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By W. J. Reagan

MANY factors enter into the manufacture of basic open-hearth steel of high quality. Perhaps the two most important are temperature and the iron oxide content of the metal. If we can control these two factors we can essentially control basic open-hearth practice. SOURCE AND EFFECT OF IRON OXIDE Earlier investigators, especially Herty and his associates, have shown that iron oxide is introduced into the open-hearth furnace in four ways:1 1. - By oxidation of the scrap by furnace gases. 2. By decomposition of the limestone. 3. By oxidation of the iron oxide in the slag by furnace gases. 4. By direct addition of iron ore to the charge. We also know that the speed of operation of an open-hearth furnace depends, for a given charge and given combustion conditions, on the rate at which iron oxide will diffuse from the slag into the metal. The rate of diffusion depends upon a number of variables, such as iron oxide content of the slag, slag viscosity, etc., which also depend upon the amount of iron oxide in the metal, amount of carbon present, temperature, and so forth. For a given carbon and a given temperature, the iron oxide content of the metal is in proportion to the iron oxide content of the slag. This fact can be easily verified by analysis of slag samples taken as described by Herty.2 It is preferable to take these samples just before deoxidation. In killing the steel samples with aluminum it is desirable to use aluminum rod of 99 per cent purity; ordinary commercial aluminum rod with a purity of approximately 92 per cent is not satisfactory. In drilling these samples it is also essential to take the largest amount of drillings possible. This gives more accurate results because it eliminates spotty segregation of Al203.

Jan 1, 1932

By J. L. Gregg

A study of copper-base and silver-base alloys was made with the object of finding, if possible, useful alloys subject to dispersion hardening. These studies led to the discovery of several alloys showing considerable dispersion hardening, the most important of which, the alloys of copper with iron, nickel, cobalt and chromium silicides, have since been very ably reported by M. G. Corson.l This paper is offered as a few notes covering alloys other than those described by Corson and some further data on the silicide alloys. Copper Alloys For the purpose of making a rapid survey of copper alloys that might show useful dispersion-hardening phenomena, various alloys were prepared containing 3 per cent. of additional elements added in such proportion that possible compounds could be formed without an excess of either added element. These alloys in the form of rolled or forged pieces were quenched in water from a temperature of 871" C. (1800" F.) and subsequently aged at various lower temperatures for l-hr. periods. The comparison of the Rockwell hardness of the quenched alloys with the maximum hardness of the alloys after aging was used as a measure of the dispersion hardening. Table 1 shows the Rockwell "E" hardness 1/8-in. ball, 100-kg. load) of the quenched alloys, together with the maximum hardness resulting from aging. The reheating temperature given in this table is the aging temperature at which maximum hardness resulted from a l-hr. sojourn. From this table it may be observed that only the silicide alloys showed significant dispersion hardening. Of these, the only one not described by Corson is the Cu-Be-Si alloy. This alloy contained 1.35 per cent. beryllium and 1.78 per cent. silicon, which is approximately equivalent to 3 per cent. Be2Si. It had a yellow color and scaled much less than the other silicide alloys upon heating. It could be worked easily either hot or cold but hardened very rapidly on cold working. The annealed alloy upon drawing from a diameter

