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By E. T. Peters, L. E. Tanner

In the course of a study concerned with the rnechanical behavior of the intermetallic compound CO3V, both structural observations and anomalous electrical-resistivity behavior indicated the presence of a new high-temperature phase in an alloy with the stoichiometric composition, Co-22.4 wt pet V. The evidence, which is given below, suggests that the new phase is situated between the low-temperature ordered hexagonal phase, k,1, 2and the high-temperature disordered fee solid solution, a,3 within a small range of temperature in the vicinity of 1070°C. Structural studies included X-ray diffraction analysis* and electron-transmission microscopy examination* of stoichiometric composition speci- mens homogenized for 1 hr at 1200oC and either air-cooled or water-quenched. The air-cooled specimens yielded X-ray diffraction evidence of the k phase, while electron microscopy revealed a microstructure of both heavily and moderately faulted regions as shown in Fig. 1. The high density of stacking faults (or fine twins) in region A is reminiscent of hexagonal cobalt following its allotropic transformation.4 Selected-area diffraction from this region revealed distinct superlattice reflections of the ordered hexagonal phase, as well as continuous rel-streaks which were normal to the fault planes in the micrograph. The latter is indicative of extremely small spacings between the faults.' Regions such as ß were found to be only partially transformed to the k phase. Attempts to study the antiphase domain structure by either bright- or dark-field techniques were unsuccessful in these initial studies. This was due to the low intensity of the superlattice reflections arising from the closeness of the cobalt and vanadium scattering factors. Quenching Co3V from above Tc appears to suppress the formation of the k phase. Both X-ray and electron-diffraction results indicated that the disordered phase, a, was partially ordered during severe cooling and that the structure of the ordered phase was of the L12 (Cu3Au) type,6 designated here as a'. As in the case of the hexagonal phase, examination of the domain structure was unsuccessful; however, significant information concerning the morphology of this condition was revealed by the appearance of dislocation arrays. In particular, it

Jan 1, 1965

By W. M. Rust, W. D. Mounce

The almost universal acceptance of electrical logging by the petroleum industry calls for a critical examination of the physical bases of the common methods. This is particularly needed for the natural potential log. The conventional explanations are based on the phenomena of electrofiltration and electro-osmosis. However, experimental data show that they fail to give a basis that is quantitatively sound. Moreover, they lead to interpretations of details of electrical logs that are erroneous. It was found experimenlally that when a plug of shale is placed in a chain of dissimilar electrolytes, a current flow results. Experiments on oil-well cores and fluids similar to those existing in wells show that potentials are set up which are in reasonable agreement with those encountered in electrical logging. Doubtless other sources of potential are important but this explanation not only accounts for much of the potential but also clarifies some fairly familiar examples of misinterpretations. Introduction The extraordinary value of electrical well logging as a tool for petroleum engineers and geologists is now so universally recognized that it is not necessary to point out the ways in which it can be useful. It is sufficient to mention only the saving that has resulted from the elimination of much coring that would have been necessary under former practices and the considerable additions to reserves resulting from the discovery of sands missed in coring. Paradoxically, the very remarkable success that has resulted from the application of electrical logging to correlation and completion problems has cost some of its most consistent users dearly.' The fact that some operators have placed unwarranted faith in erroneous interpretatioils of electrical logs does not reduce the value of the logs. It should, however, make one pause long enough to ask why experienced users should be misled. The answer to this question is not hard to find. In nearly every case, the fault has been oversimplification. This is illustrated very aptly by the familiar interpretation and theory of the natural potential log. Recording and Interpreting Logs The natural potential log is extremely simple to record precisely enough for all present-day uses. One needs only an electrode, a cable to lower the electrode through the drilling mud, a recording meter and a surface ground connection. The electrode can be elaborate but need not be. A simple brass rod 2 in. in diameter and 2 or 3 in. long is quite satisfactory. The cable need not be particularly well insulated, nor need it have a very low resist-

