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By R. E. Collins

The existence of fluid migration across fixed boundaries in oil and gas reservoirs has been known for many years. Several techniques have been developed in the past for estimating The rate of migration across fixed boundaries as an aid in planninng field development and in the valuation of oilfied properties. The principal de/errc7nt to the use of these techniques lies in the rather extensive reservoir and field data required for ca1cula1ion.s of fluid migration. For this reason, a new, simplified procedure has been developed which makes possible the calculation of fluid migration with a minimum of field and resrvoir data. This new technique is based on certain. solutions of the differential equations describing flour in the reservoir which assume, for the portion of the reservoir of interest, that the formation can be approximated by a homogeneous rock of uniforrn thickness, that only a Single mobile fluid phase exists, and {hut fluid production at the well is solely a result of expun.rioti of rile resersoir fluds. The results of the, present work are compiled in a set of curves. These curves can he used to calculate both rule and cummulative fluid migration when the abovc assumptions ore ju.r/ifiril. The only data required for such calcu1ations are the production hisrories of all wells in the field, the permeability and porosity of the reservoir., the, compressibility and viscosity of the fluid. and the shape of the reservoir, INTRODUCTION The migration of fluids across fixed boundaries in oil and gas reservoirs has long been recognized as an engineering and economic problem, but no methods for estimating the extent of migration during the development stage of a reservoir have been published. The investigation reported here has been directed toward providing a simple technique for estimating the extent of such migration and has therefore been restricted to the simple case of a homogeneous reservoir of uniform thickncss containing compressible liquids. It is assumed that only a single mobile fluid phase exists and that fluid production at the wells is solely by expansion of the reservoir fluids. Obviously, few, if any. reservoirs conform to these assumptions during their entire productive life. On the other hand, most reservoirs approximate fluid expansion reservoirs during their initial stages of primary production. Consequently, the present work should be applicable during the field development of most reservoirs, regardless of whether or not they ultimately are gas cap, dissolved-gas, or water-drive reservoirs. The mathematical analysis of this problem has been outlined in the Appendix, while the results of the investigation are presented in the following discussion. DISCUSSION OF CALCULATION PROCEDURE SLNGLE Well, Ini-iimite Reservoir The procedure for calculating fluid migrations is based on solutions of the partial differentia1 equations describing the flow of a homogeneous compressible liquid in a homogeneous reservoir of uniform thickness. This differential equation has the form of the well-known diffusion equation. The equation, as applicable to our problem, is where p is fluid density, is porosity, EL is viscosity, c is compressibility,* and k is permeability; .r, y and t are the space coordinates and time. Derivation of this equation is given in the Appendix. The analytical solution of this equation for a single well of negligible radius producing at a constant rate. q, from a reservoir of infinite areal extent for a time, 1. can he readily obtained. From this solution the rate of flow and also the cumulative flow across a straight line segment of length, 1, at a perpendicular distance. 6. from the well can be computed. One end of the line must be on the perpendicular joining the well to the

By R. C. Ku, R. G. Davies

The stress-strain behavior of Fe-C and Fe-Ni solid-solution alloys has been investigated at 25°C. It is found that the rate of solid-solution strengthening is dependent upon the strain at which the yield stress is measured, the macroyield stress being much more concentration-dependent than the microyield stress. In fact the addition of nickel does not lead to any increase in the microyield stress of iron. The primary effect of increasing the carbon or nickel content is to increase the slope of the stress-strain curve in the microyield region; this effect has been correlated, by means of transmission electron microscopy, with a decreased ability of the dislocations to cross-slip. It is concluded that the Mott-Nabarro theory is a good description of true solid-solution hardening in these and other iron-base alloys. A.LL theories of the solid-solution strengthening1-4 indicate that the flow stress of an alloy increases both with solute concentration and "misfit" between the solvent and solute atoms. The functional relationship between strength, solute concentration, C, and misfit depends upon the particular theory. Mott and Nabarro1,2 and Schoeck and Seeger3 both predict a linear increase in strength with concentration, while Fleischer4 indicates that the strength should be proportional to C1/2; there are in the literature experimental observations to support both these compositional dependencies.1'8 The experimental evidence used to support the theories is the change in macroscopic yield stress (strain, e, = 10-3) with composition. However, recent investigations have revealed that solid-solution strengthening in a Cu-Al single crystals7 and in Fe-V polycrystal-line" alloys depends upon the strain at which the flow stress is measured; a flow stress in the microplastic range (e = 10-6 to 10-5) is much less concentration-dependent than the macroyield stress. Since the theories of solid-solution strengthening are concerned in particular with the stress to move a dislocation in a dislocation-free matrix, they should only be compared with microyield-stress data; it will be shown that in a material deforming homogeneously the microyield stress (e = 10-6) is approximately the stress to move through the matrix those dislocations which have been nucleated by stress concentrations such as particles or grain boundary ledges.9-11 In contrast, the macro-yield stress is more complex in that it is affected by several phenomena: dislocation multiplication, dislocation interactions, and the ease of propagating slip across grain boundaries. For example, it is experimentally observed that when long-range order12'13 or solute effects10 restrict cross alip the grain boundary