Jan 1, 1929

By J. L. Gregg

A study of copper-base and silver-base alloys was made with the object of finding, if possible, useful alloys subject to dispersion hardening. These studies led to the discovery of several alloys showing considerable dispersion hardening, the most important of which, the alloys of copper with iron, nickel, cobalt and chromium silicides, have since been very ably reported by M. G. Corson.l This paper is offered as a few notes covering alloys other than those described by Corson and some further data on the silicide alloys. Copper Alloys For the purpose of making a rapid survey of copper alloys that might show useful dispersion-hardening phenomena, various alloys were prepared containing 3 per cent. of additional elements added in such proportion that possible compounds could be formed without an excess of either added element. These alloys in the form of rolled or forged pieces were quenched in water from a temperature of 871" C. (1800" F.) and subsequently aged at various lower temperatures for l-hr. periods. The comparison of the Rockwell hardness of the quenched alloys with the maximum hardness of the alloys after aging was used as a measure of the dispersion hardening. Table 1 shows the Rockwell "E" hardness 1/8-in. ball, 100-kg. load) of the quenched alloys, together with the maximum hardness resulting from aging. The reheating temperature given in this table is the aging temperature at which maximum hardness resulted from a l-hr. sojourn. From this table it may be observed that only the silicide alloys showed significant dispersion hardening. Of these, the only one not described by Corson is the Cu-Be-Si alloy. This alloy contained 1.35 per cent. beryllium and 1.78 per cent. silicon, which is approximately equivalent to 3 per cent. Be2Si. It had a yellow color and scaled much less than the other silicide alloys upon heating. It could be worked easily either hot or cold but hardened very rapidly on cold working. The annealed alloy upon drawing from a diameter

Jan 1, 1929

By C. van der Poel

When oil is displaced from a horizontal formation by another fluid of lower density, the latter tends to override the former in the shape of a tongue owing to gravity segregation. This gravity tongue has an adverse influence on the oil recovery. If the fluids are miscible, diffusion (mixing) takes place at the interfacial boundary of the gravity tongue. This mixing should have a favorable effect on oil recovery. The report describes a laboratory study of the magnitude of the mixing zone under various conditions, so as to assess the effect of diffusion on oil recovery both in laboratory experiments and under actual field conditions. The technique used enables visual observation and measurement of the size of the mixing zone in transparent glass-powder packs. The results show that in experiments in small models and cores the width of the mixing zone may well be of the same order of magnitude as the height of the model. In such cases oil recovery is favorably affected by mixing. It can further be concluded that, under conditions prevailing in the field, mixing of the injected fluid with reservoir oil is equal to that caused by molecular diffusion alone, eddy-mixing not taking place to any appreciable extent. A simple calculation, then, shows that molecular diffusion is too small for a beneficial effect to be expected from the injection of miscible fluids in horizontal or nearly horizontal reservoirs unless pay zones are thin. INTRODUCTION This paper gives results of experiments made on the mixing which occurs when a miscible displacement is carried out in a horizontal reservoir. This mixing takes place at the interfacial boundary of the gravity tongue formed when the lighter injected fluid overrides the oil present in the reservoir. The object of the experiments was to simulate the field case where, for example, propane with a viscosity of 0.075 cp under reservoir conditions displaces an oil of viscosity 0.6 cp. In the experiments the lighter fluid had a viscosity of about 1 cp and the heavier one a viscosity of about 8 cp, so as to obtain the same viscosity ratio. In order to enable the results to be compared with those published in the literature, a set of experiments with viscosity ratio equal to one was also performed. EXPERIMENTAL TECHNIQUE The technique developed for the purpose enables the width of the mixing zone to be studied as a function of time and place. A glass-powder pack is saturated with a water-glycerine mixture of suitable viscosity, which represents the reservoir fluid. The pack is then rendered transparent by dissolving sufficient ammonium thiocyanate in the mixture to obtain a solution with a refractive index matching that of the glass powder. Alkaline water to which phenol-phthalein has been added is used as the lighter and less-viscous displacing fluid. In those places where mixing or diffusion of the two liquids occurs, the slightly acidic ammonium-thiocyanate solution neutralizes the alkali in the water, and the glass pack shows up white against the red-colored invading water. If a black cloth is hung over the back of the apparatus, the transparent part of the glass pack appears black. In this way the position of the two phases and the transition zone between them is clearly visible, as shown in Fig. 1 (where the red-colored invading water is the grey-shaded zone lying uppermost). In all experiments the amount of alkali in the water was chosen such that the upper contour corresponded to a concentration of 5 per cent of the dense liquid. The lower contour is determined by the size of the glass grains and the thickness of the pack and, consequently, varies from experiment to experiment. Corresponding concentrations of the dense liquid range from about 97 per cent for packs of small grain size (permeability = 1 darcy) to about 95 per cent for those with large grains

