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By David White

Jan 1, 1925

By F. N. Rhines, A. S. Nemy

The mode of high-temperature tertiary creep of 523-0 aluminum alloy was found to be strongly stress dependent. The occurrence of necking and/or fissures during tertiary creep exhibited a sequence with varying stress, wherein fissures with no necking occur at a minimum stress and necking with no fissures occur at a maximum stress. At an intermediate stress, tertiary creep begins without necking but with fissures in a region just beneath the external surface, followed by necking and the development of fissures along the axis of the specimen. The results are interpreted in terms of grain boundary gliding and the hydrostatic stresses produced by restraints to grain boundary gliding. THERE appear to be two possible reasons for the existence of a period of accelerating elongation prior to rupture during high-temperature creep in metals; namely, 1) a change in the structure of the metal itself, leading to a change in its response to loading, and 2) a reduction in the cross section of the metal resulting in a higher unit loading. Howe,' by annealing and retesting broken low-temperature creep specimens, found that irreparable damage is done once a metal is subjected to creep. Andrade2 first pointed out the association between the reduction in cross section and the increase in creep rate. The present research was designed to investigate both of these factors by retesting specimens machined from material which had been subjected to high-temperature creep testing short of rupture. EXPERIMENTAL METHOD An aluminum alloy, 52s-0, was selected for these studies because it is constitutionally simple, is strong enough to be relatively insensitive to mechanical damage during machining,3 and undergoes accelerating creep in a convenient temperature range. This alloy is hardened by 2.6 wt pct Mg in solid solution and is not subject to overaging effects; it has a very small quantity of an insoluble impurity phase, Mg2Si, finely dispersed throughout its micro-structure. Creep specimens, similar in design to ASTM 0.252-in. tensile specimens, were machined from 3/4-in. round stock and the surfaces were electro-polished. A 24-hr anneal at 500°C was then applied to stabilize the grain size to an average diameier of 0.27 mm. Subsequent heating for as long as 700 hr at the intended test temperatures produced no change in the tensile properties, indicating a well-stabilized state of the material. Corresponding to each of the typical testing conditions listed in Table I, one creep specimen was tested to destruction and this test was employed as a guide in the selection of times for subsequent tests. Duplicate creep tests were then run to various points along the creep curve to produce specimens which were used to determine changes in mechanical properties and microstructures. The latter were examined at the midsections of the specimens. Other specimens were tested to various stages of tertiary creep, after which they were remachined to new cylindrical test specimens, electropolished and re-tested in creep. RESULTS The major findings of this investigation may be illustrated by a comparison of the results of three sets of creep tests. These were run at 400°C at three stress levels, namely 750, 1000, and 1500 psi. In presenting these results in Figs. 1, 5, and 8, the creep curves are given in pairs: That curve of each pair which is drawn through filled circles corresponds to the initial test, and the curve drawn through open circles (and designated by - R) represents the result of retesting the same specimen after machining to a new cylindrical surface. The load was readjusted to the original unit stress at the beginning of each retest.

Jan 1, 1960

[I-Institute of Metals Division PAUL D. MERICA, Chairman ZAY JEFFRIES, Vice-chairman W. M. CORSE, Secretary General Committee ROBERT J. ANDERSON H. C. JENNISON L. W. SPRING WILLIAN K. FRANK DAVID LEVINGER R. L. SUHL J. R. FREEMAN, JR. PAUL McKINNEY R. F. WOOD]

