for wider varieties of metals and minerals. The principal reasons for these changes in approach have been the deterioration of the political-economic climate in many areas of the globe of equal or greater geologic promise and the realization that modern exploration is most efficiently and economically conducted through the use of all available means of detecting ores in areas sufficiently large to raise to a maximum the chances of success. The attitude of certain major U.S. metal-producing companies can be shown by the officially ex- pressed positions of their principal officers. Early in 1962, Clyde E. Weed, Chairman of the Board of Anaconda, remarked that "because of unsettled conditions and disruptive influences in many of the copper-producing areas of the world, it is imperative that domestic copper-producing capacity be improved and made as efficient as possible in order to meet consumer demands at reasonably stable prices." In November, Robert G. Page, President of Phelps Dodge, pointed out that his company is not only concentrating most of its exploratory effort on this continent but is also increasing the number of metals for which it is searching. Frank R. Milliken, President of Kennecott, recently said that "most of our exploration money is going into the northern part of the Western Hemisphere."

Jan 2, 1963