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By J. D. Hanawalt, C. E. Nelson, J. A. Peloubet

The subject of the salt-water corrosion resistance of magnesium alloys is somewhat like that of the pitting of stainless steels, in that it involves a relatively small. percentage of the applications but receives a much greater proportion of the publicity. Actually magnesium alloys are in use in many exterior applications as well as interior, with no trouble from corrosion. Magnesium and its alloys have a striking stability against atmospheric attack, being far superior to iron. Specimens exposed unprotected to atmospheric weathering for Io Years show only a superficial surface-film formation. The basic nature of magnesium and of its important alloys is that they are also resistant to the attack of salt water even in an unprotected state, giving substantially no loss in weight after one year of alternate immersion in 3 per cent NaCl solution (Fig. 1). This basic behavior is often masked because of the extreme sensitivity of these alloys to certain impurities and combinations of impurities. It is known, and the subject of increasing emphasis, that higher purity leads generally to greater stability for many materials, non-metallic as well as metallic. However, a review of the literature on the corrosion factors in magnesium alloys shows that almost all researchers worked with base metal in which metallic impurities varied in uncontrolled amounts. The major factor, that of metallic impurities, Probably greatly overshadowed the effects of minor ones such as flux inclusions, nonmetallic impurities, porosity, metallographic state, which these researchers presumed to study. In the present investigation the first observation of interest is that whereas magnesium of commercial purity (99.9 per cent pure) has a corrosion rate in alternate immersion in 3 per cent NaCl solution at room temperature of anywhere from 5 to Ioo mg. per sq. cm. per day, the corrosion rate of high.purity magnesium is 0.15 ± 0.05 mg, per sq. cm. per day. The principle followed in the experiments was to add to such base magnesium other elements, singly and in inin in controlled and known amounts and to observe the corrosion behavior of the resulting alloy. These experiments show the existence of what may be called tolerance limits" of magnesium and some of its alloys for certain impurities. The extremely small percentages of impurities involved and the sharpness of the corrosion discontinuities appear to be quite unpredictable, In order to carry on this work, it was necessary to develop an analysis technique suitable to the problem. In some cases it was necessary quantitatively to analyze impurities to less than 0,001 per cent. The experimental data to be presented are based on observation of about 5000 alloy specimens and on more than 50,000 quantitative analyses. while the primary purpose of this paper is to present the experimentally obtained data on corrosion rates as a function of composition, and particularly to demon-

Jan 1, 1942

By J. L. Fitch, B. G. Hurd

The presence of gypsum in samples subjected to standard core analysis introduces serious errors in the measurement of water saturation and porosity. The magnitude of these errors, depending upon the type of analysis procedure used, has been evaluated experimentally and theoretically. Water-saturated pore volumes determined by vacuum distillation or retort procedures may be too high by as much as 48 per cent of the volume of gypsum present. The maximum error in this value determined by Dean-Stark extraction with toluene is 36 per cent of the gypsum volume. If pore space is measured by a Boyle's law type porosimeter the maximum erorr due to gypsum is 38 per cent of the original gypsum volume present. The conscientious core analyst may eliminate the errors caused by gypsum by either of two methods. He may apply suitable corrections for the water of crystallization removed from gypsum, or take special precautions to prevent dehydration of gypsum during core cleaning and alzalysis procedures. These alternatives are discussed and methods for obtaining reliable core analysis data are proposed. Gypsum (CaSO4 . 2H2O) occurs as a common mineral in many of the world's sedimentary basins. In addition to its presence as primary bedded evaporitic deposits, it is often found as secondary replacement zones and pore-fillings in host rocks. That it may cause false indications in porosity, both on neutron logs and in standard core analysis, has been generally recognized. False porosity interpretations from neutron logs result because the chemically bound water in gypsum attenuates neutrons as effectively as free water. Errors in core analysis result when gypsum is dehydrated prior to or during the analysis. Vacuum retort procedures used by many laboratories to determine fluid saturation and porosity effect a complete removal of water of crystallization from gypsum. The crystal water, distilled and collected with free water from the sample, is counted as water-sat11rated pore space. Dehydration of gypsum results in a decrease in volume occupied by calcium sulfate and a corresponding increase in pore volume. Thus, if gypsum is dehydrated by sample cleaning and drying procedures, subsequent porosity measurements with gas expansion or compression instruments will be high. The qualitative effect of gypsum on porosity determinations by retort procedures was discussed in a recent article by Bynum and Koepl3. They concluded that since false porosity was interpreted as being water saturated, determinations of oil content were not affected. Others in the industry, however, have pointed out that porosity values are often used with values of water saturation determined independently, e.g., from electric resistivity logs in making reserve estimates. Values of water saturation calculated from the formation resistivity using the Archie equation, S4= are actually low if values of are high due to gypsum. In this case, false porosity values due to gypsum could cause serious errors in calculations of oil-in-place. This investigation was made to determine quantitatively the effect of gypsum on porosity values determined by different core analysis procedures. EXPERIMENTAL PROCEDURES Dehydration of Gypsum The extent and rate of removal of water of crystallization from gypsum under conditions encountered in core analysis procedures were studied. Taken for the experiments were three types of relatively pure, naturally occurring gypsum, viz. selenite, satin spar and massive gypsum. Although all samples probably contained trace chemical impurities, each type lost the theoretical amount of water upon complete dehydration. An automatic recording thermobalance, similar to one described by Mauer2, was used to obtain dehydration rate data for samples heated in dry air. Water