Jan 1, 1928

By E. P. Pfleider

Important economic planning by industries, companies, financial firms and governments is predicated on estimates of future growth potential. Prior to the passage of the Taconite Amendment by the people of the State in November 1964, various admittedly conservative forecasts were made of the future of Minnesota's iron ore industry. Since that date, 3 new taconite plants are under construction, 2 are being expanded, one has just gone "on stream," and a seventh is in the design stage. These plants have a total capacity of about 35 million tons of pellets annually. The pessimism of 1964 today is being replaced by unbounded optimism. In the light of such recent developments, it becomes essential to update forecasts related to production, employment and capital investments. New projections show 50 to 58 million tons of pellet production from Minnesota by 1975. This tonnage, together with some 6 to 8 million of natural ores, should provide an annual full-time employment of 15,000 by the mining companies, plus 700 in related railroad and power producing activities and 1000 in plant construction. Total capital investment in new plants should reach $1.5 billion by 1975 and $2 billion by 1990. These current estimates indicate that the conservative goals as set in 1964 for the year 1990 should actually be achieved by 1975 or 1980. BACKGROUND Various forecasts1,2,3 have been made of the future consumption and production of iron ores within the United States. The most recent of these is by Harrison,1 delivered at the American Mining Congress meeting in Las Vegas in October. His estimates reflect the latest iron ore developments on a world wide front as well as the accelerating trend toward pellets. Minnesota's Natural Resources council prepared a detailed report in 1964 outlining the various factors that affect the future of Minnesota's iron ore industry. It presented estimates predicated on the

Jan 1, 1967

By W. H. Bassett, C. H. Davis

ALTHOUGH brasses and bronzes have been made for ages, a systematic study of their physical properties has been carried out only during the years of the present century. Among these properties may be included those which are to be detected by means of microscopic examination; in other. words by the science of metallography. The earlier workers in this field, both in this country and abroad, gave their attention to steel. When the senior author explored the situation in 1902, there was little encouragement to be found in undertaking the study of the non-ferrous alloys. A start was made, and the metallography of the brasses and bronzes, as well as of the copper-nickel-zinc alloys developed materially under his direction. Annealing experiments were begun in 1902, and in the succeeding years the effect of temperature, and the influence of previous working, on the grain size of brass were studied. The conclusions so well known and widely published today were largely reached during those earlier years. . In 1905 the first complete annealing series were made. By this it is meant that brass and copper sheet, 5 B & S Nos. hard, was machined into tensile test specimens, then annealed under accurate control for 30 min. at temperatures up to the melting point of the material. Various determinations were made, including tensile strength and elongation in 2 in. There rapidly followed similar series on all of the copper-zinc alloys from 100 to 60 per cent. copper, on the bronzes, cupronickels, and on copper-zinc-nickel alloys. At this point there was published by Grard, in October, 1909,1 the very comprehensive and complete work on the tensile properties of cartridge brass, 90-10 copper-zinc, and electrolytic copper. The excellent photomicrographs in that paper illustrated the changes in structure produced by cold rolling as well as by annealing at different temperatures, but where Grard's work was confined to copper and to two alloys, the investigations in this laboratory have been over the entire fields of the commercial copper-zinc alloys, copper-tin alloys, representative copper-nickel and copper-nickel-zinc alloys as well as aluminum bronzes and others of a more special nature.

Jan 1, 1928

By E. O. Wagner, V. F. Parry

This paper summarizes investigations during 1949 on three pilot plants for drying low-rank fine cool by entrainment in hot gases. Detailed operating results on processing seven coals having moisture ranging from 24 to 62 pct, formulas and data for calculating performance of large units, and general conclusions on the problem of drying fine coal are presented.

Jan 1, 1950

By Walter W. R. May

FOR more than 25 years a few business men who represent virile private enterprise in the Pacific Northwest have been trying to awaken the community to the potential benefits of an open Columbia River. No threat of government com- petition then hung over the industry, which was adjusted to state regulation. Numerous sites were engineered and the findings were laid before the operators of heavy industry in the East, Middle West, and South -even of Europe. These engineering data became, if not the basis, the inspiration upon which the U. S. Army Engineers eventually were to "build the Columbia River Bible" - their great document known as House Document 103, the report on the Columbia River and minor tributaries.

