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By D. I. Bardos, F. X. Spiegel, R. K. Malik, Paul A. Beck

Study of the occurrence of elongated ß-Mn phase fields and of their direction of extension in fifteen ternary systems indicates that the ß-,mn phases formed by manganese with other transition elements and with either silicon, germanium, or tin may be considered as electron phases. In these phases the alloying behavior of silicon on the one hand and of germanium and tin on the other shows a significant difference . Formally all observations can be satisfactorily described by attributing to germanium and tin an apparent electron concentration of nine electrons per atom. This behavior may be interpreted by assuming that germanium and tin exclude itinerant electvons because of a strong repulsive potential arising fromthe requirement that their wave junctions be orthogonal to those of- the closed d shells of these atoms. The absence of a d shell in silicon allows this atom to admit itinerant d electrons. The following new ternary phases of unknown structure were identified by means of their X-vay difjraction patterns: (Mn,Co,Si)I , (Mn,Co ,Si)Y, (Mn.Co,Si)Q , (Mn ,Ni ,Si)W , and (Mn, Ti ,Si)A. The X-ray data suggest that these phases have large unit cells and that to some extent they may he related structurally to the 0 phase. The a phase and certain other phases formed by transition elements are characterized by their preferred occurrence at a constant electron concentration. AS a result, these "electron phases" have relation to electron concentration. The tendency of the B phase to form elongated phase fields in ternary systems along the directions of constant electron concentration has been previously demonstrated. The occurrence of an elongated 0-Mn phase field in the ternary system Mn-Co-Si was schematically indicated by Cherkashin et al.l0 The present study includes fifteen ternary systems, each containing in addition to manganese a second transition element from the group Ti, V, Cr, Fe, Co, Ni and one of the nontransition elements silicon, germanium, or tin. In each system the boundaries of the B-Mn phase were determined in the 900°, 950°, or 1000°C isothermal section, the temperature being dictated on the one hand by the requirement of sufficient rates of diffusion to approach equilibrium conditions in reasonably short annealing periods and on the other hand by the need to avoid as much as possible the partial melting of alloys during annealing.

Jan 1, 1967

Jan 1, 1920

By Willard P. Ward

Having been engaged during the past year in the manufacture of ferro-manganese in a blast furnace, I have imagined that some further information on this subject might be of interest to that large number of members of the Institute who are engaged in the iron and steel industries. The great question of the economical production of good steel, ingot metal, or homogeneous iron (we scarcely know now what to call it) from good materials, and at reasonable prices, has, thanks to the intelligence and energy of a few American engineers, been successfully solved in this country. Nearly all first-class railroads, and many that would not rank so high, have adopted the Bessemer rail. Martin boiler-plates are rapidly gaining ground, in competition with

By V. F. Swanson

At the AIME meeting in Tampa in Oct. 1966, an empirically developed equation was presented which allowed the calculation of free settling velocity for any sized particle: 1 [ ] This equation requires the use of two parameters a and p which are coefficients derived from boundary layer theory.2 It was possible to develop values of a and p for several minerals by back calculation of published data. The original equation had one major flaw. When the fluid density exceeds the density of the solids, the solution to the equation becomes imaginary. A flaw was indicated also by the fact that galena and sylvite both having cubic cleavage, did not have similar values for a and b. Galena gave calculated values of a = 1.082 and g = 3.11, while sylvite gave values of a = 1.870 and p = 2.56. These flaws prompted further study of the equation, resulting in the following empirical modification: [ ] It is obvious a real solution of the equation is possible for all values of ps and p. When PL > PS, V is negative, indicating that the particles will rise against the attraction of gravity. The validity of the modification is borne out by the fact that when values of a and p were back calculated for galena and sylvite using the modified equation, both minerals gave values of a = 1.038 and p = 3.01. With the modification shown in Eq. 2, Newton's friction factor becomes [ ]

