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By W. T. Burns

Attempts were made in 1908, at the Great Falls Works, to produce ingots direct from the Butte precipitate by smelting the material in a reverberatory refining furnace. The ingots produced in this manner averaged 99.4 per cent. of copper and 0.40 per cent. of arsenic and antimony. The copper content being considered too low, it was decided to cast the copper into anodes and to treat the anodes in the electrolytic plant. No. 1 Furnace, in which the precipitate was treated, was a regular cathode refining furnace previously employed in making wire bar, cake, and ingot from electrolytic cathodes. The hearth of the furnace was 24 by 12 ft., having a capacity of 100,000 lb. of cathodes. The furnace was coal fired, and the copper was dipped by means of trolley ladles. The average composition of the furnace charges was as follows: Per Cent. Peer Cent. Copper. Precipitate,..........7.5.3 40 to 80 Purification cathodes,.....1.9 92 Refinery slag (oxide slag),.. 10.1 50 to 60 Electrolytic cathodes,... 2.1 99.9 Precipitate anode scrap,.... 3.1 99.0 Scrap copper,.........7.5 99.2 100.0 The slag from this furnace amounted to 46 per cent. of the total amount charged and was of the following average composition: Per Cent. Cu..............16.86 SiO2.............34.7 FeO.............18.8 A12O3.............13.0 CaO.............9.4 MgO.............2.7 S............... 0.47 As..............0.11 Sb...............0.006 Ag, oz per ton.....0.18

Jan 1, 1914

By T. K. Perkins, O. C. Johnston

Because of the influence of dispersion on miscible-displacement processes, diffusion and dispersion phenomena in parous rocks are of current interest in the oil industry. This paper reviews and summarizes a great deal of pertinent information from the literature. Porous media (both unconsolidated packs and consolidated rocks) can be visualized as a network of flow chambers, having random size and flow conductivity, connected together by openings of smaller size. In such a porous medium, the apparent diffusion coefficient D is less than the molecular diffusion coefficient Do, as measured in the absence of a porous medium. For packs of unconsolidated granular material the ratio D/D, is about 0.6 to 0.7. For all porous rocks, both cemented and unconsolidated, the ratio of diffusion coefficients can also be represented as D/Do = 1/FF where F is the for- mation electrical resistivity' factor and 4 is the porosity. If fluids are flowing through the porous medium, dispersion may be greater than that due to diffusion alone. At moderate flow rates the porous medium will create a slightly asymmetrical mix zone (trailing edge stretched out), with the longitudinal dispersion coefficient approximately proportional to the first power of average fluid velocity (if composition is nearly equalized in pore spaces by diffusion). If the velocity in interstices is large enough, there will be insufficient time for diffusion to equalize concentration within pore spaces. In this region, longitudinal dispersion increases more rapidly than fluid velocity. At low velocities in interstices, transverse dispersion is characterized by a region in which transverse diffusion dominates. If the fluid velocity gets high enough, there will be a transition into a region where there is stream splitting with mass transfer but with insufficient residence time to completely damp-out concentration variations within pore spaces. There are several variables that must be con- trolled to get consistent longitudinal and transverse dispersion results, viz., (1) edge effect in packed tubes, (2) particle size distribution, (3) particle shape, (4) packing or permeability heterogeneities, (5) viscosity ratios, (6) gravity forces, (7) amount of turbulence, and (8) effect of an immobile phase. INTRODUCTION Diffusion and dispersion in porous rocks are of current interest to the oil industry. This interest arises because of the influence of dispersion on miscible-displacement processes. In a recovery process utilizing a zone of miscible fluid, there is the possibility of losing miscibility by dissipating the miscible fluid or by channeling or "fingering" through the miscible zone. Diffusion and dispersion are two of the mechanisms that may lead to mixing and dissipation of the slug. On the other hand, dispersion may tend to damp-out viscous fingers which may be channeling through the miscible slug. 58 Hence, dispersion may be detrimental or beneficial (if it prevents fingering through the miscible zone). Therefore, it is doubly important that we understand these processes. In this paper we review, summarize and interpret a great deal of information from the literature. In particular, we will briefly discuss molecular diffusion in miscible fluids. Then we will discuss what differences to expect for diffusion in a porous rock. If there is movement of the fluid through the rock, then there may be an additional mixing or "dispersion". Furthermore, the dispersion longitudinally (in the direction of gross fluid movement) and transverse to the direction of fluid movement will not be equal. We will discuss both types of dispersion as well as several variables which can affect dispersion (viscosity differences, density differences, turbulence, heterogeneity of media, etc.). This group of variables has sometimes led to difficulty when comparing literature data. DIFFUSION OF MISCIBLE FLUIDS If two miscible fluids are in contact, with an initially sharp interface, they will slowly diffuse into one another. As time passes, the sharp interface between the two fluids will become a diffuse

