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By J. K. Abraham

In recent years there has been interest displayed in the precipitation phenomena occurring in austenitic alloys based on the binary Fe-Ni system.1'2 Previous communications have been extended covering the kinetics of clustering in the Fe-Ni-Ti system and the effect of cluster size on subsequent mechanical properties.3'4 To a great extent the question of coherency, which has a dominant role in determining the mechanical properties, is dictated by the degree of misfit between the precipitate and matrix. Thus, the change in lattice parameter of the matrix with composition is an important variable that should be examined. The lattice parameter, ao, of austenite was determined for Fe-29.75 Ni-1 to 6 Ti and Fe-27 Ni-1 to 10 Ti alloys in this study. The alloys used in this investigation were melted in a vacuum induction furnace from a starting stock of plast iron (99.95), electrolytic nickel (99.9), and ti- tanium sheet (99.5) in a MgO crucible. The alloy compositions in atomic percent are given in Table I and their relative position in the Fe-Ni-Ti ternary is indicated in Fig. 1. The chemical analyses were taken from the homogenized bulk materials treated in a manner related earlier.3 A diamond file was used to obtain powder from the bulk. To remove the stresses induced by filing, the powders were austenitized at 1875°F for

Jan 1, 1969

By Joseph Richards

PLATING iron with copper has received great attention from practical sand scientific men, but, aside from the deposit secured by immersion of iron in copper salts, by electro-plating, or by welding together thin sheets of iron and copper, these efforts have met with no success. Failure of these efforts, in the production of copper plating, has been due to the fact that the conditions normally and necessarily present in the plating operation are antagonistic to the production of copper-plated iron. In most, if not quite all of them, a bath of molten copper has been used. The-temperature of a molten copper bath is so high that the iron becomes oxidized before it can be immersed in the molten copper, and unless protective flux for the molten copper is used, the surface of the copper will become oxidized, and, in any event, the plated iron will oxidize immediately on its being withdrawn from the molten bath. I recently had the pleasure of visiting the works of The Metals Plating Co. at Elizabeth, N. J., where I witnessed the plating of iron sheets with copper by a new process.1 The plating metal is applied to the sheet in the form of a liquid mixture by means of rolls, such as inking rolls. The sheet, after being coated with the mixture, is automatically carried forward and deposited on a link-belt conveyor, which carries it through a furnace maintained at a. temperature well above that of molten copper. The basic principle involved in this method lies in the application of the plating metal to the sheet while the sheet is cold and then melting the metal in place on the sheet under conditions which are favorable to the formation of the plating.

Jan 1, 1919

By Fulton B. Flick

The micrography and macrography of aluminum and its alloys present certain difficulties. Many of the difficulties attendant on the micrography have been removed by methods developed during the past few years, notably those of E. H. Dix, Jr.1 The development of grain size in aluminum and its alloys may be equally troublesome, yet comparatively little detailed attention appears to have been given to it. Satisfactory reagents are available for the development of such structurcs in ferrous and most non-ferrous metals, but those applied to aluminum and its alloys, i. e., alcoholic or aqueous solutions of sodium hydroxide or hydrofluoric acid are not entirely satisfactory. Hanson and Arch-butt,2 in speaking of these two reagents, state that "These two reagents give fairly satisfactory results, but they sometimes produce badly tarnished surfaces from which the surface deposit is difficult to remove." It has been our experience that neither of these reagents is to be entirely relied on for developing structures suitable for study or photography. This means that when the etch fails to produce satisfactory results the specimen must be repolished, through the 000-paper at least, and then etched with another reagent. This procedure entails a considerable loss of time, and the final results may not be all that might be desired. However, the reagent to be described, although not a panacea for all etching troubles, has improved results so markedly that it is felt that it & worth offering as a grain-size etch generally applicable to aluminum and aluminum alloys. Czochralski3 in 1915 mentioned the application of a solution of 10 to 20 c. c. concentrated hydrofluoric acid in 100 c. c. absolute alcohol, etching in this reagent being followed by dipping in concentrated hydrochloric acid soliltion.