Jan 1, 1976

By W. M. Pierce

THE present work has been done in an endeavor to correlate and complete the data on the constitution of alloys of zinc with other common, metals, dealing exclusively, however, with the zinc-rich alloys in which the zinc content is between 90 and 100 per cent. This investigation has included the systems lead-zinc, cadmium-zinc, iron-zinc, copper-zinc, aluminum-zinc, nickel-zinc, manganese-zinc, cobalt-zinc, tin-zinc, and magnesium-zinc. The important ternary system zinc-lead-cadmium and the zinc corners of other ternary systems have been investigated in connection with this work but will not be dealt with here. Zinc does not form a single homogenous zinc-rich solid solution over any considerable range of concentration with any of the metals mentioned. A limited range of solid solubility is said,; by previous investigators, to occur in several cases and certain effects on the properties of zinc are attributed (with varying degrees of consistency among different writers) to the presence of certain other metals dissolved in zinc. The increasing use of rolled zinc and the possibilities offered by zinc as a casting alloy in certain fields have it made essential to determine precisely these equilibrium relationships. In carrying out this .investigation reliance was placed chiefly on two methods, conductivity measurements and microscopic analysis. The first method proved valuable in determining the existence and extent of solid solubility. The second method stands alone as a means of determining structural characteristics and supplements the first method in the measurement of solid solubility. The scleroscopic hardness of all conductivity specimens was measured partly for its value from the point of view of mechanical properties and partly; as a check on the conductivity curves in indicating the limits of solid solubility. No hardness curves are included in this paper, for in no case were they important in arriving at the constitution of any system.

Jan 2, 1922

By Alfred F. Brainerd

A few months since, Prof. Lawrence C. Johnson, of the U. 8. Survey, discovered in Mississippi large deposits of carbonate iron-ore, geologically located in the Claiborne formation of the Tertiary Epoch. These deposits are not pockets, but continuous layers or beds extending for miles, and can be located with certainty where they have not been removed by erosion. Upon examination, recently made by G. W. West, Birmingham, Ala., the largest deposits and highest grades of ore were found near Enterprise, Lauderdale county, and in Clark county, Miss. These beds measure from 10 to 18 feet in thickness, are superimposed upon a " burr rock," associated with green sand, and dip 30 feet to the mile southeast, at an altitude of 350 feet above sea-level, can be

Jan 1, 1888

THOSE MARKED THUS * ARE MEMBERS, MARKED THUS ?ARE ASSOCIATES. THESE SIGNS DOUBLED INDICATE LIFE MEMBERS AND ASSOCIATES RESPECTIVELY. THE FIGURES AT THE END OF THE ADDRESS INDICATE THE YEAR OF ELECTION. HEAVY-FACED TYPE SIGNIFIES HONORARY MEMBERSHIP. *AARONS, J. BOYD, Vivian Gold Mining Co., Ltd., Harris, West. Australia. '05 *ABADIE, EMILE R., Cons. and Min. Engr., 214 Union Savings Bank Bldg., Oakland, Cal. '76 *ABBOTT, CHARLES W., Min. Engr. Pioche, Nev. ?08 *ABBOTT, JAMES W., Min. Engr: Ploche, Lincoln Co., Nev. '94 *AOTT, ROBERT R., Met. Engr., Peerless Motor Car Co., Cleveland, Ohio. '12 || ARAHAMS, ALEXANDER I., Student.. .67 E. 93rd St., New York, N. Y. '13