By H. P. Stuwe

It is investigated whether a model of sphere packing permits the computation of the lattice parameters and their variation with concentration in various a phases; it does, except in phases containing silicon. Several observations indicate that a particular role is played by the "E-atoms" in the lattice. THE phase is formed by many alloys of the transition elements.'-' Its structure has been described by Bergman and Shoemaker,5,8 Dickins, Douglas, and Taylor,7 and Kasper, Decker, and elanger.' There are five kinds of crystallographically equivalent positions for the 30 atoms in the unit cell which have been designated by these authors I, 11, 111, IV, and V or, in the same sequence, A, B, C,D, and E, as shown in Fig, 1. For the purposes of the present paper two elements of the lattice will be discussed separately: The lattice planes perpendicular to the c-axis which are made up by the atoms A, B, C, and D and which determine the a-parameter; and the close-packed "vertical rows" of E-atoms which determine the c-parameter. asper,9 and Frank and kasper10 described the a phase and other complex structures as sphere packings. In these papers particular attention is paid to the coordination polyhedra. Lattice positions with an equal number of nearest neighbors are considered equivalent regardless of their crystallo-graphic description. This seems to work very well for the explanation of ordering phenomena in the a phase as far as information on this is available." If the description of the phase as a sphere packing is valid it should be possible to draw two further conclusions: 1) It should be possible to calculate the lattice parameters from the atomic radii of the components, and 2) It should be possible to predict the variation of the lattice parameters with concentration within one phase field. Both points are discussed in this paper. PROCEDURE Measurements of lattice constants were done with a symmetrical back-reflection X-ray camera. With Cr-radiation, about a dozen a1 lines could be observed with most samples. From the (550/710)- and 720-lines the a-value was computed. With this value the c-parameter was calculated from the (333)- and (413)-lines. Finally, the position of all the other lines was computed from the lattice parameters thus obtained. In this way the validity of the indexing could be checked and, at the same time, this proce- dure gave an estimate of the accuracy of the lattice parameters. A correction was made for film shrinkage. The atomic radii used in the computations are the Goldschmidt radii for coordination number 12. Actually, some of the atoms have a coordination number of 14 or 15, but the error thereby introduced is small. * For the computation of lattice constants from the atomic radii an "average atomic radius" of all components was used, i.e., complete disorder was assumed. Although this seems to be true for some systems like OS-Cr,4 it is not true in others.11,13,14 The ordering model, however, which has been suggested by Kasper on the basis of extensive research lets both kinds of atoms contribute to both the ''vertical rows" and the lattice planes perpendicular to them, so that even with ordering of this kind the assumption of complete disorder cannot introduce a very serious error in calculating lattice parameters. RESULTS Bergman and shoemaker6 gave a table of the interatomic distances in the Fe-Cr phase. If we disre-

Jan 1, 1960

By J. W. Pamplin

Some 40 miles east of Tampa is the center of the Florida pebble phosphate deposits. These are of Pliocene age and consist of several members of the Bone Valley formation.1 Physically the phosphate-bearing formation, locally called the "matrix," varies in thickness from nothing to about 25 ft., usually averages 10 ft., and consists mainly of clay, quartz and phosphate pebble, the latter particles varying in size from colloidal to one inch diameter. The pebbles range in color from dark gray, through white, to cream, and in hardness from that which must be broken with a hammer to that which can be scratched with the fingernail. They assay from 66 to 80 per cent bone phosphate of lime (called "B.P.L." in the trade) or tricalcium phosphate (Ca³P2O8) and are secondary apatites. They form from 15 to 50 per cent by weight of the matrix. Over the matrix lies a varying thickness (5 to 40 ft.) of overburden composed of quartz and clay. Briefly, mining consists of two operations2 in open pits about 200 ft. wide by 1/2 mile or more in length. In the first step overburden is removed by large electric draglines at the rate of about 700 cu. yd. per hour. This is followed closely by hydraulic mining of the matrix at the rate of about 300 cu. yd. per hour. This matrix yardage is moved from an improvised sump in the floor of the pit to an ore-dressing plant, sometimes a mile distant, by one, two or three "pit-cars" (pumping units) working on a 12-in. pipe line called the "rock line" to distinguish it from the high-pressure water line feeding the hydraulic giants, which is known as the "hydraulic line." This 700 yd. of overburden and 300 yd. of matrix—1000 yd. in all-amounts to about 1500 tons of material moved each hour. The overburden is dumped into the mined-out pit alongside the pit being mined. The matrix moves to the ore-dressing plant at the rate of about 7% long tons in 4000 gal. of water per minute—a ratio of approximately one to two by weight, or one to six by volume. This constitutes the "mill heads," but in the pebble district it is called the "matrix."