By E. T. Turkdogan, L. S. Darken

Using the quadratic formalism, thermodynamic equations are derived for the composition dependence of the heat and entropy of mixing. The applicability of these equations is confirmed by available experimental data on the activities and heats of mixing for binary metallic systems of Group ZZB elements. In a recent paper arkeen' introduced a quadratic formalism describing the composition dependence of the activity coefficient in the terminal regions of binary metallic solutions. That is, in the terminal region, which may extend to as much as 60 at. pct, the logarithm of the activity coefficient, log y,, of component 2 is a linear function of (1 - N,)' where N2 is the atom fraction of component 2. Similarly, for the other component, log yl is a linear function of (1 - N,)'. A number of iron-base binary liquid alloys were shown to obey this quadratic formalism. arkeen' extended this formalism also to any corner of a ternary system and showed that the activity coefficients of the components 1, 2 and 3 (1 is taken as the solvent) can be represented by quadratic terms involving five parameters, four of the binaries and one for the ternary system. Numerous examples given by arkeen' demonstrated the general applicability of the quadratic formalism to iron-base systems over a wide composition range. In this paper further examples are given of binary liquid systems (Group IIB elements, Zn, Cd, and Hg) and of several solid solutions, again demonstrating the appropriateness of this concept. A further purpose of this paper is to extend the quadratic formalism to the enthalpy and excess entropy of binary metallic solutions and to test the equations so found using available experimental data. QUADRATIC FORMALISM FOR HEATS AND ENTROPIES OF MIXING OF BINARY METALLIC SOLUTIONS The following equations, reproduced from Darken's paper, are for the two terminal regions of binary systems. at infinite dilution and a's are temperature dependent parameters to be determined from the experimental data. Although the quadratic formalism is an assumed representation of the data, Eqs. [I] to [4] are thermo-dynamically consistent with the Gibbs-Duhem relation and satisfy Raoult's and Henry's laws as limiting cases. As pointed out previously,' the following form of the Gibbs-Duhem equation facilitates the integration in general but particularly in regions I and 11, where each of the derivatives is constant. The partial molar enthalpy of solution i, (and i; the value of i, at infinite dilution) are related to the activity coefficients y, and y," by the thermodynamic relation Differentiating Eq. [l ] with respect to 1/T and substituting the above thermodynamic relation gives for region (I) It is reasonable to assume that over a temperature range of experimental interest, the enthalpy of mixing is essentially independent of temperature, implying from Eq. [7] that the derivative da,,/d(l/) is also independent of temperature. On the basis of this argument, the temperature dependence of a has the form where £ and S have the units of enthalpy and entropy respectively; they are characteristic parameters for a terminal region of a binary system, e.g. for region (I), C12, S12 and for region (II), d:,,, S2,. Using this equation gives for dff ,/ d(l/), From Eqs. [7] and [9] an expre_ssion is obtained for the composition dependence of L,. Similar calculations are made for El and the results are summarized below for the two terminal regions. For region (I), The corresponding expressions for the molar heat of solution, AHM, are readily obtained from the above equations for the two terminal regions: For region (I),