Jan 1, 1946

By Ralph J. Schilthuis, William Hurst

The nature of the forces that are important in producing the oil in the East Texas field and the manner in which these forces are affected by the rate of production have always been problems of outstanding interest. These questions are of great interest to the industry as a whole on account of the economic importance of the East Texas field and to the engineers in particular on account of the unique character and behavior of the field. Subsurface pressure data throughout the field have been collected systematically, so that a quite complete history of the reservoir pressures has been kept as the field has been developed and produced. Subsurface samples of the oil and gas have been taken and these have been examined to obtain data on the physical properties of the reservoir fluids under the actual conditions of temperature and pressure. All of these data have been valuable because they have afforded the basis for a careful study of the means by which the oil is produced. It is the purpose of this discussion first to point out several of the important facts revealed by the data mentioned and then to describe studies that have been made concerning the interpretation of these facts. Reservoir Pressure Data and Properties of Oil The reservoir pressure data on the East Texas field have shown conclusively that the pressures are readily affected by changes in the rate at which the field is produced. This can well be seen in Fig. 1, where the average reservoir pressures obtained from time to time are plotted with the daily production rates and the cumulative production of the field. It is noted that the average reservoir pressure has declined irregularly, depending upon the rate of production, from the estimated original value of 1625 Ib. per sq. in. to the value of 1228 lb. per sq. in. observed for Aug. 11,1934. The decline in pressure has been more rapid at the higher rates of production than at the lower rates. In contrast, the average reservoir pressure has increased, on several occasions, upon reduction of the withdrawal rate from a high value to a lower value. The reservoir pressure data have also shown that a definite gradient in pressure has existed across the field from west to east since the begin-

Jan 1, 1935

By N. E. Holden, R. R. Goodrich

TheRe is a small area about Murray where bedded gold quartz veins occur in Prichard slate. The ore taken from the upper levels, during the early days, was free milling and was treated by stamp milling and amalgamation. There was likewise a considerable placer working. The report is current that tungsten (scheelite) was encountered, which interfered with the amalgamation in the stamp mills and which, in placering, collected in the riffles in the sluice boxes and clogged them. Consequently, in the quartz mines, the scheelite, when encountered, was rejected, being thrown into the waste, sometimes inside the mine and at other times outside on the dump. The free surface ores became worked out and as the ore in depth became pyritic and rebellious to amalgamation the mines closed down. Last spring tungsten ore brought a high price, near $80 per unit, 60 per cent. W03 and up. This so stimulated the output of tungsten ore that old dumps were explored and waste stored in the mines was gone over. Tungsten was likewise mined from virgin ground. So the district produced quite heavily for a time. The condition now is different. The price is not so high, about $20 per unit WO3, which makes profits questionable when mining in new ground. The accumulations from early day mining have been exhausted and the output has greatly declined. The Golden Chest mine was the heaviest producer of tungsten. The months of June and July were spent at this mine studying the problem. Since the mine had produced both gold and tungsten, we looked forward to the problem of recovering both from what might be called a gold-tungsten ore. A study of the Golden Chest vein showed this was not to be the case. While gold ore and tungsten ore come from the same vein, the tungsten ore is confined to a more or less disturbed or distorted portion

Jan 1, 1918

By P. A. Boeck

The thermal insulation of high-temperature equipment for industrial purposes is a subject that has not received from engineers and designers the attention its importance deserves. This may be attributed to a number of causes: In the first place, heat flow is a rather difficult factor to measure under the working conditions of an industrial furnace, and until the comparatively recent introduction into certain operations of the heat balance sheet, with a systematic attempt to account for the discrepancies in the totals, the various causes of heat losses and the reasons for their existence were not brought to light. Moreover, such rapid advancement and radical changes in the design of equipment, especially in metallurgical lines, have occurred that practice has apparently outdistanced the theory of design. In the modern tendency toward greatly increased size of units, effort has seemingly been made to utilize the heat of fuel gases without proper attention having been paid to conserving heat energy and confining it strictly to the points of maximum activity. The systematic study of the thermal properties of structural materials, which is being carried out by various government bureaus and also by a number of technical societies, is forming the basis for more intelligent and consistent work in the economically important subject of prevention of fuel waste. Advantages of Insulation It is not necessary in this practical and utilitarian age to enlarge upon the need of prevention of heat losses, but attention may advantageously be called to the other benefits derived simultaneously with the saving in fuel and the increase in thermal capacity of furnaces when properly insulated. In most industrial furnaces—which are here spoken of in the broadest sense, indicating general high-temperature equipment for any purpose and heated in any manner—the operations are generally carried on through a temperature range which has been found by practice to give the most ef-