Jan 1, 1938

By Carl Pierce

THE writer of this article has not attempted to write a technical paper; on the contrary, he has tried to express in "steel-plant English," for steel men, a viewpoint drawn from his practice and experience. It is not his thought that it shall be taken as the "last word" in the making of this class of steel, or that good rimming steel cannot be made by any other practice. The paper was written to serve as the basis of a discussion from which it is hoped much benefit may be derived. The paper deals only with rimming steel made by the open-hearth process, and with the lower carbon steels, such as sheet and tin bar, rivet stock, skelp, etc., although good rimming steel as high as 40 to 50 carbon can be made by having good open slags and giving proper attention to working and tapping temperatures.

Jan 2, 1926

The Climax design is for the human being and his needs. Climax President Arthur Bunker has likened the high mountain operation to a giant, 250 million tons in weight, and 12 thousand feet high. No matter how huge or complicated the plant, the design must assure efficient operation by its human operators. By the same token, living and playing facilities must be designed for fullest satisfaction in use-else the capital investment is not justified. Even the product, molybdenum, finds its application through the ever growing demands of a highly industrialized society of humans. Research in Climax Laboratories, in tune with our technical age, helps guide molybdenum to its maximum use for society.

Aug 1, 1955

By Helmut Thielsch

MeTallographic specimens whose surfaces are to be investigated are too thick to allow either light or electrons to pass through them for microexamination by transmission. This difficulty is overcome with optical microscopes by illuminating the surface through the objective lens. For electron microscopes best results are obtained by preparing thin replicas of the surface of the specimen, placing them in the microscope and passing the electron beam through them. Since electron microscopes represent a rather recent invention, they have found little application as compared with optical microscopes. This is true because, aside from the cost of new equipment and development of new techniques, some of the older replica methods necessitated the destruction of the surface from which a thin transparent replica was obtained. In other processes in which the surface is preserved, either too tedious a procedure is required, unsuited to "mass-production" requirements of industrial laboratories, or replicas of insufficient contrast and sharpness are produced. In general, investigations with the electron microscope involve five steps: (I) polishing the surface of the metal specimen, (2) proper etching of the surface, (3) preparing the suitable replica from the surface, (4) examination and phorography in electron microscope and (5) interpretation. Preparation of Metal Surfaces Usual metallographic polishing is generclly satisfactory. It is important though that the final polish be applied very carefully, since otherwise evidence of a small amount of deformation might show up even on relatively deeply etched surfaces. A high-power microscope should be used to determine the suitability of the polish and etch. This, of course, is not different from optical examinations, but in these, if a deep etch is used, the problem is less serious. It is frequently difficult to detect with optical microscopes poor polishing aside fiom superficial scratches before etching. Figs. I and 2 show micrographs of "well" and "poorly" polished nickel etched by immersing the sample for 20 min. in a solution containing 8 grams cupric sulphate in 40 C.C. of concentrated HCl and 40 C.C. of Hz0 (Marble's reagent). The sample shown in Fig. I was polished in its final stages for 5 min. on a carborundum wheel followed by ro min. on a rouge wheel, whereas the sample shown in Fig. 2 was polished only I min. on the rouge wheel. Generally, this procedure does not guarantee that the surface of the specimen will be either undistorted or deformed. It was applied here merely to show the effects Of good and poor polishing. To the experienced investigator, plastic deformation is

Jan 1, 1946

By G. P. Boomsliter

IN previous discussions on stresses in hoisting ropes, little has "been said concerning the effect of the elasticity of the rope itself on the stresses due to acceleration. Laschinger1 has calculated acceleration stresses. for several cases but he has ignored the elasticity of the rope as a factor, except as it compresses the drum and stretches itself as it winds thereon. He also deals with steam plants and he shows the effect of the "jerky" start of the engine. This effect would actually be reduced by the elasticity of the cable. With the advent of the motor-driven hoist, new conditions have arisen. The jerk mentioned by Laschinger has been eliminated and smoother starting made possible. But the elastic properties of the rope seem to introduce considerable periodic acceleration stresses in the rope. The following discussion of acceleration stresses is based on the assumption of a constant acceleration at the drum. To be exact, the mathematical work is based upon the assumption that the top is moving upward with a constant acceleration, and ignores the fact that the cable is shortening as it winds. However, the effect of the shortening would be inconsiderable during the first part of the acceleration period. Most hoisting engineers make the assumption of constant acceleration at the drum. Under the older method of calculating acceleration stresses, this would be true with a constant torque motor. But if stresses vary, as this paper attempts to show that they do, constant torque would not give constant acceleration, although the velocity-time curves obtained in the full size test herein described showed that they approach rather closely to this condition, at least as nearly as could be measured.

