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By AIME AIME

A MODERN copper reduction works has both a genera1 chemical laboratory for control work and a research laboratory for the study of improvement of present processes and better working-up of by-products. The division of work in the general laboratory would naturally differ in different plants. The following statement to the writer from a chemist in one of the works will give a good idea of the type. of work in the general laboratory :

Jan 1, 1929

By Sidney Swensrud

ABOUT a year ago, I attempted in a general way to trace the origin and development of some of the marketing problems of the petroleum industry, and to describe certain trends which it then seemed possible to foresee. To summarize briefly, it was pointed out that the consumption of gasoline, after increasing for more than a decade at an almost unbelievable rate, was slowing down, but that the two factors which determined the supply of gasoline-namely, the production of crude oil and the percentage of gasoline derived therefrom-were tending steadily to mount. It was suggested that, while the increase in gasoline outlets began with and probably was justified at the start by the rapidly increasing demand, long after all reasonable requirements as to number of outlets had been met the number continued to increase-if anything, at a still more rapid rate-because by that time the overproduction of crude had begun to exert an impelling urge upon the owners of that crude to seek assured outlets for it in the form of gasoline. As more and more companies became integrated all the way from crude oil to marketing, there took place an ever-increasing competition among them, not only for the existing outlets but for new ones. The wide margin between wholesale cost and retail price, which is characteristic of the early stages of most new industries, persisted in the oil industry longer. than in most industries, for various reasons. The existence of that wide margin provided in large measure the means of attracting new outlets, for as the gallonage per outlet declined with the increasing number of outlets, competing companies simply offered the dealers a larger part of the total margin. The very nature of competition suggests that such a process would continue until practically all of the available margin was thus given away, and such was clearly the, tendency. It was a system that in turn produced increasing marketing expense per gallon on account of the -diluted gallonage per outlet; this increased expense might seem to have provided a justification for continuing wide margins. Economics, like its parent, nature, however, progresses by mutations and so began to throw out new types of marketers, in the form cf tank-car service stations, cut-price jobbers, and the like-heretics or

Jan 1, 1932

By H. G. Doll

A new electrical logging method. called MicroLaterology is described. whereby the resistivity R of the invaded zone close to the wall of the bore hole is measured. This method essentially utilizes a system of concentric circular electrodes iml,edded in an insulating support which is applied to the wall of the hole. A beam of current of very small diameter is focused horizontally into the formations by means of an automatic control device. and then opens widely at short distance from the wall. with this method, R most often can be recorded directly. except when the mud cake is very thick. in which case a correction is easily provided. The basic role of factor R in the quantitative analysis of electrical logs in terms of fluid saturation and of porosity is explained. The paper is illustrated with field examples. INTRODUCTION In electrical logging. the resistivity of that part of the penneable and porous formations which is invaded by mud filtrate is an important factor in the interpretation. Measurements made with the conventional devices — normal. lateral — and also with improved systems as the Laterolog and induction logging' — are very often more or less affected by the presence of the invaded zone. and the knowledge of the resistivity of this zone is useful in the evaluation of the true resistivity of the beds. which itself is a basic element for the determination of fluid saturation. Moreover. the comparison of the resistivity of the invaded zone with the resistivity of the mud filtrate gives valuable indications on the magnitude of the formation resistivity factor — which in turn is necessary for the quantitative interpretation of the logs. both in terms of fluid saturation and of porosity. On the other hand. it is generally admitted that the invaded zone is not a homogeneous medium separated from the uncon-tamirlated part of the bed hy a well defined cylindrical boundary. but that the fluid distribution—filtrate. connate water. hydrocarbon — and hence. the resistivity. in the invaded zone varies progressively with the distance from the wall of the hole. The term "resistivity of the invaded zone" therefore corre-sponds to an average value which is a function of the distribution of the fluids Inasmuch as the law of this distribution is not exactly known, the resistivity of the invaded zone is not a well defined factor. A much better definition is obtained if the medium under consideration is limited to that part of the formation which is within a short distance from the wall of the hole. It seems likely a within a distance of at least two or three in., most of the fluids in in the pores of tile formation have been displaced by the mud filtrate. The connate water has almost certainly been flushed out. and the oil. if any has generally been reduced to a comparatively small amount. The resistivity witliir~ the radial limit of two to three in. is. therefore. prac.tically constant at an). given level: its value. at least when the proportion of conductive solids in the formation is negligible. is chiefly dependent on the resistivity of the filtrate and on the porosity of the formation, and is affected only to a relatively small degree by the presence of the small amount of residual oil. This part of the formation close to the wall of the hole will he designated in the following as the "flushed zone." a-distinguished from the more general term of "invaded zone'. which relates to the part of the formation extending from the wall out to the distance where the formation is completely uncontaminated. The symbol R,, will he used for the resistivity of the flushed zone. (The notation R is related to the radial distance from the hole. If x designates this distance. xo is the initial value of x, i.e., the value corresponding to the region very close to the wall.) The determination of R is difficult, if not impossible. from logs made with the conventional devices. The long normal and the long lateral are. of course. not suited for this purpose because their radii of investigation are by far too large. The short normal. and the limestone sonde—-after correction for the effect of the hole hole — give resistivity values which corre. spond to materials situated within a comparatively short distance from the hole, but this distance is still several time. as great as the thickness of tire flushed zone. The only value which can be obtained with these devices corresponds to an average resistivity of the invaded zone- — and this only provided the invasion is deep enough, since otherwise the meas "red values would also be affected by the uncontaminated region beyond the invaded zone. It should nevertheless be recalled that despite these limitations. the measurements given by the short normal and or the limestone sonde are always very useful for qualitative interpretation. and also in favorable cases for the qantitative analysis of the logs in terms of saturation and porosity. The MicroLog. which was primarily developed for the detection of permeable beds and for an accurate determination of their boundaries. provides a good approach towards the evaluation of R. In the case of hard formation.. however. The