Jan 1, 1925

By C. M. Weld

In the course of my professional work in China during the fall of 1907, I had an opportunity to visit the iron-ore mines at Ta-yeh in Hu-pei province (long. 114O 50t E., lat. 30' 20t N.). It occurs to me that a rescript and discussion of my notes taken at that time should be of interest, particularly as supplementing the exceedingly interesting recent paper of Thomas T. Read on The Mineral Production and Resources of China.' Ta-yeh is situated near the right bank of the Yangtze river. The mines are at an average distance of about 16 miles from the river-port Shi-hui-yao, which in turn is some 70 miles SE. of Hankom. The ores are shipped to the works of the Han-Yeh-P'ing Iron & Coal Co. at Hanyang, as also very largely to the Japanese government iron- and steel-works at Wakamatsu, Japan. Smaller qnantities have been exported to the Pacific coast of the United States. These ore-deposits have been briefly noticed in a number of publications, but, so far as I know, Mr. Read's description, in his chapter or1 the iron-ores of the Chinese Empire,2 contains the first attempt to define their geological character. In his more recent paper Mr. Read follows very closely the text of his earlier description. To quote briefly from the recent paper, he says : " The iron-ores at Ta-yeh .... lie along the contact between a marble and an intrusive body of a dark-gray syenitic rock." He refers to a figure which exhibits in plan, but not in section, the relative positions of the syenite, ore-bodies, and limestone. The contact is seen to trend approximately E-W., with the syenite on the north and the limestone on the south. " The syenite lies to the north of the marble, and a few miles farther north the marble again appears, iron-ore again being present along the contact." No litho-

Jan 1, 1913

By A. Eilers

NO one who has visited our Western mining districts, and studied the economical part of the beneficiation of the ores occurring all over that vast extent of country, can underrate the high importance of the above subject. By far the larger number of the districts which contain smelting ores, i. e., argentiferous and auriferous lead, or copper ores, are situated in the Great Basin, that great plateau between the Rocky Mountains on the east, and the Sierra Nevada on the west, almost the whole of which is comprised at present in the boundaries of Nevada, Utah, and part of Arizona. This region is essentially a barren country. The extreme dryness of the atmosphere permits but a scanty vegetation in the plains; and even in the detached mountain-chains running through it-generally from N. to S., or from N. W. to S. E.-there are no trees found except dwarfed pines and mahogany, at the head of sheltered ravines, and a few cottonwoods and willows, which fringe the insignificant streams, before the water sinks in the arid plains. Nearly all the mountain-chains in this region are rich in silver ores. That class of these ores which is adapted to amalgamation, and rich in silver, has been worked with profit for more than ten years. But before the advent of the transcontinental railways, mining was restricted to these ores alone, and the consumption f fuel could be met with the scanty supply of forest trees in the immediate vicinity of the mining districts. Since, however, the Union and Central Pacific Railroads have brought the Great Basin nearer to the commercial centres of the East and the Pacific coast, thus reducing the expenses of freight and labor materially, other silver deposits, containing poorer ores in greater abundance, have been rapidly taken

By D. J. Weintritt, J. C. Cowan

Methods of studying oilfield mineral .scale deposition in the laboratory do not work for barium sulfate because only small nonadhering crystals ore formed. On the other hand, barium sulfate scale found in down-hole or surface equipment is strongly adhering and may contain very large crystals. Results suggest that most of the difference derives from the extremely low .solubility of barium sulfate. Firm adherence of scale and the consistent development of oriented crystals 100 microns and larger suggest a relationship between scale adherence and crysta1 growth. Data from this study indicate some reasons for barium sulfate's occurring as a deposit in oilfield waters. The unique characteristics as well as the associative properties of barium sulfate scale as related to calcium carbonate and calcium sulfate ere shown. INTRODUCTION The first observed deposition of barium sulfate scale in oilfield production equipment is unknown but probably coincides closely with the beginnings of the oil industry itself. Moore' described barite oolites in some producing wells in the Saratoga field, Tex., in 1914. Currently, positive identification of barium sulfate deposition is recorded in most of the major oil-producing areas of the United States. As efforts continue to identify the composition and functions of the materials found in scale deposits, the geographic and economic importance of the part played by barium sulfate will become even more important. This belief is based on the following Facts. 1. Many oil fields in the U.S. are in or entering their mature phase and the volume of produced water is increasing; thus, the cumulative effects of low-solubility minerals become more significant. 2. Secondary recovery techniques and increased emphasis on waste disposal systems require controlling the behavior of all constituents of water to prevent formation plugging. 3. The more general use of instrumental analysis has reduced the time and improved the accuracy of complete scale and water analysis. 4. Once formed, barium sulfate scale is resistant to present methods of chemical removal; therefore, costly mechanical methods are necessary. Thus, new methods of prevention and control will require specialized chemical techniques and better knowledge of the causes of scaling. Consider the results of some simulated field deposition studies illustrating this need (Fig. 1). The studies utilized a Scale Deposition Test Cell* and each coupon was exposed to 8,000 ml of a 300 me/liter solution of the various types of mineral scale. All tests were conducted at 140F. Only the calcium sulfate and calcium carbonate deposited scale. The solution containing 300 me/liter of barium sulfate exhibited copious amounts of precipitate, but none of the precipitate adhered. The fluids from the effluents were also allowed to impinge on glass slides. Fig. 1 shows the relative adherence of the three types of scale on unetched glass. The barium sulfate failed to deposit in the same manner as the calcium carbonate and calcium sulfate solutions.