Jan 2, 1927

By Robert D. Pike

IN November 1939, on behalf of the Harbison-Walker Refractories Co., the author undertook the study of the problem of utilizing the dolomite of northwestern Ohio for the manufacture of calcined magnesia suitable for use in refractories. Grateful acknowledgment is made of the unfailing assistance and encouragement throughout this work from the executive and technical staff of Harbison-Walker Refractories Company. The dolomite of the Niagara formation that is exposed or near the surface of a wide area in northwestern Ohio1 constitutes a vast supply of almost pure dolomite. It offers a virtually unlimited supply of cheap raw material of uniform dependable analysis for the manufacture of magnesia. A typical analysis of dolomite from the vicinity of Luckey, Ohio, follows: [ ] Brines containing magnesium chloride or sea water can be reacted with calcined dolomite to produce magnesia.2,3 In such reactions the MgCl2 of the brine supplies some of the magnesia and the amount of dolomite required is thereby reduced by an equivalent amount, but brines of commercial importance containing magnesium chloride are some distance away from the purest grades of the dolomite of northwestern Ohio. It was decided therefore to concentrate upon the development of a suitable process for separating the lime and magnesia of dolomite, depend¬ing upon the dolomite itself as the sole source of magnesia. This would make it possible to place a plant at the dolomite quarry, thus eliminating the cost of transporting the stone and also rendering the calcined magnesia available at a most convenient production point, considering the cost of delivery throughout the steel industry. The selection of a process depending solely upon the dolomite as a source of magnesia also necessarily entails production of the lime content of the dolomite as a by-product. It was recognized that if such a lime by-product could be produced in a suitable form, a plant location in northwestern Ohio would also be advantageous for marketing the lime. The problem, therefore, was the discovery and development of a low-cost process for separating the magnesia and lime of the dolomite of northwestern Ohio and producing each in a form relatively free from the other, and meeting the respective requirements of established markets. A satisfactory solution of this problem has been found, and it is the

Jan 1, 1947

By J. R. Jargon, H. K. van Poollen

Non-Newtonian fluids may be injected into a reservoir during secondary recovery operations. The non-Newtonian fluid used in this work is a power-law type of fluid that is, the viscosity of the fluid decreases as the flow rate or rate of shear increases. This paper presents equations for steady-state linear and radial flow of such fluids, transient behavior results from a finite difference model of a radial system, and transient behavior results from a field test. The equations that describe the flow of a non-Newtonian fluid are non-linear and are solved numerically. Finite difference solutions are presented as curves of dimensionless pressure drop at the wellbore us dimensionless time for a constant injection rate. Solutions were obtained for 5-percent, 10-percent and 100-percent PV of a non-Newtonian fluid for injection rates of 1, 10, 100 and 1000 cc/sec and for a 5 percent PV of non-Newtonian fluid located at T = Tw' 3, 10, 20, 50 and 100 ft for a flow rate of 1 cc/sec. The buildup curves do not exhibit a stmight-line portion as is the case for Newtonian flow through porous media. Correlations also are shown for the productivity index vs rate for the computer model study and the field tests. INTRODUCTION During various secondary recovery operations non-Newtonian fluids are injected. Such fluids, in general, include thickened water and gelled fluids. The term "non-Newtonian" implies that the viscosity is not only dependent upon temperature and pressure, but also on the rate of shear that is applied to the fluid. For example, water, which is a Newtonian fluid, will have essentially the same viscosity no matter what rate of shear is applied. A pseudo-plastic fluid exhibits a decreasing viscosity when higher rates of shear are applied; a dilated fluid has an increasing viscosity with increasing rates of shear. The objective of studies performed and described in this report is to obtain relationships and mathematical and empirical descriptions of the flow of non-Newtonian fluids through porous media. Simple mathematical relationships, computer studies that include the unsteady-state behavior of such fluids, and field tests are used. PREVIOUS LABORATORY STUDIES Laboratory studies have been performed by several investigators. The fluids used in one investigationl were surfactant-stabilized dispersions of water in hydrocarbons. Its Fig. 6 is reproduced as our Fig. 1. This effective-viscosity vs frontal-velocity diagram shows that this fluid is of the power-law type over a fairly large range of frontal velocities. Gogartyl developed an equation for the effective viscosity as a function of shear rate that reduces to Eq. 2 for frontal velocities greater than about 2 ft/D. The fluid characteristics used in the present study are similar to those reported by Gogarty. Christopher and Middleman2 performed experiments with power-law fluids flowing through pipes packed with glass beads. They used a modified Blake-Koteny

