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By E. W. Davis

IF the tonnage of merchantable iron ore remaining in the Lake Superior district is divided by the average of the annual shipments for the past 20 years, it will be found that this ore supply will be exhausted in approximately 35 years. This computed exhaustion period would be an indication of the future activities of the iron-mining industry if it were not for the fact that merchantable ore is being manufactured from low-grade ore, of which there is an almost inexhaustible supply in the Lake Superior district. It is true that at present only the simplest of these low-grade ores are being concentrated to any considerable extent, but progress is being made with the treatment of the more complex ores, and now, in addition to 20 washing plants on the Mesabi Range, three plants are equipped with jigs for the treatment of ore that cannot be concentrated simply by washing. The latest addition to the ore-treating plants of the Mesabi Range is a magnetic roasting and concentration plant at Cooley, Minn., in which ore that cannot be concentrated either by washing or by jigging is roasted to the magnetic state and concentrated on magnetic separators. This plant is beginning its third season of operation, and while it is too soon to make definite predictions, there are strong indica-tions that this new process may make commercially possible the manu-facture of high-grade, merchantable iron ore from large quantities of low-grade ore now considered worthless. After the iron oxide contained in an ore has been converted to mag-netite, almost any desired grade of concentrate can be produced, using magnetic-concentration equipment of the types now in general use for the concentration of the natural magnetites of New York, New Jersey and Pennsylvania. The conversion of hematite (Fe203) to magnetite (Fe304) is easily accomplished by heating the ore to a dull red tempera-ture in a reducing atmosphere. The reaction is slightly endothermic, and while it requires 200 B.t.u. to heat to 900° F. one pound of hematite ore containing 45 per cent Fe, it requires only 100 B.t.u. to convert the oxide into magnetite. In the laboratory, using small quantities of ore, this conversion is very simple, but large furnaces suitable for commercial

Jan 1, 1936

CONTENTS PAGE. WHITE, DAVID.-Environmental Conditions of Deposition of Coal. Discussed by E. C. Jeffrey, George H. Ashley, Reinhardt Thiessen, S. W. Parr, David B. Reger, Wilbur A. Nelson, James F. Kemp, E. S. Moore, Homer G. Turner, David White, A. C. Noé, W. A. I. M. van Waterschoot van der Gracht 2 THIESSEN, REINHARDT.-The Constitution of Coal. Discussed by Edward C. Jeffrey, Reinhardt Thiessen, Ralph H. Sweetser, David White 12 TURNER, HOMER G.-Microscopical Structure of Anthracite. Discussed by E. S. Moore, Edward C. Jeffrey, Reinhardt Thiessen, H. J. Rose, James F. Kemp, David White, Clarence A. Seyler, A. C. Noé 14 JEFFREY, EDWARD C.-Coal in Relation to Coke. Discussed by H. J. Rose, David White, E. S. Sinkinson, S. W. Parr, James F. Kemp, Edward C. Jeffrey, Reinhardt Thiessen, Chas. R. Fettke 17 FRANCIS, W., and WHEELER, R. V.-The Resolution of Coal by Oxidation. Discussed by Edward C. Jeffrey, S. W. Parr, E. S. Sinkinson, Reinhardt Thiessen, David White 23 TIDESWELL, F. V., and WHEELER, R. V.-The Constitution of Coal. Discussed by David White, A. C. Fieldner 24 JOLLY, J., and WHEELER, R. V.-Organic Sulfur Compounds in Coal. Discussed by S. W. Parr 25 SINNATT, F. S.-Selective Combustion in Coal. Discussed by J. D. Davis, A. C. Fieldner, Geo. S. Rice, W. M. Grant, H. J. Rose, S. W. Parr, David White 25 COBB, JOHN W.-Nitrogenous Constituents of Coal. Discussed by S. W. Parr, H. J. Rose, Reinhardt Thiessen 28 PARR, S. W., and HOBART, F. B.-Coal and Oxygen. Discussed by J. D. Davis, W. T. Thorm, Jr., S. W. Parr, H. J. Rose, A. C. Fieldner, F. F. Jorgensen, David White, W. M. Grant 30 FIELDNER, A. C., and DAVIS, J. D.-Modern Views of Chemistry of Coals of Different Ranks as Conglomerates. Discussed by S. W. Parr, David White, Reinhardt Thiessen, A. C. Fieldner, Clarence A. Seyler 32 EBY, J. BRIAN.-Contact Metamorphism of Some Colorado Coals. Discussed by Geo. C. McFarlane, W. T. Thom, Jr 35 WHITE, DAVID.-Progressive Regional Carbonization of Coals. Discussed by A. C. Fieldner, Homer G. Turner, W. A. J. M. van Waterschoot van der Gracht, A. C. Noé 37 THOM, W. T., JR.-Moisture as a Component of the Volatile Matter of Coal. Discussed by A. C. Fieldner, S. W. Parr, Clarence A. Seyler, W. T. Thom, Jr., R. D. Hall 39