Jan 1, 1916

Now producing 35,000 tpd of coal from a deposit whose estimated reserves total 1.1 billion t, the Navajo mine of Utah International Inc. near Farmington, N. M., is the largest open-pit coal operation in the US. The history of this mine began in 1953 when, foreseeing the growing need for electrical power in the southwest, Utah International obtained a prospecting permit from the Navajo tribe. The lease, now covering 31,000 acres of the 12-million acre New Mexico-Utah-Arizona Navajo Indian reservation, was entered in 1957; in the next 3 years, Utah International negotiated with the State of New Mexico for water rights on the San Juan River, and finalized an agreement with the Arizona Public Service Co. to provide coal for the proposed Four Corners power-generating plant near Farmington.

Jan 10, 1974

By Rudolph Emmel

The mines operated by the South American Development Co. are located in the Zaruma mining district of southwestern Ecuador. They are near the old mining town of Zaruma, which is the only important city in the canton of the same name. The district is situated in the upper end of a valley lying between two spurs of the Cordillera, one of which may be considered the Coast Range and the other an intermediate range. The mining camp proper, known as Portovelo, and the plant are 2.4 km. south of Zaruma, on the north bank of the Amarillo River, a tributary of the Tumbes River, which flows southwestward through Peru to the Pacific. Portovelo is difficult of access; it is reached from Guayaquil by means of river steamers and muleback. 'Embarking at Guayaquil, the route is down the Guayas River, across the Jambeli Canal, and up the Santa Rosa River to Santa Rosa, a distance of 177 km. From Santa Rosa, the road or trail follows the Santa Rosa River, then across the summit of the Coast Range into Portovelo, a distance of 74 km.—a two-day trip on muleback. The mining property of the South American Development Co. comprises 297 lode claims and 142 placer claims. The combined lode claims cover an area, roughly rectangular in shape, 9000 m. long from north to south by 4000 m. wide; the northern edge of the rectangle is about 3000 m. north of the central plaza of Zaruma. Mineral lands in Ecuador are held by virtue of an annual tax per claim paid to the central government, no surface rights being included. HiSTOry The Zaruma mine has been worked by white men since 1549, probably before that it was worked by Indians. The followers of Pizarro, led by traces of gold in the sands of the Tumbes River, followed that stream to its source, worked the gold veins that they found and established the city of Zaruma. Among the mines worked by them were th Sesmo, Leonora, Viscaya, and Mina Grande. Only the soft ores at the outcrop were

Jan 1, 1925

By G. D. Arsdale

This paper describes a series of experiments leading to the development. of a method for leaching the mixed ores of the Inspiration Consolidated Copper Co., containing chalcocite and silicates of copper, by the use of solutions acidified with sulfuric acid and carrying ferric sulfate. Iron is added to the solutions and ferric iron is regenerated electrolytically to a percentage high enough to act as an efficient solvent. The decreased yield is partly compensated for by a higher current density. AN IMPORTANT problem in modern copper metallurgy, particularly in the Southwest, has been to obtain good recoveries from what are commonly known as mixed ores; that is ores in which the copper occurs partly as oxide and partly as sulfide compounds. The dividing line between mixed ores and ores commonly accepted as concentrating is not definite. In other words, much ore now being concentrated carries considerable copper in non-sulfide form, on which recoveries are hot so good as on ores carrying less of these constituents. While treatment by concentration may be commercially profitable, on ores carrying oxide copper within certain limits, there are large deposits for which the application of con-centration could not be considered, and yet which have not been considered amenable to leaching because they carried too much sulfide. The Inspiration Consolidated Copper Co. has large amounts of such mixed ores, and this paper is an account of the experimental work by which a method was developed for their treatment, and for which a large plant is now being erected by the Inspiration Co. It is not claimed that the method is a general solution of the problem of mixed-ore treatment but it is apparently well adapted for leaching the ores of the Inspiration Co., for which it was designed. The work done has covered preliminary laboratory and test-plant investigation, and .a pilot-plant run, extending from March to the middle of December, 1923. Thoroughly consistent and satisfactory results, were obtained continuously for more, than six months in the pilot plant; and it is believed that the results; and probable costs that can be had on a large scale have been definitely, proved. The method, however, was designed for local conditions; and while the basic principles are general, there are ores on which it will not work and other ores for which considerable modification may be required.

