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By J. T. Eash, E. M. Wise

MANY of the platinum metal alloys are hot-forged in the early stages of reduction from ingot and substantial quantities of platinum alloys are commercially employed at very high temperatures in ammonia oxidation units, orifices for forming glass rods and fibers and as cathodes in long-life thermionic amplifiers. They are used also for electrical heating resistors, safety blowout disks, thermocouples and crucibles. The tensile properties at elevated temperatures are important in many of these situations but data on the subject are limited. Creep data also are important, but will not be covered at this time. SCOPE AND CONCLUSIONS Tensile tests were carried out at room temperature and elevated temperatures up to 11000 C. on previously well annealed samples of platinum, palladium and several of their important alloys with compositions shown in Table 1. The results are presented graphically in Figs. 1 to 4. The tensile strengths of platinum and the platinum-base alloys (with the exception of the 10 per cent rhodium-platinum alloy) at 1100° C. are from 16.6 to 18.8 per cent of the strengths of the same alloys (well annealed) at room temperature. The strength ratio of the 10 per cent rhodium-platinum alloy is 22.3 per cent, which is appreciably higher than that of the- other materials tested. The tensile strengths of palladium and the palladium alloy at 1100° C. are from 10 to 11.2 per cent of the room-temperature values. The elongations of platinum and its alloys tend to increase at tempera¬tures above 600° to 800° C., while the two samples of pure palladium show a maximum at 600° C.

Jan 1, 1938

By H. Wilhelm, E. L. Davis, W. A. Clark

MATHEMATICAL formulas for the analysis of the behavior of producing oil wells can be devised which will be correct for the assumed conditions. However, in an oil zone, variables always exist which are unknown, or to which. it is impractical to assign mathematical values. It seems apparent that one should reason back from observed facts to an analysis of causes, rather than start with a hypothetical reservoir with assumed properties and attempt to explain observed phenomena. In this paper we hope to throw some additional light on factors influencing production, especially edgewater behavior. OIL and gas are contained in reservoirs of either the sealed type or the edgewater type. In the former all the recoverable oil is produced by gas expansion only. In this type of reservoir, edgewater is not effective. This may be because of faulting or overlapping strata, or more often, probably, the edgewater pressure is ineffec¬tive on account of resistance or lack of head.

Jan 1, 1933

Established as a Division September 27, 1949 LeRoy Scharon, Chairman C. M. Cooley, Secretary 29 West 39th Street New York 18, N Y