By W. N. Best

(San Francisco Meeting, September, 1915) INTRODUCTION CRUDE oil attracted attention because of its excellence as a fuel for open-hearth furnaces; for making crucible steel and brass; for melting copper, lead, tin, zinc, nickel, silver, malleable iron, gray iron; and for the production of steam in all sizes and types of boilers. For heating furnaces, mold-drying ovens, core ovens, ore roasters, calciners, hot-air furnaces, sand drying, asphalt road work, etc., its superiority over other fuels is due to the fact that the heat is at all times under perfect control, so that a constant temperature may be attained and maintained at the will of the operator. This means a maximum amount and uniform quality of work. Crude oil is of two kinds, paraffine base and asphaltum base, and varies from 11 to 46 gravity Baumé. The light-gravity oil does not require heating before use; but oil of less than 20 gravity Baumé should be heated to just below its vaporizing point, in order to reduce its viscosity and to obtain the highest efficiency of combustion. Heavy California oil vaporizes at 230°'F., Mexican crude oil at from 175° to 210° F., and Beaumont, Texas, oil at 142° F. Fuel oil vaporizes at 130° F.

Jan 8, 1915

By Walter W. Bradley

(Three, papers included, in this discussion are classified as Mining Geology and also as one of the following-A, Metal Mining: B, Milling and Concentration: L, Geophysics. These papers are TP 2255, TP 2092 and TP 2038.) CONTENTS [PAGE Review of Fluorescence as Applied to Minerals, with Special Reference to Scheelite. (TP 1967 by J. W. VANDERWILT, Min. Tech., March 1946. Discussion by WALTER W. BRADLEY) I Geologic Interpretation of Magnetic Exploration on the Mesabi Range, Minnesota. (TP 2038 by R. B. H. JONES, Min. Tech., July 1946. Discussion by ROBERT B. SOSMAN) I A Technique for Photographing Difficult Subjects through a Petrographic Microscope. (TP 2092 by DONALD W. SCOTT, Min. Tech., Nov. 1946. Discussion by HORACE WINCHELL) 2 The Search for Concealed Deposits-a Reorientation of Philosophy. (TP 2146 by SAMUEL G. LASKY, Min. Tech., May 1947. Discussion by T. M. BRODERICK)3 Occurrence of Lead-zinc Ore at Iron King Mine, Prescott, Arizona. (TP 21 go by H. F. MILLS, Min. Tech., July 1947. Discussion by HUGH M. ROBERTS)3 Geologic Relations and New Ore Bodies of the Republic District, Washington. (TP 2197 by LAWRENCE B. WRIGHT, Min. Tech., July 1947. Discussion by AUGUSTUS LOCKE and J. A. RICHARDSON) 4 San Manuel Prospect. (TP 2255 by H. J. STEELE and G. R. RUBLY, Min. Tech., Sept. 1947. Discussion by L. KENNETH WILSON, ELDRED D. WILSON and the author) 5] Review of Fluorescence as Applied to Minerals, with Special Reference to Scheelite WALTER W. BRADLEY*-AS I recall, the first portable units for ultra-violet light of practical use with scheelite were developed at the Nevada-Massachusetts Tungsten Mine at Mill City, Nevada, and were used underground. Ultra-violet lamps are also installed there in the mill, above the gravity-concentration tables, for control observations. Geologic Interpretation of Magnetic Exploration on the Mesabi Range, Minnesota ROBERT B. SOSMAN*-When artificial precipitated magnetite is oxidized at a temperature in the vicinity of 100°C, the oxide is converted into a chocolate brown ferric oxide of the formula Fe2O3, free from ferrous iron, yet possessing the same magnetic susceptibility as the original Fe3O4. This form of Fe2O3 is variously called "ferromagnetic ferric oxide," " maghemite," or "gamma ferric oxide," and has been found as a natural mineral. If a body of magnetite in the Biwabik were to oxidize to this form, the oxidized and leached ore body might successfully conceal itself from Mr. Jones' survey by this ferromagnetic pretense. So far, gamma ferric oxide has not been found on the Minnesota iron ranges. I thought I had found some in the Hibbing pit in 1940, in a strongly magnetic specimen of soft ore differing in color from the prevailing hematite