Jan 7, 1925

By Charles H. Jacoby, Stanley J. LeFond

Salt, or halite, has had a long and most varied history. While we know the Chinese were producing salt as early as 3000 B.C., the first written reference to salt appears in the book of Job recorded about 2250 B.C., which reads: "Can nothing which is unsavory be eaten without salt?" We do not know when man first used or realized that he needed salt. Perhaps one of our early Eolithic ancestors noted a piece of salt shining along the shore of a salt lake or a bay. He may have been attracted by its shining luster and tasted it. He found that it had a tart, zesty, distinctive flavor and perhaps chewing a large piece, became ill. However, by experimentation he soon learned that taken in the proper proportions salt was a very pleasant additive to his food. He may have noticed, too, that it increased his feeling of well-being. Thus, when the curtain of recorded history rises, we find man using salt for his health's sake, seasoning his food with it, feeding it to his animals, and using it in many superstitious and religious ceremonies. These uses, however, are a far cry from the uses for salt today. The first attempts of white man to make salt in continental United States were reported in the year 1614, while the first commercial production was in 1790. Practically all of this salt was for human consumption, preserving food, and curing hides. Prior to the coming of the "white man" Indians are known to have made salt from such salt springs as those that existed at Avery Island, La., Charleston, W.Va., Saltville, Va., and Onondaga, N.Y. In 1862 the first rock salt was mined in the U.S. from the Avery Island salt dome. Almost immediately thereafter, rock salt was mined at Saltville, Va., and then at Retsof, N.Y., in 1885. Of the more than 40 million tons produced annually in the United States, about 68% or 27 million tons are consumed by the chemical industry in the production of chlorine, caustic soda, hydrochloric acid, sodium metal, and some 30 other basic chemicals. These basic chemicals, in turn, are used in the preparation of approximately 14,000 chemicals which range from soap and detergents, to such chlorinated hydrocarbons as DDT, BHC, carbon tetrachloride, etc.

Jan 1, 1975

By N. A. Gjostein

The self-diffusion coefficient D, for a surface near the (100) plane in copper was determined by means of the Mullins theory of thermal grooving, and was found to obey the Arrhenius relationship, and Do = 6.5 x 10' sq cm per sec. Suppression of surface diffusion by chemisorbed impurities encounters difliculties as a satisfactory explanation for the large Q, and Do. Instead, a model is presented which indicates that Q,, as determined by a mass-transport technique, may involve both the energy needed to form an adsorbed atom from a ledge in the surface as well as that for the movement of the adsorbed atom.; LITERATURE reviews1-3 indicate that the mechanism of self-diffusion on metal surfaces is not clearly understood. The lack of experimental data on the temperature variation of the surface self-diffusion coefficient DJ has contributed greatly to this situation. Radioactive tracer techniques4-rn have been used to measure Ds, but for many years only Nicker-son and Parker8 had determined (for polycrystalline silver) an activation energy B, and a frequency factor Do for the surface self-diffusion process. Even in this case, a mechanism could not be clearly inferred because it was suspeted7 that a contribution from volume diffusion was not taken into account by the investigators. Some later work by Li and parkere on polycrystalline gold, in which they obtained essentially the same results as for silver and in which volume diffusion could be accounted for, seems to invalidate this criticism. In 1957, Mullins10'11 developed the theory for the thermal grooving process. This advance has opened a new and promising technique for measuring the surface self-diffusion coefficient Ds. Recognizing that a thermal groove may form by several different mass transport processes, Mullins first consideredlo the cases where a) the groove forms by evaporation and condensation or b) by diffusion along the groove surface, in either case, in a system where a metal surface is in contact with only its dilute vapor phase. In a later paper," he extended the treatment to cases where the groove forms by volume diffusion into c) the solid phase or d) by mass transport through a passive gaseous phase at 1 atm pressure. The time dependence of the groove dimensions and the shape of the groove profiles predicted by Mullins' treat-