Jan 1, 1969

By David P. Shoemaker, Clara B. Shoemaker

It has been shown for an important class of complex transition intermetallic compounds (a, P, R, 6, and p phases) characterized by "normal" coordination [CN12 (icosahedral), CN14, CN15, CN16/ that interatomic distances nay be calculated to a good approximation as the sum of characteristic atomic radii. Two radii, one for major ligands and one for minor ligmds, are specified for each atom, except in the case of CN12 where only a miaaor-ligand radius is specified. The same appears to be true of transition-metal phases of simpler struc-ture: Laves phases (CN12, CN16), and p-tungsten phases (CN12, CN14). In the case of known examples of the more complex phases, a simple rule is given which specifies these radii. However, only a fraction of the known examples of the simpler phases obey this rule closely. To include the latter phases the rule may be modified by considering the radii as linear functions of the weighted average of the Pauling CN12 radii of the two kinds of atonzs, with the radii weighted according to the over-all chemical composition of the alloy. With very few exceptions interatomic distances for both tlze complex and the simpler transition phases can b$ predicted with this modified rule to within 0.06A. ManY intermetallic compounds are known of composition A,By, in which A is a transition element to the left of the manganese column in the periodic table and B is a transition element in or to the right of it. Frequently the coordination numbers (CN) found in these compounds are CN12 (icosahedral), CN14, CN15, and CN16 (called "normal" coordinations by Frank and Kasperl). Well-known examples are the cubic and hexagonal Laves phases which have CN12 and CN16, and the 0-tungsten (CrsO) phases which have CN12 and CN14. In the more complicated (often ternary) phases, such as the a phase,2 the Beck phases p3 and R~, the 6 phase,5 and the p p atoms occur with CN12, CN14, CN15, and (except for a) CN16; in many cases several crystallographically independent atoms of one particular CN occur in the asymmetric unit. A large number of independent interatomic distances are found in these complicated phases, varying from 20 in the a phase to 94 in the 6 phase. These distances show a large spread; they vary, for example, from 2.358 to 3.278A in the 6 phase. In our analysis of these distances we found that in each of these compounds every atomic position can be characterized by either one or two radii. The CN12 positions are characterized by a single radius, The higher coordinated positions are characterized by two radii, namely: the CN14 positions by 4 in the direction of the twelve "5-coordinated" ligands3 (called 'minor" by Frank and Kasperl) and by r:, in the direction of the two "6-coordi-nated" ligands (called "major" by Frank and Kasper); the CN15 positions by r15 for the twelve minor and r:, for the three major ligands; the CN16 positions by rlE for the twelve minor and r:, for the four major ligands. We have expressed the experimentally determined interatomic distances in observational equations as the sums of the appropriate pairs of these characteristic radii and the value of these radii have been determined by the method of least Squares. Despite their wide range, the interatomic distances could then be predicted by the sums of these atomic radii with an average deviation in any one compound of 0.06A or less. The results are summarized in Table I. Inspection of the radii thus obtained shows that in the structures in Table I the radii (in A) are given to a first approximation by the simple relationship: Where CN is the coordination number (12, 14, 15, or 16), and A = 1 for major ligands and = 0 for minor ligands. The interaLomic distances can be predicted within about 0.1A by sums of these atomic radii. Another phase belonging in this group with CN12, 14, 15, and 16 is the y phase & B7, in which A is molybdenum or tungsten and B is iron or cobalt. Recently the M%C phase has been refinedE and the observed distances also agree well with those calculated with Eq. [I]. (In the original determination of the structure of W6FeV7 the F$(II)-W(II1) distance was erroneously given as 2.84A, but we have recalculated it fro? the published parameters and found it to b? 2.57i4, in good agreement with the value of 2.6A predicted with Eq. [I.].) Many binary transition alloys are known to crystallize with the simpler structures having "nor-

Jan 1, 1964

By E. G. Dahlgren, Dan O. Howard

THE West Edmond oil field, which covers parts of Oklahoma, Canadian, Kingfisher, and Logan Counties in the State of Oklahoma, is in geographical extent the largest single oil field found in the state. At the present time, its area of 26,800 acres is almost twice as large as the Oklahoma City field, which hitherto was the state's largest field. Many authorities believe that the West Edmond field is the most important oil pool found in the United States since Pearl Harbor. The discovery of the field without the help of geological, geophysical, or other recognized technical information, the fact that the oil and gas accumulated in a stratigraphic or wedge-type trap, and the rapid development of the productive area under wartime conditions are some of the interesting features of the field. The West Edmond field lies west of the Oklahoma City, Britton, and Edmond fields. The field is in an area that has been considered on the west flank of the Granite Ridge line of folding, on which a number of Central Oklahoma's most important oil fields are located. Over a period of years, especially since the discovery of the new pools such as Oklahoma City, Edmond, Britton, and Crescent, the general area of the West Edmond field has been explored intensively by geological and geophysical methods. This led at times to the drilling of a few dry Wilcox sand tests.