Jan 1, 1917

By Kenneth K. Humphreys, F. R. Zachar, A. G. Gilbert

INTRODUCTION by F. R. ZACHAR and A. G. GILBERT Coal producers are not only faced with the problems of mining coal, but must also decide to what extent they can invest capital and what operating and maintenance expense they can afford, after mining, to market their product in sufficient volume and at a reasonable profit. Regardless of whether the operator is contemplating a new operation or merely considering expanding present facilities, market requirements, ability to make a product meeting requirements, probable costs and possible future changes in raw coal or finished product must be considered. In addition, such items as flow sheet, structural designs, storage facilities, etc, must be examined individually and collectively. In estimating preparation costs to meet predetermined market specifications, the operator must calculate the economics of present preparation practices to anticipate the increase to total production which results when the quality of the finished product is increased. The consumers of coal are continually seeking to obtain the best and most adaptable product for their money. Regardless of whether coal is used for coking, industrial requirements, electric power generation, domestic fuel or for other purposes, it will be scrutinized from such standpoints as delivered cost, suitability for utilization in certain equipment, ease of ash disposal, adaptability to material handling system plans and its potential for generating dust problems. Utilities, due to large capacity volume requirements, are generally in a position to select coal that will result in the lowest over-all cost per million Btu. Freight costs, paid by the utility, are important and are given utmost consideration when a coal is under consideration. Steel companies, whether producing or purchasing coking coal, are continually seeking coal that will result in lowering the cost of pig iron production. Since it is usually necessary to clean to lower specific gravities, say 1.40, to turn out a product meeting metallurgical requirements, it follows that a high ash "middling" product is created. These low quality middlings do not command a good price. Therefore, unless the metallurgical coal can command sufficient realization to carry or subsidize the middlings, the operator may be ahead economically to prepare steam coal at a higher specific gravity. While the "unit-train" rate reductions have been helpful to the economy of the coal industry, the establishment of these rates has made mandatory the installation of storage and rapid car loading facilities at mines and plants shipping utility coal (see Chapter 15). A study of the economics

Jan 1, 1968

By F. L. Bosqui

A. L. BlomFIeld, Denver, Col. (communication to the Secretary.*) — Mr. Caldecott says on p. 67: "The Dorr thickener shown, while a useful device when crushing with cyanide solution for removing surplus solution from slime pulp prior to air-lift agitation or vacuum filtration, is not adapted to effect as complete a separation of water from settled slime as the ordinary intermittent settlement and decantation." This statement might have passed muster in this country several years ago when. the Dorr thickener was a new device, but its use in hundreds of mills in the United States has demonstrated that as thick a product is being discharged from it as was obtained from the intermittent settling which it has supplanted. • It is interesting to note that recent investigation, especially the work of 11. 6. Coe and G. H. Cleveilger,' in the March Bulletin of the Institute, under the title: Laboratory Method for Determining the Capacities of Slime Settling Tanks, has developed the general theory of settlement and explains the results obtained in practice. Just as free settlement is a function of surface area, so thickening after the zone of free settlement is passed is a function of time. The time required is obtained by the capacity or volume provided in the settler for this thickening zone. Each pulp is a problem in itself, both in regard to free settlement and to time required to reach a commercially finished thickness. Some pulps require 48 hr. and more to reach a density of 40 per cent. solids; others no coarser to the screen test reach a density of 65 per cent.' solids in a fraction of that time. In thickening any pulp a point is reached where the increase in density is so slow as to be commercially unprofitable. When any part of the pulp has reached this point it should pass on for treatment—its place in the thickener should be occupied by pulp which has not yet reached the commercial limit. By doing this the whole volume of the settling tank is kept in active use. Thus the continuous thickener keeps the whole tank at work to its commercial limit, while the intermittent settler has much of its volume occupied at times by pulp which is either quite finished thickening or at least thickened past the commercial point. The mechanical efficiency of the continuous thickener can be the only argument for limiting this statement. In my own experience I have never