Jan 1, 1962

By E. W. Davis

If the tonnage of merchantable iron ore remaining in the Lake Superior district is divided by the average of the annual shipments for the past 20 years, it will be found that this ore supply will be exhausted in approximately 35 years. This computed exhaustion period would be an indication of the future activities of the iron-mining industry if it were not for the fact that merchantable ore is being manufactured from low-grade ore, of which there is an almost inexhaustible supply in the Lake Superior district. It is true that at present only the simplest of these low-grade ores are being concentrated to any considerable extent, but progress is being made with the treatment of the more complex ores, and now, in addition to 20 washing plants on the Mesabi Range, three plants are equipped with jigs for the treatment of ore that cannot be concentrated simply by washing. The latest addition to the ore-treating plants of the Mesabi Range is a magnetic roasting and concentration plant at Cooley, Minn., in which ore that cannot be concentrated either by washing or by jigging is roasted to the magnetic state and concentrated on magnetic separators. This plant is beginning its third season of operation, and while it is too soon to make definite predictions, there are strong indications that this new process may make commercially possible the manufacture of high-grade, merchantable iron ore from large quantities of low-grade ore now considered worthless. After the iron oxide contained in an ore has been converted to magnetite, almost any desired grade of concentrate can be produced, using magnetic-concentration equipment of the types now in general use for the concentration of the natural magnetites of New York, New Jersey and Pennsylvania. The conversion of hematite (Fe203) to magnetite (Fe3O4) is easily accomplished by heating the ore to a dull red temperature in a reducing atmosphere. The reaction is slightly endothermic, and while it requires 200 B.t.u. to heat to 900' F. one pound of hematite ore containing 45 per cent Fe, it requires only 100 B.t.u. to convert the oxide into magnetite. In the laboratory, using small quantities of ore, this conversion is very simple, but large furnaces suitable for commercial

Jan 1, 1939

By E. W. Davis

If the tonnage of merchantable iron ore remaining in the Lake Superior district is divided by the average of the annual shipments for the past 20 years, it will be found that this ore supply will be exhausted in approximately 35 years. This computed exhaustion period would be an indication of the future activities of the iron-mining industry if it were not for the fact that merchantable ore is being manufactured from low-grade ore, of which there is an almost inexhaustible supply in the Lake Superior district. It is true that at present only the simplest of these low-grade ores are being concentrated to any considerable extent, but progress is being made with the treatment of the more complex ores, and now, in addition to 20 washing plants on the Mesabi Range, three plants are equipped with jigs for the treatment of ore that cannot be concentrated simply by washing. The latest addition to the ore-treating plants of the Mesabi Range is a magnetic roasting and concentration plant at Cooley, Minn., in which ore that cannot be concentrated either by washing or by jigging is roasted to the magnetic state and concentrated on magnetic separators. This plant is beginning its third season of operation, and while it is too soon to make definite predictions, there are strong indications that this new process may make commercially possible the manufacture of high-grade, merchantable iron ore from large quantities of low-grade ore now considered worthless. After the iron oxide contained in an ore has been converted to magnetite, almost any desired grade of concentrate can be produced, using magnetic-concentration equipment of the types now in general use for the concentration of the natural magnetites of New York, New Jersey and Pennsylvania. The conversion of hematite (Fe203) to magnetite (Fe3O4) is easily accomplished by heating the ore to a dull red temperature in a reducing atmosphere. The reaction is slightly endothermic, and while it requires 200 B.t.u. to heat to 900' F. one pound of hematite ore containing 45 per cent Fe, it requires only 100 B.t.u. to convert the oxide into magnetite. In the laboratory, using small quantities of ore, this conversion is very simple, but large furnaces suitable for commercial

Jan 1, 1939

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

By V. Patarini, D. Kuehl, F. Galasso, M. Salkind

In recent years, a great deal of research has been directed toward the production of continuous low-density, high-strength, high-modulus boron fibers for aerospace applications. A technique which has proven to be quite successful for forming these fibers involves the reaction of boron trichloride and hydrogen on a hot tungsten wire. In this process, a boron fiber is produced which consists of a tungsten boride core covered with amorphous or crystalline boron depending on the temperature of the preparation.2,3 The purpose of this paper is to present the properties which have been obtained to date from measurements and observations on these fibers. Selected samples of boron filament produced by reacting boron trichloride and hydrogen on a 0.5 by 10-3 in. diam tungsten wire substrate using different reacting temperatures were cross-sectioned, polished, and photomicrographed with cross-polarized light. The temperature of the wire was measured using a two-color optical pyrometer. Photomicrographs of these samples are shown in Fig. 1. Three general types of boron, in addition to the tungsten borides, have been identified by means of X-ray powder diffraction techniques: a) at low temperatures (below 1400°C) the boron is deposited in the amorphous form; b) at temperatures between 1400° and 1500°C the boron is deposited in the ß tetragonal form; and, c) above 1500°C the boron is deposited in the B rhom-bohedral form. In the depositing range of 1400" to 1500°C the boron initially deposits as amorphous and becomes crystalline as evidenced by the large equi-axed grains which then merge into columnar grains in later stages of boron deposition. This can be seen in Fig. 1 and has been observed in the X-ray patterns of these fibers, which contain both halos from the amorphous boron and lines from the ß tetragonal form. Above 1500°C the only boron reflections observed in the X-ray patterns were those of the ß rhombohedral form and only columnar grains are seen in the photomicrographs. Photomicrographs of the surface in Fig. 2 show the smooth-surface kernal-type deposition which corresponds to the amorphous form and the rougher surfaces which correspond to the crystalline form. Mechanical measurements were made on amorphous boron produced at 1300°C rather than the crystalline boron because the strengths of these filaments were greater and were more consistent. A tensile tester consisting of a fixed crosshead containing a double

