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Institute of Metals - Iron and Steel - Mineral Industry - Industrial Minerals Year ?Division - Petroleum Division ? Division - Coal Division - Education Division -Division 1918 W M CORSE 1919 1920 W. H BASSETT 1921 1922 W B PRICE RALPH ARNOLD 1923 E DEGOLYER 1924 G K ELLIOTT 1925 F JULIUS FOHS 1926 PAUL D MERICA 1927 JOHN M LOvEJOY 1928 S SKOWRONSKI A W AMBROSE RALPH H SWEETSER

Jan 1, 1952

By William Metcalf

One of the first questions that naturally occurs to one who handles steel is, " Why does steel harden?" To answer this question the chemist and physicist have devoted much thought and experiment, and while they have enriched our store of knowledge of the nature and composition of steel, it cannot be said that they have yet solved the problem involved in its hardening. In this communication I desire to direct attention to a line of investigation yet new, in the hope that it may receive the attention. of those who have the time and ability to pursue it. I refer to magnetism. There are so many parallels between the action of magnetism on iron and steel and their behavior under different processes of manipulation that it would seem. as if there must be some connection between tile forces at work in the different cases, if, indeed, there be not an identify of force in all of these cases. Magnetism, as me know it, may be merely the visible manifestation of forces, which may serve as a guide to lead us to an exact knowledge of the structure, tile strains, and the resistances with which me have to deal in iron and steel. If a magnet be brought close to a pile of iron filings, the little pieces of iron will fly to the maguet and attach themselves to it, with their longer axes lying in the direction of the force. If molten cast iron be poured into an iron mould,—a chill,—the iron upon crystallizing will form needlelike crystals, with their long axes normal to the surfaces of the mould. • If the iron is at the proper temperatare and the quantity small, compared to the mass of the mould, the whole of it, will be chilled, or set, in 'the hard needlelike crystals

Jan 1, 1881

By Bernt Ellingsaeter, Terkel Rosenqvist

IN the silicothermic reduction of magnesia, burned dolomite is treated with high grade ferrosilicon in an evacuated steel retort at temperatures between 1150° and 1200°C. The following reaction is assumed to occur MgO + CaO + 1/2 Si (Fe) - Mg(g) +- & Ca,SiO, + Fe with the equilibrium constant on the basis of thermodynamic data for the substances involved and assuming unit activity for all solid constituents, Kubaschewski and Evans' calculated the magnesium pressure as a function of temperature logp,, (mmHg) = 15.06-1.61 T- log T- 13,16O/T. Pidgeon and King," who measured the magnesium pressure by means of a flow method, found values about three times the calculated ones. This may be caused by uncertainties in the thermodynamic data, but may also be caused by the formation of other reaction products, such as Ca,SiO,, which is known to be the stable silicate in equilibrium with lime. Whatever the exact reaction may be, it is evident that as long as all other factors are maintained constant the magnesium pressure will vary with the silicon activity, viz: p,, = &,. (p,,) ", where (p,,)" is the magnesium pressure by the reduction with silicon of unit activity. In the present investigation, p,,, was therefore measured for various grades of ferrosilicon and their silicon activities were calculated. The experimental method was similar to that used by Pidgeon and King. Briquettes of burned dolomite and Fe-Si alloys were placed in a 1 in. heat resistant steel tube and were heated to 1200°C. By means of a flow of purified hydrogen, the magnesium vapor was swept into a condenser filled with steel wool. From the amounts of hydrogen used and magnesium condensed the magnesium partial pressure was calculated. First a tube of 28 pct Cr steel, and later a tube of Kanthal D (a ferrous alloy with 22.6 pct Cr, 2 pct Co, and 4.5 pct Al), was used as a heat resistant tube. The latter tube showed the best heat resistance. The dolomite used had the following composition: 43.6 pct MgO, 55.5 pct CaO, 0.2 pct K,O + NalO, 0.2 pct Fe,O,, and 0.3 pct insoluble. The ferrosilicons were prepared from 98 pct Si of technical grade (0.7 pct Al, 0.3 pct Ca, and 1 pct Fe) by melting with various amounts of electrolytic iron of high purity. The alloys thus obtained were analyzed on their iron and silicon contents, which added up to between 99 and 100 pct. The amounts of reactants were chosen so that there would always be an excess of the oxides, and the average decrease in silicon content during the experiments would be about 1 pct. Most of the reaction occurred in the part of the reaction mixture facing the gas flow. The change in the silicon concentration in the part facing the condenser was, therefore, negligible. To facilitate the reaction, about 1 pct fluorspar was added to the briquette mixture. Fluorspar does not enter the reaction, but is known to act as a