By P. G. Shewmon

A novel technique for determining the surface energy (?) and its derivative with respect to orientation, (?') is described. Essentially it involves the 'floating" of a wedge on the substrate, said wedge being made of a material which is not wet or only slightly wet by the substrate, i. e., as a greased needle "floats" on water. A thermodynamic analysis of a system in which the wedge is supported entirely by surface energy is given. If the original suyface is not at a cusp orientation, the surface tension is directly measurable from the groove angle formed. If the original surface is at a cusp orientation, there may or may not be a groove depending on the relative value of ?' and the weight of the wedge. Experiments primarily on copper and silver showed that sapphire, quartz and refractory metal wedges were wet while graphite wedges were not. The technique was demonstrated to work using graphite wedges, but the results obtained were not as eccurate as those obtained by other workers using the wire-creep experiments. It is concluded that the technique might prove most useful with non-metals where ?' is large and filament creep experiments would be quite difficult. If an absolute value of the surface free energy (?) of a metal is to be determined, the most reliable methods used to date measure an average over the various orientations exposed on a polycrystalline sample. For example, ? for silver, gold, and copper have been measured by determining the force required to just keep a thin wire,' or foil,' specimen from contracting under the influence of ?. Herring 3 has predicted and experiment confirms, that the sensitivity of this method is inversely proportional to the grain size.' Thus it cannot be used to measure ? for a particular orientation by using a foil single crystal or a very coarse-grained specimen. An accurate value if ? for tungsten averaged over a range of orientations has been determined using a field emission technique. The same techniques cannot or have not been used to measure ? for non-metallic solids, and as a result the values available are much less accurate.4 This Paper resents a means of making an absolute determination of ? for a particular surface orientation on any solid, as long as the given surface orientation does not break up into other orientations during an anneal. Experimentally ? is found to vary with orientation and at a few low index orientations it is found to have a cusped minimum, i.e., the derivative of ? with respect to the orientation of the surface changes discontinuously at the low index orientation, see Fig. 1. The slope of a plot of ? vs orientation (herein designated ?') is called the torque on the surface, since it tends to rotate the exposed surface toward the low index orientation, or if the surface is at the cusp orientation it opposes any force tending to rotate the surface out of the low index orientation. The ratio ?'/? has been determined for a few metals, but in cases where this ratio is high there is presently no means of determining either ?'/? or the absolute value of ?' for the orientations present on an annealed surface. The technique discussed herein also provides a means of determining an absolute value of ?' for those orientations which deviate only infinitesimally from a cusp orientation. It should work best on surfaces where ?'/? is large; that is, for cases where no other technique is available for measuring ?'. Aside from trying to learn more about surfaces through measuring ? and ?', the primary reason for wanting values of ? or ?' is to study adsorption. From measurements of the variation of ? for a particular orientation with the concentration of an impurity, one can obtain the number of impurity atoms adsorbed per unit area (Ti) on that orientation using the Gibbs adsorption equation.' where µi is the chemical potential of the adsorbed impurity. Thus, if absolute values of ? could be obtained for the free surface of a given surface orientation as a function of µi, ri could be determined for the given orientation. Furthermore, by equilibrating a grain boundary with the given surface at various values of ki, one could also determine ri for the grain boundary. Similarly Robertson 6 has pointed out that if y is taken to be a continuous function of and µi, then a2 ?/a @a µ2 = a2 ?/a pi a +. Thus, at all orientations away from cusps the following equation holds From a measurement of ?' vs ki, it is thus possible

Jan 1, 1963

By T. F. Witherbee

The following calculation of heat requirement covers the working of the furnace from January 25th to February 14th, inclusive. A short time previous to the first date the furnace had been working rather badly, so that 300 lbs. of ore and 500 lbs. of limestone were taken off. Within the time mentioned the quality of the iron passed

By John A. Church

AT a time when the treatment of gold and silver ore9 by fusion, in opposition to the mill-process, is attracting so much attention in this country, it may be useful to consider what is done in a well-conducted foreign work. For this purpose I will ask the reader to accompany me to Lend, in Austria, a small but thoroughly organized

For the convenience of members who may be traveling from place to place, the Secretary has compiled a list of libraries or other places in the United States and foreign countries where MINING AND METALLURWGY or the Transactions may be consulted. This list will be sent to members if they so request.