Jan 1, 1952

By J. L. Dumanoir, Maurice Martin

The induction-electrical log is a combination of a SP curve, a short normal curve, and an induction log; all three logs being recorded simultaneously in a single run. The spacing of the short normal is 16 in. The induction log is designated as 5FF40, which means that the sonde involves five coils and a focusing system, and that the distance between the main coils is 40 in. Examples of induction-electrical logs are shown in Figs. 13 and 15. The right-hand track contains the induction conductivity curve. The scale of this curve is linear with the units of conductivity, i.e., mhos/m or millimhos/m (mmhos/m), increasing from right to left. The same curve can be read in the reverse direction as a resistivity log, with a hyperbolic scale. In the middle track, the solid curve represents the short normal. (An amplified short normal is also shown in Fig. 15). The dotted curve is the resistivity curve of the induction log, i.e., the reciprocal of the conductivity curve, recorded with the same linear scale as the short normal. The SP is in the left-hand track. In this combination, the SP curve and the 16-in. normal are the essential correlation curves, as in the conventional electrical log. The induction log provides a more accurate and detailed record of formation boundaries than the conventional log, especially in hard rock territories. Furthermore, the induction-electrical log makes possible the determination of fluid content, particularly in thin beds—at least qualitatively and very often quantitatively. In such thin beds, because of the adverse effect of the adjacent formations, the responses of the conventional devices are generally doubtful and/or incom-plete. Another advantage of the new combination is that the induction log is little affected by the presence of thin hard streaks interbedded within the permeable sections, whereas such occurrences are the cause of serious distortions of the long normal and lateral curves. The evaluation of saturation from any resistivity log implies the knowledge of the true resistivity R, of the bed and of the resistivity R.. of the flushed zone, or at least of the ratio Rxo/Rc. With the induction-electrical log run in fresh mud, the 16-in. nor-mal has a smaller radius of investigation than the induction log, so that the former reads closer to R.. and the latter closer to Rt. Thus, it has been observed that the ratio of the 16-in. normal to the induction log readings can be used as a basis for the interpretation in terms of saturation, with the help of appropriate charts. The purpose of the present paper is essentially to explain this procedure and to provide the corresponding charts. On the other hand, when a formation is deeply invaded, the response of any log (in particular the induction log) depends upon the radial distribution of formation resistivities behind the wall of the hole, which itself is a function of the arrangement of the fluids saturating the formation pore spaces. This paper, accordingly, will begin with a schematic description of the distribution of fluids and resistivities in the invaded zone. Next, some essential characteristics of the induction log will be reviewed. Finally, the determination of the interpretation charts and their application will be explained. The discussion will be confined to the case of fresh muds, i.e., muds whose resistivity is at least five times as great as that of the formation waters. With the present equipment the induction log is not well adapted for logging in salty mud. The Laterolog and guard electrode log are at their best under conditions of low resistivity mud. Accordingly, when these tools were introduced a few years ago, the use of salty mud was recommended. Now, with the introduction of induction logging, spe-

Jan 1, 1958

The meeting of the Institute of Metals Division was held in Phila-delphia from Sept. 30 to Oct. 2, inclusive. On Monday evening preceding the meeting, a dinner was held at the Ritz-Carlton Hotel at which many of the former officers of the Division and of the present officers and execu-tive committee were present. The subject of a membership committee was discussed and a motion to appoint such a committee with powers to go over the membership list for the selection of divisional members and to institute plans for additional members was passed. Mr. H. E. Howe and Dr. Johnston of the National Research Council attended the meeting and presented their plans for an Alloys Research Association. Many opinions were voiced as to the practicability of such a scheme and Mr. Howe expressed himself in appreciation of the cooperative thought and efforts given him. On Tuesday morning the Institute of Metals Division joined sessions with the American Foundrymen's Association and listened to the opening addresses. In the afternoon a boat ride was taken on the Delaware River, visiting the plants of the Cramp Ship and Engine Building Co. and the shipyard of the Emergency Fleet Corpn. at Hog Island. The launching of the boat christened "Afoundria" at 5 p.m. was witnessed by members of the party. The opening technical session was held on Tuesday evening at the Ritz-Carlton Hotel at 8 o'clock. The next session was held at the Ritz-Carlton at 10 o'clock on Wednesday morning and the final session at the same time and place on Thursday morning. The sessions were well attended and the discussion was good. The highly technical nature of some of the papers on the program was of special note. Taken as a whole the meeting was one of the most successful ever held. The follow-ing papers were presented:

Jan 11, 1919

By Richard Moldenke

ONE of the little-known characteristics of cast' iron, which neverthe-less has an important bearing on results where accuracy in machining-is essential, is the ability of this material to ease up internal strains when. .allowed to remain quiescent for a more or less extended period of time. At seems as if the molecules in such a casting, by virtue of their "mobility,? can adjust their relative positions to an extent sufficient to overcome some of the existing stresses. The following instance will perhaps give a fair idea of the condition a casting may he in when just shaken out of the sand. A very large sheave-wheel, after shaking out, was taken' outdoors to be, cleaned and made ready for turning up. It was leaned against the side of the building, but before much could be done an arm tore apart with a loud report. Investigation showed that the sun had been shining on the upper rim, this adding a slight strain to those already existing within the arm and thus overbalancing the strength of the metal in tension. Had this sheave been kept under cover for a while, or at least until machined, the-strains., would have eased off sufficiently to allow the sun to look upon it without disaster. It will not be necessary to multiply examples. Every engineer knows the danger of water-hammer in pipe lines, particularly if the latter are of cast iron. Every mechanic knows, or should know, that it is not good to strike a fitting that is under steam pressure. It will be necessary to say a few words on the "internal- strains" in castings-the so-called "casting strains" we hear so much about. We all know that to get a casting reasonably true to the dimensions wanted requires a slightly larger pattern. The usual allowance for gray iron is 1/8 in. to the foot (1 cm. per meter) and ¼ in. to the foot (2 cm. per meter) for white iron (all dimensions). This reduction in length, breadth and thickness in a casting is erroneously called "shrinkage." It should be called "contraction," as for practical purposes. it is simply the difference .in dimensions of the casting red-hot and cold.