Jan 1, 1945

By Donald F. Kennedy

During the past several years Climax Molybdenum Co. has been engaged in testing various types and sizes of hollow drill steel. The majority of tests have been on 7/8-in. hexagon st.ee1, inasmuch as it represents approximately 70% of total drill steel consumption at the Climax operation. Prior to December 1960, tests on 7/8-in. hexagon drill steel were conducted on steel with a forged collar and, in most cases, with a threaded bit connection. Through these tests and research, some improvement in steel life was achieved by making changes in heat treatment, design and alloying constituents. However, during that month, research and testing commenced on a rubber collar which was designed to replace the forged collar on 7/8-in. hexagon drill steel. Manufactured by the LeRoi Div. of Westinghouse Air Brake Co.. the collar. is very simple in design, consisting of a 1 ½ -in. diam steel cylindrical sleeve 2 in. long, containing a bonded rubber insert and attached to the steel with an epoxy cement

Jan 8, 1962

By J. Blodget Britton

To the question, " Do the Pennsylvania anthracites contain phosphorus?" asked at the last meeting of the Institute during the discussion on the metallurgical value of Western lignites, I can now give a definite answer. Through the kindness of a gentleman connected with the Philadelphia and Reading Railroad, and another connected with one of the principal ironworks on the Lehigh, there was sent to the Ironmasters' Laboratory a number of samples of the coals now largely shipped from the Schuylkill and Lehigh regions. Seventeen of these I examined for their contents of ash and phosphorus, and obtained results as follows : Ash. Phosphorus. No. 1, . 4.10 .0063 2, . . . . 7.97 .0209 113, . 5.53 .0049 114, . . . . . . . 6.55 .0056 . 5, . 5.39 .0761 . . . . . . . 11 6, 14.15 .0593 7, . 10 43 ,0049 rl 8, . . . . . . . 5.29 .0354 9, . . . . . . . 3.01 .0042 6L10, . . . . . . 3.03 .0042 1 1 . 275 .0014 12, . 2.82 ,0111 l'13, . .3.69 trace L1 14, . . .2.35 trace 15, . . . . . . . 7.22 .0014 16, . . . . . . . 3.49 .0167 17, . 4.63 trace