Jan 1, 1970

By Edwin R. Phelps

In the year 1900 about 212 million tons of bituminous coal were produced in the United States. Almost none of this was produced by surface mines (Fig. 1), because there was no large equipment suitable for stripping overburden at that time. By 1915 the surface mines had built up their capability largely through use of the steam shovel to the point that they produced 2.8 million tons of the nation's total production of 443 million tons. Over the intervening years between 1915 and 1970 surface mining provided a continually increasing percentage of the nation's bituminous coal, stimulated by the growing availability of giant surface mining machines, some of which are presently capable of removing 220 cu yd of earth with one bite of their mighty buckets. In 1970 the nation's surface mines produced 244 million tons of bituminous coal, over 40% of the total national production. On the other hand, the nation's underground mines hit a peak of 560 million tons in 1920, dropped to a low of 273 million tons in 1961, and are presently on a very slow rise. Environmental pressures generally oppose surface mining, and have forced coal companies to consider more underground mining in future planning. Also, since strippable reserves are decreasing in the eastern states, an increase in underground mining is expected over the coming years. However, in the western states there are enormous reserves to be extracted by surface methods. Why has surface mining increased, while underground mining has decreased? It's largely a matter of economics. The cost per ton is greatly reduced by surface mining because of the relative ease of obtaining the coal. Also, there is a much greater percentage of coal recovery-nearly 85% in surface mines within the minable area, as compared to an average of about 50% in underground mines. Much surface mining recovers coal that could not be extracted by underground methods because of coal bed thinness, or multiple beds close together, split seams, the nature of the roof, and other geologic conditions. What are some of the limitations of surface mining? First of all, with presently available machinery it is difficult to surface mine at depths

Jan 1, 1973

By M. E. Nicholson

IT has been suggested by a number of investigators, I including Hume-Rothery and Raynor,' that certain intermediate phases in metal systems take on interstitial crystal structures because of an appropriate ratio of radii of the two atoms. If the size factor is an important parameter in determining whether or not an intermediate phase will have an interstitial structure, then it would appear reasonable that the relative sizes of interstitial atoms should have a direct relation to their solubilities in interstitial compounds. It was on such a basis that Petch,' in his discussion of the cementite structure, concluded that nitrogen is the only possible element which could replace carbon. Recent X-ray studies by Jacka indicate that the solid solubility of nitrogen in cementite is negligible. If this is the case, then on the basis of size factor it would not be expected that any element can replace carbon in FeaC, since according to Schwarzkopf and Kieffer4 the covalent atomic radii of nitrogen, carbon, and boron are 0.71, 0.76, and 0.87A, respectively. Nevertheless, Vogel and Tammann in 1922 indicated that a quasi-binary relation exists between the interstitial compounds FeaC and Fe2B and that the solid solubility of boron in FeaC at approximately 1150°C is 1.4 pct B by weight. Because of the apparent disagreement between theory and experiment, the solid solubility of boron in FeaC has been reinvestigated. In addition, the influence of boron on the saturation magnetic moment (per gram) and Curie temperature of cementite was determined. Experimental Procedure A series of Fe-B-C alloys which varied in boron content from 0 to 5.4 wt pct B were prepared by arc melting a 50-g ingot using carbonyl iron, Ache-son AUC graphite, and Cooper grade A boron for starting materials. The composition of these alloys is listed in Table I and shown graphically in Fig. 1. The samples represented by the solid circles were used for X-ray analysis and Curie temperature measurements; by the squares, samples used for quantitative metallography; and by the triangles, samples used for saturation magnetic moment measurements and Curie temperature measurements. After arc melting and subsequent quenching from 1000°C, so that all phases in the resulting microstructure were brittle, one half of the 50-g ingots were pulverized until a powder was obtained which was less than 100 mesh. These powders were then homogenized in evacuated Vycor capsules at 1000°C for 24 hr and water quenched. Although the homogenized powder had sintered somewhat, it was suitable for saturation magnetic moment and Curie temperature determinations, for which the 60 to 100-mesh fraction of the powder was used. For X-ray analysis the homogenized powder was crushed again until a 300-mesh powder was obtained. After crushing, the powder was mixed with Alundum of approximately the same grit size to prevent sinter-