Jan 1, 1953

By J. A. Retty

HOLLINGER CONSOLIDATED GOLD MINES LTD., through two subsidiary companies, has the exclusive right to prospect in two contiguous areas in central Labrador. This paper presents the results of the mineral exploration that has been conducted in these areas to date. One of the subsidiaries of Hollinger. the Labrador Mining and Exploration Co. Ltd., under an agreement with the Newfoundland Commission of Government, holds an area of approximately 20,000 sq.mi., which comprises the western portion of Newfoundland-Labrador and includes the upper basins of the Hamilton and Naskaupi Rivers. (The main area of the deposits so far discovered may be located on a map at about 67° west longitude and 55° north latitude.) The other subsidiary of Hollinger, Hollinger North Shore Exploration Co. Ltd., has licensed from the Province of Quebec an area of approximately 3900 sq.mi. lying directly north of the Newfoundland-controlled area at the headwaters of the George, Whale, and Swampy Bay Rivers. The M. A. Hanna Co., large iron-ore operators of the Lake Superior region, are participating in the project. With the exception of the years 1940 and 1941, field work has been conducted in the Newfoundland area since 1936, and in the Quebec area since 1939. Hollinger assumed the management in 1942. The field base is at Hollinger Lake, some 300 miles north of the tidewater base at Seven Islands, Quebec, which, in turn, is just west of the mouth of the Moisie River, on the Gulf of St. Lawrence. Air transportation is used exclusively to service the operation.