Jan 1, 1957

By J. T. Williams

The equilibria in the V-Zr alloy system were investigated by solidus temperature determinations, thermal analysis, dilatometry, electrical resistance measurements, microscopic examination, and X-ray diffraction analysis. There is a eutectic reaction at 1230°C between a compound, V2Zr, and a solid solution containing 10 pct V in ß zirconium. V2Zr decomposes at 1300°C into liquid and a solid solution containing about 10 pct Zr in vanadium. The eutectic composition is probably about 30 pct V. A eutectoid reaction between V2 Zr and a zirconium takes place at 777°C at a very high rate. The eutectoid composition is 5 wt pct V. The limit of solubility of zirconium in vanadium was estimated to be 5 pct at 600°C. No attempt was made to determine the liquidus for the system. THE recent availability of large quantities of high purity zirconium has stimulated the study of zirconium binary systems. The equilibrium diagram for the V-Zr system has received little attention, however. Wallbauml appears to have made the first report concerning the equilibria in these alloys. He reported the existence of a compound, V2Zr, having the MgZn2 ((214) type of structure with a, = 5.277 kX and c° = 8.647 kX. Anderson, Hayes, Roberson, and Kroll2 made a survey of some potentially useful zirconium binary alloys and found that zirconium probably dissolves a small amount of vanadium. They reported the probable existence of a compound between the two elements and suggested that the zirconium-rich solid solution undergoes a eutectic reaction with this compound. Pfeil," in a critical review of the existing information, estimated that the solubility of vanadium in zirconium is less than 4.7 pct and probably less than 1.8 pct. Rostoker and Yamamoto' proposed a partial diagram for the V-Zr system in a survey paper on vanadium binary alloys. Their diagram indicates the compound, V,Zr, a eutectic reaction at 1360°C, a peritectic reaction at 1740°C, and a limit of solubility of zirconium in vanadium of about 3 pct. They obtained no information on the equilibria in the zirconium-rich alloys. In view of the potential utility of the V-Zr alloys and the incomplete knowledge concerning the equilibria in the system, an attempt was made to establish the constitutional diagram. Preparation of the Alloys Raw Materials: The vanadium for making up these alloys came from the Electro Metallurgical Corp. Zirconium came from two sources. In the beginning of the investigation, sponge zirconium from the Bureau of Mines was used in making some of the alloys. Later, iodide metal made at the Westinghouse Atomic Power Development Laboratories became available. This material was used in the preparation of all the dilatometric and resistance specimens and about two-thirds of the solidus temperature specimens. A typical manufacturer's analysis of the vanadium is shown in Table I. No other analysis of the vanadium was made. The metal contained a dispersed second phase and did not have a sharp melting point. Typical results of spectrographic analysis of the Westinghouse zirconium are shown in Table 11. These data indicate a very high purity. The Bureau of Mines sponge metal was probably less pure but had good ductility. Melting: All of the alloys used in the investigation were made by melting pieces of vanadium and zirconium together in a dc electric arc furnace similar to those of Geach and Summers-Smith, craighead, Simmons, and Eastwood," and others. Melting was done in an atmosphere of helium scavenged of residual air by the preliminary melting of a separate charge of zirconium. Each ingot was turned over and melted at least three more times before removal from the furnace to aid in the attainment of homogeneity. Alloys prepared for use in the investigation are listed with the results of solidus determinations in Table III with the exception of the following compositions upon which no solidus determinations were made: 0.29, 0.54, 4.57, and 5.55 pct V. Analysis: The weight of each ingot made from iodide zirconium was within 0.1 g of the total weight of the initial charge, about 90 g. Since each component of each charge was weighed to the nearest 20 mg for amounts less than 10 g and to the nearest 0.1 g otherwise, the gross composition of an ingot could be calculated accurately. Chemical analysis for the vanadium content of several alloys agreed