Jan 1, 1947

By Carlos A. Aranda

The Smelting and Refining Department of Cerro de Pasco Corporation is located at La Oroya at an altitude of 3,720 meters (12,205 feet) in the Peruvian Andes. Producing lead, zinc and copper as well as twelve by-product metals and chemicals, the smelter is among the world's most complex. With the intake of high-bismuth ores in 1934, electrolytic lead refining by a modified Betts process was piloted and the plant went into commercial production in 1937 at a nominal capacity of 100 M.T. per day. After expansions in 1950 and 1963, nominal capacity has increased to 250 M.T. per day. Anodes spaced at 10.8 cm centre to centre and starting sheets are both set into the cells by overhead cranes. The asphalt-lined concrete cells are arranged in a Walker side-by-side configuration, and the electrolyte, circulating at 13 l/min./cell, is a solution of locally-produced hydrofluosilicic acid and lead fluosilicate. The corrosion cycle is limited to four days due to high impurity content of the bullion, which has successfully been treated at contents of up to 9% impurities. The cathodes are melted, drossed, and cast into blocks and pigs assaying 99.997 + % lead. The anodes with the blanket of slime adhering, are washed with electrolyte and condensate makeup water to remove the concentrated lead fluosilicate entrapped in the slimes. The slimes are then removed with high-pressure water sprays, centrifuged and sent to another plant for recovery of silver, gold, bismuth, selenium, tellurium, and antimony.

Jan 1, 1970

By Joseph Daniels

The Fritz Engineering Laboratory was built under the direction of John Fritz, and presented by him to the University. A view of the building, looking east, is shown in Fig. 1. The building was started in 1909, and completed in 1910, although all of the equipment was not placed until later. Mr. Fritz gave his personal attention to the details of construction and equipment, and it was his custom to drive over every day to the University from his home in Bethlehem and spend some hours watching the work, offering suggestions, making changes, and planning new work. The result is a building and an equipment which embody his practical ideas. The laboratory structure is of the steel mill-building type, of light-colored brick, 91 by 114 ft., of which a section is shown in Fig. 2 and the floor-plan in Fig. 3. The steel frame carries the roof and traveling crane-way. Ample light has been provided by numerous windows in the side and end walls, in the clerestory, and by a skylight 84 ft. long and 9 ft. wide in the north roof. The main aisle of the building is 49 ft. 2 in. between centers of crane-columns, and has a clear height of 40 ft. The remainder of the width is taken up by two side aisles, 18 ft. high. The laboratory consists of four sections: (1) A general testing-section containing the testing-machinery, a small machine shop, and an office; (2) a cement-testing room; (3) a room for making and storing concrete test-specimens; (4) a hydraulic section.

Jan 1, 1912

By M. S. Seltzer

In a previous paper1 it was shown that activation energies for steady-state creep in lead sulfide single crystals varied with the concentration of electronic defects. For n-type lead-excess crystals, values for the creep activation energy, Qc, decreased from 2.9 to 2.2 ev as the carrier concentration increased from 1017 to 1017 electrons per cu cm, while Q, increased from 1.6 to 2.3 ev for p-type sulfur-excess crystals as the concentration of holes increased from 6 X 1017 to 1018 per cu cm. It was also shown in Ref. 1 that the Q, values could best be correlated with the sum of the self-diffusion activation energies in PbS, i.e., for a given concentration of electrons or holes Q, = QPb + Qs, where Qpb and QS are the activation energies for diffusion of pb210 and s35 in PbS. This result suggests that creep rates are controlled by at least two atomic defects, one for lead migration and one controlling sulfur transport. It would be most desirable to interpret these creep energies in terms of an atomic defect disorder model for lead sulfide. Studies of creep rates as a function of sulfur pressure2 indicate that the defects controlling creep rates are singly ionized lead and sulfur vacancies, VPb and Vs. This hypothesis can be more firmly established by determination of Q, under conditions of constant atomic defect concentration rather than constant electronic defect concentration as has been previously done. Therefore, several measurements have been made of Q, on crystals whose con- centration of lead vacancies or sulfur vacancies has been fixed by equilibration under appropriate sulfur pressure and temperature. It was indicated in Ref. 2 that high-temperature isotherms are available which show how the concentrations of various atomic point defects in PbS vary with composition over the entire homogeneity range for the compound. Two such isotherms are shown in Fig. 1 for 900" and 1000°K. Utilizing these isotherms the concentration of a given defect, say Vbb, may be held constant over a particular temperature range by adjusting the sulfur pressure as the temperature is changed. Thus the concentration of one defect suspected of controlling creep rates may be held constant while other defect concentrations vary. The apparent activation energy for formation of these defects can be obtained from the isotherms giving their concentration as a function of sulfur pressure. Activation energies for creep obtained under conditions of constant defect concentration can then be compared with defect formation energies and certain possible atomic defects can be eliminated as creep-controlling species. We have performed creep experiments as a function of temperature at a stress of 244 g per sq mm under conditions which fixed the lead vacancy concentration, V', at 1016, 3.2 x 1016, and 3.2 x 1017 cm-3, and one were the sulfur vacancy concentration, Vs, was held at lo17 cm-3. The results are presented in Fig. 2 as creep rate, k, vs reciprocal of absolute temperature, 1/T. Specimens 34, 35, and 36 were deformed under constant lead vacancy concentration while specimen