Jan 1, 1967

By Morris Cohen

STAFF: Editor, Gerhard Derge Acting Editor, Paul G. Shewmon Carnegie Institute of Technology Schenley Park Pittsburgh 13, Pa. Editorial Assistant, M. A. Redmerski Production Editor, Otto T. Johnson THE METALLURGICAL SOCIETY: Karl L. Fetters, President; J.S. Smart, Jr., Past-President; R. C. Cole, Vice President; R. L. Hennebach, Treasurer; R. W. Shearman, Secretary. PUBLICATIONS COMMITTEE OF THE METALLURGICAL SOCIETY: W. O. Phil-brook, Chairman; H. L. Bishop, R. C. Cole, J. N. Hobstetter, W. A. Krivsky, E. R. Morgan, F. C. Langenberg, R. E. Lund, Paul Queneau, L. L. Seigle, R. L. Smith, and T. V. Wainwright. Review and selection of manuscripts is under the supervision of the following Publicotions Committes: Extractive Metallurgy Division: R. E. Lund, Chairman; M. E. Wadsworth, Vice Chairman; D. H. Baker, Jr., G. M. Bell, R. E. Grace, W. A. Krivsky, R. A. Lewis, Charles O'Neill, A. W. Schlechten, R. E. Shinkoskey, and W. W. Stephens. Iran and Steel Division: T. V. Wainright, Choirman; H. L. Bishop, R. E. Boni, T. E. Dancy, D. W. Murphy, Johannes M. Uys, J. B. Wogstoff, and R. G. Ward. Institute of Metals Division: J. N. Hobstetter, Chairman; P. A. Beck, J. J. Becker, G. F. Bolling, J. 0. Brittain, J. B. Clark, R. S. Davis, A. E. Dwight, R. W. Fountain, L. R. Girifolco, J. C. Gurland, H. S. Kalish, E. L. Harmon, J. J. Heger, A. A. Hendrickson, L. Himmel, J. P. Hirth, H. H. Johnson, Jr., R. R. Nosh, T. N. Rhodin, R. H. Richman, H. C. Rogers, W. Rostoker, C. Sherby, C. W. Spencer, L. Slifkin, J. K. Stanley, R. Steinitz, H. C. Stumpf, and R. Swalin. Published bimonthly by the Americon Institute of Mining, Metallurgicol, and Petroleum Engineers, Inc., 345 East 47th Street, New York 17, N. Y. Telephone PLaza 2-6800. Subscription $30 peryear for non-AIME members in United States and North, South, and Centrol America; $32, foreign; $30per$7.50 for AlME members. Single copies, $6.00, single copies foreign, $6.50. The AlME is not responsible for any stotement made or opinion expressed in its publications ... Copyright 1962 by the American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc. . . . Registered cable address, AlME New York . . . Indexed in Engineering Index, Industrial Arts Index, and Chemical Abstracts . . . Second class postage paid at New York, N. Y., and Ann Arbor, Mich. Volume 224, Number 4.

Jan 1, 1962

By S. Stutz

Three years ago, at the Philadelphia meeting, in February, 1881, the author had the pleasure of presenting to the Institute a paper on coal-washing machinery.* Since that time many new machines, with important improvements and labor-saving apparatus, have been introduced, the construction and description of which may be of interest to some of the members of the Institute. By referring to the above-mentioned paper, and more especially to Plate IV., representing a vertical section of a coal-washer, it will be noticed that the bottom of the plunger-box B is made level or horizontal, and supports a spring-buffer F for the purpose of limiting the down-stroke of the plunger P and receiving the impacts of the latter. Althongh the construction of the box, in view of these impacts, received from the start the proper attention (the bottom of the chamber 3 being made of three thicknesses of 3-inch planks, resting on 6-inch sqnare columns), yet, through careless working of the machinery, without the necessary water in the box, it proved in several instances not strong enough, and had to be changed. To prevent such interruptions in future, it became necessary to devise some means for relieving the machine from the impacts of the plunger altogether. This has been accomplished by the arrangement shown upon Plate I. of this paper, representing a new waesher; and not only has the difficulty been overcome, but also sorne other advantages have been obtained, as will be seen further on. The compartments +, A' of the separator-box have been set upon heavy cast-iron brackets B, leaving sufficient space below the bottom for the buffer F and the sediment-valve K. By means of the plunger-rod 6 passing through the stuffing-box s to the outside, and provided at its lower end with a shoe a, the impacts of the plunger are now transmitted from the buffer F directly to the foundation. At the same time a better guide for the plunger P in its up and down movement has been obtained. The plunger of the former machine had only the guide I and the yoke Y, whereas the new machine has an additional guide in the stuffing-box s, thus preventing wear and friction of the plunger against the lining of the box. Further-