Jan 1, 1925

The October issues* of the Journals of the three AIME Societies carried a brief resume of the historical development of various technical and professional organizations which in some immediate or remote way affect the individual member of AIME. This resume was presented by the Institute Committee on Inter-Engineering Society Cooperation. Recently, several plans have evolved designed as a first step to provide a so-called "unity organization" for the entire engineering profession. Almost all of the plans involve Engineers' Joint Council, Engineers' Council for Professional Development, and National Society for Professional Engineers in some way or other. Hence our committee is presenting to our membership a resume of the recent activities of the two umbrella organizations and of NSPE. More detailed information on any of these organizations may be obtained from annual reports published by the organizations.

Jan 2, 1961

By T. Egleston

There has alrvays been atheory among those working placer mines that gold is both folind rusty," and becomes so under treatment, hy which they nleun, not that gold becomes coated with oxide: of gold, but that it, is either coated superficially or alloyed with some substsnee which prevents the contact with mercury,and thus precludenthe possibility of amtrlgamation. To such aoiiditions of the

Jan 1, 1881

By D. E. Etter, J. E. Selle

HIGH-PURITY cerium metals, supplied as 99.9 pct pure, by various suppliers, vary widely in melting points and in the shapes of the differential thermal-analysis curves obtained as the samples are heated. A definite correlation is noted between the melting point, amount of premelting, and the number of inclusions present in the material. Briefly, the DTA apparatus, previously de-

Jan 1, 1964

By J. Farkas

A techno-economic assessment for the recovery of several elements from seawater is presented. Gold recovery has been used as an illustration for the economic evaluation of several processes. Current technology does not present any economically viable alternative to recover gold from seawater because its concentration is several magnitudes too low. However, with the increasingly larger availability of concentrated seawater, mainly from desalination and other processes, coupled with advances in technology, especially genetically modified specific microorganisms, may make the recovery of gold and other desired elements from seawater a reality in the near future.

Jan 1, 1984

By N. Brown, J. Washburn, E. R. Parker

MOST previous quantitative work on creep of single crystals has been concerned primarily with developing empirical equations for the creep curve. Although the equations used by Cottrell and Aytekin¹ and Tyndall² represented the data quite well, it was often necessary to use different values of the constants for different specimens even though they were apparently tested under identical conditions. In the course of previous work on the effect of surface coatings on creep of zinc single crystals," it was found that equal resolved shear stress frequently did not produce equal creep rates in different specimens. The work of Chalmers' in the very

Jan 1, 1954

By Guy R. Johnson

In view of the attention now directed to the development of the iron-ores of Virginia, and of the frequent reference in the Transactions of the Institute to the Longdale mines, it is presumed that a brief account of the methods of working and surveying these mines will be of interest. For a better understanding of such a description, a few words will be said concerning the geological character of the ore-deposit. Professor Rogers says in his preliminary report of 1835, that this deposit has " more of the character of a true vein than is usually