Jan 2, 1917

By A. A. Brant

Mining men, quite as exploration minded as petroleum interests, are in the position where most of the exposed crustal portions of the earth have been examined, where the demand for metals is high and likely to continue so, and yet where, perhaps, the tools fail for the economic exploration of many of the possible mineral areas more deeply covered with drift, alluvium, and later formations. At the same time the incentive exists to create acceptable substitutes for many of the duties of metal. The problem of the economic exploration of possible mineral-bearing areas is hence a vital one. In oil exploration, the absence of surface or shallow occurrences and the high cost of test drilling has led to the intensive study of geophysical techniques. Hence the development of the seismic method with its high certainty factor and its adaptability to standardized procedure.

Jan 1, 1949

By AIME AIME

BERYLLIUM is one of the most interesting of the minor metals and distinctly a modern development, for until the last two decades it had practically no commercial importance whatever. Then it was discovered that when small quantities of it were alloyed with copper, a copper alloy of unusual and valuable qualities resulted. This is by far its major use-in the manufacture of strong, heat-treated copper-base alloys in which the beryllium content varies from about 0.3 to 2.5 per cent. Its second most important use, though much smaller, is in the form of oxide or other nonmetallic products in the fluorescent lamp, X-ray, cathode ray, and television industries. Certain beryllium salts have the quality, in common with several other materials, of transforming short-wave radiation and cathode rays to visible radiation. Such materials are commonly known as phosphors, and the beryllium salts are the most important phosphors now in use. The third largest use for beryllium is for ceramics, including refractories. Beryllium is also used in small quantities in the form of the metal itself.

Jan 1, 1943

By Forbes K. Wilson

"For his vision, determination, dedication, and leadership in the conquest of the remote and rugged Ertsberg and the technical and human barriers to its development and for his lecture ..." It is a great honor for me to be included among the Jackling Award recipients, many of whom have been close friends and associates. My subject is the development of the Ertsberg, a copper mine located 4' south of the equator, 70 miles (113 km) from the south coast of Irian Jaya---the easternmost province of the republic of Indonesia at an elevation of 12,000 ft (3658 m) in an area which was inhabited by a few "stone age" people when I first arrived there in 1960. Persistence, tenacity, immagination and innovation were all required to bring the Ertsberg into production. The technical, financial and political problems that have been faced over the past 16 years were unique in many respects. I hope that my paper will give some encouragement and help to future developers of mines in difficult and inhospitable surroundings.

Jan 1, 1978

By AIME AIME

As already announced in the January Bulletin, this publication will be issued during the coming year monthly instead of bi-monthly as heretofore. Among other reasons for this change, it is desired to effect thereby the earlier transmission to members of important papers, lists of candidates for membership, and other items of timely information. Spokane Meeting and Excursions. Further details of the' 97th meeting of the Institute have been sent to members in the Circular of May 8, 1909. For, convenience of the members a summary of the additional in¬formation is here presented. A special train of Pullman cars will leave Chicago about September 15. This train will be side-tracked at all places visited, and the sleepers will be available for lodging and the dining-car for meals during the entire trip, except during the Yellowstone Park tour. The general. cost of the trip per member will be $300, which includes transportation, berth, and meals for the entire trip from Chicago back to Chicago, almost 6,000 miles, and the tour through Yellowstone Park, occupying in all about 30 days. Special accommodations on the train will be furnished at the following, rates