By J. T. Norton, Pekka Rautala

The phases and equilibria in the W-Co-C system have been studied by X-ray diffraction methods, metallographic technique, and thermal analysis. In addition to the 7 phase, two double carbides, called 8 and have been revealed. The compositions correspond to CO3 W6C2 and Co3-W10C4. The reactions leading to these phases have been explained and tentative diagrams of stable and metastable equilibria proposed. The basic reactions in sintering cobalt cemented tungsten carbides are discussed. THE W-Co-C system is of fundamental importance in practical carbide manufacturing as well as for the understanding of the sintering mechanism. Surprisingly little is known about this system, for the probable reason that all the important alloys are of two-phase structure and that the diagram Co-WC has been treated as a quasi-binary. This obviously is incorrect, because WC decomposes before melting. One ternary phase, 7, of composition Co3W3C has long been known. It was first studied by Adelskold, Sundelin, and Westgren,1 although the isomorphous iron-tungsten carbide was known earlier. There have been in the literature several reports of two 7 phases.' " Also the 7 phase has been considered unstable by Takeda4 and Westgren.1 The Co-WC diagram has been studied by Wyman and Kelley5 and a quasi-binary diagram has been published by Sandford and Trent.2 Takeda has published a tentative Co-W-C diagram, considering both metastable and stable equilibria. However, the lines of two-fold saturation are shown only partially and it seems impossible to complete the diagram without violating the phase theory. Therefore it seemed desirable to examine the system in more detail. Experimental Procedure The alloys used in the present investigation were made of powders of tungsten, tungsten monocarbide, cobalt, and carbon and were of the grade used in manufacture of commercial cemented carbides. The powders were ground and mixed in small stainless steel ball mills, using balls of the same material. Benzene was used as a dispersing agent. The mixing period was 1 hr, since this was shown to give suffi- ciently good mixing of the powders without too great a contamination from the mill. After ball milling, the specimens were pressed in cylindrical or rectangular dies. No paraffin or other lubricant was used and the small compacts had sufficient green strength to be handled without difficulty. Several sintering furnaces were employed. The most satisfactory arrangement was a vacuum furnace based on the Arsem principle which employed a graphite helix as the resistance heating element. Specimens were placed on graphite stands and there was generally a slight carburization or decarburiza-tion of the specimen surface, depending on the carbon content of the alloy. The evaporation of the cobalt at a sintering temperature of 1400°C was not significant, but became severe at 1500°C and higher. The sintering time was 1 hr at 2000°C and 2 to 4 hr at lower temperatures. It was not possible to quench the specimens, but the cooling rates were rather fast, greater than 300°C in the first minute. In the system under investigation, the reactions are sluggish, and it is believed that the high temperature structures are satisfactorily retained. The principal method of investigating the sintered specimens was X-ray diffraction by the Norelco recording spectrometer. Approximate determinations of the phase boundaries were made by the disappearing phase method. Ternary Phases To study the phase formation in W-Co-C system, a series of specimens was sintered at 1400°C. In this experiment two ternary phases, called here ? and k were formed in addition to the well-known 7 phase. The 7 phase, which has been completely described by Westgren: showed a range of homogeneity from 7 to 20 pct C and from 38 to 48 pct Co. At 1400°C the 7 phase was found to be in equilibrium with monotungsten carbide, 8, tungsten, 8, #?, and liquid. The boundaries toward #? and liquid were difficult to determine and appeared to be very temperature sensitive. The other boundaries are believed to be well fixed. The homogeneity range of 7, as measured in this work, is considerably smaller than the one

Jan 1, 1953

By AIME AIME

A LUSTY baby of the Institute, the Coal Division, showed that it had acquired a full set of teeth and was capable of man's work at the Division meeting at Fairmont, W. Va., on March 26 and 27. At this second of a series of field meetings, the first of which was held in Pittsburgh last fall, the industry in the East was represented from top to bottom and good humor and enthusiasm were the predominant notes. West Virginians are always good hosts and this meeting would have proved the statement to any inclined to doubt it. The spacious auditorium of the Fairmont Hotel was arranged for the technical sessions, the hotel being headquarters for the meeting. About a hundred and twenty-five representatives were registered and in attendance when Thomas G. Fear, chairman, opened the morning session at 10 o'clock Mr. Fear first introduced Howard Eavenson, vice-chairman of the morning program, who, as chairman of the Coal Division, had labored long and cheerfully to make the meeting successful. Mr. Eavenson talked briefly on what the organization was doing, pointing out that these field meetings were designed to bring the members into closer touch with the parent Institute and give the younger engineers in the field a better opportunity to participate in the work the Institute is doing. He congratulated the various committees for their work in promoting the meeting.