Jan 1, 1945

By W. A. Nagel, R. P. Alger, H. Sherman, J. Tittmann

A sidewall epithermal neutron tool has been developed to substantially reduce environmental effects that have previously complicated neutron log interpretation. Designed for operation in uncased wells, the device provides increased accuracy in both liquid-filled and empty holes. A brief discussion of neutron moderation, diffusion and capture shows that logs using epithermal neutron detection depend on a smaller number of formation-characterizing parameters than those using thermal neutron or capture gamma ray detection. Thus, they come closer to providing an unambiguorls determination of hydrogen content. In this new device a directionally sensitive epithertnal neutron detection system has been incorporated in a side-wall source-detector skid to minimize borehole effects. The effects of variations in borehole size and shape, mud type, temperature and salinity are greatly reduced. Small residual borehole effects are then computationally accounted for in the surface control panel to provide a borehole-corrected neutron log. The log presents a direct recording of neutron-derived porosity on a linear scale. With corrections for borehole effects already applied, this direct recording of porosity simplifies log interpretation. Furthermore, comparison with a linear porosity presentation of a formation density log permits sandstones, limestones and dolomites to be readily identified. Thus, in complex or variable lithology, porosity is determined with greater accuracy and reliability than heretofore. Laboratory data and field results demonstrate the improvements in neutron logging afforded by this new side-wall epithermal neutron logging device. INTRODUCTION The new Sidewall Neutron Porosity (SNP) logging system, designed for use in uncased wells, provides reliability and accuracy never before achieved with neutron logs. The effects of variations in borehole diameter and shape, fluid salinity, mud weight and temperature—parameters that have long complicated neutron log interpretation— are suppressed or corrected for by this sidewall epithermal neutron detection system. Furthermore, to simplify interpretation the SNP log presents a direct recording of computed porosity on a linear scale. The performance improvements achieved by this new system arise primarily from the combination of two im- portant design features. First. though not unique to this new tool, an epithermal neutron detection system is used,',' Epithermal neutron detection substantially reduces the perturbing influences of the thermal neutron absorption properties of rock matrices and water salinity. Second, the neutron detection system is mounted in a directionally sensitive sidewall skid to greatly minimize borehole effects. The purpose of this paper is to explain briefy the advantages offered by the detection of epithermal neutrons, to describe the SNP equipment and the log, to present calibration and correction data and to give examples of interpretation methods made especially convenient by this new system. ADVANTAGES OF EPITHERMAL NEUTRON DETECTION Epithermal neutron detection, of all the neutron methods in current commercial use, provides the simplest determination of formation hydrogen content. Advantages of epithermal neutron detectors, as compared with thermal neutron and gamma ray detectors, are probably best explained by a brief review of the life of a source-emitted neutron. A fast neutron from the source will eventually be cap-tured by the nucleus of an atom. However. before capture is likely to occur, the fast neutron (energy of 100,000 electron volts (ev) or more) will be slowed down until it is in thermal equilibrium with its surroundings. The neutron is then considered to be a "thermal" neutron (average energy of 0.025 ev at 25C). The overwhelming majority of the slowing down thus occurs in reaching epithermal energies (energies just above thermal—0.5 to several ev). After reaching thermal energy. the neutron will "diffuse" through the formation with, on the average, no further energy change until capture. Upon the capture of the thermal neutron, relatively high energy gamma rays arc usually emitted. Hydrogen plays a very important role in the process of slowing down fast neutrons. On the other hand, the absorption effects of water salinity and low concentrations of other strong thermal neutron absorbers—relatively unimportant in the moderation process-—are very important in thermal diffusion, capture and the production of gamma rays. Thus, by detecting only epithermal neutrons with the SNP, spurious effects due to these thermal neutron absorbers are greatly minimized as compared to the effects on tools using thermal neutron or gamma ray detectors. The epithermal neutron detection system affords another important advantage. Log response in various litho-

Jan 1, 1967

By Thomas W. Dawson

The H. C. Frick Coke Co. has used belt conveyers for handling coal for the last eighteen years but, until recently, only for small tonnages and over short distances. The first installations were outside the mines for distributing coal to various parts of plants. A belt conveyer was put in service at Colonial No. 4 Mine in November, 1906, to carry coal from the main hoisting shaft to a storage bin serving two blocks of beehive ovens on the other side of the valley; it was in constant service until the Colonial No. 4 ovens were abandoned less than a year ago. This conveyor was in an overhead gallery that spanned our sidings and yard tracks and the main line of the Pennsylvania Railroad. It was a crude installation, from the viewpoint of present conveyor engineering practice. It had no mechanical feeding device, the coal simply ran through a gate in the side of a bin on to the belt; but one belt on this conveyor lasted eleven years. This conveyor is about 300 ft. long center to center of pulleys. It operated at a speed of 250 ft. 'per min-and carried about 400 tons per day. On this basis, the belt life of eleven years means that not over a million and a quarter tons was carried by the belt. whi1e: this is not a large tonnage, the cost per ton was much less than by any previous method in use for supplying coal to ovens located at a distance from the main shaft. The next belt conveyor was installed at Bridgeport Mine in 1907. It carried about the same daily tonnage as the first, delivering from the hoisting shaft to a coke-oven bin. Very few data were kept on this conveyor. It also operated until the coke ovens at the plant were put out of blast and the coal taken to the Clairton byproduct plant by river. In 1916, work was started to equip the Bridgeport, Palmer, Gates, and Ronco mines to load their entire output on the river for transportation to the Clairton byproduct plant, which was then being built. These mines were all operating at that time and had a large area of coal available for river shipment. The Monongahela Railroad was located between the hoisting shaft and the river at each of these plants and, therefore, had to be crossed at each location to deliver coal to the river. After careful study, it was decided to transport this coal from the hoisting shaft to the river at each of these plants by belt conveyors.