Jan 1, 1967

SHELBY M. HARRISON,* New York, N. Y. (written discussion ?).¬Your secretary requested a brief description of the Russell Sage Foundation, in order that members of the Institute, if they should desire to avail themselves of it, would know what type of service is offered to them through our institution. The foundation was established in 1907 by the gift of Mrs. Russell Sage of $10,000,000 as a capital fund, the income of which is to be spent for the improvement of social and living conditions in the United States. One of the lines of activity which the foundation has felt would lead toward this end is the development and promotion of community surveys; and because the scope and methods followed in these surveys are very similar to the scope and method of much of the institution's work in general, an idea of its main activities can perhaps be given best by describing one of our surveys. Incidentally, it may be pointed out that antecedent to the survey stand at least two important facts: first, the recognition. that communities are active, not static forces, that they develop, that changes in. material and human relationships occur continuously, and that with them come new social and civic problems which must, in many cases, be diagnosed and prescribed for anew; and second, the reality of scientific advances along lines which make possible at least some measure of solution of the problems. Evidences of these changes are abundant; many of them are found in the rapid growth of cities in the last few decades. Villages in agricultural districts, places where everybody knew everybody else, where the pulpit had been long the chief or only influence molding public opinion, where the air was unclouded by the smoke from factory stacks, where the water supply was not affected by pollution, where sunlight and building

Jan 5, 1918

By A. U. Seybolt

A. U. Seybolt (General Electric Research Laboratory)— As pointed out in an earlier paper,41 it appears to be very difficult to nucleate Si3N4 in Si-Fe of silicon content up to around 5 pet. Therefore, one observes, as did Pearce, that equilibrations with nitrogen gas yield only nitrogen in solid solution at temperatures above about 700°C, or, as Pearce found, 770°C. Evidently, the free energy of formation of Si3N4 only becomes high enough at -770°C to overcome the reluctance of Si3N4 to nucleate. However, as mentioned in Ref. 41, if some Si3N4 is first formed by a mixture of ammonia and hydrogen, one can then replace this gas mixture by nitrogen gas, and either increase or decrease the amount of Si3N4 present at any temperature by suitable adjustment of nitrogen pressure: that is, to equilibrate with Si3N4. In the equilibration experiments cited in Ref. 41, equilibrium was approached from both sides, and it was found that samples up to 944oC, at least, were in equilibrium with Si3N4. Higher temperatures were not employed, as this would have necessitated a redesign of the apparatus for using nitrogen pressures in excess of 1 atm. To summarize, the results of Pearce's experiments and those of Ref. 41 cannot be directly compared because two quite different equilibria were studied. Therefore, the statement by Pearce on p. 1398 indicating apparent error in Ref. 41 is unjustified. M. L. Pearce (author's reply)— There was limited evidence obtained in the current investigation which would indicate that excessive "supercooling" did not occur. A small piece of the same resulting from heat treatment No. 5 in Table III was subsequently held at 800°C for 16 hr in 95 pet N-5 pet H. Isotope-