Jan 1, 1969

By Hansheinz Portisch, Harold Margolin

A surface expansion was found to occur sometime after etching in Ti-A1 alloys containing 9.5 to 12.5 wt pct Al. The structure formed, grew, and disappeared with tzrrze. The surface expansion was followed by microscope observations and interferometric and lattice parameter measurements. Activation energy measurements for the growth of the "expansion structure" and chemical analysis indicated that the phenomenon occurred as a result of hydrogen pzckup during etching. It is proposed that hydrogen initially enters octahedral sites of Ti3Al coherent with a Ti and later shifts to the tetrahedral sites. It is postulated that expansion occurs when hydrogen enters the tetrahedral sites. The expansion structure disappeared, it is proposed, because of diffusion of hydrogen from the surface into the body of the alloy and because of loss of coherency of Ti3Al. In examining Ti-A1 alloys, Ence and arolinl observed markings on the surface of specimens. These markings did not appear after electropolishing only, but rather appeared only after etching. The markings appeared to grow as a function of time after etching and later seemed to disappear. Although the markings had some similarity to precipitates, showing, frequently, a Widmanstatten type of arrangement, the observation that other microstructural markings continue to be seen within the new structure suggested that it was actually not a precipitate. The source of this structure was unknown and an attempt was made in the present investigation to develop some understanding of its nature. It has been labeled expansion structure. 1) EXPERIMENTAL PROCEDURE A) Alloys. Alloys in the range 6.5 to 14.5 wt. pct A1 were studied. Bars, 4 in. sq, forged from Bureau of Mines (73 Bhn) titanium consumably arc-melted 4-lb ingots,' as well as 50-g arc-melted buttons of desired aluminum contents were used. The 50-g buttons also used Bureau of Mines titanium (73 Bhn) and aluminum of 99.99 pct purity. Buttons containing up to 8.5 wt pct A1 were hot-rolled from a furnace at 900' . Those with higher aluminum contents were hand-forged on a titanium anvil, and heated with an oxygen-hydrogen torch in the region of 1200" to 1300°c. Frequent reheating kept the samples at the desired temperature range. After a reduction of about 30 pct, the samples were water-quenched. To eliminate any contamination picked up either during hot rolling or forging, at least 1 mil of the surface of the sample was taken off. B) Heat Treatment. Prior to heat treatment all alloys were vacuum-annealed to remove hydrogen. Samples were annealed at 900' until a vacuum of 10'5 mm Hg was established. After this treatment, the samples were wrapped in molybdenum sheet and heat-treated in argon-filled quartz capsules, which were broken under water or iced brine at the conclusion of the heat treatment. All heat treatments under dynamic vacuum were performed in a rapid-quench furnace. This consisted of a molybdenum-lined quartz tube attached to a vacuum system and through a stopcock to a beaker of water. At the completion of the heat treatment the vacuum stopcock was closed, the furnace shut off, and dropped below the quartz tube. Then immediately the inlet stopcock was opened and water admitted until the tube was filled. The steam formed was allowed to escape through the inlet stopcock. This method was used in heat treatments up to llOO°C. C) Metallography. Specimens for metallographic examination were ground, then electropolished using a Disa Electropol machine with a perchloric acid electr01te. Specimens were etched with R-etch.3 A standard etching time of 3 min was used, with the specimen being agitated during immersion. D) Sample Preparation for X-ray Analysis. Samples 0.2 to 0.5 mm in diam were produced from heat-treated rods which were turned to 2 mm diam on a lathe and then rotation-etched. An etchant consisting of 1 pt HF, 7 pt HN03, and 12 pt HzO was satisfactory. With the rod rotating in a vertical position at 50 to 100 rpm, a needle with uniform dimensions could be obtained. Care had to be taken to insure that the rod was at the center of rotation, otherwise cavitation developed. If a small unevenness developed, it was possible to grind it off with a fine emery paper. E) X-ray Diffraction. All X-ray work was done on a North American Phillips X-ray diffraction apparatus and a Jarrell Ash microfocus X-ray unit. The Phillips unit was used with a copper target and nickel filter. The Jarrell Ash unit was fitted with a cobalt target and iron filter. For the Phillips unit 35 kva and 20 ma were used, whereas for the microfocus unit with the 100-p fixed-focus gun 40 kv and 1.5 ma were used. It was found that alignment of cameras on the Jarre11 Ash unit was very critical. The X-ray beam contains an intense area which is not the beam center. The cameras were aligned with the intense region by monitoring the beam coming out of the camera with a Geiger counter. Adjustments were made until a maximum intensity was obtained. A Phillips diffractometer with a Brown chart recorder furnished some of the lattice parameter data. The divergence slit up to 80 deg 28 was I deg; above 80 deg, a 4-deg opening was used, while the scatter slit was1 deg and the receiving slit had a 0.003-in. opening. The general scanning rate was 1 deg per min, while peaks of special interest were rescanned at -j deg per min. For elevated-temperature X-ray diffraction a Uni-cam High Temperature Camera with a film diameter