Jan 1, 1925

By PERCY E. BARBOUR

TWO YEARS after its organization, the Institute issued its first volume of TRANSACTIONS, covering activities that began in May, 1871, and continued through February, 1873. The preface of this first volume reads: The present volume contains the rules of the Institute, a list of members and associates, an abstract of the proceedings of the-first two years, and a number of papers selected from those proceedings. There is, therefore, nothing new in it. The papers have all been published, according to the custom of the Institute, in the Engineering and Mining Journal, and many of them have been copied into other periodicals. They are republished here, solely to enable members and associates to preserve them in convenient form. Various considerations have determined the selection of papers for this purpose. Some have been omitted at the request of the authors who, having modified the views expressed in them, naturally deprecated a republication of those views. Others have been omitted, in order not to devote too large a proportion of space to single topics, or single branches of mining or metal¬lurgy, in view of the fact that the membership of the Institute extends throughout the whole country, and represents numerous departments of these industries. Some, on the other hand, have been chosen, although not laying claim to special originality, because they contained information of importance, not easily accessible elsewhere, the presentation of which, in a form convenient for reference, was generally desired.

Jan 1, 1921

By Byron E. Eldred

(Pittsburg Meeting. March, 1010.) GENERALLY speaking, the practical study of combustion has been made mainly from the stand-point of the steam engineer. This. narrow view-point has left open a large field for scientific research on the application of combustion in other arts, where the conditions of heat-utilization are widely different from those presented in the steam-generator. The great economic importance of the boiler and the ease of measuring its performance, together with the comparative uniformity of conditions in the steam-generator, is, probably, quite largely responsible for the practical neglect of the study of the use of fuels in other arts save only on the basis of their thermal value. Yet these other arts show quite plainly that a thermal-value basis alone is Dot sufficient. For example, in burning lime, under ordinary conditions of firing, a cord of wood will do as much work as a ton of coal, though the latter affords more than twice the number of heat-units. Similar results are evidenced in burning brick, in the roasting of certain ores, in reheating billets, and in many other arts where heat is to be applied over extended areas to fragmental masses of more or less refractory materials. In these arts much is to be gained by a careful study of the application of the heating-agent in the form of the long flame, and in the production of the heat in contact with, or in direct proximity to, the object to be heated. Of necessity, in boiler-practice, combustion cannot be maintained in actual contact with, or in close proximity to, the object to be heated. Speaking in a general way, heat is imparted from burning bodies to things to be heated in two ways : directly, by radiation, and indirectly, by transfer of the sensible heat of hot gases by convection or contact; by conduction from the hot uses. Both ways are utilized in boiler-practice-directly, by

Jun 1, 1910

By W. S. Tower

STEEL is the basic metal, the main metallic prop of the modern industrial world, a good gage for measuring the state of our complex economy. Any who had doubts on that score should have had them dispelled by the many evidences of public concern over the affairs of the steel industry in recent months. I do not need to relate the various criticisms of the industry, nor the questions about its policies and performance which have come in a rising flood, especially from unthinking and irresponsible sources. But judged from the standpoint of production, or from plans to improve and expand facilities, or from technical progress, the facts about the steel industry are proof of

Jan 1, 1948

NEW MEMBERS The following list comprises the names of those persons who became members during the period of Nov. 10, 1917, to Dec. 10, 1917. ADAMS, LLOYD D Supt., Hoskins Mine, Mineral Point Zinc Co., Galena, Ill. ARMSTRONG, WILLIAM D., Min. Engr.. Empire Coal Co., 715 American Trust Bldg., Birmingham, Ala. BALL, TOM LEE, Efficiency Engr., Iron Mines Dept., Tennessee Coal, Iron &.R. R. Co., Bessemer, Ala. BENZIE, WILLIAM ROSE, Sec. & Treas., The Republic Coal Co., 901-2 Foster Bldg.,Denver, Colo. BERGSTROM, GUNNAR, Min. Engr.... Resident Mgr., Russian Dept., Swedish Diamond Rock Drilling Co., Slatawostowskaja Ulitza 6, Ekaterinburg, Russia. CADOT, J., Engr.,. Hardinge Conical Mill Co., Newhouse Bldg., Salt Lake City, Utah. COFFEY, GEORGE W 64 Santa Clara Ave., Oakland, Cal. CUTLER, WILLARD WALKER, JR Geol., Carter Oil Co., Tulsa, Okla.' . DANIEL, JOSEPH A., Min. Engr. & Geol., Hudson's Bay Co., Care The Institution of Mining & Metallurgy, 1 Finsbury Circus, London, E. C., England. EARDLEY, WALTER HAZEN, Cons. Engr., Chanute Spelter Co., 316 Frisco Bldg Joplin, Mo.