Jan 1, 1958

By T. M. Broderick

InveStIgations into the possibilities of economically mining and concentrating low-grade iron ores of the Lake Superior region are attracting increasing attention. Among the organizations that are carrying on the work are the United States Bureau of Mines, the State of Minnesota (which spends about $80,000 annually on problems of the iron and ferroalloy ores of Minnesota), and the State of Michigan (which spends about $10,000 annually of its iron-ore research). Several of the mining companies are also financing research. Of the states in the Lake Superior district, Minnesota has done most in iron-ore concentration. In 1930, thirty-seven concentrating plants were in operation on the Mesabi Range, beneficiating about one-third of the total ore shipped. About one-half of these plants reduced silica; the others reduced moisture or improved the structure of the ore.' Research into the possibilities of magnetic concentration of the Eastern Mesabi magnetite ores indicates that vast tonnages of that ore may be utilized at a profit in the not distant future. Magnetic concentration has also been tried at Sellwood, Ontario, on the Moose Mountain deposit, and at the Berkshire mine in Wisconsin on the magnetic ores of the Western Gogebic Range. There have been few attempts to concentrate Michigan iron ores. In order to determine the possibilities of such concentration, iron-ore research has been carried on at the Michigan College of Mining and Technology for the past few years. After a general survey of the iron ores of the state, a program of more detailed experimentation was outlined, starting with work on the Ironwood formation of the Gogebic Range. The results of this research led to the belief that gravity methods will produce fairly satisfactory concentrates from the parts of the iron formation that are made up of comparatively thick alternating beds of rather high-grade ore and lean chert. About 85 per cent of the iron and steel produced in the United States comes from ores of the Lake Superior district. The reserves of direct

Jan 1, 1935

By E. Houdremont, H. Schrader, H. Bennek

The different influences exerted by the various alloying elements in iron and iron-carbon alloys give rise to a great number of complexities, which are difficult to grasp. It is important therefore to study any systematic relations that may exist between the effects exerted by the various alloying elements, in order to obtain a general classification and thus a clearer conception of the nature of alloy steels. A systematic survey of the alloys of iron, based on an investigation of the binary equilibrium diagrams, was recently published by Wever. Although his work deals little with properties of importance in works practice, its purpose being rather to point out the theoretical agreement among the types of binary equilibrium diagrams and the position of the alloying elements in the periodic system (atomic radii, etc.), the classification proposed nevertheless also suggests relationships among the properties of the alloys in question, even though the alloys may contain carbon in addition to iron and the alloying element. Wever divided the alloys of iron into one group exhibiting an open or enlarged gamma field and another exhibiting a closed or restricted gamma field, with both groups capable of further subdivision depending upon whether a continuous series of solid solutions is formed, or, owing to the separation of compounds, etc., only a limited series. Thus all alloying elements which with iron form a closed gamma field, a "gamma loop," produce alloys that beyond the composition corresponding to the greatest extent of the gamma loop are composed of ferrite alone at all temperatures. Alloys of this composition accordingly are not susceptible to ordinary heat treatment because of the lack of transformations. Steels of this class may thus be divided into steels that contain less than the critical amount of alloying element, and are subject to heat treatment, and those that contain more than the critical amount of alloying element and are not subject to heat treatment. Thus chro-

Jan 1, 1935

By G. E. Goodspeed

The Cornucopia gold quartz veins form a parallel vein system traversing meta-morphic and granodioritic rocks. Field and petrographic evidence suggests that inetasomatism has played an important role both in the emplacement of the grano-diorite and in the formation of the veins. Structurally the veins appear to be related to the major tectonic features of the Wallowa Mountains and to be narrow shear zones rather than filled fissures. Petrographic studies indicate a complex history of formation starting from initial alteration along fractures or joints followed by recurrent fracturing and a quartz-forming stage, and closing with continued shearing and microbrecciation, which permitted the upward percolation of the later ore-forming solutions. The precipitation of ore minerals from these solutions formed ore shoots. Postmineral effects include the injection of Tertiary basaltic dikes, a shght amount of cross faulting, and some movement along the planes of the veins as well as oxidation. Introduction Cornucopia is in the southeastern part of the rugged Wallowa Mountains of northeastern Oregon. It was founded over 50 years ago following the discovery of its system of gold quartz veins. The major veins are roughly parallel and dip into the western side of Pine Valley, which drains the southern slope of the range. Previous operations had cut the upper portion of four major veins with two tunnels over 1000 ft. apart, when the present operating company drove a third tunnel, called the Coulter, at the level of the valley over 1000 ft. lower to intersect the most easterly major vein at over 6200 ft. from the portal. General Geology of District The oldest rocks in the vicinity are metamorphosed sediments and volcanics. These, for the most part, are presumably Mesozoic in age, although some black argillites outcropping along East Pine Creek are considered to be Permian.l,2 These rocks have been deformed and metamorphosed in general to hornfels at the close of the Jurassic. The series was then invaded by a granodiorite batholith, the origin of which is