Jan 1, 1964

By James Hyslop

THE Pittsburgh seam in eastern Ohio has an average thickness of 5 ft and lies almost level Immediately above it is a layer of draw slate about 12 in thick, which normally has little structural strength, and is pulled down or allowed to fall as mining progresses Above the slate is a, variable thickness of roof coal, which in places will stand for the life of the working section and sometimes for the life of a secondary haulage entry The thickness of this roof coal varies from zero to 24 in In general, however, it does not provide a satisfactory roof, and usually is supported or pulled down About it is a mass of shale, soapstone and clay, of quite variable thickness, usually running from 5 to 8 ft and above this is a stratum of hard blue limestone, which provides a permanent roof Where entries are to be used for less than five years, the roof usually can be supported by wood or steel crossbars, but if they are to be used for a longer time, roof support is a serious problem All the roof material below the limestone disintegrates when exposed to air or moisture, and in a few years falls out between and over the crossbars Where this material is removed for a considerable height above the coal, the ribs scale and thus contribute to a further collapse of the roof As the height of the entry increases, cost of timbering is greatly increased, a problem that always is encountered where old entries are recovered or repaired METHODS During the last six years the Hanna Coal Co has used gunite for roof protection in mine entries Two general methods of guniting are practiced The first consists of the application of a I-in coating of unreinforced material This application does not provide any appreciable structural strength, and serves principally to protect the strata from exposure to air and moisture With the other method a coat at least 2 in thick is applied and provided with suitable reinforcing, which provides a structural strength proportional to the thickness of the coat and the reinforcing used The first method is adopted as a general practice, modified only where additional support is required "Gunite" is a mixture of cement, sand and water * The cement and sand are thoroughly mixed and screened before being fed into the hopper of a cement gun After the hopper lid is closed, compressed air is applied to force this dry mixture through the hose line to the nozzle, where the quantity of water needed to effect the proper hydration of the cement is added The coating is dense, and stronger than poured concrete

Jan 1, 1941

Jan 1, 1889

By E. C. Truesdale, Gerald Edmunds

A few years ago H. M. Cyr, working in the Research Laboratories of The New Jersey Zinc Co., produced a few pounds of zinc1 of such purity that no other elements were detected in it by spectrographic analysis, using the facilities then available. This zinc contained less than one ten-thousandth of one per cent of metallic impurities.&apos; During the decade that followed upon the laboratory production of this "spectro-graphically pure" zinc, commercial developments brought about the production of large tonnages of zinc of purity exceeding 99.99 per cent, and today zinc of 99.999 per cent purity is produced and marketed as "chemically pure" zinc. Typical analyses of present supplies of high-purity zinc are given in Table 1. Table 1.—Typical Analyses Percentnge by Weight Sum of Zinc Fe, Ib1 Fe Cd 1A1 cd Special High Grade*.......... 0.007b 0.005b 0.005b none O.OIOb C.P. (chemically pure)......... < 0.0002 0.0005c 0.000052 S.P. (spectrographically pure).. <0.0002d <0.00005d a A.S.T.M. Standard Specification for Special High Grade Slab Zinc (A.S.T.M. Designation: B 637). b Maximum. &apos; Fe chemically determined. Pb and Cd are spectrographically determined. d Differences between composition of C.P. and S.P. zinc are discussed later in this paper. The availability of commercial tonnages of special high-grade zinc has been the basis for the development of the zinc-base die-casting alloy industry which, in the year 1936, consumed one-eighth of the zinc used in the United States for all purposes. This and the C.P. and S.P. grades have given impetus to scientific investigations into the properties of pure

Jan 1, 1939

By E. C. Truesdale, Gerald Edmunds

A few years ago H. M. Cyr, working in the Research Laboratories of The New Jersey Zinc Co., produced a few pounds of zinc1 of such purity that no other elements were detected in it by spectrographic analysis, using the facilities then available. This zinc contained less than one ten-thousandth of one per cent of metallic impurities.&apos; During the decade that followed upon the laboratory production of this "spectro-graphically pure" zinc, commercial developments brought about the production of large tonnages of zinc of purity exceeding 99.99 per cent, and today zinc of 99.999 per cent purity is produced and marketed as "chemically pure" zinc. Typical analyses of present supplies of high-purity zinc are given in Table 1. Table 1.—Typical Analyses Percentnge by Weight Sum of Zinc Fe, Ib1 Fe Cd 1A1 cd Special High Grade*.......... 0.007b 0.005b 0.005b none O.OIOb C.P. (chemically pure)......... < 0.0002 0.0005c 0.000052 S.P. (spectrographically pure).. <0.0002d <0.00005d a A.S.T.M. Standard Specification for Special High Grade Slab Zinc (A.S.T.M. Designation: B 637). b Maximum. &apos; Fe chemically determined. Pb and Cd are spectrographically determined. d Differences between composition of C.P. and S.P. zinc are discussed later in this paper. The availability of commercial tonnages of special high-grade zinc has been the basis for the development of the zinc-base die-casting alloy industry which, in the year 1936, consumed one-eighth of the zinc used in the United States for all purposes. This and the C.P. and S.P. grades have given impetus to scientific investigations into the properties of pure