Jan 1, 1956

By R. M. Hudson

Equilibrium constants have been determined for the jeaction C (in steel) + H2O = CO + H2 as a function of carbon content (0.013 to 0.74 ujt pct) and temperature (1200° to 1800°F) by using a flow system in which the water-vapor content of various gas mixtures containing hydrogen, carbon monoxide, and nitrogen was systematically controlled. The equilibrium partial-pressure ratio K1 = PcoPH2/PH2O was obtained for two low-carbon steels and four Fe-C binaries from a series of runs made at each temperature. By comparison of Ki with the analogous ratio for the reaction C (graphite) + H2O = CO + H2, the activity of carbon in steel (ac) was comDuted for each temperature and carbon content studied. From these data values of the equilibrium constants for two other carburization-decarburiza-tion reactions of importance were estimated. The chemical compositions of the two steels and four Fe-C binaries used are given in Table I. Specimens of Steel E were cut from a 0.035-in.-thick commercially box-annealed and temper-rolled lot of a low-carbon low-metalloid steel. Steel F was a commercially hot-rolled rimmed steel that was cold-reduced at the Laboratory to a 0.059-in. thickness. Fe-C binaries A, B, C, and D were vacuum-melted and poured, hot-rolled, pickled, and cold-reduced at the Laboratory to furnish specimens 0.035 in. thick. Sheet specimens were cut from all lots to approximately 3/4 by 3 in. by gage and were vapor-degreased with trichlo-roethylene and weighed before heat treatment. Heat treatments were carried out in a hinged-top Hevi-Duty electric furnace with a Vycor-glass tube. When the furnace was at the desired

Jan 1, 1965

By G. R. Leverant, C. P. Sullivan

To evaluate the effect of a dispersion of nondeform-able, incoherent, second-phase particles on high-strain cyclic deformation and fracture, recrystallized TD-nickel (Ni-2ThO2) and a commercially pure nickel, Ni-200, were fatigued under strain control at total strain ranges varying from 0.009 to 0.036. Relative to the Ni-200, the slip at the surface of the TD-nickel was more wavy and discontinuous due to the presence of the thoria particles. This made crevice formation (incipient cracking) within slip bands more difficult in TD-nickel than in Ni-200. Both materials cyclically hardened to a constant (saturation) flow stress which increased with increasing plastic strain amplitude. Cellular substructures were developed in both materials during cycling. The cell size in TD-nickel was controlled by the thoria particle distribution and was independent of plastic strain amplitude over the range investigated. The cell size in Ni-ZOO was larger than that in TD-nickel at similar plastic strain amplitudes and was a function of plastic strain amplitude. These results, together with the cyclic stress-strain curves for both materials, are discussed in terms of a model for fatigue strain accommodation at saturation recently proposed by Feltner and Laird. NUMEROUS fatigue investigations have considered the interrelation of slip character, dislocation substructure, and cracking in pure metals and solid-solution alloys. However, except for the studies of the low-strain fatigue of internally oxidized copper alloys1 and cast, dispersion-strengthened lead,&apos; little is known about the effects which small, incoherent, nondeform-able, second-phase particles have on cyclic deformation and cracking processes. Effects due to the particles alone are often obscured by a dislocation substructure introduced during thermomechanical processing of dispersion-strengthened metals. In the present study, recrystallized TD-nickel and a commercially pure nickel, Ni-200, were employed to evaluate the effect of a thoria dispersion on high-strai fatigue deformation and cracking at room temperature. I) MATERIAL AND EXPERIMENTAL PROCEDURE The TD-nickel was supplied by DuPont as a 5/8-in.-thick stress-relieved plate which had been subjected to a proprietary schedule of thermomechanical treatments, and the Ni-200 as 3/4-in. bar which was subsequently annealed for 2 hr at 850°C in argon resulting in an average grain diameter of 0.05 mm. The compositions of these materials are given in Table I. The microstructure of the TD-nickel consisted of elongated grains parallel to the primary working direction with an average width of 0.16 mm, Fig. l(a). Many fine annealing twins were present indicating that the starting material was in a recrystallized condition; this supposition was confirmed by the absence of of any extensive dislocation substructure, Fig. l(b). Sheetlike stringers parallel to the rolling direction were occasionally seen both within grains and at grain boundaries. Some approximately spherical particles about 2 in diam, which may correspond to exceptionally large thoria particle aggregates, were also present. The average Young&apos;s modulus of the plate material in the rolling direction was 21.8 X 106 psi which is consistent with a {100}<001>recrystalliza-tion texture3&apos;* being prominent. In transmission microscopy, the 2.3 vol pct of thoria particles generally appeared to be uniformly distributed although some clusters, 0.1 to 0.3 in diam, of larger particles were observed as previously reported for TD-nickel sheet,5 and stringering of particles was present in some areas as welt. The average diameter of the thoria particles was 450A with a calculated mean planar center-to-center spacing of 2100A, as determined by quantitative metallographic analysis.= The 0.2 pct offset yield stress was 36,000 psi which agrees with the value predicted by the modified Orowan relation7 for edge dislocations bowing between thoria particles of the size and spacing observed in the present investigation. Fig. 2 illustrates the specimen design employed for the axial high-strain fatigue testing. Adapters were screwed onto the threaded portions of each specimen so that testing could be performed in the same manner as that reported for buttonhead specimens.8 Stressing was coincident with the working direction for both materials. The gage section of each specimen was electropolished and lightly etched prior to testing. The total strain was controlled, being varied between zero and a maximum tensile strain ranging from 0.009 to 0.036. In addition to these tests, a circum-ferentially notched TD-nickel specimen was cycled over a total strain range of 0.0075. The same strain