Jan 1, 1940

By J. Gurland

The effect of four different second-phase additions on the strength of composite alloys with a common matrix was investigated. The four compositions each consisted of 85 pct by volume of silver with additions of 15 pct of either tungsten, molybdenum, tungsten carbide, or nickel. These particular additives were chosen because of their low mutual solid solubilities with silver at room temperature, the alloys consisting essentially of a dispersion strengthened silver matrix in which the second phase is distributed randomly. Test specimens were prepared by a powder metallurgy procedure consisting of ball milling the mixed powders, compacting, and sintering at 920°C for 1 hr in hydrogen. The constituent powders were of CP quality and of particle size between 2 and 10 ?. The compacts were subsequently hot pressed at 1000 psi and 1400° in an Inconel die, coined at room temperature at 60,000 psi and finally annealed and outgassed in vacuum at 800°F. The microstructures of the alloys are shown in Fig. 1, and the microscopically observed porosity grade was A-2 or better as evaluated by ASTM Recommended Practice B 276-54. The properties of the sintered compacts are listed in Table I, and the load-deformation curves in bending are shown in Fig. 2. The samples, of rectangular cross section, were loaded at the center of 58 in. span, and the reported stress was calculated on the basis of linearly elastic behavior in order to allow the comparison of specimens of slightly different dimensions. It is apparent that the tungsten, molybdenum, and tungsten carbide alloys exhibit very similar deformation curves. The moduli of elasticity were determined from the slopes of the stress-deflection curves at small loads. The measured values agree quite well with those calculated by the strength of materials approximation proposed by Paul1 for the elastic constants of mixtures, the calculated values being 15.0, 15.0, 17.4, and 13.4 million psi, respectively, for the tungsten, molybdenum, tungsten carbide, and nickel combinations with silver. The strength of the Ag-Ni composition is appreciably lower than that of the other three alloys. The discrepancy between the two groups is accounted for by the following characteristics of deformation and failure which were observed microscopically during the tests: A) The deformation of the W, Mo, and WC alloys did not involve the second phase particles to any appreciable extent. Slip and fracture took place in the silver-rich matrix alone, although the fracture path generally skirted the particles by favoring the phase boundaries. The deformation proceeded according to the following sequence: 1) formation of small, discontinuous microcracks in areas of the matrix adjacent to a particle, 2) general slip in the matrix and extension of cracks, 3) failure of specimens by propagation of cracks through matrix. The near coincidence of the 3 load-deflection curves suggests that the nature of the second phase particles does not decisively influence the plastic behavior of composite alloys of this composition as long as the particles do not undergo any considerable deformation themselves. B) A markedly different behavior was exhibited by the Ag-Ni composition where the relatively low flow strength is associated with the low yield strength of the nickel grains. Slip in the nickel grains was first observed at a stress of approximately 10,000 psi, although failure, at a later stage, took place by the propagation of cracks through the matrix. The ductility of this aggregate, in which both components deform plastically, is appreciably greater than that of the elastic-plastic composites. In summary: 1) The measured values of the moduli of elasticity of the composite alloys under discussion are in good agreement with the "strength of materials" approximation proposed by Paul.' 2) The overall plastic behavior of these particle-strengthened alloys is unaffected by the nature of the second phase particles, if the latter remain elastic. This work was supported by the Office of Naval Research. The experimental results are presented

Jan 1, 1962

By James P. Kimball

AMONG the curious results of the recent advance of prices in the iron trade of the United States, one of them at least is to be regarded as of great importance. I allude to the utilization of mill cinder as a cheap and almost costless substitute for high-priced iron ores in many blast furnaces, situated within easy reach of such raw material. It has been, with but few exceptions, the practice in this country, based upon tradition rather than upon authority or European precedents, to waste this material on 'account of its high proportion of silicic and phosphoric acids, although known to contain more iron than most ores, and although also known to be sometimes applied to the blast furnace in greater or less quantities without serious detriment to the iron for specific purposes. While in use to a limited extent in the Hocking Valley and Hanging Rock iron regions of Ohio for several years, its use in Western Pennsylvania has only become general of late, under the exigencies of high prices and a short supply of ore. Especially has mill cinder largely entered into the stock of furnaces attached to rolling mills in and about Pittsburgh. Under such circumstances the cinder pig has been paddled on the premises, and the malleable iron produced has been unexpectedly good. Cautiously as at first mill cinder has been applied, it is evident that the temptation to use it freely is a strong one whenever the commercial rates for high-class ores are out of proportion to the general conditions of the iron trade, as sometimes happens in this country, especially as the free use of it is apparently justified by the quality of the iron produced from this cheap and abundant material. Indeed the consumption of cinder pig has., not been wholly confined to mills using up the production of furnaces belonging to the same plant. One furnace at least on the Ohio, at Covington, for several' months has been making foundry pig from "all cinder." The iron has gone into the general trade. It is probable that malleable iron of good quality can he made from the poorest cinder pig, but with what degree of economy will