Jan 1, 1884

By David J. Mack

A survey and critical appraisal of published information about Young's modulus was originally made by the writer because of a complete lack of information about this very important quantity in works on. mechanics, physical metallurgy, physics, and other sciences. It was felt that a comprehensive summary of such information about Young's modulus might be of general interest and may suggest new problems or lines of attack on other problems that involve E. Hence this paper has been prepared even though it is only a review, with no new ideas or experimental data. The references are only those used in assembling the paper. No attempt was made to compile a complete bibliography on the subject of Young's modulus. CalculatioX oP YouNg's Modulus from Theoretical or Empirical CoNsidera-tions Many attempts have been made to compute E from theoretical considerations. The earliest calculations were probably those of Tomlenson (1883) and Souther-land (1891), but Fess'enden4',~ made extensive calculations a few years later and arrived at the relationship: £ = 78.TOw(i)* where V is the atomic volume. In 1923, Peczalski, working from the same standpoint but with more information available on atomic structure, arrived at an identical relationship, which he expressed as: where B is a constant of value about 8 . 107, p is density and mis atomic weight; the atomic volume, of course, being ml p. Portevind4 immediately pointcd out that while the equations of Fessenden and Peczalski were true of the common metals, they gave low values for the refractory metals with high moduli (Fig. I). He showed (Fig. 2) that much better concordance was obtained by means of an empirical equation of the form: F- KT" where K is a constant; T the absolute melting point; V, atomic volume, and a and b constants of value approximately I and 2 respectively. This constant K in the Portevin equation is not necessarily the same for all elements, as shown by Thompson. Other equations for E based upon theoretical considerations have been derived by Honda and Yamada49 and Lasareff.50 The most recent calculations of elastic moduli based upon quantum mechanics are probably those of Fuchs He extended the method of Wigner and Seitz for calculating the lattice energy and compressibility of monovalent metals and computed the elastic constants of lithium, 18

Jan 1, 1946

By William Kent

ABOUT a year ago, the writer had occasion to assist Mr. John L. Gill, Jr., of the Pittsburgh. Car-wheel Works, in making a trial of his new testing machine. A piece of Bessemer steel, of about .34 carbon, was used as a test-piece, turned to a sectional area of one square inch for a length of five inches between shoulders, and pro¬vided with large round heads, which were fitted to what is called the " Wade grip." Measurements of elongation, accurate to , 1/10000 of an inch, were made by a special apparatus containing two micrometer screws, with electric contact attachment. The machine was operated by hand-power. Readings of elongation were taken at each increment of 2000 pounds stress per square inch, up to 44,000 pounds, the elongation corresponding to the latter figure being .0088 inch. The elongations up to this point remained almost exactly proportional to the stresses, the strain diagram, as shown on the Plate, from the origin to the point A, being a straight line (the deviation of no observation from the straight line being greater than .0002 inch). There being no indication of an approach to the elastic limit, the attendant at the hand-wheel and scale-beam was told to proceed as usual and move the poise forward 2000 pounds, or to 46,000, and turn the wheel until the beam was balanced. Noticing that the beam did not rise in the usual time, and that the elongation was increasing rapidly, the writer called to the attendant to stop turning the hand-wheel and to push the poise backwards until the scale-beam balanced. Instead of balancing at between 44,000 and 46,000 pounds, as was expected, it balanced at 40,000 pounds, and the elongation had increased to .0343 inch (or more than four times that recorded at 44,000 pounds), as plotted at the point B, the dotted line between A and B showing the supposed course of the strain diagram between these two points. Immediately upon recording the elongation the writer said to Mr. Gill, who was standing alongside: "This phenomena is without a parallel in my experience, and I know of but one way to account for it. The piece must actually be broken in its interior, through a flaw or weak portion of the metal. The test-piece is now equivalent to a tube, with

Jan 1, 1880

By William Kent

About a year ago, the writer had occasion to assist Mr. John L. Gill, Jr., of the Pittsburgh Car-wheel Works, in malting a trial of his new testing machine. A piece of Bessemer steel, of about .34 carbon, was used as a test-piece, turned to a sectional area of one square inch for a length of five inches between shoulders, and provided with large round heads, which were fitted to what is called the " Wade grip." Measurements of elongation, accurate to 1/10000 of an inch, were made by a special apparatus containing two micrometer screws, with electric contact attachment. The machine was operated by hand-power. Readings of elongation were taken at each increment of 2000 pounds stress per square inch, up to 44,000 pounds, the elongation corresponding to the latter figure being .0085 inch. The elongations up to this point remained almost exactly proportional to the stresses, the strain diagram, as shown on the Plate, from the origin to the point A, being a straight line (the deviation of no observation from the straight line being greater than .0002 inch). There being no indication of an approach to the elastic limit, the attendant at the hand-wheel and scale-beam wits told to proceed as usual and move the poise forward 2000 pounds, or to 46,000, and turn the wheel until the beam was balanced. Noticing that the beam did not rise in the usual time, and that the elongation was increasing rapidly, the writer called to the attendant to stop turning the hantl-wheel and to push the poise backwards until the scale-beam balanced. Instead of balancing at between 44,000 and 46,000 pounds, as was expected, it balanced at 40,000 pounds, and the elongation had increased to .0343 inch (or more than four times that recorded at 34,000 pounds), as plotted at the point B, the dotted line between A and B showing the supposed course of' the strain diagram between these two points. Immediately upon recording the elongation the writer said to Mr. Gill, who was standing alongside: "This phenomena is without a parallel in my experience, and I know of but one way to account for it. The piece. must actually be broken in its interior, through a flaw or weak portion of the metal. The test-piece is now equivalent to a tube, with