Jan 1, 1969

By Paul Averitt

The U. S. Geological Survey has been actively engaged in work on coal for more than 50 years. During this long period we have released more than 300 publications containing information about coal and coal reserves, including details on the thickness, distribution, and quality of coal, and the structure and stratigraphy of the coal-bearing rocks. We have also cooperated with state surveys on many similar publications. For many areas these reports are the only reliable published data on our resources of coal. During the last several years we have substantially increased our activities above the wartime low. We now have field work in progress, or reports in preparation, on 13 detailed mapping projects distributed as follows: 1. Pennsylvania anthracite field 2. Casselrnan Basin, Md. 3. Leslie County, Ky. 4. Deep River field, N. C. 5. Coosa field, Ala. 6. Powder River field, Mont. 7. Spotted Horse field, Wyo. 8. Yampa field, Colo. 9. Paonia field, Colo. 10. Trinidad field, Colo. 11. Durango field, Colo.

Jan 1, 1949

By J. S. Brown, A. G. Guy

With the exception of the work of Tammann and Hartmann,1 no published information has been found on the structural changes produced in eutectic structures as the result of heating following plastic deformation. In part this lack of information may be due to the fact that many eutectic structures contain an intermetallic compound as a prominent phase, and as a consequence have been considered to be unworkable. For example, Tammann and Hartmann were able to obtain useful data only on those alloys that they could greatly reduce in thickness by cold rolling. This restriction placed on the investigation of alloys containing intermetallic compounds has been largely removed by the work of Savitskii2 which showed that large deformations of such alloys can be produced by relatively slow compression at temperatures near the melting range. It was possible, therefore, to carry out the present work on a range of binary eutectics including one composed of two intermetallic compounds. The essential results obtained on the alloy systems studied are illustrated by the Pb-Mg eutectic containing 33.2 pct Mg, Fig 1. The cast structure, Fig la, was obtained by melting together magnesium of 99.8 pct purity and chemically pure test lead, casting into a heated, small steel mold, and furnace cooling in the mold from about the eutectic temperature. The fairly coarse eutectic structure thus obtained was too brittle to work at room temperature without cracking. Fig 16 shows the worked structure obtained by compressing a 1/2-in. cube 70 pct in about 15 sec at 550°F and then water quenching. The pronounced changes in the distribution of the two phases produced by heating the worked alloy at 850°F for 1 hr are shown in Fig lc. Recrystallization of both phases appears to have taken place, and the mechanical properties of the cast alloy must have been significantly changed by the working and heat treatment. Similar results were obtained with the Mg-59.5 pet Bi, Mg-36.4 pet Sn, Mg-65.4 pet Cu, and Bi-40 pet Cd eutectics, only the last of which could be worked at room temperature. Tammann and Hartmann reported a thickening and shortening of the needles of the eutectics which they heated about 10°C below the melting range for 1 hr after drastic cold rolling. They found the following eutectics, given the indicated amounts of reduc- tion, to have a granular structure after heat treatment: Sn-9 pet Zn (98 pet); Cd-82.5 pet Pb (60 pet); and Bi-43.5 pet Pb (90 pet). On the other hand the alloy Al-11.7 pet Si (60 pet) showed no change after heating. Tammann and Hartmann observed a distinct shrinking of the needles in unworked eutectics subjected to heat-treatment. In the present work inappreciable change in the eutectic structure was found on heating undeformed alloys. In summary, it appears that eutectic structures can be recrystallized into a "spheroidized" condition by heating near the eutectic temperature after severe deformation. If the eutectic contains one or more brittle phases the necessary deformation can be accomplished by pressing at high temperatures. It is reasonable to expect that this tendency towards equiaxed grains from the plate- or needle-like eutectic structure should be general since the energy relations and mode of growth in recrystallization are so different from those that hold for eutectic crystallization. References 1. G. Tammann and H. Hartmann: Ztsch. Melallkunde (1937) 29, 141-144. 2. E. M. Savitskii: Doklady Akad. Nauk S.S.S.R. (1940) 62, 349-351. Abstr. in Melal Prog. (July, 1949) 56, 126, 128.

