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By W. L. Dennen, W. W. Wirth

Research looking toward the reduction of the cost of roof support by substitution of longer-life materials for wooden timber is fully justified by the fact that roof support is an important element of all production costs. Permanent or semipermanent roof support will reduce the expense of timber-maintenance crews during steady operations, but even more markedly during idle periods. The management, therefore, is faced with the important problem of timber renewals, which in times of regular operation are frequently obscured by more urgent problems of production. Increased use of timber in the Anthracite Region of Pennsylvania is caused mainly by increased percentage of coal obtained from robbing areas, which requires more timber for safety than development work, and maintenance of long haulageways through crushed ground despite the fact that less coal is transported over them. The timber reserve in the immediate vicinity of the mines has been depleted to such an extent that it is necessary to secure 70 per cent of the timber requirements from distant sources. Originally, mine timbering in this region was done by largely utilizing round props or legs with round collars. The whole cross section of the tree from which timber was cut was utilized by forming the joints between the legs and the collars with saw and adze, using plank or round saplings for lagging behind the legs and over the collars to prevent material falling between them. The Mine Inspectors' report of 1898 records an important digression from the use of round timber, when two tunnels at the Babylon colliery, near Pittston, Pa., were timbered with 12 by 12-in. square timber sets with mud sills, through quicksand for distances of 425 and 160 ft., respectively. The timbers were lagged with 3-in. plank to control sand. An early step toward the permanent type of roof support was the installation of "brick pillars or perfect arched brick rooms" instead of

Jan 1, 1940

By W. L. Dennen, W. W. Wirth

Research looking toward the reduction of the cost of roof support by substitution of longer-life materials for wooden timber is fully justified by the fact that roof support is an important element of all production costs. Permanent or semipermanent roof support will reduce the expense of timber-maintenance crews during steady operations, but even more markedly during idle periods. The management, therefore, is faced with the important problem of timber renewals, which in times of regular operation are frequently obscured by more urgent problems of production. Increased use of timber in the Anthracite Region of Pennsylvania is caused mainly by increased percentage of coal obtained from robbing areas, which requires more timber for safety than development work, and maintenance of long haulageways through crushed ground despite the fact that less coal is transported over them. The timber reserve in the immediate vicinity of the mines has been depleted to such an extent that it is necessary to secure 70 per cent of the timber requirements from distant sources. Originally, mine timbering in this region was done by largely utilizing round props or legs with round collars. The whole cross section of the tree from which timber was cut was utilized by forming the joints between the legs and the collars with saw and adze, using plank or round saplings for lagging behind the legs and over the collars to prevent material falling between them. The Mine Inspectors' report of 1898 records an important digression from the use of round timber, when two tunnels at the Babylon colliery, near Pittston, Pa., were timbered with 12 by 12-in. square timber sets with mud sills, through quicksand for distances of 425 and 160 ft., respectively. The timbers were lagged with 3-in. plank to control sand. An early step toward the permanent type of roof support was the installation of "brick pillars or perfect arched brick rooms" instead of

Jan 1, 1940

By H. H. Kellogg

Available high-fernperatzwe equilibrium measurements and other thermochernical data have been critically reciewed for sulfation reactions of the type: Recommended values for log K and ?Fo as junctions of temperature are given for thirty-six suck reactions involving twenty-six different metals. Methods of calculation and choice between conflict-ing data are discussed. SELECTIVE sulfation now enjoys a considerable renaissance as a metallurgical unit process due, in large part, to the available of the fluid-bed re- actor—a device capable of the close control of temperature and gas composition necessary for a successful sulfation process. An additional need, however, if sulfation chemistry is to be approached in a scientific manner, is a reliable body of data on the equilibrium and kinetics of sulfation reactions in simple and complex systems. This paper offers a critical review and compilation of equilibrium data on pure sulfates (simple systems). The last such review, by K. K. Kelley in 1935:30 has proven itself most useful, but the existence of many new data makes necessary a re-evaluation of the available information. METHODS OF CALCULATION For a simple sulfation reaction such as MS04(c) = MO(c) + SO3 [1] there are two approaches one may take toward establishing the value of ?Fo or K as a function of