Jan 1, 1969

By V. H. Wilhelm

The trend initiated in January 1936, of stabilized gasoline prices, increased demand and extraordinary drilling activity, continued in California during the year 1937. Crude prices were maintained during the year at the highest level since September 1930. Wildcat activity with resultant new discoveries and development of proven acreage were greater than in any year since 1928. Many fields in California in former years have been produced at full capacity, with consequent loss of reservoir energy, but at the present time continued activity is maintained to develop adequate reserves, so that production in these fields can be taken at a rate to correspond with good operating practice. Naturally, this good operating practice will be influenced to some degree by gas outlets and, in certain instances perhaps, by oil outlets. In any event, these last two controlling features will result in favorable rather than detrimental operation. In fields producing from great depths, ultimate production will be practically limited to the flowing and compressor life of the well, since there is as yet no economical method for pumping wells below depths of approximately 7000 ft. Experience has shown, however, that such pumping difficulties will be overcome and that production secured by pumping will add some to reserves established on the flowing life of the wells. California continued to operate under voluntary curtailment, but with unlimited transfers of allowable between various fields. Even though there was at all times considerable production above the Umpire's established quota, a constantly increasing demand reduced storage during the year. This increasing demand was due mainly to the rapid rise in Pacific foreign shipments from May to September. It is questionable, however, whether this favorable condition will be maintained over a prolonged period. (See Fig. 1.) Field Discoveries The great drilling activity during the year resulted in the discovery of three new fields in the San Joaquin Valley, as well as many extensions

Jan 1, 1938

By W. B. Jamison

Man's material advance from one level of civilization to the next has involved the development of new, more useful tools and the utilization of energy greater than he alone could produce. These two essentials for material progress have developed at an ever increasing rate in the last century. While the first really successful use of mechanical energy derived from burning fuel was in James Watt's steam engine which pumped water from coal mines in Cornwall about 1770, there was still very little use of mechanical energy in mining by 1900 except for pumping and hoisting. Compressed air, having some of the characteristics of steam and which operated engines not unlike steam engines or steam hammers, powered the first attempts to mine coal with energy greater than human muscle could provide. When direct current-powered traction cars replaced horse-drawn transportation cars on city streets, it was natural that direct current locomotives should begin to replace animal and human power in mine haulage. Slowly, trolley and battery locomotives were developed and introduced. With d-c systems being established for haulage, it was natural that improved cutting machines should be developed and powered by d-c motors. Thus began the years of