Jan 1, 1880

By John Campbell

An approximate theoretical model is proposed to quantitatively predict freezing ranges Tf and hydrostatic tensions P developed within solidifying binary alloys, allowing for a certain amount of diffusion of solute in the solid during solidification. The maxima in ATf and AP as functions of composition are shorn to occur at smaller solute concentrations than would be expected from the equilibrium diagram, and are found to correspond closely to experimentally observed maxima in microporosity. THE freezing range of simple binary alloys appears to have been little studied, except for certain indirect observations on the defects, particularly microporosity and hot tearing, arising in long freezing range materials. Two theories relating to the freezing range of alloys and its effect upon porosity are reasonably well established, and appear to have been held in isolation from each other: a) From purely equilibrium considerations early researchers expected that an increase in solute content of an alloy should increase the freezing range (defined here as the equilibrium freezing range ?Tf = Tl-Ts where TL and Ts are the liquidus and solidus temperatures, respectively) and thereby increase the width of the pasty zone for a given set of conditions. This in turn should increase the difficulty of feeding the residual liquid through the dendrite mesh to compensate for the contraction on solidification, and consequently tend to increase the observed amount of porosity. From qualitative observations on steels Czikel1 reports an increase in porosity with increasing carbon content up to 0.46 pct C. More careful measurements by Whittenberger and Rhines2 on fourteen different alloy systems showed an approximately linear relation between ?Tf and pct porosity (although unfortunately the precise experimental data is not given). b) Conversely however, other authors3"5 propose that porosity is reduced by the presence of increased amounts of eutectic present at the final solidification temperature. Lees7 and Bochvar6 claim that the hot tearing of alloys is similarly reduced. Scheuer8 has put forward a theory to explain this effect, Fig. 1. The argument is basically that solidification progresses on a plane front through a relatively open dendrite network and is thus (the argument is not developed more explicitly) easier to feed. One would expect effect a) to operate at low solute contents, and b) to be important at higher solute contents, so that at some critical composition a max-

Jan 1, 1970

By Lester Guttman

THE connection between short-range order and thermodynamic activities in binary solid solutions has been pointed out by Birchenall1 who calculated approximate values of the energy of interaction of Zn and Cu and of the degree of short-range order in alpha-brass at one composition and two temperatures. The purpose of this note is to call attention to a somewhat more accurate theory than that used by Birchenall and to extend the calculations to a wider range of temperatures and compositions as a means of testing its applicability. This is an example of the well-known general method of comparing measured thermo-dynamic functions of a system with those calculated from a microscopic model by means of statistical mechanics. In this case, mathematical approximations must be used which make difficult any decision about the validity of the model. Birchenall's statistical method resembles closely that called by Fowler and Guggenheim2 the "quasi-chemical" method which has been shown to lead in certain cases to results identical with those obtained by the method of Bethe.3 The quasi-chemical method has been extended by Takagi4 to give general formulae for the free energy of binary solid solutions based on several lattices at all compositions and temperatures. Specifically, he treats the four systems typified by: I. ß-brass; 2. a- brass; 3. AuCu3; 4. AuCu. When the temperature is so high that no long-range order exists, these formulae reduce to the same form for all lattice types, namely: [ ] Here the symbols have the following meanings: [F-Helmholtz free energy E-energy S-entropy k-the gas constant per molecule z-coordination number, (e.g. 12 in. a-brass). N-total number of atoms c-atomic fraction of A] VAA, VBB, VAB-energy per bond of the corresponding bonds log means log, throughout The superscript 0 denotes the thermo- dynamic function in the standard state, which has been chosen to be pure A or B with the same crystal structure as the solid solution. The quantity x is the ratio of the number of A-A bonds to the total number and for minimum F satisfies the equilibrium condition [ ] The free energy may also be written in terms of µA and µB, the chemical potentials or partial free energies per atom:

Jan 1, 1948

By E. A. Calnan, B. E. Williams

IN the development of a new treatment for the prediction of deformation textures,'-' it was noted that for no metals are there experimentally determined tension textures with which the predictions may be compared. There is a considerable knowledge of drawing textures and previous workers have been content to consider these as equivalent to tension textures for the purposes of comparison. It is shown, however, in the new treatment that the tension and drawing textures are not necessarily identical, the radial compression exerted by the dies in the drawing operation producing some modification of the tension texture. In particular for the face-centered cubic metals it is predicted that for drawing the final texture should be [1ll] with a spread towards [211] (a more detailed derivation of this texture has been made by Calnan3). This has been amply confirmed by experiment, see Hibbard.6 For the pure tension case, however, the treatment predicts intermediate [1ll] and [loo] textures leading to a [211] end-point, while all previous treatments have predicted the final texture as [1ll] with in some cases an additional [loo] component. Thus evidence that the pure tension end-point is the [211], or at least that [1ll] and [l00] are not the final textures, should provide a valuable test of the new treatment. Accordingly some experiments were made on aluminum. Three aluminum specimens were examined in detail, one of cold-rolled high purity rod (99.99 pct), specimen A, and two of commercial extruded rod of purity 99.4 pct, specimens B and C. The initial annealing treatments were: A, 1½ hr at 400°C; B, 2 hr at 400°C; C, 1½ hr at 650°C. The principal difficulty is that of obtaining sufficient elongation before fracture occurs. This was overcome to some extent by giving a softening heat treatment, 1 hr at 300°C, after each 15 pct of extension. Vickers hardness measurements gave values before and after the softening treatment of about 30 and 28, respectively, in comparison with the initial value of about 19 corresponding to fully annealed material. From recent observations in this laboratory it is concluded that this small recovery corresponds to a polygonization process rather than recrystallization proper and consequently the preferred orientation is unaffected. At the higher extensions, however, some slight necking of the specimens took place and it was necessary to turn them down to a uniform cross-section before

Jan 1, 1953

By F. L. Bosqui

Discussion of the paper of F. L. Bosqui, presented at the San Francisco meeting, September, 1915, and printed in Bulletin No. 101, May, 1915, pp. 997 to 1033. H. A. WHITE, Springs, Transvaal (communication to the Secretary*). -It is, as the author points out in his valuable paper, a, fact, that in many plants the "trommel washings" are allowed to become eyesores, but the simpler system of pumping the entire product direct to the tube-mill circuit will avoid the extra expense of separation and small-scale treatment when one considers the relative distance of the points and the proportionately small amount of water. It is a matter of record that in stamp batteries the increase of weight has been developed concurrently with the increased use of tube mills, but independently and on its own merits. The satisfactory duty, excellent running time, and freedom from breakages in the newer mills, such as the Modder Deep, with 2,000-1b. stamps, will probably go far in removing some of the conservative prejudices mentioned by Mr. Bosqui. The success of the City Deep trial of the Nissen stamp cannot be entirely attributed to better feed distribution and discharge effects (published experiments on two-face discharge mortar boxes showed no advantages). Attention is directed to the treatment costs given by the author both before and after the increased capacity resulting from the addition of 16 Nissen stamps at Modder B. It will be observed that the only item of cost resisting the tendency to reduction caused by increased tonnage is that of milling, which has risen 1.3c. With reference to the provision for amalgamation in the new plans, it seems obvious that a great loss of head would be eliminated by passing the tube cone overflow over a separate top series of plates; three at the top and three at the bottom will effect the maximum amalgamation. This plan is followed at the Princess Estate and Gold Mining Co., Ltd., Modderfontein Deep Levels, Ltd., and Geduld Proprietary. Mines, Ltd., but elsewhere reliance is placed upon ample cone capacity and the underflow only is passed over three plates after going through the tube mill, while the overflow is passed direct to the cyanide works; both methods avoid the largely unnecessary elevation of considerable quantities of water, fine sand and slime involved in Mr. Bosqui's scheme.