Jan 1, 1964

By Henry M. Howe

This paper may be regarded as a report of progress of an investigation into the influence of prior exposure to different high temperatures, under different conditions, on the properties of steel after it has been cooled completely. The following are the chief divisions: II.—Experiments on toughening manganese-steel by sudden cooling. III.—A study of the critical points of common or carbon-steel, chiefly by examining the spontaneous retardations which occur in heating and cooling it, and by examining the ductility of pieces of steel which have been cooled suddenly from different temperatures by quenching them in water or brine. IV.—A brief note on Osmond's theory. V.—A study of the critical points by examining the ductility of pieces of steel which have been cooled slowly from different temperatures at, above, and below them. VI.—A description of the furnace used, with notes on thermoelectric pyrometry. It remains to throw further light on the questions studied by ascertaining the condition of the carbon and the hardness proper, and by studying the microstructure and the fracture of the many pieces treated. I hope to present later the results of experiments in some of these directions. With few exceptions, the experiments have been performed in my private laboratory. I tender sincere thanks to my assistant, Mr. William Haskins, S.B., on whom most of the labor has fallen, for his zealous and intelligent co-operation; to the Sterling Steel Co. for their extra hard steel, Series 17; and to Mr. Joseph Hartshorne and the Pottstown Iron Co. for their soft basic steel. Series 8, 9,10, and 18 were supplied by Messrs. Spaulding, Jennings & Co., of the West Bergen Steel Works; to them also my thanks are due. The temperature of the pieces treated has been very carefully

Jan 1, 1894

By Ancel St. John

DURING a session on coal and coke at the February, 1926, meeting of the American Institute of Mining and Metallurgical Engineers, the writer called attention to the important work on the X-ray analysis of coal1,2 being carried on in England by C. Norman Kemp and his associates. This aroused so much interest that a paper on the subject was requested for the October meeting. It has seemed advisable to make this paper a preliminary survey of the present status in the application of X-ray methods to coal problems and to follow it from time to time with further articles as the art develops. A survey of this sort naturally divides itself into two parts, radioscopic analysis of the distribution of constituents through the body of the coal, and diffraction analysis of the state of association of the elementary components. In this article the subject matter concerning radioscopic analysis has been drawn almost entirely from the writings of Kemp and his associates and the illustrations have been specially furnished by him. It is a pleasure to record here a great indebtedness for this courtesy and cooperation. The subject matter and illustrations concerning diffraction analysis are taken from the author's unpublished researches.

Jan 10, 1926

By Joseph L. Gillson

In this volume, which is divided into chapters on a commodity basis, many subjects inevitably have a common interest with others, or are interrelated in one way or another. No group of commodities is so outstanding in this regard as is that group of which the basic raw material is a carbonate rock. There are chapters in this book on dimension stone, on crushed stone, on chalk and whiting, on cement, on lime, on magnesite, on sodium carbonate; all of which are entirely, or partly, products of the "carbonate rocks." Rhodochrosite, witherite and strontianite are other carbonates described respectively in chapters on manganese minerals, barium minerals and strontium minerals; and travertine and cave onyx are carbonate materials used as ornamental stones. High grade marble is used for monuments and statues and as a decorative building stone. The aggregate tonnage of the basic raw material, the carbonate rock, is so enormous that it exceeds the tonnage of any metallic ore mined and quarried in the United States, and in turn is exceeded only by coal, sand and gravel, and by water in the gross tonnage produced by the mineral industry in this country. The specialties, including magnesite, sodium carbonate, and rhodochrosite, witherite and strontianite are produced from uncommon rock types of limited occurrence. They are described adequately in the chapters devoted to these subjects. This chapter is concerned with the limestones and dolomites. No other solid rocks are as important as these in the industrial life of the world, nor are any so widely known. Massive units of some carbonate formations form many of the spectacular features of some of the most rugged mountains in the world, such as the Dolomite Alps, the Canadian Rockies, some rugged peaks of the eastern flanks of the American Rockies in Colorado, Wyoming and New Mexico and in many ranges in Utah, Nevada and Arizona. These continue down the Sierra Oriental in Mexico and on around the world to the flanks of the Himalayas, in the South China Highlands, and separating Asia and Europe in the flanks of the Ural Mountains where they form many reexhumed hills called Shikhany.50a Less rugged and more nearly flat-lying carbonate rocks underlie most of the area of our great Middle Western plain, the southern part of England and the northern part of Africa. These are the common rock formations known from boyhood to a large part of the world's population. The use of lime, produced by the burning of limestone, goes back to antiquity, and mortar was used widely in Biblical times. The cement made by mixing volcanic ash with lime was a basic material of construction when Pompeii was built. Our Eastern states are dotted with abandoned limestone quarries, and the ruins of old lime kilns which were operated in Colonial days. Many limestones and dolomites are found in flat-lying strata of a thickness convenient for quarrying as a building stone, so that houses and other structures have been built with them for centuries. In order to replace the muddy and rutted dirt roads with surfaces that could stand the hard usage of his wagons and carts, man learned to crush stone and put a layer of it on his old trails. Such roads built by the Romans have been in use over much of