Jan 10, 1925

By Edna A. Dancy, Ronald L. Pastorek, Gerhard J. Derge

In an earlier study1 in this laboratory, it was found that there is a minimum in the specific conductance of Ni-S melts in the region of the stoichiometric composition, Ni3S2. This and similar observations on other sulfide1 and telluride2 systems suggest that short-range order exists in the molten phase for several hundred degrees above the melting point, and a qualitative energy-band model has been proposed, with intrinsic semiconduction at the stoichiometric composition and degenerate electron and hole conduction at metal- and tellurium-rich compositions. This suggestion has been substantiated for the telluride systems by Seebeck coefficient measurements which showed a change in sign from negative on the metal-rich side to positive on the tellurium-rich side. In the present investigation, in order to substantiate still further the proposed model, Seebeck coefficient determinations have been extended to the Ni-S system over a composition range in the vicinity of Ni3S2. The experimental method was essentially the same as that used for the telluride systems, with minor modifications on cells for high sulfur melts to permit the use of tungsten wires and W— W-Re th~rmocouples instead of the chrome1 or alumel wires and chromel-alumel thermocouples originally used. Chrome1 and alumel both deteriorate very rapidly in atmospheres containing sulfur. The Ni-S alloys were prepared as described in the conductivity paper. Initially, a portion of the solidified melt was analyzed at the end of a run, but after this was found to be inaccurate because of segregation during cooling, the whole sample was analyzed. The nickel content, only, was determined, the sulfur content being obtained by difference. The results are summarized graphically in Fig. 1, and clearly show a change in the sign of the Seebeck coefficient in the region of the stoichiometric composition. This change of sign near Ni3S2, coupled with the minimum in the conductivity, is suggestive of an intrinsic semiconductor at the stoichiometric composition, with degenerate electron and hole conduction on either side of this composition, in keeping with the proposed model. The negative temperature coefficient of conductivity, normally indicative of metallic conduction, is not inconsistent with this model. In the completely degenerate region it would be expected, while in the vicinity of Ni3S2 the suggestion originally made by Argyriades, Derge, and pound3 for the Fe-S system can probably be applied. They proposed that the forbidden gap between the valence band and the conduction band is small, and that the increase in the number of the conducting species with increase in temperature is not large enough to compensate for the loss of mobility through thermal scattering. The research was sponsored by the Office of Naval Research under Contract NONR-760(22) Project NR 039-081. 'E. A. Dancy and G. J. Derge: Trans. Met. Soc. Aime, 1963, vol. 227, pp. 1034-38. 'E. A. Dancy: Trans. Vet. soc. AIME. 1964, vol. 233, pp. 270-77. 'D. Argyriades, G. Derge, and G. M. Pound: Trans. Met. Soc. . 1959, vol. 215, pp. 909-12.

Jan 1, 1965

By AIME AIME

COUNCIL PRESIDENT OF THE COUNCIL. CHARLES KIRCHHOFF NEW YORK, N. Y. (Term expires February, 1912.) VICE-PRESIDENTS OF THE COUNCIL. BENJAMIN B. LAWRENCE NEW YORK, N. Y. JOSEPH W. RICHARDS SOUTH BETHLEHEM, PA. ALBERT SAUVEUR CAMBRIDGE, MASS. (Term expires February, 1912.) S. B. CHRISTY BERKELEY, CAL. W. A. LATHROP PHILADELPHIA, PA. GARDNER F. WILLIAMS WASHINGTON, D. C. (Term expires February, 1913.)