Jan 1, 1918

By C. A. Wert

THE solid solubility of cementite in a-iron has been investigated a number of times and there is now general agreement on the solubility of about 0.018 wt pct at the eutectoid temperature, 720°C. With decreasing temperature, the solubility falls off so rapidly and to such a low value that no data obtained by standard metallurgical methods are available below 500°C. Using a new technique, however, Dijkstral has obtained apparently accurate solubilities down to 400°C; which data agree well with previously measured solubilities in the 600" to 700°C temperature range.' The present paper has in part the purpose of extending his work to still lower temperatures. Earlier work of Low and Gensamer3 on iron has established that the presence of a relatively small amount of carbon can play a tremendous role in affecting the mechanical properties. In particular they found that the yield point remained high as they reduced the amount of carbon in the iron; the yield point dropped only after the carbon content had fallen to something less than 0.003 wt pct, the point where their carbon analysis failed. It seemed desirable to the present author to see if some means could not be found to extend this part of their work. This investigation has then the additional purpose to determine the range of carbon concentration in which the major change occurs. Solubility The method used in the present work to measure small percentages of carbon in a-iron utilizes internal friction. Since this method may not be fa-miliar to the reader, the following explanation will be given (a part of this procedure is from unpublished results of Dijkstra): It is known that the internal friction associated with the diffusion of

Jan 1, 1951

By Charles W. Eichrodt

So much has already been wimitten on this vast subject of ground movement and subsidence, and so many data collected and commented upon, that in this paper the author proposes to confine himself to the submission of some plans showing what has actually occurred in the mining of several of the orebodies which have come under his direction during the last 20 years or so at Rio Tinto, Spain. Some notes are added for the purpose of describing the plans. The author does not attempt to give his opinion as to the reasons why the subsidences have occurred in the manner in which they are found, but confines himself to giving as true a picture as possible of the movements that have taken place. Effects of Excavation on Ground Movement Broadly, the effects of excavations on the overhead or adjacent ground can be classified under three headings, as follows: 1. Ground movements due to excavations made from surface only, such as those made in opencasts where no excavations underlie them. The stability and strength of the ground to resist movement must determine the slopes. 2. Ground movements due to underground excavations only; i. e., where the surface is not removed. 3. Ground movements due to a combination of both; i. e., from excavations taking place from the surface for the purpose of stripping an orebody and recovery of the ore to a certain horizon combined with excavations being carried out below, at the same time, for the winning of the ore below the horizon at which mining by stripping or opencasting under the specific conditions is no longer economical. Nos. 1 and 2 represent independent and distinct problems and No. 3 is a combination, which presents results much more difficult of explanation. The accompanying plans and sections give examples of what has occurred under the three conditions. Unfortunately, the class of ground is not exactly the same in them all, but the difference is not greater than is generally encountered over districts of equal area. Excavations from Surface To illustrate No. 1 three cross-sections are shown, of excavations made for the stripping and excavation from three different orebodies

Jan 1, 1930

By J. Wes Blakely

In the mid-1950s the importation of foreign oil began to encroach on traditional coal markets such as railroad steam engine fuel, home heating, electrical generating plants, and others. Many of the smaller coal companies with substantial coal reserves subsequently found that they could no longer continue to mine economically and merged in various ways with larger established coal mining concerns. As the seats of top management and authority were removed from the mines to large metro centers such as New York, Pittsburgh, and Chicago, the more personal relationship between mine workers and management that had existed prior to these mergers began to be eroded and replaced by "remote control" mine management. The disappearance of this face-to-face contact of upper management with mine employees tended to create barriers blocking simple effective communications between coal mine management and labor. In examining the human relations aspects of the coal mining industry, many elements, some concerned with work and others not, have depicted the industry as almost devoid of good applied human relations and communications practices, and, in truth, little has been done to alleviate this situation. In past years many coal producing companies, with the exception of one of the largest, failed to adequately define the term "communications ' as it applied to their companies, whether internally or externally. Internally many still place heavy reliance on written communications such as company-wide newspapers to do the job of communicating with their employees which they feel ought to be done. One company puts an inordinate belief in its company "newspaper" as the primary instrument to stimulate its work force into increasing productivity. Primarily aimed at the workers, who greatly outnumber the salaried administrative people, this publication mainly documents the fortunes of individual mine workers who are felt to have achieved something with their lives, e.g., a mine worker who had managed to put four children through universities, the