Jan 1, 1931

By J. F. Breedis

The morphology and crystallography of marten -site formed during quenclzing were examined by transmission electron microscopy in alloys whose compositions lie between Fe-19 wt pct Cr-11 wt pet Ni and Fe-33 wt pet Ni. Depending upon composition, four types of transformation products were observed in this portion of the Fe-Cr-Ni system. Three of these products are denoted as lath, plate, and surface martensite. The hcp structure found in association with martensite it? certain higlz-clzromium stairzless steels does not influence the transformation crystallogyaphy and cannot he Considered to act as a transitional structure in the transformation from austenite to martensite. DISTINCT changes in the characteristics of mar-tensitic transformations are produced by the partial replacement of nickel by chromium in austenitic iron alloys. Large, discrete martensite plates form in Fe-30 pct Ni, while aggregates of small crystals form in sheets parallel with (111)A austenite planes in stainless steels containing in the vicinity of 18 pct Cr and 8 pct Ni. These transformation structures are termed plate and lath martensite, respectively. In addition, an hcp structure (E) has been observed in certain high-chromium stainless steels in association with martensite. It has been suggested that the E structure acts as an intermediate step in the nucleation of martensitel-' and influences the morphology and crystallography of the final transformation product. However, this structure may be the consequence of the deformation of austenite arising from the shape distortion accompanying the transformation to bcc martensite.' An hcp stacking of atoms is produced in an fcc lattice by the introduction of an intrinsic stacking fault on alternate (111)A planes. At present, the arguments behind each explanation for the E structure are based on circumstantial evidence. This investigation seeks to determine the importance of the hcp structure to the martensitic transformation, and to examine the crystallography and morphology of the structures produced in bulk samples by quenching in alloys whose compositions lie between Fe-19 wt pct Cr-11 wt pct Ni and Fe-33 wt pct Ni. These aspects of the martensitic transformations occurring in these alloys have been studied by electron metallography and selected-area diffraction of foils examined in transmission in the electron microscope. EXPERIMENTAL METHODS The alloys have been prepared from thoroughly mixed powders of pure iron (99.6+ pct, 0.06 max pct C, 0.15 max pct N), chromium (99.9+ pct), and nickel (99.9+ pct). After sintering in an Ar-H2 atmosphere, the mixtures were melted by induction heating in recrystallized alumina boats under purified argon. The ingots were cold-rolled to 0.4-mm sheets (100 pct reduction in thickness) after the removal of at least 1.5 mm from their surfaces by grinding. Three-millimeter discs were punched from the cold-rolled sheet and annealed at 1150°C for approximately 24 hr in evacuated quartz capsules. The average grain size was 40 µ Thin foils for examination in transmission in the electron microscope were prepared from discs quenched to liquid-nitrogen temperature. A depression was first jet-machined into the center of a disc and a thin area (less than approximately 3000A in thickness) was produced at the base of the depression by electropolishing. Electron-microscope studies utilized the RCA EMU-3 and the Philips EM-100B microscopes operating at 100 kv. X-ray examination of the polycrystalline alloys was performed either in a diffractometer or in a

Jan 1, 1964

By E. J. KENNEDY

THE annual dinner-dance was held in the large ball room of the Commodore hotel Wednesday evening. A total of 577 were seated at the dinner, over which President Eavenson presided as chairman and toastmaster. In introducing George C. Stone, the James Douglas Medalist, W. R. Ingalls outlined the former's association with the zinc industry. He said, in part In designing and building Palmerton, Stone erected a metallurgical monument and won the title of chief engineer of the New Jersey Zinc Co., with transferal to its New York office in 1900. There lie held forth in dignity, efficiency, and with appreciation until his retirement from active service in 1929. After a few years lie was diverted from the position of chief engineer for his company to the superior one of chief metallurgist and that gave to Stone his next big chance.... This was the conception of a research department and the ability to persuade his directors to adopt it. I shall not pretend to summarize the great things that afterward developed. I shall mention only the institution of the manufacture of lithopone in this country, the charging of the Wetherill furnace with briquets, the mechanicalization of the Wetherills, the accomplishment of continuous distilling, and most recently the introduction of reflux-refining.

Jan 1, 1935

By Edwin Ludlow

THE responses to the request of the Finance Committee have been coming in with gratifying results, .but there have also been about a dozen letters received objecting in various ways to the voluntary subscription. These can be summarized as: First.-That the dues should have been increased, and thus impose the same burden on everyone. This would not have met the present situation, as under the constitution no increase could be effective until 1922. Second.-The Institute should 'live within its means, and reduce its expenses to correspond with its income. As far -as possible this was done by deferring the publication of Volume LXIV until 1921, although the papers published in that volume, were presented at the meeting in February, 1920. It is to avoid being obliged to do this again that the subscription is asked, as we feel that it is, a duty we owe to our membership_ to give them the papers presented at as early a date as possible.. Our financial situation is due to the very large increase in the cost of publication; owing to the high price of paper and printing. The cost of paper is now decreasing, and we hope that there will be' wage adjustments that will permit a lower cost for printing. Under present conditions each volume of our TRANSACTIONS costs three times as much as it did in 1917 and we would be able to publish only one' volume per year. Third.-That there are too many papers published that are 'of no interest to the writer of them .complaint.-This is undoubtedly true, but it must be remembered that the membership of the Institute includes all branches of mining and metallurgy and that all these branches are entitled to be' represented in our TRANSACTIONS by papers.