Jan 1, 1881

By AIME AIME

A DOCUMENT of progress and of great interest to engineers is the report of the Military Affairs Committee of 'the Engineering Council, which has just been accepted and sent to the secretary of War. It provides .a plan whereby civilian engineers holding commissions in the Reserve Corps may; with their con- sent, be called into service of the army during peace at any time, either with troops in the field or in a consulting capacity on any government engineering work. The Military Affairs Committee finds ample authority in the military bill passed by Congress on June 4, 1920, for this arrangement and also for extending the privilege to military engineer, officer-s of the regular army to engage in civilian work during times of peace. It is hoped that the Secretary of War will adopt the suggestions and put the program outlined into effect. This is a constructive piece of work comparable to the efforts of the military Committee before the war which developed so much in the way of preparedness, particularly in the program of military lectures which, held in the auditorium in the Engineering Societies Building, became so popular that each lecture had

Jan 1, 1920

By AIME AIME

MOTHER example of the broad field that is covered by the mining industry is the recent erection by the Phelps Dodge Corp. of a modern hospital building at Douglas, Ariz., and an identical one at the rejuvenated mining town of Morenci. Managers of even small mining properties are often called upon to build schools, houses, stores, maybe a jail, and provide sanitary arrangements, possibly the while acting as mayor of the town. Those who direct larger properties may have to build hospitals, as in the present instance, construct sewage disposal plants, and sometimes even build and manage railroads. A mining camp achieves its reputation among mining men not entirely by the grade or amount of its ore, or the skill of the operating staff in mining and milling it at a profit-the operation soon acquires a reputation as either a desirable or an undesirable place to live, regardless of its remoteness from what is euphemistically termed civilization. Such a community is indeed fortunate if it can boast of a good hospital.

Jan 1, 1940

By Richard W. Smith

Why are we losing our liberties? (1) . . . because our local chambers of commerce come to the National Chamber's annual meeting, vote for a policy on federal economy, and then go to Capitol Hill and ask for a federal project for their area. (2) ... because our mining men ask for a subsidy to mine submarginal deposits that can't be economically mined in a free economy. (3) . . . because 18,000 men and organizations all over the country recently wired or wrote a Congressional committee asking that the Army Engineers be exempt from the President's power to reorganize the Executive Branch of the government under the recommendations of the Hoover Commission.

Jan 1, 1949

By Charles Will Wright

The application of the camera as an adjunct to topographic mapping began practically with its invention, and it has been employed with varying success since that time. With the exception of the camera to be described, the plate-camera has been universally used in this work, thus giving a projection of the area photographed on a flat surface. From such projections or photographs, by the rules of geometry and of perspective, points defining topographic features and seen from at least two camera-stations may be projected upon a ground-plane—the map.' In 1904 I employed the plate-camera for this purpose in Alaska, but found that the labor necessary to plot the maps, even in a general way, was long and tedious. In 1905 a small Eastman panoramic camera was fitted with spirit-levels, a sight-alidade and a transparent scale, introduced inside the camera to register the degree-points in the sky-line of the film-negative ; also, arrows to indicate the horizon-line. This was, on the whole, successful; but the details in the topography were not brought out in the views with sufficient clearness, aid the photographs were too small. These difficulties were overcome by obtaining a larger and more carefully constructed instrument, which was satisfactorily employed in the field during the year 1906. A panoramic view is made up of an integral number of perspective views upon flat surfaces, and logically is the most accurate and direct means to obtain an impression of a field of * Published by permission of the Director of the U. S. Geological Survey. Stanley, H. M. Photographic and Co-ordinate Surveying, Bans., xx., 740 to 766 (1891). Also, Flemer, J. ,4. Phototopographic Methods and Instruments, Report U. 8. Coast and Geodetic Survey, pt. 2, app. 10, pp. 619 to 735 (1897).