May 1, 1909

By R. B. Mears, E. H. Dix, R. H. Brown

In the Institute of Metals Division Lecture of 1940, E. H. Dix, J~.(I)~ discussed the acceleration of the rate of corrosion by high constant stresses. Experimental data obtained on this subject at the Aluminum Research Laboratories and a theory compatible with these facts were included in that lecture. The present paper contains data and ideas subsequently developed at the Aluminum Research Laboratories. Dix pointed out that in order for acceleration of corrosion by constant stress to occur: (1) There must exist in the alloy a susceptibility to selective corrosion along more or less continuous paths, as for in- stance at grain boundaries, and (2) There must exist a condition of high stress acting in a direction tending to pull the metal apart along these continuous paths. Acceleration of corrosion rate by stress is not confined to any one alloy system. Table I lists some of the metals and alloys and some of the corroding environments in which acceleration of corrosion by stress was sufficient to cause cracking (stress- corrosion cracking). It will be noted that the variety of alloys in which stress-corrosion cracking has occurred is rather large. Also, it will be observed that

Jan 1, 1945

By J. T. Dewan

An experimental setup is described whereby the responses of Neutron logging instruments have been determined opposite formations of different porosities and under various borehole conditions. The results of these tests are presented in several charts which show how the Neutron log is affected by the following factors: hole diameter, casing, cement, salinity and weight of drilling mud, and position of logging tool with respect to the wall of the hole. The responses in the case of empty holes are also shown. A chart is furthermore presented which shows the shapes of the Neutron log, as a function of logging speed and time constant, at the boundaries between two formations with different porosities. These were derived mathematically using as a basis laboratory determination of the shape of the curve under static conditions, i.e. at very low logging speed. Corrections for the readings made opposite thin beds are given by these computations. The correction is found negligible under usual logging conditions for beds thicker than about 4 ft. INTRODUCTION The Neutron log is used in borehole surveys both for the delineation of porous formations and for the quantitative estimation of their porosities.1,2,3,4,5 It is common practice to calibrate the response of the Neutron log in terms of porosity values for each given geological unit by means of empirical comparisons between the deflections of the neutron curve and the porosity values given by the core analysis in a sufficient number of wells. Usually, the plots of the porosity values vs Neutron log deflections show a definite trend. It is therefore possible to trace an average line across the plotted points. This average line constitutes a calibration curve which can be used to evaluate the porosities from the Neutron logs in the other wells drilled in the same region. Futhermore, when the porosity values are plotted on a logarithmic scale and the Neutron log deflections on a linear scale, the calibration curve is practically a straight line. Accordingly the calibration curves are often determined by simply tracing a straight line between two points corresponding to two widely different porosities. Different choices are made for these two points, depending on local conditions. For example, one point will be defined by plotting the deflection of the Neutron curve opposite a formation known to be very tight, for which an average porosity value of 1 or 2 per cent is assumed. The other point may correspond to shale sections, to which a porosity of around 40 per cent is ascribed. The information provided by the eletrical logs — in particular the Laterolog, Limestone log or Micro-Latero-log — is also very often a help in the calibration of the Neutron logs. Empirical approaches such as these make possible the derivation of fairly reliable porosity values from the Neutron logs in many cases, at least in open holes and in essentially clean formations. There are, however, several causes of uncertainty which may sometimes entail appreciable errors. On the one hand, the Neutron log readings are influenced by the borehole conditions: hole diameter, presence or absence of casing and cement, presence or absence of drilling mud, characteristics of the mud, and position of the logging instrument with respect to the wall of the hole. The amplitudes of the curves opposite thin beds are furthermore atfected by the bed thickness,