Jan 1, 1960

By John R. Don

This paper, under the title of "The Genesis of Auriferous Lodes from a Chemical Point of View, Illustrated by Analyses of Samples Taken from the Chief Auriferous Area of New Zealand, Victoria and Queensland, by John R. Don, D.Sc., M.A., Lecturer on Geology in the University of Otago, N. Z.," was submitted by the author with the frank confession that its length, covering several hundred printed pages of the Transactions of the Institute, would preclude its acceptance for publication in full. But the great value of the original work which it records rendered its rejection on that ground highly undesirable ; and, after correspondence with Dr. Don, it was agreed that the Secretary should condense the paper, subject to the author's approval, omitting what was not essentially connected with the original work reported. In the discharge of this laborious and difficult duty, the Secretary's chief trouble has been his regret to cut out the acute criticisms and admirable theoretical and historical summaries of Dr. Don on the general subject of the science of ore-deposits. It should be added, that the original paper has been returned to the author, with full permission to publish it through any other medium (due mention being made of the first publication by the Institute of portions thereof), and a cordial expression of the hope that the treatise, as a whole, may be thus published, to the advantage of science. The Secretary begs to add, that many of the portions necessarily omitted from this condensed version would constitute, in his judgment, interesting and valuable separate contributions. In attempting to condense this paper, it was necessary at the outset to cut out the tint three chapters, of which the following brief outline is therefore given. Chapter I., introductory in character, indicates the importance of chemical analysis in the investigation of the genesis of ore-deposits, emphasizing the value of Prof. Posepny's Institute paper, and especially of the discussion which it aroused, and stating in general terms the theories of "lateral secretion" and "ascension." Chapter 11. describes the scope of the investigation undertaken by the author, the chief purpose of which was to determine which of the above-named theories was favored by the evidence obtained. This evidence consists chiefly (though not wholly) of analyses of the country-rock taken at various distances from the auriferous "reefs," (a) on deep mine-levels; (b) in the surface or "vadose" region : and also (c) of underlying, neighboring or connected crystallines (granite, gneiss, etc.). In addition to these investigations, there is a separate inquiry into the question of the deposition of gold in marine basins, suggested by the fact that most of the gold in the lodes of Australasia occurs in stratified deposits. Chapter 111. discusses the principles and methods followed by the author in the examination of country-rock for the purpose described. After giving his reasons for believing that careful tests of carefully-chosen samples of country-rock taken at varying distances from the ore-deposit might throw light upon the question