Jan 1, 1908

By J. Burns Read

IT IS the purpose of this paper to summarize, as far as possible, the metallurgical information and experience gained by the Ordnance Department, during the War, in the manufacture of artillery cartridge cases, to describe the tests to which artillery cartridge cases were put, and to summarize the knowledge and experience gained in this testing. The authors wish to acknowledge the aid given by manufacturers, army officers, and civilian employees of the Ordnance Department in obtaining these data. Artillery cartridge cases are cold drawn from circular disks punched from strips of rolled brass. The manufacture involves from 25 to 30 main operations, which are done almost entirely on a punch press. Descriptions of the operations have appeared in various periodicals and, therefore, will not be given here. After each cupping, or drawing, operation, except the last, the cases are annealed at from 540° to 650° C. (1000° to 1200°F.), to remove all the hardening stresses set up in the metal and to allow complete recrystallization. After each annealing, the cases are pickled in niter cake or sulfuric-acid solution and then washed in water to remove all traces of acid. In some instances, the cases are then immersed in a cyanide-salt solution, and afterwards rinsed in water, to remove the thin layer of copper that forms on the surface of the cases during the acid pickle. The last cold-drawing operation is followed, by the heading operation which, by flattening the head of the case on the outside, causes the metal to flow on the inside to approximately the proper finished dimensions. The mouth, or open end, is then annealed at 430° to 480° C. (800° to 900° F.) by immersion in a salt bath or by gas flames. After being washed, the cases are tapered, when they are ready for machining, inspection, and testing.

Jan 4, 1922

By R. E. Heithecker

Almost every oil well drilled into limestone formations in Kansas is treated with hydrochloric (muriatic) acid upon completion: to increase potential capacity of well and thereby increase its "daily allowable" production; to shorten time required to produce recoverable oil; and to increase quantity of oil recovered ultimately from reservoir. Acid treating marked a forward step in the producing fields of Kansas; in fact, many old limestone fields that almost had reached their economic producing limit were "rejuvenated" with acid and their capacities to produce increased several times. It also caused a marked increase in the ultimate oil recovery of some old and nearly depleted fields of Kansas. The effect of the acid was due to the cleaning-out action by the acid at the face of the limestone, the enlargement of the small drainage channels, and the apparent penetration of the acid to previously undrained porous and saturated strata. Studies of the effects of acid were made in the Fairport field, three groups of wells in the El Dorado field and the Shutts field. Estimation of increased recoveries resulting from acid in these fields and groups of wells ranged from 1000 to 2400 bbI. per acre. Limestone structures that had been tested by drilling and found noncommercial were later completed as commerical oil-producing formations through the use of acid. The Kansas City formation, Valley Center field of Kansas, is an example. Increased oil production and revenue from the old fields justified the reconditioning of equipment, which in most cases had become in poor mechanical condition. The first treatment with hydrochloric acid of an oil well in Kansas was in October 1932, and by the end of 1937 almost 6000 wells had been treated. Many wells were treated more than once and the total number of treatments exceeded 8000 by the end of 1937. Approximately 12 3/4 million gallons of acid was required for these treatments. The report includes 15 illustrations and 16 tables.

Jan 1, 1939

By R. E. Heithecker

Almost every oil well drilled into limestone formations in Kansas is treated with hydrochloric (muriatic) acid upon completion: to increase potential capacity of well and thereby increase its "daily allowable" production; to shorten time required to produce recoverable oil; and to increase quantity of oil recovered ultimately from reservoir. Acid treating marked a forward step in the producing fields of Kansas; in fact, many old limestone fields that almost had reached their economic producing limit were "rejuvenated" with acid and their capacities to produce increased several times. It also caused a marked increase in the ultimate oil recovery of some old and nearly depleted fields of Kansas. The effect of the acid was due to the cleaning-out action by the acid at the face of the limestone, the enlargement of the small drainage channels, and the apparent penetration of the acid to previously undrained porous and saturated strata. Studies of the effects of acid were made in the Fairport field, three groups of wells in the El Dorado field and the Shutts field. Estimation of increased recoveries resulting from acid in these fields and groups of wells ranged from 1000 to 2400 bbI. per acre. Limestone structures that had been tested by drilling and found noncommercial were later completed as commerical oil-producing formations through the use of acid. The Kansas City formation, Valley Center field of Kansas, is an example. Increased oil production and revenue from the old fields justified the reconditioning of equipment, which in most cases had become in poor mechanical condition. The first treatment with hydrochloric acid of an oil well in Kansas was in October 1932, and by the end of 1937 almost 6000 wells had been treated. Many wells were treated more than once and the total number of treatments exceeded 8000 by the end of 1937. Approximately 12 3/4 million gallons of acid was required for these treatments. The report includes 15 illustrations and 16 tables.