Jan 1, 1957

By H. C. H. Darley

Particles of montmorillonite-type clays consist of plate-like clay crystals stacked face to face. Under certain conditions in a suspension, these particles disperse to individual platelets with the formation of diffuse double layers round each platelet. This action has a profound influence on the rheo-logical and other properties of the suspension. This paper describes a test for degree of dispersion and uses this test to correlate changes in dispersion with changes in viscosity and gel strength. The test is of practical value in determining and controlling dispersion in drilling muds. INTRODUCTION It has long been recognized that the hydration and dispersion of clays, particularly those of the montmoril-loilite type, strongly influences the rheological and other properties of drilling muds, but little has been done to measure either of these phenomena under conditions that exist in drilling muds. The hydration of clays as such has been extensively studied by those interested in clay mineralogy, but in drilling muds it is to be expected that dispersion is at least as important a factor as hydration because of the much higher water-to-clay ratios and the very high degree of mechanical agitation. The term dispersion as generally applied to colloidal systems means the subdivision of large particles to small. Particles of montmorillonitic clays, however, consist of plate-like particles stacked face to face. Dispersion of these aggregates to individual platelets may be expected to have an unusually large influence on the properties of the suspension because of the shape factor, the enormous increase in specific surface, and the pronounced surface phenomena exhibited by the crystal surfaces. It is this form of dispersion that is particularly considered in this paper, -and the term degree of dispersion is used to imply the number of platelets per particle. The term aggregation is used to denote the opposite of dispersion, the association of individual platelets face to face to form stacks. It is important, as Garrison' has pointed out, to distinguish between the deflocculation-flocculation phenomenon and the dispersion-aggregation phenomenon. Flocculation of clay suspensions is characterized by the formation of voluminous sediments that are stable under quite high centrifugal fields. This indicates an edge to plate association of particles to form an open network type of structure, which obviously will have quite a different influence on the properties of the suspension than aggregation of the platelets face to face. The work described in this paper was primarily concerned with developing a test for degree of dispersion in clay suspensions and by means of this test to follow changes of dispersion brought about by addition of electrolytes and to show the influence of dispersion on the rheological properties. The Clay-Volume Test This test is based on the assumption that the greater the number of particles per unit weight of clay in a suspension the greater will be the volume of sediment when it is flocculated under standard conditions and centrifuged. After considerable experimentation the following procedure was established: 1 cc of the test mud vigorously shaken with 100 cc of 1-N NaCl in an ASTM oil centrifuge tube and centrifuged for five minutes in an International No. 2 centrifuge at 2,000 rpm. When drilling fluids of different solids content are being compared, the clay volume is expressed in cc per gram of clay solids, but generally changes in dispersion in a given mud are being compared and it is more convenient to report as cc of sediment. The test is strictly a comparative test, so that it is not necessary to adhere to the conditions specified above, e.g., with field muds a stronger flocculant such as Al2(SO4)3 may be preferable to NaCl.