Jan 1, 1898

By J. M. Flaitz, A. S. Parks

OF the various methods of sampling gas-condensate wells, a method that secures a continuous representative sample of the well stream is desirable. Such a method, consisting of a sampling tube introduced into the well tubing, has proved satisfactory. The method is sufficiently accurate for operating and engineering problems. A portable testing apparatus can be used with the sampling tube to obtain data useful in studying the economic and technical aspects of the development and operation of gas-condensate properties. INTRODUCTION The recent discovery and development of gas reserves that contain hydrocarbons that condense with reduction of temperature or pressure, or both, to form a product known as condensate, has brought many new problems to the oil and gas industries. With further discovery of deep, high-pressure fields it is presumable that many more gas fields of this type will be added to the steadily increasing number. Such gas reserves are found either associated with oil as a gas cap or in separate formations. There seems to be no positive correlation between the physical or geological nature of the reservoir, and the chemical composition or phase characteristics of its contents. Knowledge of the chemical make-up and phase behavior of gas-condensate reserves are needed to cope with many problems. A knowledge of the chemical composition and phase characteristics of the reservoir material is necessary to properly design a gasoline or recycling plant, to estimate natural gas and condensate reserves, to enable the operator to study the economic and technical aspects of various methods of operation and development, and to carry out the plan of operating subsurface and surface lease equipment. This information is often useful in questions of mineral ownership, proration, legal position, and taxation. It is the purpose of this paper to discuss methods used by the writers to determine the chemical composition and phase characteristics of the fluids produced from a condensate well. The scope of the paper includes a discussion and description of the method of sampling, the results of tests on the accuracy of the sampling method, a description of a portable testing apparatus used to examine the phase characteristics, typical results of tests on wells from several condensate fields, and some of the applications of these data to production problems. References to previous work on this subject are cited at the end of the paper. THE PROBLEM At reservoir conditions of temperature and pressure, the fluids produced from a condensate well exist in a homogeneous vaporous condition. The consequent reduction of temperature and pressure that occurs as this gas enters and flows up the well tube results in condensation of some of the hydrocarbon material to form a liquid. The relative amount of liquid condensed at any point in the flowing system

Jan 1, 1941

By R. S. Archer

THE binary aluminum-silicon alloys have certain characteristic advantages which are now well known, and these alloys have come into considerable use during the past several years.1 Their field of application has been limited to a certain extent, however, by their low yield point and hardness, low endurance limit, and relatively poor machining characteristics. These properties are improved by the addition of copper, and the ternary aluminum-silicon-copper alloys constitute an important class. The addition of copper decreases the corrosion resistance of the aluminum-silicon alloys and increases specific gravity. Magnesium is a hardening addition which seems to have relatively little effect on corrosion resistance, and which, of course, reduces specific gravity. The object of the work described in this paper was the development of alloys and heat treatments for the production of sand castings and permanent-mold castings having substantially all the advantages of the binary aluminum-silicon alloys together with mechanical properties improved to a degree permitting wider application.

Jan 1, 1930

By William H. Emmons

CONTENTS. [ ]

Jan 1, 1913

By Henry J. Miller, Marcella Linderman

During some experiments made by Henry J. Miller, partly in Germany and partly in the United States, in which it was found necessary to melt metals in quantities up to 60 kg. in a vacuum or under low pressures of hydrogen, molybdenum was tried as the resistor in the electric melting furnaces. Molybdenum ribbons 16 by 0.55 mm. and 18 by 0.45 mm. were used as resistors. The furnaces were of the type shown in Fig. 1. About the heating tube, Y, are wound parallel resistors of molybdenum ribbon from the water-cooled electrodes, El, Ez. The whole is within a copper container having outlets for the removal or introduction of gases and a window, W, for observation, the space about the heating tube and electrodes being filled with insulating material. The life of the molybdenum used as the resistor was found to depend very much on the manner of using it, its failure being due in some cases to thinning by evaporation or chemical reaction and in others to hardening, which prevented it from following the expansions and shrinking of the heating tubing without cracking. As such failures are often rather expensive in commercial work, it was thought worth while to determine the causes. The factors influencing the behavior of molybdenum resistors used in this manner may be briefly stated as follows:

By K. Huessener

This paper attempts a survey of the principles involved in the combustion of blast-furnace gas in boilers and stoves. I do not expect to be able to give much information which is actually new, since the laws and methods of calculation pertaining to this problem are contained in a number of handbooks; but, so far as I am aware, they have nowhere been treated exclusively with reference to this one problem of gas economy. The road which I follow is less that of strictly scientific research than that of the practical engineer, faced by operation problems which require a quick solution by easily accessible means without a prolonged search in scientific handbooks. For this purpose I give a number of tables and diagrams, as well as the results of many years1 practical working experience as combustion engineer, which I trust will prove useful to my readers. HlSTORICAL Considering the tremendous efforts made during the last 15 years to increase the efficiency of all kinds of power plants, it is highly surprising that until a comparatively very recent period, progress in the economical combustion of blast-furnace gas has been so slow, The explanation generally put forth, that fuel has been so cheap that it was hardly worth while to bother about this economy, will not hold good, for the greatest trouble was taken to improve the combustion of coal and to reduce the consumption of steam, The most plausible explanation appears to be the general impression, held as an accepted fact, that gas, especially hot, uncleaned, blast-furnace gas, was not a good boiler fuel. Many managers of high repute had tried unsuccessfully to improve the conditions of its use, and the dictum went forth that efficiencies of over 60 per cent., particularly with high loads, were impossible. This was the situation not only in the United States, with very cheap fuel, but also in Europe, where fuel prices are twice and three times as high.