Jan 1, 1950

By L. F. Mondolfo

R301 is a clad aluminum alloy, composed of a core of a duralumin-type alloy clad with a magnesium silicide alloy. It differs from other well-known clad alloys in that the cladding and the core respond to the same heat-treatments. and therefore the cladding contributes appreciably to the mechanical properties of the material. In Table I are reported the compositions of the core and cladding alloy for the material used for the experiments. Table i.—Chemical composition of R~OI Used for the Experiments Element Core Cladding Cu........................ . 0.01 Fe......................... . 0.42 Si......................... 0. 0.71 Mg........................ . 0.99 Mn ........................ . 0.54 In clad aluminum alloys where the core contains copper and the cladding does not, at elevated temperatures the copper tends to diffuse from the core through the cladding. This fact is well known and many investigations have been conducted to determine the features of this diffusion. Most of those investigations cover materials clad with pure aluminum; the present investigation covers a material clad with an alloy. Since the cladding thickness on R~OI varies with the gauge, as shown in Table 2, several gauges were investigated. Material and Procedure he material used was sheet of the following gauges: o.o2~, 0.040, 0.064, 0.102, 0.170 Cut in pieces approximately 3 by 5 in., it was in the cold-rolled state and was soaked for increasing times at the following temperatures: glo°F., 940°F., 970°F. A Lindberg cyclone furnace was used for the experiments. The procedure was as follows: The furnace was started empty with controlling pyrometer set at the determined temperature. After the furnace had reached that temperature, it was run for some 20 to 30 min. empty, in order to allow the temperature inside to become stabilized. Then the first samples were introduced. A load thermocouple, with recording pyrometer, was connected with the sample of the heaviest gauge. About 10 min. was required for the material to reach temperature and the soaking time was counted from that point. After zoo min. soaking, the second group of samples was introduced without stopping the furnace. After 200 min. more, the third group of samples was introduced, and so on, until the last sample had been introduced. Every time the furnace was opened and new samples were added, a drop of temperature was registered by the thermocouple connected with the material

Jan 1, 1946

By L. F. Mondolfo

R301 is a clad aluminum alloy, composed of a core of a duralumin-type alloy clad with a magnesium silicide alloy. It differs from other well-known clad alloys in that the cladding and the core respond to the same heat-treatments. and therefore the cladding contributes appreciably to the mechanical properties of the material. In Table I are reported the compositions of the core and cladding alloy for the material used for the experiments. Table i.—Chemical composition of R~OI Used for the Experiments Element Core Cladding Cu........................ . 0.01 Fe......................... . 0.42 Si......................... 0. 0.71 Mg........................ . 0.99 Mn ........................ . 0.54 In clad aluminum alloys where the core contains copper and the cladding does not, at elevated temperatures the copper tends to diffuse from the core through the cladding. This fact is well known and many investigations have been conducted to determine the features of this diffusion. Most of those investigations cover materials clad with pure aluminum; the present investigation covers a material clad with an alloy. Since the cladding thickness on R~OI varies with the gauge, as shown in Table 2, several gauges were investigated. Material and Procedure he material used was sheet of the following gauges: o.o2~, 0.040, 0.064, 0.102, 0.170 Cut in pieces approximately 3 by 5 in., it was in the cold-rolled state and was soaked for increasing times at the following temperatures: glo°F., 940°F., 970°F. A Lindberg cyclone furnace was used for the experiments. The procedure was as follows: The furnace was started empty with controlling pyrometer set at the determined temperature. After the furnace had reached that temperature, it was run for some 20 to 30 min. empty, in order to allow the temperature inside to become stabilized. Then the first samples were introduced. A load thermocouple, with recording pyrometer, was connected with the sample of the heaviest gauge. About 10 min. was required for the material to reach temperature and the soaking time was counted from that point. After zoo min. soaking, the second group of samples was introduced without stopping the furnace. After 200 min. more, the third group of samples was introduced, and so on, until the last sample had been introduced. Every time the furnace was opened and new samples were added, a drop of temperature was registered by the thermocouple connected with the material

Jan 1, 1946

By Leland L. Mink, Roy E. Williams, Lewis M. McNay, Alfred T. Wallace

In 1968 the metal-mining industry of northern Idaho installed tailings ponds as a means of handling and treating mine wastes, metallurgical process wastes and domestic wastes. The installation of the ponds constituted a crash program to minimize pollution of the Coeur d&apos;Alene River. The ponds provided an opportunity to investigate which combinations of wastes tailings ponds can be treated. The research data pertaining to tailings pond discharge lends insight into compliance with the recent EPA guideline for effluent quality.