Jan 1, 1981

By S. Le Fevre

The application of electricity to the mining and beneficiation of the magnetic iron ores of the Mineville, N. Y., district, on Lake Champlain, has resulted,in economies and enhanced quality of product, without which only a comparatively small quantity of the present output could be marketed. The output of the Witherbee, Sherman & Co. mines is about 700,000 tons per annum, and of this about four-fifths is treated by magnetic separation to increase the iron content and reduce the phosphorus. The use of electricity for the magnetic separation of the ore from the gangue is therefore of primary importance, and makes possible the application of electric power for mining and preparing the ore for concentration. The fact which speaks loudest in favor of the application of electricity is this: It is possible for about 25c. per ton of shipping ore to furnish all the power required to put the ore on cars. This includes mining a hard ore underground, from a depth of 900 ft., hoisting to surface, crushing to $ or 8 in. in size, and separating from the gangue. This also includes lights about the works, and all miscellaneous power, such as about the shops. The first plant for the generation of electric power for use at Mineville was completed in 1903, and was one of the first for the application of electricity to mining iron ore. This was a Nordberg compound condensing steam engine, direct connected to a 750-kw. alternating-current generator, 3,300 volts, 3 phase, 25 cycles. All the plants added later use the same current but with higher voltage. The map, Fig. 1, shows the power plants and the transmission system; Figs. 2 and 3 are views of the shaft houses and the mills. The power from the first plant was distributed to Mills 1 and 2, one 2,500 cu. ft. compressor, and to the Harmony hoist, which was driven by a 300-h.p. motor operating four 10-ft. drums. Our experience with the hoist covers largely the development of electric hoisting from 1903 to date, and in some cases improvements were worked out to satisfy our needs. The motor is still operating as installed, but the control apparatus has been radically changed several times. When installed, the iron re-

Jan 1, 1915

NEW MEMBERS The following list comprises the names of those persons who became members during the period Nov. 10, 1916 to Dec.10, 1916. BARNSDALL, THEODORE N., Treas. & Mgr., Highland Gas Co., 24 West Corydon. St., Bradford, Pa. BEASLEY, FRED E., Asst. Supt., Copper Refinery, Consolidated Mining & Smelting Co., Trail, B. C., Canada., BREWSTER, THOMAS T., Vice Pres., Gen. Mgr., Mt. Olive & Staunton Coal CO., 1012 Federal Reserve Bldg.,-St. Louis, Mo. BRINDLE ARTHUR ST. C.... Mining Recorder's Office, Trout Lake, B. C., Canada. BULLOCK, Harry E., Pres Kentucky-Jewel Coal Co., Lothair, Ky. BUTLER, PERCY BENNETT, Mine Operator :..P. 0. Box 335, Joplin, Mo. BUTLER, ROBERT S Supt., Three Johns Mining CO., ,Joplin,.Mo. CABOT, Godfrey, L., Carbon Black Maker, Gas Engr., 940 Old South Building Boston Mass.

Jan 1, 1917

Organization Place Date 1919 Automotive Engineers New York, N. Y. Feb. 4-6 American Institute of Mining Engineers New York, N. Y. Feb. 17-20 New England Association of Gas Engineers Boston, Mass. Feb. 19 American Institute of Electrical Engineers New York, N. Y. Feb. 19-21 National Society for the Study of Education Chicago, Ill. Feb. 25-28 American Railway Engineering Association Chicago, Ill. Mch. 18-20 American Electrochemical Society New York, N. Y. Apr. 3-5.

Jan 2, 1919

OFFICERS AND DIRECTORS For the year ending February, 1935 PRESIDENT AND DIRECTOR HOWARD N. EAVENSON PITTSBURGH, PA. PAST PRESIDENTS AND DIRECTORS SCOTT TURNER WASHINGTON, D. C. FREDERICK M. BECKET NEW YORK, N. Y. VICE-PRESIDENT, TREASURER AND DIRECTOR KARL EILERS NEW YORK, N. Y. VICE-PRESIDENTS AND DIRECTORS EUGENE MCAULIFFE OMAHA, NEB. PAUL D. MERICA NEW YORK, N. Y. HENRY KRUMB SALT LAKE CITY, UTAH EDGAR RICKARD NEW YORK, N. Y. LOUIS S. CATES NEW YORK, N. Y.