Jan 1, 1941

By Ralph W. Smith

Development of the lime industry in Ste. Genevieve County began in a crude way in 1840. According to information furnished by the Missouri Bureau of Geology, in the early days small vertical kilns built of stone were used, and wood was the fuel. Modern development began in 1904 when one company introduced steel shells lined with firebrick. Within a few years two more companies erected similar plants, and in 1925 a fourth company began operations. Thus there arc today four lime companies at Ste. Genevieve, all operating at high capacity and with a gradually increasing production. Geology The limestone of Ste. Genevieve County, which has the chemical composition and purity required for lime burning, is the upper 80 or 90 ft, of Spergen formation. The Missouri Bureau of Geology, in its geological map of Ste. Genevieve County, gives the Spergen formation a total thickness of 160 ft., but only the upper portion is pure enough for lime burning, with an average raw-stone analysis of 98.7 per cent CaCo3; 0.35 SiO2; 0.3 R2O3; 0.35 MgCO3; 0.3 SO3. The Spergen, one member of the Meramac group, Iowa series, of the Mississippian system, underlies an area approximately 12 miles long north and south, by 5 miles wide east and west (Fig. 1) in Ste. Genevieve County. The entire eastern two-thirds of Ste. Genevieve County is sedimentary, the formations dipping gently toward the east on an average grade of about 4 per cent, or 2 1/2°. Thus the outcrops of the various sedimentaries run approximately north and south. A line running west from Ste. Genevievc crosses the outcrops of the sedimentaries, ranging from the top of the Mississippian to the Ozarkian geological system in a space of 12 miles. Thus with the gentle dip of 2 1/2° the 160-ft. thickness of the Spergen formation stretches out in its outcrop so that it is approximately one mile wide. The early quarry and lime developments at Ste. Genevieve mere in this easily obtained surface rock of the Spergen outcrop.

Jan 1, 1938

By J. H. Schloen, C. W. Clark

Two papers have been written previously concerning operations at the Montreal East plant of Canadian Copper Refiners Limited. The first one,' written in 1932, described silver-refinery operations at the time for producing silver and gold bullion from tankhouse anode slimes; the second,2 published in 1933, consisted of a description of the entire plant. Since publication of these papers the refinery has become the world's largest producer of refined selenium. The first selenium was produced in August 1934. Tellurium production on a commercial scale followed in October 1935. This paper will deal with selenium and tellurium production and also with present operations in the silver refinery. Blister cakes from Hudson Bay Mining and Smelting Co., Flin Flon, Manitoba, and commercial anodes from Noranda Mines Limited, Noranda, Quebec, are refined at Montreal East. Both these bullions have unusually high gold, selenium and tellurium content. The average assay of raw slimes produced from domestic and Noranda anodes is about 40 per cent Cu, 3600 oz. per ton Ag, 800 oz. per ton Au, 22 per cent Se and 3.7 per cent Te. Early Silver-refinery Operations From the start of operations in 1931 until July 1934, the raw slimes were oxidize-roasted at 700" I?. in a Nichols-Herreshoff furnace, acid-leached with tankhouse discarded foul electrolyte (20 per cent H²SO), filtered and charged directly to the doré furnace for refining to doré meta1. This is the customary method for treating tankhouse anode slimes but was not suitable at the Montreal East plant because of the high selenium and tellurium content of our slimes. In the acid-leaching process about 50 per cent of the selenium and tellurium in the roasted slimes was dissolved in the electrolyte. These elements were recovered with the copper as a sludge in a small electrolytic

Jan 1, 1943

By J. L. Rodda, R. L. Wilcox, E. C. Truesdale

IN recent years various problems in connection with research work on the preparation and properties of zinc-base alloys have required reliable information concerning the constitution of the zinc-rich portion of the iron-zinc equilibrium diagram. On numerous occasions rather positive indications were obtained that, for example, the solubility of iron in zinc was incorrectly represented on .the current equilibrium diagrams.. A careful study of all the available literature relating to the iron-zinc system led to the conclusion that much of the early work was unsatisfactory as measured by present standards of experimental accuracy, and as a result it was decided to redetermine the location of the liquidus curve and of adjacent portions of the diagram. Part I. of this paper comprises a description of the experimental methods and a summary of the results by means of which the zinc-rich end of the iron-zinc diagram has been revised in the following ways: 1. Measurements of the solubility of iron in liquid zinc by several different sampling methods, leading to a relocation of the liquidus curve. 2. Microscopic, conductivity, and X-ray studies of the solid solubility of iron in zinc, which, together with thermal analyses, have resulted in new values for the solid solubility and the eutectic temperature and composition. 3. Heating and cooling curves, obtained by a refined differential method, leading to new locations for the two peritectic horizontals. In Part II of the paper the attempt is made to review all of the published work having a bearing on the constitution of the iron-zinc system, and to correlate the present results, and some recently published data