Jan 1, 1916

By M. G. Corson

Until recently, the characteristics of cast copper have seldom been studied and such study as has been made has been inadequate. The prevailing idea seems to be that since pure copper is infrequently used in the cast stlate, there is no reason for trying to establish precise data regarding the properties of the metal in that condition. On the other hand, wrought copper either in the shape of sheets or wire rarely fails in service, except as a result of the action of reducing gases at the annealing temperatures, so there is little incentive to study the properties of the cast shapes —cakes, bars, ingots and billets—for the sake of tracing the causes of failures of the wrought metal to the cast stock. However, about a decade ago, wirebars of American origin often cracked badly while being hot-rolled in mills in Germany. This Icd to four investigations: by E. Seidl and E. Schieboldll by P. Siebe12 by 0. Bauer and G. Sachs,3 and by G. Welter.4 These authors came to the conclusion that failures in hot-rolling were due essentially to the presence of a wide zone of columnar crystals between t'he thin layer of fine crystal5 near the surfaces of the bars and the large but more nearly equiaxed grains of the central core. This macrostructural defect was explained in turn by the probable upward deviation in the temperature of the metal while it was being poured into the molds of the castling machine. More recently, cast shapes of copper were investigated by X. 1'. Allenh and by C. Blazey. Allen examined vertically cast wirebars and hori-zontally cast wedge cakes of electrolytic tough-pitch copper, but only for the distribution of densities; i.e., porosity. Blazey was interested mainly in the mechanism of the variations in electrical conductivity due to cold-work and anneal, but gave introductively an account of the composi-tion and average densities of the tough-pitch horizontally cast Wirebars used. As far as the present writer can tell, no investigation mas under-taken for the sake of presenting a picture of the distribution of mechanical characteristics in the wirebars of copper, or otherwise.

Jan 1, 1938

By M. G. Corson

Until recently, the characteristics of cast copper have seldom been studied and such study as has been made has been inadequate. The prevailing idea seems to be that since pure copper is infrequently used in the cast stlate, there is no reason for trying to establish precise data regarding the properties of the metal in that condition. On the other hand, wrought copper either in the shape of sheets or wire rarely fails in service, except as a result of the action of reducing gases at the annealing temperatures, so there is little incentive to study the properties of the cast shapes —cakes, bars, ingots and billets—for the sake of tracing the causes of failures of the wrought metal to the cast stock. However, about a decade ago, wirebars of American origin often cracked badly while being hot-rolled in mills in Germany. This Icd to four investigations: by E. Seidl and E. Schieboldll by P. Siebe12 by 0. Bauer and G. Sachs,3 and by G. Welter.4 These authors came to the conclusion that failures in hot-rolling were due essentially to the presence of a wide zone of columnar crystals between t'he thin layer of fine crystal5 near the surfaces of the bars and the large but more nearly equiaxed grains of the central core. This macrostructural defect was explained in turn by the probable upward deviation in the temperature of the metal while it was being poured into the molds of the castling machine. More recently, cast shapes of copper were investigated by X. 1'. Allenh and by C. Blazey. Allen examined vertically cast wirebars and hori-zontally cast wedge cakes of electrolytic tough-pitch copper, but only for the distribution of densities; i.e., porosity. Blazey was interested mainly in the mechanism of the variations in electrical conductivity due to cold-work and anneal, but gave introductively an account of the composi-tion and average densities of the tough-pitch horizontally cast Wirebars used. As far as the present writer can tell, no investigation mas under-taken for the sake of presenting a picture of the distribution of mechanical characteristics in the wirebars of copper, or otherwise.

Jan 1, 1938

By M. G. Corson

UNTIL recently, the characteristics of cast copper have seldom been studied and such study as has been made has been inadequate. The prevailing idea seems to be that since pure copper is infrequently used in the cast state, there is no reason for trying to establish precise data regard-ing the properties of the metal in that condition. On the other hand, wrought copper either in the shape of sheets or wire rarely fails in service, except as a result of the action of reducing gases at the annealing tempera-tures, so there is little incentive to study the properties of the cast shapes -cakes, bars, ingots and billets-for-the sake of tracing the causes of failures of the wrought metal to the cast stock. However, about a decade ago, wirebars of American origin often cracked badly while being hot-rolled in mills in Germany. This led to four investigations: by E. Seidl and E. Schiebold,1 by P. Siebe,2 by O. Bauer and G. Sachs,3 and by G. Welter.4 These authors came to the conclusion that failures in hot-rolling were due essentially to the presence .of a wide zone of columnar crystals between the thin layer of fine crystals near the surfaces of the bars and the large but more nearly equiaxed grains of the central core. This macrostructural defect was explained in turn by the probable upward deviation in the temperature of the metal while it was being poured into the molds of the casting machine. More recently, cast shapes of copper were investigated by N. P. Allen5 and by C. Blazey.6 Allen examined vertically cast wirebars and hori-zontally cast wedge cakes of electrolytic tough-pitch copper, but only for the distribution of densities; i.e., porosity. Blazey was interested mainly in the mechanism of the variations in electrical conductivity clue to cold-work and anneal, but gave introductively an account of the composi-tion and average densities of the tough-pitch horizontally cast wirebars used. As far as the present writer can tell, no investigation was under-taken for the sake of presenting a picture of the distribution of mechanical characteristics in the wirebars of copper, tough-pitch or otherwise.