Oct 1, 1911

By A. H. Daane, J. F. Haefling

BECAUSE of the wide use of platinum in industry and research, the physical properties of this metal, including its vapor pressure, have been studied in some detail.' The other members of the palladium-platinum group of metals have not been studied as extensively, and only qualitative information is available on the vapor pressure of palladium. Data given in literature by Vines1 and Brewer2 on the vapor pressure of palladium are based on the qualitative observations by Holborn and Austin3 and Crookes4 on the rate of volatilization of palladium filaments in various atmospheres. The general observation that palladium is the most volatile metal of the palladium-platinum metal group was corroborated by Bell, Love and Normand who studied the separation of isotopes of the platinum-group metals by a mass spectrometric method. We have measured the vapor pressure of palladium using the Knudsen effusion technique. In this work, the effusion vessel was suspended from a quartz-fiber microbalance into an induction furnace, and the amount of vapor effusing from the vessel was determined by direct weighing of the vessel during the measured heating times. This technique has been described in a report from this laboratory." The vapor pressure of palladium was calculated from these measurements using the equation P...... = 17.14 -W- (77m)'u [1] a t where ? is the weight loss in grams of vapor of molecular weight m from a vessel having an orifice of a sq cm, during t sec. The derivation of this equation from kinetic theory has been described in a previous report from this laboratory: as well as in texts discussing the kinetic theory of gases.%" Test Vessel—In the search for a suitable material for the effusion vessel, it was found that tantalum reacted with palladium metal to form intermetallic compounds, and graphite was readily dissolved in palladium metal to form what appeared to be a liquid phase at a temperature several hundred degrees below the melting point of palladium. On cooling, the graphite gathered into spherical balls in the palladium, with crystals extending radially from the center of these balls, some of which were a millimeter or more in diameter. However, palladium metal vapor did not attack the graphite vessel, so graphite could be used where it did not contact condensed palladium. Tungsten did not appear to react with palladium vapor or molten palladium at its melting point, but it was not convenient to use a tungsten-vapor pressure vessel because of the difficulty of fabricating this metal. Since the vapor-pressure range to be studied (10 2 to 10 ' mm) did not appear to extend above the melting point of palladium, a combination of tungsten and graphite served to provide a very satisfactory effusion vessel. The lower half of the graphite vessel was lined with some strips of tungsten foil and the sample of palladium consisting of a coil of sheet was placed in the tungsten liner; in this way, no contamination of the palladium by carbon occurred. Procedure After outgassing at 1500C, the tungsten-lined graphite effusion vessel was loaded with 300 mg of

Jan 1, 1959

HOW the Engineers' Memorial clock and carillon at Louvain has impressed the people of that city is indicated by the following letter sent by the Secretary of the University of Louvain to the Secretary of the United Engineering Society. We are still full of the memories of that splendid July 4, when we came into such .delightful contact with our American friends and more specially with the representation of the engineering societies of the United States. It was a great joy for all the members of the University to see those, American friends who have given to us such a splendid memorial in honor of- the brave men who fell in the Great War.

Jan 1, 1928

By J. E. Tobey

UNDER war conditions coal immediately assumes a position of highest importance for coal must carry the basic load for industry. The upward trend in production continued through 1941. Bituminous coal production alone about equaled the total output of bituminous and anthracite in 1940. The figures for 1941 approximated 500,000,000 tons for bituminous, and 54,000,000 tons for anthracite, and production of by-product and beehive coke exceeded that of the previous year. The coal industry, under the National Bituminous Coal Act, is going through a period of readjustment, and is beginning to stabilize itself under the statute. The Federal Mine Inspection Nill became law during the year.