Jan 1, 1916

By John Burns

THE object of this chapter is to present data concerning the effect of the introduction of relatively slight amounts of carbon and nitrogen into supersaturated solution in iron. The study is confined to the alpha temperature range of both the Fe-C and Fe-N systems. The age-harden-ing characteristics of these two systems are considered. These data are compared to those of other age-hardening alloy systems and a "classifica-tion" is essayed. A.-RELATION OF LATTICE PARAMETER AND ELECTRICAL CONDUCTIVITY TO CHANGES IN PHYSICAL PROPERTIES DUE TO AGING OF FE-C ALLOYS Since Whiteley1 in 1927 showed that some of the iron carbide that is normally present in slowly cooled low carbon-iron alloys disappears on rapid cooling from just below the A1 point, interest has been manifested in the possibilities of age-hardening in these alloys. Masing and Koch,2 and at the same time and independently, W. Koster,3 proved these alloys to be age-hardenable. A. A. Bates4 a little later also published an interesting paper on changes in physical properties due to the aging of low-carbon steels. Many other papers have appeared showing changes in physical properties in specific instances due to this same phenomenon.

Jan 1, 1934

By W. L. Fink, R. S. Archer

THIS paper describes results obtained on aluminum-beryllium alloys and aluminum-beryllium-copper alloys in the preparation of which aluminum of 99.95 per cent. purity was used. The constitution and structure of the high purity binary alloys are given. The aluminum-beryllium eutectic occurs at 0.87 per cent. beryllium and 645° C. The solid solubility of beryllium in aluminum at 631° C. is 0.05 per cent. beryllium, and at room temperature is less than 0.013 per cent. beryllium. The densities of the alloys are substantially the same as the values calculated on the assumption that the densities of the elements are not changed by alloying. All of the alloys age-harden at room temperature after a solution heat treatment, and the chill cast aluminum-beryllium-copper alloys age-harden at room temperature without a prior solution heat treatment. Hardness and tensile properties are given. Salt spray corrosion tests on sheet specimens are described. It is shown that beryllium does not lower the corrosion resistance of aluminum to salt spray provided the alloy has received a solution heat treatment. COMMERCIAL POSSIBILITIES OF BERYLLIUM ALLOYS Beryllium has certain properties such as low density, high hardness, good corrosion resistance, low thermal expansion and fairly good electrical conductivity, which would indicate that it is worthy of consideration as an ingredient of light alloys. It was not until recently, however, that beryllium could be produced with sufficient ease to encourage research along this line. The production of beryllium by electrolysis from a fluoride bath has now developed to the stage where it could be used commercially if there were sufficient demand for the element. Claims made in certain newspapers and technical articles in regard to the strength and corrosion resistance of the aluminum-beryllium alloys are not justified by experimental results. Moreover, beryllium is an expensive metal ($200 a pound at the time this work was done) and, on account of the nature of its ore and the consequent difficulty of its extraction, it will in all probability continue to be a relatively expensive metal, although the cost would undoubtedly be a great deal less than $200 a