Jan 1, 1939

PETROLEUM DIVISION Established as a Division March 24, 1922 Paul R Turnbull, Chairman John R McMillan, Vice-Chairman Morris Muskat, Vice-Chairman William E Stiles, Treasurer Joe B Alford, Executive Secretary 408 Trinity Universal Building Dallas, Texas

Jan 1, 1952

By Henry M. Howe, Joseph Winlock, Francis B. Foley

This investigation was undertaken for the purpose of determining, in a systematic way, the effect of the rate of cooling of steels, heated to above the transformation range, on their various mechanical properties. This paper gives the results obtained in the investigation of the heat treatment of carbon steels carried out under the auspices of the Committee on The Heat Treatment of Carbon Steels of the Engineering Division, National Research Council. The objects of this committee, of which Dr. Henry M. Howe was chairman, were to increase knowledge of the influence of heat treatment on the mechanical properties of carbon steel. The mcthod pursued was to subject specimens of steel of the carbon contents most used for engineering work, 0.34 per cent., 0.52 per cent., and 0.75 per cent., to various heat treatments, and to test the mechanical properties thus induced. The steels were the same as were used by the committee on fatigue phenomena. This project was financed jointly by the U. S. Bureaus of Mines and Standards; industries and university laboratories have cooperated. A large part of the work was done at Doctor Howe&apos;s private laboratory. The committee consisted of F. B. Foley, H. AT. Boylston, H. C. Boynton, G. K. Burgess, H. J. French, J. H. Hall, Zay Jeffries, R. S. Johnston, F. C. Langenberg, H. F. Moore, E. H. Yeirce, H. S. Rawdon, W. E. Ruder and 11. J. Stagg. The work was undertaken at the suggestion of Doctor Howe, who thought, at the outset, that steel in the sorbitic state might have properties which, for most engineering purposes, would be better than those of the usual or pearlitic state. By a systematic variation in the heating

Jan 1, 1923

By Joseph Winlock, Francis B. Foley, Henry M. Howe

This investigation was undertaken for the purpose of determining, in a systematic way, the effect of the rate of cooling of steels, heated to above the transformation range, on their various mechanical properties. This paper gives the results obtained in the investigation of the heat treatment of carbon steels carried out under the auspices of the Committee on The Heat Treatment of Carbon Steels of the Engineering Division, National Research Council. The objects of this committee, of which Dr. Henry M. Howe was chairman, were to increase knowledge of the influence of heat treatment on the mechanical properties of carbon steel. The mcthod pursued was to subject specimens of steel of the carbon contents most used for engineering work, 0.34 per cent., 0.52 per cent., and 0.75 per cent., to various heat treatments, and to test the mechanical properties thus induced. The steels were the same as were used by the committee on fatigue phenomena. This project was financed jointly by the U. S. Bureaus of Mines and Standards; industries and university laboratories have cooperated. A large part of the work was done at Doctor Howe&apos;s private laboratory. The committee consisted of F. B. Foley, H. AT. Boylston, H. C. Boynton, G. K. Burgess, H. J. French, J. H. Hall, Zay Jeffries, R. S. Johnston, F. C. Langenberg, H. F. Moore, E. H. Yeirce, H. S. Rawdon, W. E. Ruder and 11. J. Stagg. The work was undertaken at the suggestion of Doctor Howe, who thought, at the outset, that steel in the sorbitic state might have properties which, for most engineering purposes, would be better than those of the usual or pearlitic state. By a systematic variation in the heating

Jan 1, 1923

R. F. McELVENNY.- Mr. Oldright has just given me a letter to read to you, which I think it may be of interest. It is headed, "Silver Meeting Dinner". The letter is as follows: "To Members of the A. I. M. & M E.: The annual business meeting and election of officers will take place at the University Club, Wednesday, May 28th, 1930 at 7 p.m., at the Silver Meeting Dinner. The Nominating. Committee for next year&apos;s officers have proposed the following names: Chairman, Robert Wallace; Vice-Chairman, G. W. Crane; secretary, C. T. Van Winkle, Other nominations can be made at the meeting. Utah being the leading silver producer of the United States, constructive suggestions regarding the silver situation will be made at this meeting which are new and of general interest to the members. The speak¬ers will be followed by a Round Table discussion of the silver situation and proposed remedies. Speakers will be - W. M. Ferry, President of the Silver Producers&apos; Association, &apos;Recent developments in the Silver Question&apos;.. Senator Frank J. Cannon, &apos;The Cannon Plan&apos;. George W. Snyder, &apos;The Manufacture of Sterling Silver.&apos; Discussion by J. J. Beason, G. W. Crane, J. 0. Elton, J. W. Wade and others. Members of the Conference on Copper Reverberatory Smelting are invited to be present. Chairman J. A. Norden will preside. C. T. Van Winkle, Secretary. Dinner will be $1.50 per plate." The next subject is "Boilers: Proper construction of, so as to secure best utilization of heat from gases, and facility in removing dust and clinker with minimum losses in operation." Who is particularly interested in that subject? The type of boilers is practically a standard practice now. I do not know of anybody that is using the tandem system now. No one is building a plant with a tandem system in it.