Jan 1, 1961

By B. C. Allen, W. D. Kingery

Surface tension and its temperature dependence have been determined for pure liquid Fe, Cu, Co, Ni, and Sn and for Fe-C, Co-C, and Ni-C alloys. The temperature coefficient of surface tension is negative for all these liquids. The surface tension and wetting behavior of tin and tin-titanium alloys on A120,, Si,N,, MoSi,, and Sic, as well as the behavior of titanium-containing nickel alloys on A1 20, have been determined over a wide temperature range. For all the solids investigated titanium additims markedly lower the contact angle. Some limits for the solid-surface energies have been calculated from liquid surface tension and wetting behavior. SURFACE tension and interface energy are important variables in a number of metallurgical and ceramic phenomena, and have been discussed at some length in connection with determining micro-structure of polyphase systems,' solid-state sintering,' thermal etching of grain boundaries, heats of solution and fine powders,'1 grain-growth phenomena,' the mechanical behavior of fine foils and fibers, nucleation, soldering and brazing,' and other phenomenz of academic or practical interest However, until recently few quantitative data have been available for high-temperature systems. Among available data are some indicating positive temperature coefficients for the surface tension of liquid copper,*,11,'2 cast iron,l3 and iron-carbon14 alloys. Although carbon was found to be not surface active in iron at 1570" some preliminary studies had indicated the possibility of a positive temperature coefficient for the eutectic composition at lower temperatures.16 One part of the present study has been largely concerned with determining the temperature coefficient of surface tension for several metals at elevated temperatures, In addition to surface-tension studies, the wetting behavior of alloys containing titanium has been investigated over a wide temperature range. Previous measurements indicated that titanium was selectively adsorbed from nickel at a liquid nickel-solid alumina interface,17 and the use of titanium hydride or titanium-alloy techniques for metal-ceramic soldering is well known. In the present study, previous data have been extended to new alloy systems, and measurements have been carried out with other oxidation-resistant ceramics. EXPERIMENTAL The sessile-drop method was employed to measure liquid surface tension and contact angle between liquid and solid, utilizing apparatus and techniques which have been described previously.'g The shape of a sessile drop depends on equilibrium between forces of surface tension tending to form a spherical surface of minimum area and forces of gravity tending to flatten the drop. Typical sessile drops are shown in Fig. 1. From precise measurements of maximum drop diameter and drop height the surface tension and drop volume were calculated. Four solid materials were employed as supporting plaques for the liquid-metal drops. Aluminum oxide (99.9 pct, J, T. Baker, reagent grade) was pressed and sintered at 1800°C. Molybdenum-disilicide powder (99.0 pct, Electro Metallurgical Co.) was pressed and sintered at 1650°C. Plaques were cut from silicon carbide (99.4 pct, hot-pressed at Alfred University) and silicon nitride (95.1 pct, with Al, Fe, 0 as major impurities, Norton Co.) rods. All plaques were polished, cleaned, and dried prior to use. A number of metals and alloys were employed. Chemical analyses of vacuum-melted ingots of iron, nickel, cobalt (National Research Corp.), commercial nickel-base alloys, electrolytic copper (International Smelting and Refining Co.), and tin (Mal-linckrodt Chemical Works) are given in Table I. Alloys were prepared in the laboratory by vacuum melting the base metal with either titanium hydride (Metal Hydrides, Xnc.) or spectroscopic-grade carbon (National Carbon Corp.). Nickel-titanium alloys contained between 0.001 and 0.005 pct oxygen and the ferromagnetic metal-carbon alloys contained 0.001 pct. Cylindrical metal specimens (1 to 2.5 g) were machined and bevelled at the bottom to insure a uniform advancing contact angle on melting. Before use the samples were acid-etched, cleaned with acetone, and rinsed in petrol ether.

Jan 1, 1960

By W. P. Sykes

SEVEN years ago, Dr. S. L. Hoyt1 presented a masterful discussion of the hard metal carbides and cemented tungsten carbide. His lecture summarized most of the data then available in the field; many of the details relating to the production, properties and structure of cemented tungsten carbide had never been previously published, for, in fact, this information was only then being acquired. During the intervening years, the cemented carbides have assumed a place of real importance in the commercial field, with an ever widening variety of applications due to constant improvement in the control of production technique and the unremitting search for new compositions that might better the performance of the alloys in one or another type of service. The most recent summary of production methods, properties and guides for the successful application of the cemented carbides appears in the 1936 edition of the Metals Handbook. Of necessity, much detailed information relating to structures and physical properties is not included in such a summary, and it is with such details that the present discussion is concerned.

Jan 1, 1938

By E. C. Reed

Oil was discovered in Nebraska on Nov. I, 1939, when the Pawnee Royalty Company's Boice No. I well, about 3 miles west of Falls City (NE 1/4 NE 1/4, sec. 18, T.r N., R.16 E., Richardson County) was drilled into the Hunton formation but the develop-ment of the area took place during 1940. After a pumping test lasting 18 days, the Boice well stopped producing and failed to qualify for the State bonus of $ 15,000 offered for the first oil well to produce go bbl. per day for 60 consecutive days. On May 9, 1940, the Pawnee Royalty Company's Bucholz No. I well was completed about M mile southeast of the discovery well and flowed at the rate of about 330 bbl. per day, easily meeting the State bonus requirements. In addition to the discovery well, which later was reconditioned, and the bonus well, 28 producers were drilled in the Falls City field during 1940. Of these wells, 23 are in sec. 20, two are in the northern part 'of sec. 29, two in the southwestern part of sec. 17 and three in the eastern part of sec.