Jan 1, 1928

By Arthur F. Wendt

Introduction.—In the year 1885, the writer signed a contract to take charge of the reopening and developing of the celebrated old mines of " El Cerro Rico de Potosi." Two years earlier, an Eng- . lish firm of engineers had made a very glowing report on the property. In the summer of 1885, telegrams arrived from the parties in charge of operations at the mountain, claiming the finding of one of the old veins, with an average richness of over 200 ounces to the ton. In the fall of 1886, the author first personally visited Potosi, but found neither the English report nor the telegram borne out by the facts. After an expenditure of over half a million of dollars and more than three years of continuons hard work, the writer succeeded in unwatering and developing one of the principal old veins of the mountain. This vein, called "Cotamitos," now yields ores of about 75 ounces to the ton, and the old historic mountains of Potosi may be said to have again fairly entered the list of silver-producers. The experience of the author, during his residence in Bolivia, and data obtained from Sr. Don F. Avelino Aramayo, form the basis of this description. POTOSI. Etymology of the Name.—The Quichuá (pronounced Keechna) Indians, known to North American students as the " Incas," although the word "inca" merely signifies ''king," or "chief," of the Quichuás, called the mountain "Sumac-orcko," or the beautiful mountain." Eighty-three years before the discovery of the mountain by the Spaniards, the inca, or king, Huaina Ccapac, travelling from Cantumarca to Calque-Porco, saw the mountain of Potosf and, admiring its grandeur and beauty, said that within its bowels there was, no doubt, much silver. He ordered his vassal* to work the mines. They, having carried their mining implements to the mountain, ascended it and were on the point of commencing work, when they heard a voice of thunder, which said: " Do not take

Jan 1, 1891

By G. Sachs

X-RAY analysis and single-crystal study have been utilized in recent years as a new means of following constitutional changes in alloys. If such transformations can be suppressed by rapid cooling, they can be followed at room temperature in a particularly convenient manner. In the following we shall consider changes in solubility and polymorphic transformations with particular reference to phenomena of the age-hardening type. Finally a thermodynamic viewpoint is developed for examining such transformations.

Jan 1, 1931

By E. W. Engle

For several years the Fansteel Products Co. has been engaged in e production and development of various of the rarer metals. It is at present engaged in the commercial production of tantalum, tungsten, and molybdenum in a very high state of purity. The information contained in this paper is partly a general compilation from various sources and partly information obtained as a result of recent years of work in the laboratory of this company. Tantalum, tungsten, and molybdenum form a group peculiar to themselves among the commercially available metals. Their very high melting points (tantalum 2770' C., tungsten 3350' C., and molybdenum 2550" C.) set them apart so far as the metallurgical processes for their production are concerned. Further, when properly prepared and treated they will stand a somewhat unusual degree of cold work, that is work below the temperature at which marked crystal growth takes place. Such cold-worked metal may show a high tensile strength; tantalum to 130,000 lb. per sq. in., tungsten to 490,000 lb., and molybdenum to 260,000 lb., in the form of fine wire. In physical appearance, these metals are not unlike some steels; they may be better described by saying that polished tantalum somewhat resembles lead; polished tungsten, iron; and polished molybdenum, nickel. The polished surfaces of all three remain untarnished in ordinary air. Air containing corrosion-producing impurities will, in general, show molybdenum the least resistant to corrosion and tantalum the most resistant. Molybdenum has, however, a high degree of resistance to corrosion by hydrochloric acid, a property that should render it of commercial interest. On the other hand, it is markedly attacked by some of the weaker organic acids. The three metals oxidize rapidly when heated at or above a dull red in air. This feature limits their use in many applications where their high melting point and strength make them appear usable. Tungsten and molybdenum, at red heat, are quite inert to hydrogen and nitrogen; while tantalum has a rather remarkable affinity for all the ordinary gases, which results in its becoming embrittled in their presence. This

Jan 1, 1925

By Robert Keeney

THE electric smelting of manganese ore and the production of ferro- manganese did not exist as an industry, in the United States or elsewhere, previous to the outbreak of war in 1914. Ferromanganese had been produced, electrically, during times of high prices by two companies at Niagara Falls and by several European companies, but the production. was spasmodic, and none was electrically produced when ferromanganese sold at from $35 to $40 per ton. Thus the electric smelting of manganese ore must be considered as a development caused by the high prices prevailing during the years 1916, 1917 and 1918, and the necessity of smelting domestic ore in order to fill the ferromanganese requirements of the steel industry of the United States, which increased from 189,088 tons in 1914 to 356,356 tons in 1918. The electric furnace is well adapted to smelting domestic-ore because it can be located in small units near the source of ore supply. In 1918, the ferromanganese production of the United States was 333,027 tons, of which about 7 per cent., or 23,000 tons, was produced in the electric furnace. The electric furnace not only assisted materially in the development of a domestic-ore supply but made a considerable saving of coke, as it requires about 1,4 tons of bituminous or lignite coal per ton of ferromanganese compared with a blast-furnace consumption of 2.9 tons of coke per ton of ferromanganese. Some of the plants in the United States that smelted manganese ore in the electric furnace during the war and in 1920 are listed in Tabled. From early in 1919 to about February, 1920, little ferromanganese was produced in the electric furnace. During this period the price of ferro-manganese (78 to 82 per cent. manganese) was about $100 per ton. During the first half of 1920, several plants resumed operation when the, price of. ferromanganese (76 to 80 per cent. grade) gradually increased to $200 per ton, delivered.