Jan 1, 1939

F. E. Bachman, Port Henry, N. T. (communication to the Secretary*):—In discussing Mr. o.o.Laudig's paper, the Action of Blast-Furnace Gases Upon Various Iron-Ores,' I took the ground that Mesabi-ore explosions were entirely mechanical; but more observation and later experience has caused me to

Jan 1, 1905

By Robert S. Nichols

Fording Coal Limited's mine in the Rocky Mountains near Elkford, B.C. has produced 21.8 million clean tonnes of metallurgical coal from 1971 to 1980, inclusive. This production has come from several pit areas and required the removal of 149.1 million bank cubic meters of waste rock and overburden by truck-shovel and dragline operations. Waste dumps from 30m to 200m in height have been successfully constructed on natural slopes, generally between 10° and 26°. Design considerations for the dumps include foundation and soil conditions, natural slope angles and containment of weak overburden or rehandle materials. Dump control is maintained by monitoring the crest and the face of an active dump area. Crest movement is measured by extensometers locally termed "Spoil Monitors". When crest movement rates progressively increase above normal, dumping operations are temporarily relocated. Some unstable conditions and mass failures have occurred as the result of natural foundation slopes being in excess of 26°, failure of weak water saturated foundation soils or weak material being placed on the dump.

Jan 1, 1983

By Arthur Forsyth

A SEARCH through the available literature shows that the cobalt-nickel-silicon system has not been systematically studied. This seems rather odd because all three elements are fairly abundant and have better than average corrosion resistance; however, they have high melting points, which makes experimental work difficult. Cobalt and nickel form a continuous series of solid solutions and each metal dissolves about 7.5 per cent silicon. Many ternary alloys have been studied and the results have been published in a great many different ways, but to present such data in a short but clear and understandable manner is still a problem. The following pages describe the results of the study of 76 alloys from which the partial ternary diagram (Fig. 1) of the cobalt-nickel-silicon system has been drawn. The alloys were chosen according to the plan in Fig. la by taking definite ratios of cobalt and nickel, such as 70 Ni, 30 Co or 40 Ni, 60 Co, and adding silicon in various percentages. Each section was studied in detail by means of thermal analysis and microscopic examination, but only two of these detailed sections were thought necessary in the point perspective drawing to give a comprehensive picture of the liquidus, solidus and solid transformations that take place over the temperature ranges studied. Complete thermal analyses and microscopic data are given in Table 1.

Jan 1, 1940

By Samuel Hoyt

THE writer has long been interested in seeking an explanation of the upper heat effect in the copper-tin alloys over the a + ß range, first described in 1913. These notes are offered, not at all as the final explanation of this heat effect, but rather to indicate certain progress which has been made toward establishing what happens over this temperature interval. While working on the thermal analysis of the copper-rich kalchoids (copper-tin-zinc alloys), it was noted that those alloys containing major portions of tin and minor portions of zinc exhibited two marked heat effects, one at about 520° C. and the other at about 600° C., instead of the single effect which is generally observed in either of the two binary series. This matter was discussed with Dr. Guertler, who suggested that a heat effect at about 600° C. in the pure copper-tin alloys might be expected. This led to a more searching examination of the thermal critical points in the pure copper-tin alloys, with the result that a marked, although somewhat weak, heat effect was located at about 600°. Somewhat later, this upper heat effect was discussed with Dr. Burgess, and it was requested that the Bureau of Standards make heating and cooling curves of one of these alloys for the purpose of removing any possible doubt as to the actual presence of the heat effect. Results obtained by the Bureau are given in Plate I. In an earlier paper1 differential curves were published showing that the heat effect occurred at constant temperature over the a + ß range and increased in magnitude with the amount of a up to a point somewhat above 20 per cent. tin. No heat effect was noticed at this temperature in the eutectoid alloy. The existence of this heat effect seems to require a modification of the present copper-tin diagram in the a + ß field, and it has been the object of the work here presented to secure the evidence upon which such a change should be based.

Jan 12, 1918