Jan 1, 1934

By F. G. Tahmoush, N. J. Grant, E. P. Abrahamson

The effect of grain size on the brittle -ductile transition temperature of pure iron and three dilute Fe-W alloys has been investigated by slow bend tests. The brittle-ductile transition temperature for pure iron increased with increasing grain sizes from 8000 to 500 grains per sq mm where the transition temperature then decreased with further increase in grain size. The dilute additions of tungsten lowered the transition temperature for fine grain sizes, suppressed a reversal of the curve in the coarse grained portion, and raised the transition temperature for this region. The frequency of twin occurrence increased with increasing grain size and decreasing temperature. The object of the present investigation was to re-examine the effect of grain size on the brittle -ductile transition of pure iron and several dilute Fe-W alloys. Current literature normally presents a simple relationship between grain size and the brittle-ductile transition temperature, namely, that the transition temperature increases with increasing grain size. Heslop and etch' have studied the transition temperature of mild steel by V-notch Charpy impact tests for the grain size range between 200 and 6000 grains per sq mm. The result was a linear plot of In 1-1/2 vs brittle-ductile transition temperature, where 1 is the grain diameter. Recent experiments by sipos2 revealed the possibility of a reversal in the slope of the grain size vs transition temperature plot for pure iron; however, his investigation was limited in scope, and the data obtained were insufficient to permit a definitive curve. The present investigation was undertaken in an effort to confirm or extend the grain size effect observed in iron by Sipos. PROCEDURE All alloys were vacuum induction melted, using 99.95 pct Fe containing 0.03 pct 0 and 0.004 pct C. Four ingots were made, ranging from pure iron to iron with 0.035 pct W. The chemical composition of each alloy, after processing, is given in Table I. The four alloys were prepared as 45 lb heats and cast into 4 in. diam by 16 in. molds. They were then extruded into 3/4 in. rods at 1800oF. Specimens for chemical analysis, taken from various positions along the rods, revealed no variation in tungsten content along the length. The extruded rods were reduced to 0.156 in. diam stock by a series of cold swaging operations involving intermediate vacuum annealing treatments. This procedure yielded a final cold reduction in area ranging from 10 to 90 pct. The swaged rods were chemically cleaned, cold pressed to a cross section of 0.10 by 0.18 by 1.0 in. long (2.54 by 4.73 by 25 mm). The specimens were wrapped in iron foil and vacuum sealed (10-4 mm Hg) in quartz. Various heat treatments at temperatures from 700" to 1300oC were utilized to produce grain sizes from 8000 to 1 grain per sq mm. Grain sizes were determined by measuring the average area of grains in a polished section. In specimens with grain size greater than 20 grains per sq mm, the total number of grains in the cross section was counted and then divided by the area to yield grains per sq mm. Grain size was measured both for longitudinal and transverse cross sections. The average of the two measurements was plotted vs transition temperature. An Instron Table Model testing machine was used to determine the transition temperature of specimens tested in three point horizontal bending. The specimen was supported by two 1/4 in. dowels one in. apart. Bending was accomplished with a push rod, the end of which had an 1/8 in. radius. The head speed was 50 in. per min. Temperatures were established through the use

Jan 1, 1963

By A. D. Schwope, L. R. Jackson, K. F. Smith

Burghoff and Blank1 have pointed out that the creep properties of hard-drawn coppers are closely associated with their individual softening characteristics and have further shown that the creep resistance of various types of copper is improved, under certain circumstances, by cold stretching. In the design of certain types of electrical machinery, it is important to have the creep resistance as high as possible; furthermore, short-time creep strength is important since in many cases stresses are large only during warming-up and cooling-down periods. In this paper, data are presented showing the effect of cold work on the short time creep strengths of various types of commercial copper under several conditions. It is shown that trends from short-time creep tests are evident at longer times. Materials Used in the Investigation The coppers used in this investigation were commercial grade and of two basic types, oxygen free high conductivity (OFHC) and tough pitch. Additions of silver in amounts of 15 and 25 oz per ton were added to each of the two coppers. The analyses of these six coppers are given in Table 1. Originally, they started as wire bars 4 X 4 X 54 in. A. square rod was made by hot rolling the wire bars to 9/16-in. rod in 8 passes. This rod was then cold drawn to 0.445-in.-diam rod and annealed for 3 1/2 hr at 1000°F. It was then cold drawn to 0.325-in. rod and again annealed at 1000°F for 3 1/2 hr. Hard square rods were then made by cold rolling to 0.257 X 0.257-in. rod. Soft wire was made from the hard- drawn material by annealing at 650°F for 3 hr. The final rolling was performed using a set of 9-in. grooved rolls revolving at 30 rpm, which produced square wires. Reductions of approximately 5, 20, 30, and 40 pct were obtained using several passes in the same direction for the large reductions. The 5 pct reduction by drawing was accomplished using a steel die having 2 parallel bearing surfaces. The die angle was 7 1/2 degrees and the wires were lubricated with a paste of ceresin wax dissolved in carbon tetrachloride. The speed of drawing was 13 fpm. Since work was done on only two sides of the wire simultaneously, it was necessary to rotate it 90 degrees each pass to insure uniform deformation. The room-temperature tensile properties of the various tempers are given in Table 2. The grain size of the an- nealed 0.257-in. wires was uniform and averaged about 0.035-0.045 mm. Experimental Procedures for Short-time Creep Tests Standard creep-test frames (Fig 1) were used for the testing. Special fixtures were designed to apply axial compressive and tensile loads to the copper wires. The compression specimens were 1 in. long and the ends were ground flat and parallel. The creep in compression was indicated by the movement of reference marks s-ratched on intersliding platinum strips attached to the moving heads of the fixture. The movement was measured with an optical micrometer fitted with a filar eyepiece on which the smallest division was 0.00005 in. The tensile creep specirriens were 4 in. long which provided ample gripping surface for the jaw-type grips. The platinum strips were attached to a one-inch gauge length of the wire and the creep measured as previously described. The single-specimen furnaces were connected to individual power and control sources. The controlling equipment consisted of Foxboro controllers