Jan 7, 1973

PRESIDENT Willis McGerald Peirce New York City, N Y PAST PRESIDENTS D H McLaughhn, San Francisco, Calif L E Young&apos;, Pittsburgh, Pa VICE-PRESIDENTS A. B. Kinzell, New York, N Y H. W Thomas Ray, Arizona Philip Kraft, New York, N Y J L Gillsan Wilmington, Del M. L Haider, Toronto, Ont , Canada VICE-PRESIDENT and TREASURER Andrew Fletcher, New York, N Y

Jan 1, 1951

By Sage B. H., Lacey W. N., G. W. Billman

The composition of the coexisting phases in the methane-ethane-n-pentane system was determined at 100°F. This was accomplished by withdrawing samples of the coexisting phases under isobaric-isothermal conditions. The relative amount of each of the components present in the liquid and gas phases was determined by conventional analytical fractionation methods. The phase behavior of this system approximates that estimated from generalized correlations which take into account the influence of the nature and amount of each of the components present upon the equilibrium. It was found that for particular pressures and temperatures the equilibrium constant of each of the components was influenced significantly by the composition of the system and this effect was more pronounced at the lower pressures for methane than for the components of greater molecular weight. However, at the higher pressures approaching the maximum two-phase pressure for the system at this temperature the composition markedly influences the equilibrium constants of all the components at a particular pressure and temperature. The results of this study are presented in graphical and tabular form. Introduction The phase behavior of many of the binary systems containing parafin hydrocarbon components from methane through n-pentane has been investigated during recent years. In addition the compositions of the coexisting phases in mixtures of crude oil and natural gas have been studied.&apos; However, these results do not establish the influence of the nature and amount of the other substances making up a multi-component system upon the gas-liquid equilibrium constant of any one component. A preliminary correlation on the basis of values for binary systems was made2 utilizing such experimental information as was available. However, there is need for much additional information regarding behavior in systems containing more than two components. Study of the phase behavior of ternary systems offers a feasible attack upon the determination of the influence of composition as well as of pressure and temperature upon the several equilibrium constants concerned. An investigation of the phase behavior of the methane-propane-n-pentane system at 100°, 160°, and 220°F was reported.".&apos; This work served to illustrate the marked influence of concentration of the other components upon the equilibrium constants. Variations of as much as 50 pct in the equilibrium constants for methane for fixed temperature and pressure were observed in regions remote from the critical state. Likewise there was a marked variation in the equilibrium constants of propane and n-pentane as a result of changes in the composition. These results indicated the desirability of investigating additional ternary systems. The present paper deals with a study of the methane-ethane-n- pen-tane system at 100°F, which is similar in many respects to the work upon the meth-ane-propane-n-pentane system cited above.

Jan 1, 1948

By Sage B. H., G. W. Billman, Lacey W. N.

The composition of the coexisting phases in the methane-ethane-n-pentane system was determined at 100°F. This was accomplished by withdrawing samples of the coexisting phases under isobaric-isothermal conditions. The relative amount of each of the components present in the liquid and gas phases was determined by conventional analytical fractionation methods. The phase behavior of this system approximates that estimated from generalized correlations which take into account the influence of the nature and amount of each of the components present upon the equilibrium. It was found that for particular pressures and temperatures the equilibrium constant of each of the components was influenced significantly by the composition of the system and this effect was more pronounced at the lower pressures for methane than for the components of greater molecular weight. However, at the higher pressures approaching the maximum two-phase pressure for the system at this temperature the composition markedly influences the equilibrium constants of all the components at a particular pressure and temperature. The results of this study are presented in graphical and tabular form. Introduction The phase behavior of many of the binary systems containing parafin hydrocarbon components from methane through n-pentane has been investigated during recent years. In addition the compositions of the coexisting phases in mixtures of crude oil and natural gas have been studied.&apos; However, these results do not establish the influence of the nature and amount of the other substances making up a multi-component system upon the gas-liquid equilibrium constant of any one component. A preliminary correlation on the basis of values for binary systems was made2 utilizing such experimental information as was available. However, there is need for much additional information regarding behavior in systems containing more than two components. Study of the phase behavior of ternary systems offers a feasible attack upon the determination of the influence of composition as well as of pressure and temperature upon the several equilibrium constants concerned. An investigation of the phase behavior of the methane-propane-n-pentane system at 100°, 160°, and 220°F was reported.".&apos; This work served to illustrate the marked influence of concentration of the other components upon the equilibrium constants. Variations of as much as 50 pct in the equilibrium constants for methane for fixed temperature and pressure were observed in regions remote from the critical state. Likewise there was a marked variation in the equilibrium constants of propane and n-pentane as a result of changes in the composition. These results indicated the desirability of investigating additional ternary systems. The present paper deals with a study of the methane-ethane-n- pen-tane system at 100°F, which is similar in many respects to the work upon the meth-ane-propane-n-pentane system cited above.