Jan 1, 1942

By W. Mckewan, W. M. Fassell

The oxidation rates of copper have been determined at temperatures from 600" to 900°C in oxygen from 14.7 to 400 psi total oxygen pressure. The oxidation rate of copper is unchanged by oxygen pressures within the range studied. The observed data extend Feit-knecht's conclusion concerning the pressure independence of copper from atmospheric pressure to 400 psi. All samples studied in the above-mentioned temperature and pressure range have both Cu2O and CuO present in the oxide film. NUMEROUS papers have been published on the oxidation of copper, some of which have noted the effect of oxygen pressure on the oxidation rate of copper. It must be noted, however, that no data on the oxidation rates of copper at pressure in excess of 1 atm have been reported in the literature. (Le Chatelier¹ reported that a black oxide of silver was formed at 300°C and 15 atm pressure.) This is likewise true for the other metals. This investigation was initiated to obtain experimental oxidation rate constants for pure metals at elevated temperatures and high oxygen pressure. Copper was selected as the first metal since probably more reliable data are available on its oxidation rates and related physical and chemical properties than for any other metal or alloy. As a general summary, the following conclusions appear well established for the oxidation of copper: 1—The oxide coating consists of Cu2O with a superficial coating of CuO providing the ambient oxygen pressure exceeds the equilibrium pressure for the coexistence of Cu2O and CuO.² The following sequence of phases is then Cu/Cu2O/CuO/O2 (gas). The Cu2O consists of large crystals that have no relation to the orientation of the metal crystals, except for a very thin layer adjacent to the metal." The CuO consists of very fine crystals randomly oriented. If the oxygen pressure is below the equilibrium pressure for the coexistence of Cu2O and CuO, the coating consists of Cu,O only. 2—The rate-determining factor in the parabolic oxidation of copper is the diffusion of Cu+ ions through the Cu,O layer.4,6,7 The Cu+ ions are accompanied by electrons to maintain electrical neutrality. The mechanism of the reaction at the Cu2O/CuO interface and the method of growth of the CuO is in some doubt. 3—On copper, there are three reported pressure effects: (a) At pressures below 0.3 mm Hg oxygen pressure, the oxidation rate increases directly with pressure.', ' .Vxygen starvation at the surface may account for this effect. (b) At oxygen pressures from 0.3 to 63 mm, the oxidation rate increases as the 7th root of the oxygen pressure providing the temperature is such that only Cu2O is present in the film. (c) At pressures from above the equilibrium pressure for the coexistence of Cu2O and CuO (varies with temperature) to atmospheric pressure, the oxidation rate is independent of the oxygen pressure.' Equipment In order to determine the oxidation rates of metals in an oxidizing atmosphere at pressures up to 400 psi, the equipment is somewhat different than for low pressure work as is shown in Figs. 1 and 2. A Leeds and Northrup Micromax recording controller (A) is used to control the temperature of the Ni-chrome furnace winding in conjunction with a Micromax electric drive unit. The drive unit adjusts a 20 amp Variac (variable transformer) to control the power input into the Nichrome furnace winding. Due to the "self heating" of the sample by oxidation, frequently encountered in oxidation rate studies, it is essential that the sample temperature be measured independently. This is done by means of a series of six chromel-alumel calibrated thermocouples located spirally around the oxidizing metal sample. Each thermocouple is partially shielded from the direct radiation of the furnace wall by

Jan 1, 1954

By J. R. Low, D. F. Stein

Single crystals of iron have been grown from three different lots of Ferrovac "E" of somewhat different chemical composition by the strain anneal technique. Using a technique to seed the crystal similar to Dunn's for silicon-iron, it has been possible to orient the crystals grown in both direction and plane of growth. Crystals having the plane of the strip oriented (100) , (110), (111), (112), (123), and (491) have been grown. The growth directions used have been [100], [110], 45 deg from a [110}, and various others of no specific crystal orientation. The usual dimensions of the crystals were 8 by 1 by 0.08 in. Attempts to grow crystals were about 90 pct successful. METHODS of growing single crystals of high purity iron have been reported in the literature.1-4 However, each of these methods was not completely reliable when used on materials having slightly different chemical composition and in some instances a small number of successes were obtained using identical materials. Except for the method used by S. Dohi and T. Yamoshita,1 it has not been possible to reorient single crystals of high purity iron to give any desired orientation. The method to be described has made it possible to grow single crystals from three different lots of material having different compositions, and to orient the crystals with respect to growth direction and surface. STARTING MATERIAL The material used during this investigation was a vacuum melted high purity iron marketed by the Vacuum Metals Corporation designated Ferrovac "E." Three lots of Ferrovac "E" having the following composition were used with equal success: The compositions listed are those of the as-received material; and they may have been modified before the growth of single crystals. Analysis of heat B just before growth and after growth revealed that the heat treatment prior to growth did not change the carbon content, but the oxygen content was changed from 0.0092 pct to 0.0034 pct and the nitrogen content from 0.0003 pct to 0.0001 pct. After growth of the single crystals, the carbon had dropped to 0.001 pct. None of the heat treatments would be expected to change any of the other impurities very markedly. Heat C would be expected to have a metallic impurity content similar to heats A and B. PROCEDURE Ferrovac "E" iron which had been obtained in bar form having a diameter of about 1 in. was rolled into strip for growing single crystals. By passing the 1-in. bar through a cold rolling mill several times, it was reduced to a strip 0.15 in. thick. The strips obtained were then cut into suitable lengths for heat treating (about 9 in. long), annealed at 925°C for 2 hr in dry hydrogen and water quenched. It was then necessary to bake the strip at 200°C for 24 hr in air in order to prevent cracking during further rolling operations. While it was possible to cold roll the 1-in. bar directly to the desired 0.080-in. strip, the intermediate anneal was used because the strip so obtained produced better single crystals. The strip obtained by rolling the 1 -in. bar directly to 0.080-in. strip produced single crystals having a large number of occluded grains. Experiments showed that the optimum reduction in area by rolling prior to the growth of single crystals was about 50 pct. Attempts to grow single crystals from material that had been reduced less than 40 pct were unsuccessful presumably because the matrix did not possess the critical amount of texture necessary for growth. The strip obtained after the rolling operations had very irregular edges which were ground to give a strip with uniform dimensions. The strip was then annealed at 825°C for 3 hr in hydrogen and furnace cooled. Fig. 1 illustrates the grain size obtained. A temperature of 940°C was used for the annealing temperature on one group of strips