Jan 1, 1916

HARRY B. BARREN Harry B. Barren, born in Cleveland, Ohio, May 31, 1888, died in Indiana Harbor, Ind., on Mar. 18, 1918. After graduating from the Case School of. Applied Science of Cleveland, class of 1910, he spent a year at the Youngstown, Ohio, plant of the Carnegie Steel Co. and the following two years with the National Tube Co. in Lorraine, Ohio. In 1913, he went to Indiana Harbor as assistant superintendent of the blast furnaces of the Inland Steel Co. Four months later, he was made superintendent. On Feb. 11, 1914, he was married to Miss Anna E. Jones in Cleveland and is survived by his widow and two sons, and by his parents Mr. and Mrs. H. A. Barren, of Cleveland, and a brother Kenneth, a lieutenant in the 309th Engineers, stationed at Camp Taylor, Louisville, Ky. CHAS. H. JOHNSON Charles Harmany Johnson died Dec. 10, 1918, at his home in New Castle, Pa., after an illness of more than four weeks brought about by a complete nervous collapse. He was born near Clinton, Lawrence Co. Pa., July 9, 1870, a son of George W. and Elizabeth A. Johnson. His parents moved to New Castle when he was two years old, where he attended the public schools of New Castle. He then attended Allegheny College, and later Massachusetts Institute of Technology where he graduated as a mining engineer. For a year and a half after completing his work at Boston he was connected with the Mesaba Ore Range in Minnesota, and then returned to New Castle and became associated with his father in the operation of the old sheet mill, which was converted into a tin mill and later sold to the American Sheet and Tin Plate Co. Since that time he has been actively engaged with his father in the limestone business and other industries. At the time of his death Mr. Johnson was general manager of the Pittsburg Limestone Co., the G. W. Johnson Limestone Co., the Lawrence Limestone Co., the Keystone Limestone Co., and the Mahoning Limestone Co., all of which have quarries in Lawrence, Butler, Blair and Armstrong counties and also in Maryland and West Virginia. He was president of the Johnson Bronze Co., the National Stone Co., and the

Jan 3, 1919

By Frederick Vickery

THE discovery of oil on the Goleta anticline has extended the petroliferous areas of California 18 miles west of the previous limit at Summerland and 35 miles south of the fields at Santa Maria. In each of these localities the oil is found in the Miocene-Pliocene strata, but as the oil at Goleta is found in the Sespe formation, which is generally considered as Oligocene or lowermost Miocene, the Goleta field extends the production of that horizon 52 miles west of South Mountain, the previous western outpost. Two horizons of high-gravity, paraffin-base oil have been found at shallow depths, and the exploratory well, Goleta No. 1, is now being drilled to test the productivity of an expected horizon in the Meganos formation. The Goleta structure is 12 miles west of the city of Santa Barbara and 2 miles north of the coast. Although it is within part of the old Spanish Rancho, Los Pueblos, it corresponds to T. 4 N., R. 29 W., S. B. B. and M., Santa Barbara county, California. The discovery well, Goleta No. 1 was drilled by the Miley Petroleum Ex-ploration Co. on the Tecolote ranch in the part of the Spanish grant corresponding to the sw. 1/4 of the nw. 1/4 of Section 3. Despite the apparent isolated position of the Goleta field, it is within the Ventura basin. The idea that the Ventura basin terminates at the ocean beach near the city of Ventura is neither sup-ported by the geologic structures nor the sequence of strata west of that city. This basin at the present time is known on the land as the Santa Clara valley and beneath the sea as the Santa Barbara channel. It extends westward to Point Concepcion. The Ventura basin, before the Miocene and Pliocene epochs of deformation, was much broader than at the present time. It is bounded by two lines of uplift, the Santa Ynez range on the north and the Santa Monica mountains with their extension, the Channel islands, on the south. Both of these ranges trend east and west. The Ventura basin and the mountains that bound it are part of a remark-able east-west orogenic unit, which interrupts the pre-vailingly northwest ranges along the Pacific Coast.

Jan 10, 1927

By H. W. Bell

There was considerable prospecting for new supplies of oil in Arkansas during the past year, regardless of the overproduction affecting the industry throughout the country. Justification for this new work was not lacking, as the local markets more than threatened to absorb a declining production. There were, however, no important new discoveries in the state during 1929. The McDonald area in sec. 2515, S.-18 W., threatened to expand into a major producing area. Oil showings had been encountered here in wells drilled by the McDonald Oil Corpn. as early as the fall of 1928. In July, 1929, an initial production of 1000 bbl. of 32" oil was obtained in McDonald Bros. B-3 Wilson, from a sand at 2780 to 2786 ft., which is about 80 ft. higher than the sand previously tested in the neighboring wells. This production declined rapidly. At the end of the year there were six producers making about 200 bbl. per day total. Seven dry holes have temporarily stopped development in that area. The showing of B-3 was sufficient to cause considerable leasing activity. The area lies several miles west of the Louann portion of the Smackover field. The discovery well went to 2873 ft. and found Glen Rose lime in bottom. The age of the producing sand is in doubt; it seems closely related to the Tokio sand. During 1929, several paying wells were brought in, as a northeastern extension to the Smackover Heavy area, in sec. 34 and 35-15-15, from the Nacatoch sand. Over 20 new wells were drilled and resulted in at least 1500 bbl. production. The down-dip or off-structure territory contiguous to the Smackover uplift was further tested at various locations with the usual results; that is, a showing of "salt water gas," which soon blew off and in some cases a slight showing of oil. These gas showings, found further down the dip than oil, are the results of the ability of water to take gas into solution at the rate of about 3 per cent. by volume at atmospheric pressure and proportionally larger quantities, if available, at higher pressures (measured on the absolute scale). During the year no off-structure wrinkles sufficient to trap conlmercial quantities of oil have been found outside of the other known fields of

Jan 1, 1930