Jan 1, 1930

By E. H. Hamilton, H. C. Vacher

The limiting concentrations of carbon and oxygen which may CO-exist at equilibrium in liquid iron are important in determining the degree to which liquid steel may be refined before it is deoxidized. Most refining processes depend upon the oxidation of a highly carburized iron which invariably results in contaminating the steel with oxygen. The oxygen thus introduced presents many problems to the refiner, who in turn has attempted to rid the steel of this impurity by deoxidation witch elements such as manganese, silicon and aluminum. The importance of the limiting concentrations of carbon and oxygen is accentuated in view of a number of recent researches which have indicated in many instances the existence of relations between oxide inclusions and dissolved oxygen and physical properties and chemical behavior of steel. The determination of the equilibrium concentrations of carbon and oxygen existing in iron under steelmaking conditions is obviously of fundamental importance. It has been generally assumed that the product of the equilibrium concentrations of carbon and oxygen in liquid iron is a constant and that this product is directly proportional to the carbon monoxide pressure in equilibrium with the liquid iron. Hertyl.2 has computed values for this product based on open-hearth data which are all in the neighborhood of 0.01 to 0.03 (per cent. FeO X per cent. C) for temperatures in the vicinity of 1550" to 1600" C. and one atmosphere pressure. Kinzel and Egan % have attempted to determine the value of this product by exposing liquid iron to carbon monoxide at one atmosphere pressure. The value reported by them was 0.0005 at 1550" C. In order to apply certain equations to the rate of carbon elimination in the open-hearth process, Feild4 found it necessary to assume a value of 0.0102 at 1580" C. for this

Jan 1, 1931

By H. C. Vacher

THE limiting concentrations of carbon and oxygen which may co-exist at equilibrium in liquid iron are important in determining the degree to which liquid steel may be refined before it is deoxidized. Most refining processes depend upon the oxidation of a highly carburized iron which invariably results in contaminating the steel with oxygen. The oxygen .thus introduced presents many problems to the refiner, who in turn has attempted to rid the steel of this impurity by deoxidation with elements such as manganese, silicon and aluminum. The importance of the limiting concentrations of carbon and oxygen is accentuated in view of a number of recent researches which have indicated in many instances the existence of relations between oxide inclusions and dissolved oxygen and physical properties and chemical behavior of steel. The determination of the equilibrium concentrations of carbon and oxygen existing in iron under steelmaking conditions is obviously of fundamental importance. It has been generally assumed that the product of the equilibrium concentrations of carbon and oxygen in liquid iron is a constant and that this product is directly proportional to the carbon monoxide pressure in equilibrium with the liquid iron. Herty1,2 has computed values for this product based on open-hearth data which are all in the neighborhood of 0.01 to 0.03 (per cent. FeO X per cent. C) for temperatures in the vicinity of 1550° to 1600 C. and one atmosphere pressure. Kinzel and Egan3 have attempted to determine the value of this product by exposing liquid iron to carbon monoxide at one atmosphere pressure. The value reported by them was 0.0005 at 1550°. C. In. order to apply certain equations to the rate of carbon elimination in the open-hearth process, Feild4 found it necessary to assume. a value of 0.0102 at 1580° C. for this