Jan 1, 1958

By H. E. Cline, D. F. Stein

A fine lamellar structure with interlamellar spacings ranging from 0.I to 3.7 was Woduced by high-speed directional solidification and used to study the interaction of dislocations with an array of bimetallic bound-am.es. The tensile flow properties were measured at elevated temperatures and the results interpreted in terms of an image force model. As the width of the plates decreases the strength increases according to a Hall-Petch relation, suggesting pile -ups. Considerable strengthening was also observed at elevated temperatures. In recent years composites containing a strong but brittle phase and a ductile but weak phase have been studied extensively in the search for a high-strength material with adequate ductility.' However, the strength of these composites has been limited to a volumetric average of the strengths of the component phases. In this paper we will show that a composite made by directional solidification of a Cu-Ag eutectic has strength properties that substantially exceed the strength of either of the metals in the composite, and an explanation for this increased strength will be presented. The Cu-Ag eutectic is a near ideal material to study for several reasons. The eutectic structure is made up of alternate plates of silver-rich and copper-rich phases with the same crystal structure.2'3 In addition, the mechanical and elastic properties of silver4 and copper5 are known over a wide range of temperatures and the eutectic microstructure is stable to nearly the melting point.6'7 Therefore, the properties of the eu-tectic are readily comparable to various theories involving the mechanical properties of copper and silver. The experiments consisted of producing directionally solidified Ag-Cu eutectic material, determining the structure and performing tensile tests at different temperatures and strain rates. EXPERIMENTAL A) Solidification and structure. A cylindrical ingot 2.2 cm in diam and 15 cm long was prepared from 99.999 pct pure materials and cast in argon. The ingot was placed in an alumina crucible and was direc-tionally solidified at 7 x 10"4 cm per sec in a Bridg-man apparatus in argon. Metallographic examination at both ends and along the length of the ingot showed a uniform structure that consisted of fine alternate plates of silver- and copper-rich phases. The plates were aligned parallel to the growth direction, as shown in the longitudinal section, Fig. 1, and were in small randomly oriented domains of parallel plates as viewed in a transverse section, Fig. 2. Four smaller ingots 0.175 in. in diam were solidified at speeds of 2Xlo-', 4.4 xlo-', 4.4 x 10-3, and4.4x10-4 cm per sec to produce a range of lamellar spacings. Replica electron micrographs were taken to resolve the individual plates as shown in Fig. 3. The copper-and silver-rich plates in the larger ingot were about

Jan 1, 1970

By E. H. Griswold

PETROLEUM production engineering is essentially the application of the laws of 'physics and mechanics to the production of oil. A true production engineer is one who can apply the principles of mechanics, hydraulics, thermodynamics, and other physical arts so as to facilitate' the efficient and economical recovery of oil. To this end he must have wide knowledge of practical field operations and a working knowledge of geology, with a thorough understanding of the underground state of the fluids which he seeks to control. Generally speaking, there have been two schools of production engineering, the California development and the Mid-Continent development. In California the preliminary production engineering was done by representatives of the U. S. Bureau of Mines and the State Mining Bureau, and was essentially subsurface work in regard to casing patterns, water shut-offs, and completion procedure, inasmuch as these were problems of the utmost immediate importance to the California industry. The oil companies were impressed with the value of such work and placed engineers, or more strictly speaking, engineering geologists on their field staffs. These men, realizing the need of further technical study in the mechanical phases of producing operations, added mechanical and mining engineers, and out of the blend developed what is now known as a production engineer.

Jan 1, 1932

By T. L. CONDRON

DURING the past fourteen months, this committee has had under consideration and study the subject of the licensing or registration of engineers. The fifteen members of the committee as appointed by Council, were selected from thirteen states, viz., Connecticut, New York, Pennsylvania, Ohio, Georgia, Louisiana, Illinois, Missouri, Iowa, Minnesota, Colorado, California and Washington, and therefore represent practically all sections* of the United States, as well as mechanical, electrical, mining, hydraulic, municipal, sanitary, railway and' structural engineering, and also colleges of engineering. The first work of the committee was to investigate the general subject and to collect, so far as possible, avail¬able material bearing upon the subject in hand,. in-' eluding opinions from many engineers as to the need or desirability of legislation, as well as copies of all state laws passed and proposed, having to do with licensing or registration of engineers, architects and surveyor, This preliminary investigation disclosed that very pronounced views were held by engineers throughout the country, both for and against state licensing or registration. The general sentiment one year ago was more opposed to such measures than it is today. The older members of the profession did not as a rule favor licensing nor did they feel there was need for state regulation of engineering practice, while among the younger men there was a feeling that licensing or registration by the states would add prestige to professional engineers and in many ways benefit -the profession, as well as individual engineers.