Jan 1, 1962

By AIME

WELL known as an outstanding practical metallurgist, the Chairman of the Institute of Metals Division also possesses a rare combination of research and administrative abilities. Louis W. Kempf was born in Muskegon, Mich., on March 22, 1898. Following his graduation from high school, he obtained considerable experience in the automobile industry while employed by Continental Motors, the Studebaker Corp., and Dodge Brothers. He enlisted in the U. S. Army Signal Corps in 1917, and served overseas with an aviation unit. In 1919, Mr. Kempf entered the University of Michigan and earned both B.S. and M.S. degrees. While there he was elected to Tau Beta Pi, Phi Lambda Upsilon, Alpha Chi Sigma, and Gamma Alpha. In 1924, the Aluminum Co. of America secured his services as a research metallurgist. With a steady job he married Elizabeth Skelley in Cleveland in 1926. They have one son now seventeen. After six years Mr. Kempf was made manager of the Cleveland research division of the Aluminum Research Laboratories which position he held until last year. In 1945 he was promoted to assistant director of the Laboratories. He will direct research involving process metallurgy in Cleveland and New Kensington.

Jan 1, 1946

By H. L. Tedrow

FACED with a scarcity of labor in its operations at Alma, Colo., the London Mines and Milling Co. has been employing women for several months in its sorting and crushing plant. The results so far obtained indicate that women can be used successfully and to good advantage on a number of various jobs around the surface plant of an ordinary mine. Eight women are now employed as sorters to pick waste out of the ore as it passes by them on a sorting belt. After a short period of breaking in they have become adept at their work and are doing better work than that formerly done by the class of labor obtainable. They are continually warned and instructed, particularly from the standpoint of safety and their physical strength.

Jan 1, 1942

By AIME AIME

FRIEND recently remarked that the career of Scott Turner is characterized by Work and Wild -A Ducks. To these might be added Accomplishment and Persistent Fishing. All of these elements are manifestations of his character. The diversions-hunting and fishing-are in the nature of the proverbial trolley conductor's holiday, for many of Turner's years have been spent in the outdoors, often in distant lands, as in Spitzbergen, where the ducks pictured below were bagged. The election of Scott Turner to the presidency of the Institute marks the culmination of a quarter century of membership, during the last two years of which he has been vice-president. He was born at Lansing, Mich., on July 31, 1880, and received his A.B. at the University of Michigan in 1902, with a B.S. and E.M. at the Michigan College of Mines in 1904. Since then he has been granted two honorary degrees, D.Sc. from the Colorado School of Mines, and D.Eng. from the University of Michigan, but he still prefers to be called "Scott" rather than "Doctor." Government service was not a new experience for Turner when he was appointed Director of the U. S. Bureau of Mines by Secretary Hoover in 1925, for his first employment after graduation was as Field Assistant in the U. S. Geological Survey in Oregon and Idaho. This was followed by work in Tombstone, Ariz.; then his first foreign engagement in 1905-6 as superintendent of the San Pablo Gold Mining Co. in Panama. Various field experiences followed, though there was an interlude in work of a kind that few mining engineers ever experience. This was in technical journalism, for in 1906 he was