Jan 1, 1948

By R. F. Miller, R. F. Campbell

Sixteen steels containing different combinations of chromium and molybdenum, in amounts up to 5 per cent of each element, were examined for microstructure and hardness after air cooling and after furnace cooling from suitable austenitizing temper- atures. Diagrams summarizing the structnres and hadness resulting from these two cooling rates are presented (Figs. 3, 4, 7).t Data were also obtained on the influence of these two elements, individually and in combination, on the depth of decarburiza-tion observed after furnace cooling (Fig. 8). Composition of Material The chemical composition of the steels investigated is given in Table I. The plain carbon steel was made in a 2 5-ton Heroult electric-are furnace, while the alloy steels were made in a 4.5-ton Ajax-Northrup elec- tric induction furnace. The cast ingots were hot-rolled to 1.75-in. bars. Air-cooled Series The I.75-in. bars were forged to flat plates, 0.25 in. thick, from which specimens 0.5 in. wide by 2 in. long were cut. The specimens were pretreated to improve their homogeneity by heating to 1830°F. (I000°C.) for 20 min. and oil-quenching. They were then reheated to 1740°F. (950°C.) for one hour and air-cooled, after

Jan 1, 1942

By R. F. Campbell, R. F. Miller

Sixteen steels containing different combinations of chromium and molybdenum, in amounts up to 5 per cent of each element, were examined for microstructure and hardness after air cooling and after furnace cooling from suitable austenitizing temper- atures. Diagrams summarizing the structnres and hadness resulting from these two cooling rates are presented (Figs. 3, 4, 7).t Data were also obtained on the influence of these two elements, individually and in combination, on the depth of decarburiza-tion observed after furnace cooling (Fig. 8). Composition of Material The chemical composition of the steels investigated is given in Table I. The plain carbon steel was made in a 2 5-ton Heroult electric-are furnace, while the alloy steels were made in a 4.5-ton Ajax-Northrup elec- tric induction furnace. The cast ingots were hot-rolled to 1.75-in. bars. Air-cooled Series The I.75-in. bars were forged to flat plates, 0.25 in. thick, from which specimens 0.5 in. wide by 2 in. long were cut. The specimens were pretreated to improve their homogeneity by heating to 1830°F. (I000°C.) for 20 min. and oil-quenching. They were then reheated to 1740°F. (950°C.) for one hour and air-cooled, after