Jan 1, 1931

Adams, Bernard, Student, South Dakota School of Mines. Rapid City, S. D. &apos;30 Ahlskog, Harold A., Student, Washington State College Pullman, Wash. &apos;30 Aldridge, John, Student, New Mexico School of Mines Socorro, N M. &apos;30 Almstrom, Adne A., Student, Met. Engrg., Washington State College Pullman, Wash. &apos;29 Ancell, Virgil F., Student, Missouri School of Mines Rolla, Mo. &apos;30 Ankudinoff, N., Mill Draftsman, Arthur G McKee & (:o., 2422 Euclid Ave., Cleveland, Ohio. &apos;30 Apablasa, Salvador C., Student, Univ. of California Los Angeles, Cal. &apos;31 Armstrong, Robert H., Student, Lafayette College Easton, Pa. &apos;31 Armstrong, Thomas E., Student, Univ. of California Los Angeles, Cal &apos;31 Aud, Robert A., Student, Lafayette College Easton, Pa. &apos;30 Backus, Robert Small, Student, Mass.- Inst. of Tech . Cambridge, Mass. &apos;30 Bailey, William C., Student, Univ. of California Los Angeles, Cal &apos;30 Banning, Lloyd H., Student, South Dakota State School of Mines Rapid City, S D. &apos;81 Barclay, M. G., Student, Colorado School of Mines Golden, Colo. &apos;30 Barger, Thomas, Student, Univ. of North Dakota Grand Forks, N. D. &apos;29 Barker, C. L., Student, Colorado School of Mines Golden, Colo. &apos;30 Barker, Edgar Morgan. Student, Univ. of Utah Salt Lake City, Utah. &apos;31 Barnwell, Earl E., Student, Oregon State College. Corvallis, Ore. &apos;30 Bartholomees, Geo. C Box 304, Bonne Terre, Mo. &apos;29 Bartholomees, Louis P., Student, Colorado School of Mines Golden, Colo. &apos;30 Bary, Robert L., Student, Univ. of Kansas Lawrence, Kans. &apos;30 Basham, Lester G., Student, South Dakota School of Mines Rapid City, S D. &apos;31 Bates, Walter H., Student, School of Mines, Univ. of Utah .. Salt Lake City, Utah. &apos;30 Beardshear, George T., Student, South Dakota State School of Mines.Rapid City, S D. &apos;31

Jan 1, 1923

By S. Feuerstein, L. Rice

The effect of low pressures on the flow and fracture behavior of molybdenum is described. For poly crystalline samples, room-temperature tensile tests indicate greater ductility under 10 Torr than under intermediate pressures up to and including atmospheric pressure (760 Torr). In addition, tests conducted at 760 Torr under atmospheres of air, dry nitrogen, and purified argon exhibited no apparent difference in mechanical properties. Critical tests involving baking in situ as well as those involving single-crystal deformation further imply that the ductility effect is a pressure-dependent phenomenon related only to the fracture process. This dependency is discussed in terms of adsorption and diffusion contributions. THE effect of very low pressures on material properties has heretofore been presumed to be important only for substances possessing relatively high vapor pressures at ambient temperatures. Research has therefore been concentrated primarily on organic solids and liquids, and in some instances on metals such as zinc and cadmium. Most vacuum-effect studies&apos; on the mechanical behavior of metals have been performed under conditions of either cyclic loading or creep rupture at elevated temperatures, i.e., over extended time periods. These studies were not restricted to high vapor pressure materials but also encompassed such metals as gold, copper, and nickel. Very little concern, however, was placed upon the importance of a vacuum environment on the mechanical behavior of metals subjected to a simple unidirectional deformation at ambient temperatures. A tension test is generally of short duration as compared to a creep test, and at room temperature vacuum effects if any would be expected to be surface-limited. In early 1963, Kramer and podlaseck2 reported a change in the bulk flow behavior of aluminum single crystals during room-temperature tension tests. The deformations were performed under pressure conditions of 760 to 3.4 X 10-8 Torr and indicated for the first time a vacuum surface effect contributing to the bulk tensile behavior of metal specimens. As a consequence, an experimental program was initiated in this Laboratory to study the effects of ultrahigh-vacuum conditions on the mechanical behavior of metals. The results of a preliminary study on poly-crystalline molybdenum3 revealed, unlike Kramer&apos;s observations of changes in the stress-strain behavior, only an increased ductility under ultrahigh vacuum. Flow behaviors were nearly identical for all tests re- gardless of pressure. This paper presents comprehensive results obtained in this area of research. 1) EXPERIMENTAL PROCEDURE Three material categories were used in this study: sintered and are-cast polycrystalline molybdenum of nominal purity 99.93+ pct and single-pass electron-beam zone-refined molybdenum single crystals having a nominal purity level of 99.99+ pct. The interstitial levels (weight percent) as determined by the Materials Testing Laboratories, Division of Magnaflux Corp., were as follows: sintered molybdenum (C— 0.005, H—0.0004, O—0.015, N—0.008); and arc-cast molybdenum (C-0.0038, H-0.0003, O-0.015, N-0.023). Single-crystal molybdenum obtained from Materials Research Corp. had a typical interstitial analysis of C-0.0015, H-0.00007, O—0.00045, and N-0.0001. Tensile specimens having a 5 mm diam by 50.8 mm length were prepared from these materials. An average grain diameter of 0.059 mm was obtained for the sintered specimens following a 4-hr, 1600°C heat treatment. Grain sizes from 0.019 to 0.149 mm were obtained in the arc-cast specimens following heat treatments from 1100° to 1600°C for 1 hr. This series of specimens was used exclusively for the grain-size effect studies. All samples were electrolytically polished in 97 pct sulfuric acid solution prior to testing. Experiments were performed at room temperature in an ion-pumped ultrahigh-vacuum system positioned in an Instron tensile machine, Fig. 1. A constant strain rate of 4.2 x 10-4 sec-1 as derived from crosshead displacement was assumed for the deformations. Starting vacuums ranged from 2 to 0.5 X 10-10 Torr. These pressure measurements were made using corrected values4 of an NRC Redhead gage. Comparative readings were also made against a G.E. triggered dis-