Jan 1, 1932

By Lo-Ching Chang, J. Chipman

The perennial and increasing interest in the chemical behavior of steelmaking slags has led to numerous attempts to formulate the thermodynamic properties of these solutions. The classical view is that of a solution of the component oxides in which certain acidic oxides are more or less completely held in combination with basic or metallic oxides, the nature of the interoxide compounds being derivable from the chemical behavior of the slag or from the mineralogy of a solidified specimen. The known electrical conductivity of slags has pointed to the existence of ions in the solution and a number of attempts have been made to account for the observed facts of slag behavior on the basis of a theory of complete ionization of the solution. It is the purpose of this paper to examine, in the light of ionic theory, a number of recently published series of data on slag-metal and slag-gas equilibria, with the purpose of obtaining a more complete or more satisfactory generalization than has been possible on either of the single bases of simple compound formation or complete ionization. The attempt to formulate the ionic constitution of a complex solution is fraught with many uncertainties. An ion is not something that can be plucked from the solution and examined in detail, nor can its true formula be determined with certainty by any single experimental method. In attempting to express the composition of a slag by various ionic formulas it can be expected that alternative hypotheses of essentially equal merit will present themselves. In the present state of early development of the ionic theory of slags, it may be necessary to make some rather arbitrary choices of ionic formulas in the absence of su- cient information to yield complete certainty. Acids and Bases The classification of slag-forming oxides as acidic or basic apparently dates back into the days of Berzelius. It is difficult to see how the concept could have originated in the early twentieth century when it was fashionable to define an acid or a base as an aqueous solution containing hydrogen or hy-droxyl ions. It is, however, entirely consistent with the modern and more general theory of acids and bases. In this theory, as originally formulated by G. N. Lewis,' a basic molecule is one that has an electron pair which may enter the valence shell of another atom thus binding the two together by the electron-pair bond. An acid molecule is one which is capable of receiving such an electron pair into the shell of one of its atoms. The acid, the base, and the product of neutralization may be either ions or neutral molecules. The product of such a reaction may itself be a base or an acid if it is further capable of giving or accepting an electron pair. Thus a base is a donor of electrons, an acid, an acceptor. In oxide slags the typical and ever-present base is oxide ion, 0-—. In behavior and in importance it is analogous to hydroxyl ion, OH-, which is the typical base of aqueous solutions. There is nothing in the chemistry of slags which is quite analogous to the acid H30+ in aqueous solutions. This is not surprising for in slag systems there is nothing which can be designated as a solvent and no ubiquitous positive ion. The chemistry of slags is in fact more complex than the chemistry of aqueous solutions and the concepts which must be evoked in its study are correspondingly broader. In seeking a basis for a classification of slag-forming oxides as basic or acidic it must be remembered that these terms are not absolute but relative. A substance which acts as a base toward a second substance may act as an acid toward a third. This is less likely to happen among strong bases or acids than among the weak ones; there are numerous examples of weak acids which under the influence of a stronger acid behave as weak bases. Such substances are called amphoteric. A classification of the glass-forming oxides has been proposed by Sun and Silverman² and further developed by Sun3 in which the oxides are arranged in order of decreasing acidity or increasing basicity, each substance being potentially capable of acting as an acid toward substances below it in the list and as a base toward those above it. It is based upon the relative strengths of the metal-to-oxygen bond as determined by the energy required to dissociate the oxide into its component atoms.' Data are available for computation of this energy, at least approximately, for the oxides of slags and glasses. In general those oxides from which it is most difficult to remove the positive atom are the strong acids while those in which it is most loosely held are the strong bases. It is in the latter, of course, that formation of oxide ion occurs most readily as, for example, in CaO which in solution ionizes to form the weak acid Ca++ and the strong base O—. The order of arrangement found by Sun is shown in the first column of Table 1, to which have been added the data for

Jan 1, 1950

By AIME AIME

DESPITE the meetings and discussions on over- production the situation still continues to grow worse instead of better. The demand for oil has dropped to 2,700,000 bbl. per day. On the other hand domestic production has risen to 2,700,000 bbl. with prospects of further increases, and if imports and natural gas-gasoline be added to this the current supply is about 3,100,000 bbl. per day. Though during the summer and early fall the demand may exceed this figure for a few months the prospects are that 'the average demand during 1929 will be at least 200,000 bbl. per day less than the present current supply, meaning additions to stocks over the year of about 75,000,000 bbl.

Jan 1, 1929