Jan 2, 1921

By G. Ansel, J. P. Doan

THE important literature concerning zirconium in magnesium-base alloys is predominantly contained in patent references. Sauerwald, Eisenreich, and Holub1-4 discovered the profound grain-refining influence of small amounts of zirconium on cast magnesium and the attendant increases in strength, and ductility. They extended their work to reveal that limited amounts of certain other elements, including zinc, could be added for further improvement in strength and hardness. British. Patent 5111376 relates to the parent discoveries of Sauerwald, Eisen¬reich, and Holub. All of these references deal primarily with casting characteristics and properties in the cast state. Minor mention is made of desirable tensile strength, ductility, and toughness of wrought Mg-Zr alloys* modified by one or more additional elements. No extensive reference in the literature" has been found to the particular characteristics of wrought Mg-Zn-Zr alloys, with which the present paper is concerned. - The work to be discussed represents essentially an extrusion study of the Mg-Zn-Zr alloys and indicates that this system is highly interesting in the wrought state both academically and commercially. Accordingly, an important aim of this paper is to describe the hot-workability, tension and compression properties, metal¬lography, and toughness of these alloys. Compositional variations are limited to the ranges o to 7 per cent Zn and o to I per cent Zr. EXPERIMENTAL PROCEDURE Alloying and Casting Alloying ingredients were cell mag¬nesium, commercial zinc (intermediate grade), and a chloride salt containing approximately 50 per cent ZrCl2 and 50 per cent alkali chlorides. This salt is produced by Titanium Alloy Manu¬facturing Company. Melting, alloying, and pouring procedure essentially followed the crucible process as described by Nelson.6 The magnesium was melted using Dow No. 310 flux, and the temperature raised to 1350° to 1400°F for the alloying operations. After alloying of the zinc, the zirconium containing salt was added in small portions with vigorous stirring. This is an adaptation of the method described in British Patent 533264.7 The alloying efficiency of zir¬conium was approximately 30 per cent. During the alloying of zirconium, fluorspar was added in amount required as a flux¬inspissating agent. Next the melt was refined with Dow No. 310 flux and held quietly for 15 min. Finally billets were cast in a book-type permanent mold

Jan 1, 1946

By T. D. Yensen

IN the investigation of the magnetic properties of iron-nickel alloys,1 it was found necessary in order to make the alloys forgeable, or malleable, to add small quantities of some other element. Iron-nickel alloys have been known for nearly a century, but have been made in commercial quantities only since 1885. Their remarkable mechanical properties were disclosed by Riley in 1889 and from that time on a large amount of research work has been done both to discover new properties and to correlate the results obtained.2 Lately the Bureau of Standards has collected the published data in a special circular3 giving in compact form an account of the properties of the iron-nickel alloys. It also contains a clear historical sketch of the development as well as a selected bibliography. The chief difficulty with the development of iron-nickel alloys was that the "pure" alloys do not forge readily. The addition of small amounts of manganese, however, made the alloys forgeable, and manganese has therefore come to be regarded as a necessary constituent of nickel steels. The present paper shows to what extent manganese is needed for various nickel contents and also what is the effect of other alloying elements on the forgeability. It also touches upon the cause of forgeability but refers to other sources for more exhaustive treatises, on the subject. The alloys were prepared by melting electrolytic iron and electrolytic nickel with of without other alloying elements in the desired proportions in a magnesia crucible in a vacuum furnace under a. pressure of 1 mm. mercury. The ingots weighing about 2 kg. were allowed to cool in vacuo. If pipes or blowholes were present, the ingots were cut in such

Jan 1, 1920