Jan 1, 1892

By AIME AIME

[SECRETARY'S NOTE.-Since the Committee on Publication of United Engineering Society, will issue a memorial volume re¬porting these proceedings in full, an outline only will be here given. The sessions were held in the Main Auditorium.¬R. W. R.] COMMITTEES. EXECUTIVE.-J. W. Lieb, Jr., Chairman; C. W. Rice, Secretary; John Hays Hammond, Chas. Wallace Hunt, F. R. Hutton, Charles Kirchhoff, T. C. Martin, E. E. Olcott, Chas. F. Scott, Samuel Sheldon, Ambrose Swasey. INVITATIONS.-R. W. Raymond, Chairman; Charles Kirchhoff, Secretary; A; C. Humphreys, Robert W. Hunt, L. B. Stillwell. PROGRAM.-A. R. Ledoux, Chairman; C. W. Rice, Secretary; Theodore Dwight, Chas. Wallace Hunt, T. C. Martin, Ralph W. Pope, Joseph Struthers. WAYS AND MEANS.-James Douglas, Chairman A. R. Ledoux, Secretary; H. R. Brown, J.-M. Dodge, C. L. Edgar, John Hays Hammond, W. M. McFarland, E. E. Olcott, Samuel Sheldon, J. G. White. HISTORICAL AND PUBLICATION PRESS.-T. C. Martin, Chairman; Albert Spies, H. H. Suplee.

May 1, 1907

Today, the employment of the modern hammer drill, using hollow steel, with air or water to expel the cuttings from the drill hole, is the rule rather than the exception in practically all rock-drilling operations. There is considerable carelessness in the matter of keeping the hole in the drill steel properly opened. Plugged steels wholly or partially, prevent proper operation of the drill, whereby drilling speed is retarded, water tubes are bent or broken, and time is lost in tink-ering, or, as often happens, the drilling gang is idle while someone makes a trip to the shop after another drill steel or water tube. To relieve this condition, the Ingersoll-Rand Company has developed, as an auxiliary to the Leyner sharpener, a new device-the Leyner shank and bit punch.

Jan 4, 1918

By J. L. Rodda

A large amount of time has been devoted to the microscopical study of the copper-zinc alloys, emphasis naturally being placed upon the commercially important alloys of the system. Suitable methods are available for microscopically recognizing the two phases richest in copper, Per cent,by weight FIG. 1.-COPPER-ZINC EQUILIBRIUM DIAGRAM. (Frond National Metals Handbook, 1933.) but none appear to have been developed for the positive identification of the other phases. This is, however, accomplished, for the phases normally encountered, by an electrolytic method described in the following pages. Five phases of the copper-zinc diagram (Fig. 1) are considered for the purpose of this paper: the solid solution of zinc in copper, alpha (a); the intermediate phases, beta (ß), gamma (y), and epsilon (e); and the solid solution of copper in zinc, eta (n). Beta prime is not considered a separate

Jan 1, 1936

By H. I. Aaronson

THE TTT-curve for the beginning of transformation in hypoeutectoid steels containing appreciable amounts of relatively strong carbide-forming alloying elements often exhibits a "bay" at intermediate temperatures. In many of these steels, proeutectoid ferrite is the initial product of the decomposition of austenite not only at temperatures above the bay but also in an appreciable temperature range below the region of the bay. Hultgren has postulated that ferrite formed above the bay, termed "orthoferrite", contains the equilibrium concentration of alloying element at temperatures above the eutectoid range, and the extrapolated metastable equilibrium concentration at lower temperatures. The ferrite formed below the bay, on the other hand, termed "paraferrite", was assumed to inherit completely the bulk alloy content of the austenite without regard for the compositional requirements of equilibrium. As shown schematically in Fig. 1, the two types of ferrite were taken to have different Ae3 temperatures and different C-curves on a TTT-diagram. Their different kinetic behaviors were thus considered responsible for the bay in the TTT-curve for the proeutectoid ferrite reaction in this type of alloy steel.

Jan 1, 1962

By J. E. Dorn

A STUDY of the increase in density of copper powder as as a function of the time and temperature of sintering has been previously reported.' The present note will describe the results of a series of experiments under conditions similar in all respects to those of the first series, except that

Jan 1, 1951

By D. J. Mack, J. A. Mullendore

MUCH work has been reported in the literature on the separation of individual phases in steels, particularly carbides, for the purpose of structural and chemical analysis. The methods usually involve separation of the particles from the matrix by chemical or electrochemical methods. Another .group of alloys ideally suited for selective removal of one phase is the commercial aluminum bronzes. Al-

Jan 1, 1959