Jan 1, 1921

By J. C. Bradley

THE relation of annealing temperature to conductivity of copper wire has been determined. Conductivity hard was 98.26 per cent. After a 10-min. heating at 200°C. it was 98.69. By annealing 10 min. at 300° C. a large increase, to 100.93, occurred. Maximum conductivity, 101.15, was attained after a 500° C. anneal; thereafter it decreased to 100.53 after a 950° C. anneal. If copper is gassed the decrease is much more than this. Materials and Methods The work was done on high grade electrolytic copper, 99.942 per cent. copper plus silver, silver 0.0008 per cent. It was hot-rolled to >/4 in., then cold drawn to 0.080 in. The wire was cut into 25 5-ft. lengths and numbered 1 to 25 as cut. Four samples were tested hard. The others were wound into 5-in. diameter coils. For the 100° C. heating a coil was put into water, the water brought to boiling, and the wire kept at this temperature for 10 min. For the higher temperatures the coils were placed in envelopes of sheet copper, a little water added, and the envelopes sealed by folding over the edges twice, and hammering them together. This kept the air out very well. The envelope and wire 'were brought to the desired temperature; this was maintained for 10 min., then the whole was water-quenched.

Jan 1, 1927

By Axel Sahlin

Jan 1, 1898

By J. F. Myers

A bit of old philosophy: The optimist, the pessimist, The difference is droll; The optimist, the doughnut sees, The pessimist, the hole. This is a neat summation of the viewpoint of those engaged in "treating the crude mineral crust of the earth." Many of those in high places have reminded us during the year of the diminishing supply of the resources so essen-

Jan 1, 1948

By Clyde E. Williams

IN planning a postwar program for manufactured products, it is essential that the bases for the plans be wisely chosen. First we must make certain assumptions as to the war's ending. Let us assume: (1) complete victory by the United Nations, (2) peace terms that will ensure the direction of the economy of all nations of the world toward peaceful pursuits, and (3) an early ending of the war, that is, before the nations of the world, excluding the enemy, are near the point of physical and spiritual exhaustion. Thus, our manufacturing plants and transportation facilities will still be in good shape. The plants and transportation facilities, as well as the cities of a large part of Europe, however, will be badly crippled. The rich mineral and other raw material resources of the world, little of which was under control. of the Axis powers before the war or will be after the war, will not be used up. Control of these raw materials, or at least an important part of them, will remain in the hands of the strong peaceful nations.

Jan 1, 1943

By Richard Akerman, Frederick Prime Jr

[THE attention now being paid both in this country and Europe the greatest economy in the working of the blast furnace, and the eagerness with which all thoughtful men in the iron business look for any new information which will tend to throw light on this subject, is a quite sufficient excuse for presenting this paper to the American Institute of Mining Engineers.] I. It must be borne in mind that when two bodies unite to form a chemical compound, heat is almost always evolved. In order to

By Richard Akerman

(Translated by FREDERICK PRIME, JR., Professor of Metallurgy in Lafayette College, Easton, Pa.) [THE attention now being paid both in this country and Europe to the greatest economy in the working of the blast furnace, and the eagerness with which all thoughtful men in the iron business look for any new information which will tend to throw light on this sub¬ject, is a quite sufficient excuse for presenting this paper to the Amer¬ican Institute of Mining Engineers.] I. It must be borne in mind that when two bodies unite to form a chemical compound, heat is almost always evolved. In order to