Jan 1, 1967

By G. Venturello, C. Antonione, G. Della Gatta

Results from work on the effect of inferstitials on recovery and recrystallization of&apos; very pure iron (99.995 pet) doped with nilrogen up to 400 ppm are reported. Nitrided specimens were obtained by heating the iron in a static atmosphere of NH3 + H2. The samples were cold-rolled 80 pet, subjected to a series of isochronal and isothermal anneals, and submitted to examination by X-rays, micrographs, and hardness tests. Small additions of nitrogen show a strong effect in reducing recovery of&apos; the mechanical properties of high-purity iron. At the temperatures of. the experiments, this effect proved greater than in the case of carbon. At 400°C pure iron recovers more than 50 pet of the total hardness increase, carburized iron vecovers 25 pet, and nitrided iron only 10 pet. On the other hand. the addition of nitrogen has, similarly to carbon, a very small effect on recrystallization; the effect is, however, slightly higher than that of carbon. When the concentration Of nitrogen is above the solubility limit in a iron at the temperattue of the experiments, an increase in the frequency of nu -cleation is also observed. THE object of the present work is to improve knowledge on the effect of interstitials both on recovery and on primary recrystallization of pure iron. In fact. at present there are no available data on the effect of nitrogen on high-purity iron. The only work which at present can be somewhat related to this problem is a work of Leak et al.1 in which grain boundary internal friction at high temperature in the presence of increasing amounts of nitrogen is studied by a torsion pendulum. The present work is a continuation of a previous one2 on the effects of carbon. EXPERIMENTAL PART Preparation of the Material. Pure iron was prepared following the same methods used in the pre- vious work2 and was nitrided using controlled quantities of ammonia in an apparatus similar to that used for carburizing. The apparatus consists essentially of a gas-tight quartz tube containing the specimens. The tube, maintained at constant pressure by means of a mercury seal, is placed in a resistance furnace. For nitriding, the NH3 + H2 atmosphere with a suitable concentration of NH3 was introduced into the tube, which had been previously carefully evacuated and degassed by heating at 600°C. The hydrogen used was carefully purified by passing it through a palladium filter. The ammonia required was prepared with the following reaction: CaO + 2NH4CI —CaCl2 + H2O + 2NH3 by heating the mixture of CaO and NH4C1 in a glass flask and then collecting the ammonia in a graduated Hempel burette. For each nitriding program a given amount of NH3 prepared by this method was introduced together with the H2 into the tube previously evacuated. Nitriding of the sample was then performed at 570°C for 48 hr. After this, to ensure a homogeneous distribution of nitrogen, the samples were further heated for 72 hr at 800°C. With this method which uses a static nitriding atmosphere, carefully controlled conditions of purity are obtained. Contrarily, with the conventional continuous-flow methods, using large quantities of circulating gas, there is a greater risk of introducing impurities into the samples. Furthermore, the required nitrogen concentration in the specimen is easily predetermined and obtained. A plot of the relation observed between the initial concentration of NH3 in the gas and the quantity of nitrogen introduced into the iron samples is given in Fig. 1. The data refer to samples of 1.2-mm thickness and to the nitriding conditions previously described. Furthermore, as a comparison, the data relative to two 0.5-mm-thick samples are reported. The presence of a reservoir in the cold zone of the reaction bulb made possible the gradual dissociation of ammonia on the sample in the hot zone. Internal-friction methods were used to determine the content of nitrogen dissolved in the iron samples. Some analyses were also carried out with chemical methods. The following table, Table I, shows a comparison of data obtained with chemical and internal-friction methods. The correspondence between chemical methods and internal-friction