Jan 1, 1920

By David R. Mitchell, R. B. Hewes

MANY processes for cleaning coal that are in use depend primarily on physical properties of coal and refuse other than specific gravity and surface conditions relating to froth flotation. These properties are' shape, coefficient of sliding friction, resilience, friability, magnetic susceptibility, and electrical conductivity. In many of these processes specific gravity does have some effect and many separators are designed to utilize more than one of the physical properties cited. Although the processes described herein do not have a widespread application, yet for specific coals and specific conditions, they are economically important. A problem confronting many coal-mining districts is the marketing of the slacks or screenings and dust passing the final sizing screens. Proc¬esses in commercial use installed primarily to increase the form value, and hence the market value, of these slacks and dusts include briquetting, packaging, and low-temperature carborization. MECHANICAL PICKERS Machines utilizing shape, frictional resistance, and differences in resilience of coal and impurities are usually called mechanical pickers. They require a closely sized feed, therefore their use is confined to the pea, nut, and egg sizes. Various types of these devices are described by Berrisford, 1. 2 Taggart, and Yeele.

Jan 1, 1943

By Alfred Brooks

Introduction PETROLEUM seepages are known in Alaska at four localities, all on Pacific seaboard. These, named from east to west, are Yakataga, Katalla on Controller Bay, Iniskin Bay on Cook Inlet, and Cold Bay on the Alaska Peninsula. Besides these, a petroleum residue has been found near Smith Bay on the north Arctic coast of the Territory. At Katalla, Cold Bay, and Iniskin Bay there has been some drilling for oil, and in the first field several productive wells have been opened up. Alaskan petroleum so far as its composition is known, is a refining oil, with paraffin base and low sulphur content. Most of what is known of the geology of Alaska oil fields is based on the investigations of Dr. George C. Martin, of the United States Geological Survey. A. G. Maddren, of the same service, has recently made a reconnaissance of the Yakataga oil field. The data to be here presented are chiefly taken from the following publications: G. C. Martin: The Petroleum Fields of the. Pacific Coast of Alaska, with an account of the Bering River coal deposits, Bulletin No. 250, U. S. Geological Survey, pp. 9 to 27 (1905). G. C. Martin: Geology and Mineral Resources of the Controller Bay Region, Alaska, Bulletin No. 335, U. S. Geological Survey, pp. 112 to 130 (1908). G. C. Martin and F. J. Katz: A Geologic Reconnaissance of the Iliamna Region, Alaska, Bulletin No. 485, U. S. Geological. Survey, pp. 126 to 130 (1912). A. G. Maddren: Mineral Deposits of the Yakataga District, Bulletin No. 592,. U. S. Geological Survey, pp. 143 to 147 (1914).