Jan 1, 1873

By P. G. Shewman, T. L. Wilson

Using published surface-diffusion (D,) data and published sintering equations, it is shouln that surface difusion should dominate the neck-growth stage of intering for all materials in which D, has been measured (six metals and A1as). Also, grain boundary diffusion can be expected to contribute appreciably to shrinkage and possibly to neck growth below some critical temperature of the order of 70 pct 01- the absolute melting temperatuve. In view of the widespread conclusion in previous sintering work that volume diffusion dowzinates neck gvowth, experiments were conducted using spherical copper powders to test this conclusion. Scaling studies on neck growth at 950°and 1020°C clearly demonstrated that suyface diffusion dorninates. Kinetic studies on shrinkage gave more equivocal results that indicated an increasing role of' grain boundary transport at lower temperatures. Five diarszeters from 100 to 300 u were used in the scaling sludy and a temperature range of -650' 10 950 C was covered in the shrinkage studies. All experiments were conducted in dvy hydrogen. In 1949, Kuczynski published his now classic paper on the determination of the transport mechanism in sintering from the time laws of neck growth. In the interim, these laws have been applied to many systems and slightly modified by several authors. Essentially all these authors concluded that, for crystal- line materials, the dominant transport mechanism in neck growth is volume diffusion. This stems from the observation that the neck radius increases about as t"5 and that the activation energy approximates that for lattice diffusion. A related but independent series of studies stems from Mullins' rigorous analysis of the growth of the groove formed where a grain boundary meets a free surface." xperimental work stemming from this analysis has shown that for each crystalline material studied (Au, Ag, Cu, Ni, Fe, Pt, Al2O3) surface diffusion was clearly the dominant transport mechanism for groove widths up to the order 10 to 20 p. The ratio of the quantity of material being carried by lattice diffusion to that carried by surface diffusion increases linearly with the groove width, so surface diffusion is dominant for all widths under 10 to 20 u. The analysis of the relative contributions of surface and volume diffusion to grain boundary grooving, and to neck growth in sintering, shows that they are quite similar. Thus, using the available surface-diffusion data and the approximate equations of Kuczynski, or the more rigorous recent equations of Nichols and Mullins, 3 it can be shown that the small necks between particles must grow almost entirely by surface diffusion. The purpose of this study was to re-examine the basis for the conclusion that the neck-growth stage of sintering proceeds by volume diffusion. Using spherical copper powders, of several different diameters, precise experimental measurements were made of both neck growth and shrinkage. Application of Herring's scaling laws to the neck-growth data clearly indicated that neck growth occurred by surface transport, even though the neck radius increased as or Using the recent analysis of Mullins and Nichols as well as published data on surface diffusion, it is shown that the observed time law, as well as actual rate of neck growth, can be satisfactorily explained by a surface-diffusion mechanism.

Jan 1, 1967

By Ben. B. Cox

The principal events during the year consisted in the exploitation of the Kirkuk field, the regular operation of the four-million-ton pipe line to the Mediterranean, and the discovery of low-gravity oil on three other structures in the West Tigris (Shergat) area. The Iraq Petroleum Co., Ltd. continued the systematic exploitation and exploration of its Kirkuk field, maintaining a carefully unitized operation. Bottom-hole pressure differentials and low gas-oil ratios were maintained. All crude was produced by flowing The cleaning up following the construction of the Mediterranean pipe line, which began deliveries in August, 1934, was completed during the first quarter of 1935. The line easily maintained its rated capacity for the remainder of the year. The Mosul Oilfields, Ltd., through its operating subsidiary, the B.O.D., Ltd., expanded its exploratory organization from 9 to 16 drilling rigs and discovercd 20" A.P.I. crude on the Sadid, Hibbarah and Qasab anticlines. Whether these discoveries will be commercial pools remains to be proved. The Qaiyarah-Najmah-Jawan field, which was discovered by the I.P.C. in 1928, was extended arid production was found in the Eo-Cretaceous as well as the "Main Limestone" (Eocene, Oligocene and Lower Miocene). Gas caps were found under each of the crests of the West Tigris structures. Negotiations are in progress between the Mosul Oilfields, Ltd. and the Iraq Government for the extension of the Anatolian Railway from the Turkish border to Mosul, with a view to tanking the heavy West Tigris crude to the Mediterranean. The subsidiary of the Anglo-Iranian Oil Co., Ltd.', the Khanaqin Oil Co., Ltd., continued to operate its Naft Khaneh field near the Iranian (Persian) border to supply the local Iraq market through the Rafidain Oil Co., Ltd. Somewhat more than 28 million barrels of crude was produced in Iraq during 1935. Crude delivcred to the pipe line for export during the years 1934 and 1935 was: Year BaRrels 1934................................................. 7,096,669 1935................................................. 27,014,904 Total as at Dec. 31, 193.5.............................. 34,111,573 ° Converted at an avcrage of 7.0 bbl. per ton.

Jan 1, 1936