Jan 1, 1964

By Richard P. Rothwell

THOUGH coal has been mined in this country for more than a century, no systematic effort was ever successfully made to ascertain the total amount produced. The production of the Cumberland Basin, Md., and the shipments from the anthracite fields of Pennsylvania, have been placed upon record, thanks to the intelligence sand foresight of Mr. C. Slack in the former case, and to the late Mr. B. Bannan in the latter. For some of the years between 1822 and 1842, the production of the Richmond Basin was reported by Mr. R. C. Taylor, but since that date till the author undertook this work it was impossible to obtain any statement of the production of this field. A few of the newer fields, such as that of Mt. Diablo, Cal., have been fully reported, and a few of the newer States have also had this service performed by some intelligent private individuals.; but no statistics of coal production have ever been collected either by the State or General Government, if we except the returns for the years 1869-70 of the census report. During the year 1875, by great exertions, I succeeded in obtaining, and July 3d, 1875, gave in the Engineering and Mining Journal what, "though not an accurate statement of our coal production," was " by far the most full and reliable that had ever been published." Though that report showed the production of bituminous coal to be 23,630,094 gross tons, or about six million tons more than had ever before been reported, it was in reality two and a half million tons below the actual output. The more full returns I obtained for 1875 gave many figures for 1874

Jan 1, 1877

K. Baumgarten has returned from active service in France. He reports that he saw C. W. Campbell, formerly with the 2d Engineers on the Chateau Thierry front, and believes that the latter returned to the United States on August 1. He also saw J. J. Croston; G. J. Sielaff, recently transferred to the Gas Service; Thomas M. Smither, survivor of the Tuscania after a 10-mile swim to Ireland. While in Paris he en-deavored to see Prof. Sauveur, but was unsuccessful. F. K. Borrow was given a commission as Lieutenant in the Royal Garrison Artillery in 1914, but had to relinquish it, on account of ill health, in August, 1915. His health has much improved and he hopes to resume active work toward the end of this year. Davis, A. W:, see British Columbia Engineers, below. Alfred Fox, Jr., enlisted in the Public Schools Brigade, Royal Fusiliers, in September, 1914; was gazetted Lieutenant in the Royal Field Artillery in December, 1914, promoted to Captain in November, 1915, and Adjutant to 78th Brigade, Royal Field Artillery, in January, 1916. He was appointed Staff Captain of the 12th Divisional Artillery in November, 1917. He has served continuously in France since July 1, 1915. He was awarded the Military Cross in January, 1917, and four times mentioned in despatches. E. Fraser-Campbell writes that he joined the London University 0. T. C. in January, 1918, for five weeks; enlisted with the Argyll and Sutherland Highlanders in February, 1918, and attended a training course for officer cadets at Chatham for six weeks. He was commissioned 2d Lieutenant, Royal Engineers, in April, 1918. After two months on home training at Chatham, he landed in France on June 23, 1918, posted to 180th Tunnelling Co., R. E., and is now with his unit up on the line.

Jan 10, 1918

By P. E. Demmler

The apparatus in which the process of bright annealing of copper wire was carried out consisted of a section of iron pipe, 6 ft. long and 3 ft. in diameter. The pipe was provided with flanges to which were bolted the end plates for sealing, also with inlet and outlet tubes to allow for the displacement of the air in the pipe by natural gas. After charging with copper wire, sealing and displacing the air, the pipe was heated to 350&apos; C. (662" F.). It was expected that the natural gas would furnish a neutral atmosphere which would prevent oxidation and give a satisfactory bright-annealed product. It was found, however, that the outer layers of wire were discolored and not suited for the use for which they were mtended. To obtain an idea of what was taking place in the annealing furnace, skeins of the hard-drawn wire were placed in a glass tube so that all changes in appearance could be observed as they were heated to different temperatures and under varying conditions. The temperature in each case was determined by means of a thermocouple placed in the tube close to the wire. Following is a summary of the results of these experiments: 1. When the wire was heated for 1 hr. in a current of natural gas at a temperature of 350") 400") or 500" C. (662", 752", or 932" F., respectively), there was a marked darkening of the wire throughout the skein. 2. When heated for 1 hr. in natural gas at a temperature of 600" C. (1112&apos; F.), there was no coloration, the wire remaining clean and bright. 3. When heated in natural gas to 350" C. until darkened and the treatment continued with the temperature raised to 600&apos; C., the coloration disappeared and the wire became clean and bright.

Jan 1, 1923