Jan 1, 1941

By E. C. Reed

Oil was discovered in Nebraska on Nov. I, 1939, when the Pawnee Royalty Company's Boice No. I well, about 3 miles west of Falls City (NE 1/4 NE 1/4, sec. 18, T.r N., R.16 E., Richardson County) was drilled into the Hunton formation but the develop-ment of the area took place during 1940. After a pumping test lasting 18 days, the Boice well stopped producing and failed to qualify for the State bonus of $ 15,000 offered for the first oil well to produce go bbl. per day for 60 consecutive days. On May 9, 1940, the Pawnee Royalty Company's Bucholz No. I well was completed about M mile southeast of the discovery well and flowed at the rate of about 330 bbl. per day, easily meeting the State bonus requirements. In addition to the discovery well, which later was reconditioned, and the bonus well, 28 producers were drilled in the Falls City field during 1940. Of these wells, 23 are in sec. 20, two are in the northern part 'of sec. 29, two in the southwestern part of sec. 17 and three in the eastern part of sec.

Jan 1, 1941

By F. M. Drake

IN this paper I propose to describe a plant which I lately erected for the Mount Stewart Lead and Silver Mining Company of Leadville, New South Wales, Australia. I am indebted to Mr. W. F. Burrow, of the Roads and Bridges Department of New South Wales, for the drawings which I present herewith, he having reduced and assembled them from my working drawings. The works are situated on a sloping hillside, but sufficient fall mas not available to have the furnace as high as desired, and at the same time have a good slag-tip and sufficient depth on the ore-floor to store a supply of ore and flux. The ore is delivered on the ore-floor (which is of the full width of the furnace-building, and extends back into the hill a distance of seventy feet) by two overhead tramways (not shown in the drawings), one on each side. From these the ore-mixture is made up on one side, while it is being taken to the furnace from the other. The fuel also is delivered by these tramways. The fluxes are stored on a floor directly at the back of the boiler and engine room. The boiler is a Cornish one, 6 feet 6 inches in diameter by 25 feet long. Its flue is 3 feet in diameter and does not contain Galloway tubes. The working-pressure is 40 pounds per square inch. The engine is an old-fashioned one, with a cylinder 16 inches in diameter by 30 inches stroke. Both the engine and boiler had been part of the plant of a defunct gold-mining company. They were very extravagant in their consumption of fuel. The blast is supplied by a rotary pressure-blower, of the Baker pattern, made in England. It has a capacity of 60 cubic feet per revolution. The furnace, which has several novel points, is shown in detail in Figs. 1, 2 and 3. The jackets are of cast-iron, and are higher than those generally used. They are different, too, in that the feedwater inlet is through a hand-hole plate near the bottom. This plate is fastened to the jacket by stud-bolts, and is provided with a baffleplate, which prevents the cooling water from impinging against the inner plate. The outlet is by a goose-neck at the top, which dis-

Jan 1, 1893

By C. G. Dunn

Many investigations have been made concerning the nature of plastic deformation and recrystallization of metals either in the form of polycrystalline materials or in the form of single crystals. However, similar work on strip materials composed of large grains as thick as the strip and having a high degree of preferred crystal oricntation has not been carried out extensively. Such materials are ideal not only for studying changes in single crystals under conditions where neighboring grains exert their influences but also for obtaining the complete change in orientation of a grain or group of grains during the course of plastic deformation and subsequent recrystallization. It is well known that first-order twins in the form of Neumann bands may be produced during the plastic deformation of ferrite crystals, particularly silicon ferrite crystals.l--3 Furthermore, it is believed that high-stress regions exist in the vicinity of these bands4. and it has been said that these banded regions would be active in recrystallization processes.5 Evidence to that effect in silicon ferrite had already been presented with photomicrographs showing recrystallization among Neumann bands during the early stages of recrystallizati~n.5,6 Similar evidence has been published for nonferrous metals5 Merging of fine parallel deformation bands during annealing to form twin bands of ordinary appearance in alpha brass has been offered not only as evidence of an active role being played by mechanical twins but also as evidence that such twins cxisted prior to recrystalli~ation.5 Proof that such new structures are actually first-order twins, or even twins at all, must be considered inadequate except for those cases where X-ray or optical data have been obtained to confirm the necessary oricntation relationship.7,8 A. B. Greninger has obtained excellent iliustrations of annealing twins in alpha iron.9 Since his material was previously deformed by sharp hammering, a process that generally induces Neumann bands, the existence of twins following annealing might suggest that they grew from mechanical twins. In connection with transformation twins in alpha iron, Greninger reported that grains containing three twin orientations occurred rarely and none occurred with three sets of well-developed bands.9 The work at the Pittsfield Works Laboratory on silicon ferrite in the form of large-grained strip steel deformed a small amount and annealed to partially recrystallize the grains indicates that the deformation and recrystallization processes that lead to annealing twins involvc more complex processes than the formation of Neumann bands and the growth of such bands. Some groups of annealing twins are obtained which contain not only three well-developed twin structures, but also contain more than one order of twins. It is also shown, in one case, that an interrelated group of twins did not arise within one single parent grain and, furthermore, orientations of grains in the group

Jan 1, 1944