Jan 1, 1950

By P. Chiotti, J. T. Mason

Thermal, X-ray, metallographic, and resistivity data were obtained to establish the phase diagram for the Yb-Zn system. Six intermetallic compounds and five eutectics have been identified. The compounds position at 695°C. No evidence for the compound YbZn,, was observed. Whether this compound is stabilized or inhibited by small amounts of impurities is uncertain. SEVERAL aspects of the Yb-Zn system have been reported in the literature. Much of this work deals with the crystallographic identification of some of the compounds. The YbZn compound has been reported by Iandelli and palenzonal and the YbZn, structure and thermal data for the composition range between YbZn and Yb3Znll have been reported by Michel et al. A compound of uncertain stoichiometry in the range 60 to 68 wt pct Zn with a cubic structure has been reported by Kuz'ma et aL4 The YbzZn17, YbZn,,, and YbZn13 compounds have been reported by both Kuz'ma et a1 and Iandelli and Palenzona.' YbnZn17 has also been identified by Laube. This investigation was undertaken to establish the phase diagram of this system. Ytterbium in many respects behaves as an alkaline earth rather than a rare earth metal6 and it is of interest to note the resemblance between the Yb-Zn system, the Ca-Zn,' and typical rare earth-zinc systems.g'10 MATERIALS AND EXPERIMENTAL PROCEDURES The materials used in this investigation were Ames Laboratory ytterbium and Bunker-Hill slab zinc, 99.99 pct pure. Analyses of the ytterbium showed 38 ppm Ta, 82 ppm 0, and 15 ppm N with Ca, Cu, C, Mg, Al, Si, Cr, Fe, Ni, Sc, Y, Er, Tm, and Lu all less than 50 ppm. The ytterbium was dehydrogenated by heating in tantalum under vacuum for 8 hr at 900°C. The metal was kept under argon except when being cut with shears and when being weighed. Tantalum was found to be a suitable container for alloys in the composition range between ytterbium and Yb2Zn17. With higher zinc concentrations the tantalum was penetrated by the alloy and failed after several days at temperatures of 600" to 700°C. Approximately 20 g of zinc and ytterbium metal were sealed under argon in *-in.-diam tantalum cruci- bles equipped with thermocouple wells. The crucibles were in turn sealed in stainless-steel jackets. The alloys were equilibrated in an oscillating furnace and given various heat treatments in a soaking furnace. The steel jackets were removed and differential thermal analysis data were obtained under an atmosphere of argon. The thermal analysis apparatus was calibrated against the melting points of pure zinc, aluminum, silver, and copper and found to give thermal arrests within 1°C of the accepted melting temperatures for these elements. The thermal analysis apparatus has been described in an earlier paper.g Alloys were further heat-treated as necessary and subjected to metallographic examination and X-ray diffraction analysis. Most alloys were etched with Nital (0.5 to 10 pct nitric acid in alcohol). EXPERIMENTAL RESULTS The results of the thermal analysis are summarized by the points on the phase diagram, Fig. 1. Six compounds and five eutectics were observed. The eutectic temperature and compositions in weight percent zinc are 491°C and 12 pct, 645°C and 32 pct, 687°C and 54 pct, 742°C and 67 pct, and 750°C and 77 pct. The compounds YbZn, YbZn2, Yb2Zng, Yb2Zn17, and YbZnll melt congruently at 650°, 751°, 75Z°, 754", and 755"C, respectively. The compound Yb3Znll undergoes a peritectic decomposition at 695°C. The transformation and melting temperatures for the ytterbium were observed to be 797" and 817°C. re-

Jan 1, 1969