Jan 1, 1935

By Frank Schrader

INTRODUCTION THE present sketch is submitted by request in the hope that it may serve as a basis for geologic discussion of the mining camps in Mohave County, which is experiencing a marked revival of activities. The region, commonly known as the Mohave district and Kingman district, lies in western Arizona in the southern part of Mohave County, bordering California and Nevada on the west (Fig. 1). Kingman, the principal-town; is situated near the center of the area. on. the Atchison, Topeka & Sante Fe Transcontinental Railway. This region is composed of naked desert ranges of mountains and broad detritus-filled valleys, the southern extension of the characteristic topography of the Great Basin. In altitude it varies from 500 ft. in the southwest to 8,300 ft. on Hualpai Peak southeast of Kingman. The mountains trend north-northwest. They rise about 3,000 ft. above the valleys, are generally rugged and were formed mainly by erosion. They are composed in the main of a, complex of pre-Cambrian granitoid rocks which underlies the area as a whole. Like the valleys, they average about 10 miles in width. Beginning on the east, they are the Grand Wash Cliffs, the Cerbat Range, the Black Mountains or River Range, and the Eldorado Range. The upper or dominantly cliff half of the Grand Wash Cliffs, marking the edge of the Colorado Plateau, is composed of nearly horizontal sedimentary Paleozoic strata of the Grand Canyon section, and the lower half of the underlying pre-Cambrian complex. The Cerbat Mountains situated in the central part of the area, and the Black Mountains situated between Detrital-Sacramento Valley on the east and Mohave Valley, the great trough of the Colorado River, on the west, are locally flanked or overlain by Tertiary volcanics (Fig. 2). The latter consist of five groups of mountains of which the most important is the Black Mesa group on the south. The Eldorado Range, rising from the great trough of the Colorado on the west and containing Searchlight, Eldorado Canyon, and other camps, is topographically and geologically similar to the Black Mountains.

Jan 10, 1916

By T. Saburi, C. M. Wayman

The massive and martensitic transformations in ß Cu-Ga alloys were studied by optical microscopy and by transmission electron microscopy and diffraction. These types of transformation are distinct and do not merge into one another. An internal fine structure due to stacking faults was found in both the massive phase (m) and the martensite, but the origin of the faults is believed to be different in each case. The faults in the martensite are due to the lattice invariant or "second" shear of the phenom-enological theory, while those in the are probably growth faults and deformation faults arising from the transformation volume change. Evidence is presented for ordering in the ß phase prior to transformation into martensite, and the crystal structures of and ß' and ßi martensites are discussed. THE results from some previous investigations1,2 have led to the suggestion that martensitic and massive transformations have certain common characteristics. It presently seems established that massive transformations like martensitic transformations are essentially diffusionless,1,2 but unlike martensitic transformations, when a new phase forms massively there is no shape change or surface relief.= If the massive-type transformation is crystallographically similar to martensitic transformations, one would expect a fine structure as a result of the lattice invariant shear4 which is a part of the transformation mechanism. The existence of such a fine structure (i.e., slip, twinning, or faulting), if any, can be verified by transmission electron microscopy, and thus the present investigation was undertaken to compare the internal structure of massively and martensitically formed phases in Cu-Ga alloys which were derived from a parent of the same composition. The transformation characteristics of ß Cu-Ga alloys were also studied. The bcc ß phase in the Cu-Ga system, Fig. 1, is stable above 616oc.' Depending upon the cooling rate, ß Cu-Ga alloys can undergo three different types of phase transformations. The ß phase of eutectoid composition (23.7 at. pct Ga) decomposes into the ? phase (hcp) and the phase (complex cubic) by means of a eutectoid reaction. When the cooling rate is increased so that the decomposition of 0 into [ and ? is suppressed, the ß phase transforms into a nonequilibrium hcp phase, herein denoted ?m by a process of very rapid growth called a "massive" transformation. At even faster quenching rates the massive transformation can be suppressed and the ß transforms martensitically. Massive transformations, apparently similar to those in the Cu-Ga system, have also been studied in the Cu-Zn2,6-8 and Ag-Cd systems.9 Definitive characteristics if the Massive Transformations in 0 Cu-Ga Alloys1 1) The most remarkable feature of the massive transformation in Cu-Ga is that there is no bulk composition change on transformation. According to Massalski,1 the resulting [, phase is a supersaturated extension of the equilibrium [ phase. The lattice parameters continue the trend exhibited

Jan 1, 1965