Jan 1, 1938

By M. G. Corson

UNTIL recently, the characteristics of cast copper have seldom been studied and such study as has been made has been inadequate. The prevailing idea seems to be that since pure copper is infrequently used in the cast state, there is no reason for trying to establish precise data regarding the properties of the metal in that condition. On the other hand, wrought copper either in the shape of sheets or wire rarely fails in service, except as a result of the action of reducing gases at the annealing temperatures, so there is little incentive to study the properties of the cast shapes -cakes, bars, ingots and billets-for the sake of tracing the causes of failures of the wrought metal to the cast stock. However, about a decade ago, wirebars of American origin often cracked badly while being hot-rolled in mills in Germany. This led to four investigations: by E. Seidl and E. Schiebold,1 by P. Siebe,2 by 0. Bauer and G. Sachs,3 and by G. Welter.4 These authors came to the conclusion that failures in hot-rolling were due essentially to the presence of a' wide zone of columnar crystals between the thin layer of fine crystals near the surfaces of the bars and the large but more nearly: equiaxed grains of the central core. This macrostructural defect was explained in turn by the probable upward deviation in the temperature of the metal while it was being poured into the molds of the casting machine. More recently, cast shapes of copper were investigated by N. P. Allen5 and by C. Blazey.6 Allen examined vertically cast wirebars and horizontally cast wedge cakes of electrolytic tough-pitch copper, but only for the distribution of densities; i.e., porosity. Blazey was interested mainly in the mechanism of the variations in electrical conductivity due to cold-work and anneal, but gave introductively an account of the composition and average densities of the tough-pitch horizontally cast wirebars used. As far as the present writer can tell, no investigation was undertaken for the sake of presenting a picture of the distribution of mechanical characteristics in the wirebars of copper, tough-pitch or otherwise.

Jan 1, 1938

COUNCIL OF SECTION DELEGATES A J Duff G H Ruggles E D Gardner E H Torgersen F W Strandberg, Chairman W I Garms H C Weed R D Chapman, Vice-Chairman H M Lavender J A Wilcox F T Moyer. Secretary W C Lawson C F Willis EXECUTIVE COMMITTEE J E Kastrop L Thiessen Past Chairmen R H Smith E H Wisser P D I Honeyman R W Hughes C H Kuzell

Jan 1, 1951

By O. Knacke, H. Barth, W. Gans

The rate of cementation was determined by measuring the time required to consume a thin electrodeposited layer of the cementating metal as indicated by a sudden increase in the electrical potential. The diffusion controlled cathodic current of the more positive metal was measured by conventional electrochemical techniques and compared with the cementation rate under the same experimental conditions. Micrographs revealed different types of crystal growth in different surroundings e.g. dendritic growth in acidic solutions.