Jan 1, 1942

By B. J. Reid, J. N. Greenwood

It has been shown1 that cavities are formed in the grain-boundaries of copper and 70:30 brass (as well as in magnesium) by the application of tensile stresses at elevated temperatures. For a given rate of strain, cavities are formed in brass at a lower temperature than in copper, and they are larger; it was thought that this earlier onset of cavitation in the alloy might be caused by the distortion produced in the metal lattice by the alloying element. If the cavitation is caused by the vacancy-migration mechanism, &apos; the distortion of the lattice would reduce the energy required for vacancy formation, and thus provide vacancies more readily to assist in the cavitation process. It was decided to study a range of alloys to find out whether increasing amounts of an alloying element would cause any progressive increase in, or modification of, the cavitation in copper. Nickel was chosen for this purpose, since it is soluble in copper throughout the whole range of alloys. A further advantage was its low vapor pressure, which enabled the preparation of the alloys in vacuum and the consequent reduction of their hydrogen content. It has been suggested that cavities may be nucleated by the migration of hydrogen atoms to the less regular atomic spacing at the boundary, and their combination to form molecules. The latter being too large to diffuse back into the lattice, form stable cavities into which vacancies could condense. PREPARATION OF ALLOYS All alloys, ranging from pure OFHC copper to 43.7 at. pct of nickel (carbonyl), were prepared in a vacuum furnace employing high-frequency induction heating. When a charge was melted, vigorous gas evolution occurred initially, after which the pressure was reduced to 10-4 mm Hg, using an oil-diffusion pump. After remaining molten for a further 1/2 to 1 hr to aid degassing, the melt was allowed to solidify in the crucible. In this way contamination by gases evolved from the surface of a separate mold was avoided. The list of alloys prepared is shown in Table I. The percentage of hydrogen present in the OFHC copper was reduced from 0.0054 at. pct to 0.0012 at. pct, as measured by a vacuum-fusion method. The alloys were cold-rolled to 0.03-in.-thick strip, and were homogenized in vacuum for 1 hr at 900°C after every 30 pct reduction. At a thickness of 0.05 in., the strip was held at 450°C for 24 hr under high vacuum (10-5 mm Hg) in an attempt to reduce the hydrogen content still further. Tensile specimens were prepared with a gage length of 1 in., and were finally annealed for 2 hr at 800°C to give an average grain diameter of 0.1 mm. TENSILE DEFORMATION The specimens were deformed in a tensile straining machine operated by a synchronous motor at a constant rate, equivalent to 1.7 pct per hr on a 1-in. gage length. The specimen and grips were contained in a vacuum jacket. A pressure of 10-2 mm Hg was maintained, which was sufficient to prevent surface tarnishing of a specimen held at 650°C for 24 hr. Tests were made between 20. and 650°C and the temperature was controlled to within ±3° over the gage length. The load was measured by the deflection of a cantilever spring. a) Mechanical Properties-The ductility curves shown in Fig. 1 fall into two groups. Figs. 1(a) and (b) for copper and the 5 pct nickel alloy, respectively, show a continuous fall in ductility with a steep fall between 200° and 400°C. Figs. l(c) to (f) show the same sudden loss of ductility between 200° and 400°C. With higher temperatures, however, there is a recovery in ductility values to a maxi-

Jan 1, 1959

By George A. Packard

The experiments here described were made under my supervision while temporarily acting as head of the Department of Metallurgy at the Missouri School of Mines, at Rolla. The work was done by Messrs. W. E. Brown, W. C. Richards, and F. L. L. Wilson, and the description of the results forms a portion of a thesis presented for the degree of Bachelor of Science. These results are submitted because I have seen no description of the application of pot-roasting to the treatment of a copper-concentrate. This work followed that already described in the discussion of the Lime-Roasting of a Galena-Concentrate,&apos; and was similarly occasioned by the lack of a furnace of the reverberatory type in which the copper-concentrates could be smelted. The material for the tests was a mixture of three lots available. The first consisted of 8-mm. ,jig-concentrates and the second of 0.5-mm. table-concentrates, from the San Juan district, Colo. Both contained pyrite, chalcopyrite, and galena. The third was a lot of copper-ore, found in the laboratory, which had been crushed through 8-mm. screen, and had at some previous time, before the laboratory roasting-furnace was torn down, received a partial roasting. The analyses of these ores are given in Table I. In order to determine the applicability of pot-roasting as to each lot of ore, and the effect of varying proportions of lime, six preliminary tests were made in a " size N " Battersea crucible, 9 in. high by 6 in. in diameter at top, with a 5/8-in. hole bored through the bottom. The crucible was set in the upturned elbow of a 2-in. pipe, the joint being luted with clay; and air was obtained from a receiver supplied by a compressor. The

Jan 1, 1908

NORTH AMERICA. CANADA Canadian Army Overseas. Ball, H. D. Bridges. C. Butterill, H. J. If. Ladner, F. E. Lane, H. C. Alillar, W. A. ALBERTA Calgary.-Chonette, W. C. Clark, L. At. Corbett, C. S. de Hart, J. B. Dingman, C. W. Fath. A. E. Fulton. J. If. Cray, J. G. Johnson. R. V. McCutchin, J. A. *Slipper, S. E. Vin Buckirk H. A.

Jan 1, 1944

C. H. MATHEWSON, Chairman SAM TOUR, Past-chairman W. A. SCHEUCH, Vice-chairman T. S. FULLER, Vice-chairman W. M. CORSE, Secretary-Treasurer 810 Eighteenth St., N. W. Washington, D. C. Executive Committee J. L. CHRISTIE ARTHUR PHILLIPS E. H. Dix, JR. GUY C. RIDDELL W. M. PRIRCE J. WALTER SCOTT&apos; A. J. PHILLIPS&apos; H. M. WILLIAMS EL M. WISE

Jan 1, 1932