Jan 2, 1915

By Margaret V. Doyle, R. W. Powers

INTERNAL friction measurements, carried out as functions of temperature, have been used extensively to obtain data on the mobility of interstitial impurities in the Group V metals, vanadium, colum-bium, and tantalum. For a given frequency of vibration, the internal friction peaks at a temperature which depends principally on the particular metal and interstitial impurity. Relaxation times and corresponding activation energies are determined from a knowledge of such peak temperatures for various vibration frequencies. These experimentally determined relaxation times are related to the average jump frequencies of the interstitial impurity atoms using the model of Snoek1 and can be related to macroscopic diffusion coefficients as shown by Polder.2 In these Group V elements, the impurity whose diffusion rate has been the hardest to pin down by the internal friction technique has been carbon. The experimental difficulties associated with carbon in these metals were not evident in the earliest investigation carried out by Ke on tantalum.3 The carbon peak was thought to occur near 140°C at 1 cps on the basis of the enhancement of the height of this peak measured on specimens which had been coated with colloidal carbon and heated in vacuo at 1200°C. Presumably on the basis of similar evidence, Wert identified a peak also near 140°C at 1 cps in columbium with the diffusion of carbon in that element." Later, the difficulties of admitting carbon into these metals without simultaneously introducing oxygen were pointed out by Ang and Wert- nd by Marx, Baker, and Sivertsen.6 The latter suggested that the peaks attributed to carbon in tantalum and columbium might arise from the presence of traces of oxygen, adventitiously absorbed during the carburization. Such suspicion was confirmed, at least in tantalum, when it was found possible to prepare C-Ta specimens without contamination by oxygen. Specimens sci prepared, aitnough high in carbon content, gave no evidence of a damping peak near 140°C.7 Recently, the authors were able to Show that carbon diffuses in tantalum at a rate only slightly slower than that for nitrogen.8 At 1 cps, the carbon peak lies at 34g °C, only a few degrees above the nitrogen peak at 341 °C. However, the two could be distinguished by a different stability with respect to aging at 400 °C and by a different dependence of peak height on solute concentration. On the basis of this experience with tantalum, it appeared worthwhile to search also for a carbon peak in columbium in the vicinity of the nitrogen peak." In this report, the location of the carbon peak in columbium is made known and its position relative to the nitrogen peak is compared with the authors' previous findings in tantalum. In addition, a second source of internal friction seen only in specimens of very high purity is discussed. Columbium was obtained from the Fansteel Metallurgical Corp. as either 30 or 40 mil diam stock. The manufacturer gives the following analysis as typical of this material: 99.4 pct minimum Cb, 0.10 pct maximum C, 0.5 pct Ta, 0.04 pct Ti, 0.02 pct maximum Si, and 0.01 pct maximum Fe. Wires 13 in. long were degassed near 2200°C for 4 to 16 hr in an ultimate vacuum better than 2.10" mm Hg in an apparatus described previously.8 This treatment reduced the oxygen and nitrogen damping peaks observed in the as-received material to less than 0.0001 in Q-1 above background. The latter value varied somewhat from specimen to specimen in the range 0.0004 to 0.0008, depending chiefly on the wire diameter and the frequency of vibration. The high temperature evacuation left the specimen in a rather soft condition, the Vhn being reduced to 40 from a value near 121 in the as-received conGi~iur~. The gram size was about the diameter of the specimen. After outgassing, specimens were loaded with carbon by absorption of such hydracarbons as methane or ethylene. Carbon was also added to a few speclrnens by heating them at

Jan 1, 1958

By Albert J. McIntosh

In discussing the petroleum products situation the first thing that comes to mind is "what is happening to gasoline." Is the consumption increasing? How is the export market? What about imports? Are stocks on hand too high? Have we produced too much? This paper will attempt to answer these questions. Consumption of gasoline (motor fuel) in the United States in spite of the depression and the chaotic conditions of many industries has increased during 1931 about 2 per cent over 1930. This favorable factor was offset by a severe contraction in exports, which fell off about 30 per cent from 1930. This drop in exports was so large that very little more export business was done than in 1926 or 1927. Taking all demand combined, there was a decrease from the peak year of 1930 of nearly 11,000,000 bbl., amounting to slightly over 2 per cent. The units of the industry, though, should have expected some decrease and governed themselves accordingly. Let us see what they did. They reduced imports over 3,000,000 bbl., which helped. Production was cut 3,000,000 bbl., but this was not enough, so that stocks increased 1,800,000 bbl. whereas during the previous year stocks were reduced 2,500,000 bbl. It is apparent, therefore, that something was done to keep the industry in balance in regard to gasoline, but not enough. If the year had ended on Sept. 30, we could have said that production had been cut 19,000,000 bbl. and stocks had been reduced from the previous year, but the excessive production during the last three months of the year changed everything. It is a strange thing and worthy of note that the price of gasoline fell to its lowest levels when apparently the greatest improvement was being made, and that during the last quarter of the year prices started to improve, when, in spite of an improvement in total demand which approximated 1930, an excessive production caused an uneconomic condition to set in. Stocks on hand on Dec. 31 were unquestionably too high, possibly 10,000,000 bbl. more than was needed for a strong condition to obtain. It seems almost unbelievable that the industry would continue to produce

Jan 1, 1932