Jan 1, 1973

[Alphabetic Section (Page 1): The letter immediately following the member's name indicates grade: M-Member, A-Associate, J-Junior. The numerals following member's grade indicate year of election. The letter following year of election indicates primary Divisional affiliation: A-Mining & Exploration F-Coal B-Minerals Beneficiation G-Petroleum C-Iron and Steel H-Industrial Minerals D-Extractive Metallurgy J-Council o f Education E-Institute o f Metals K-Council o f Economics]

Jan 1, 1961

[Alphabetic Section (Page 689): The letter immediately following the member's name indicates grade: M-Member, A-Associate, J-Junior. The numerals following member's grade indicate year of election. The letter following year of election indicates primary Divisional affiliation: A-Mining & Exploration F-Coal B-Minerals Beneficiation G-Petroleum C-Iron and Steel H-Industrial Minerals D-Extractive Metallurgy J-Council o f Education E-Institute of Metals K-Council o f Economics]

Jan 1, 1961

[Alphabetic Section (Page 729): The letter following the member's name indicates grade: M-Member, A-Associate, J-Junior. The numerals following member's grade indicate year of election. The letter following year of election indicates primary Divisional affiliation: A-Mining & Exploration F-Coal B-Minerals Beneficiation G-Petroleum C-Iron and Steel H-Industrial Minerals D-Extractive Metallurgy J-Council o f Education E-Institute o f Metals K-Council o f Economics]

Jan 1, 1961

By C. M. Haight

The mine blacksmith and drill-steel sharpening shop at the Franklin mine of the New Jersey Zinc Co. is on the surface, adjoining the main shaft. It is a brick building, 51 by 30 ft. inside dimensions, with a corrugated iron roof and concrete floor. .About two-thirds of the steels used are brought up through the main shaft; the remainder through two auxiliary shafts and are carried to the shop by team or truck. At each shaft sufficiently large stocks of sharp drills of various typcs are kept to replace all the dull steels that may be sent up; while at the shop enough sharp drills are kept to replace the dull steels in the stocks kept at the auxiliary shafts. Though this entails keeping a larger number of drill steels in service than might be required by other methods, there is less hurry in the sharpening shop and the steels have a longer period of rest. If a rest from use enables steel to recover from fatigue strains, this method secures that rest. The forms shown in Fig. 1 are supplied to each shift boss in books of 100. These are used to requisition sharp drills from the shaft stocks and cnable the men at the tops of the shafts to sort out the required sizes and to hare them ready to be sent to the various shaft stations. At one of the auxiliary shafts, the dull drills are placed on a platform from which they are dumped into the body of the wagon that takes them to the shop.

Jan 1, 1927

By John T. Eash, Clair Upthegrove

During recent years nickel has had an increasingly important role as an alloying element in the copper-tin bronzes. Nickel additions not only produce better casting alloys but also make alloys whose properties can be varied by precipitation hardening; thus leading to increased commercial application of copper-nickel-tin alloys. Recent investigations have indicated a decrease in the solubility of tin in the alpha phase as the annealing temperature is lowered and as the nickel content is increased within certain limits. A further change caused by the nickel additions is produced in the excess phase of the copper-tin bronzes. The alpha plus delta eutectoid is replaced by a clear precipitated constituent in the alloys containing up to 15 per cent tin and not less than 1 per cent nickel. This paper has a dual purpose. The first is to present a new determination of the alpha-phase boundary in alloys containing from 0 to 20 per cent nickel, together with the liquidus and solidus temperatures above that field. The second purpose is to give the equilibrium conditions existing in alloys exceeding the alpha phase containing up to 31 per cent tin and 5 per cent nickel, so that the disappearance of the alpha plus delta eutectoid constituent may be explained. After considering the earlier investigations of the related alloy systems and the experimental procedure used in this investigation, the alloys will be discussed in groups as separate quasibinary systems containing constant amounts of nickel. The systems considered contain 0, 1, 2, 3, 5, 10 and 20 per cent nickel. The straight copper-tin system was reinvesti-gated in order to establish a foundation on which to build the remaining material. The 1 per cent nickel alloys studied give the relations existing in the region of the eutectoid transformation between the copper-tin system and the 2 per cent nickel copper-tin system which has been investigated in detail. The thorough examination of the latter system was made since 2 per cent of nickel is representative of the commercial additions to the cast bronzes and also because it is sufficient to produce

Jan 1, 1933