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By Robert Anderson

ROUGHLY, a crack in a casting may be considered, for the moment, to be due to fracture of the alloy resulting from the stress set up by the contraction in volume on passing from the liquid to the solid state. Cracks may be external or surface, internal or deep-seated, or incipient or so-called strain cracks. Draws may appear as depressions, unevenness, and "pinching in" of the surface of a casting. Roughly, draws are due to contraction in volume and are governed largely by the same factors as cracks. A casting may be cracked, however, without being drawn. Shrinkage is a foundry term; it connotes the contraction in volume of a metal or alloy on passing from the liquid to the solid state. Pattern-makers' shrinkage is the total contraction in volume (including liquid, solidification, and solid shrinkage) that occurs when an alloy is poured into a mold. The contraction in volume of aluminum is one of the principal factors affecting the occurrence of cracks, as will be shown later, and the question of shrinkage and its control requires careful study in any treatment of cracking in castings. In the case of, sand and die castings, cracks have been attributed to a number of causes, but in the case of most light aluminum alloys, they are due to the large contraction in volume on freezing and the lack of its regulation or control. The most important factors are: (1) Contraction in volume; (2) composition of alloy; (3) quality of melting charge; (4) design of casting; (5) method of molding; (6) hardness of ramming; (7) method of gating; (8) hardness and characteristics of cores; (9) chills; (10) risers; (11) melting temperatures; (12) furnace used for melting; (13) pouring tempera-tures; (14) inclusions in alloys; (15) hot shortness of alloys; and (16) physical properties of alloys at high temperatures. Of these, the first, second, third, and eleventh to sixteenth involve ascertainable metallurgical facts; the remainder are largely matters of opinion, judgment and technical knowledge of men experienced in the production of castings.

Jan 10, 1921

By John D. Verhoeven, Edward E. Hucke

An experimental technique has been developed for the measurement of the rate of electrotransport to a precision of 1 pct in the molten Bi-Sn system. Results are presented across the phase diagram from 30°C above the liquidus to 520°C. A phenomenological description is presented and the data on Bi-Sn are thereby converted to the effective charge, Analysis of the data indicates the true charge of the migrating tin species in bismuth to be +1.8 at 500°C. The data agree well with the recent work of Belashchmko. fieldintensity. The resistivity of the molten Bi-Sn system is also presented. WHEN an electric field is applied to a metal, a relatively large current is produced due to the ease with which electrons move within the metal. The electric field also produces a force on the ions which might cause them to migrate. Such a migration of metallic ions has been detected under certain conditions. This electromigration of the metallic ions will be referred to herein as electrotransport. The study of electrotransport in metallic systems has a rather long history dating back to the initial work of Gerardin1 in 1861. General reviews of electrotransport in liquid and solid metals have been published by Schwarz,2 Jost,3 Seith,4 and Heumann.5 In reviewing the literature it is apparent that the theoretical developments are not yet complete. The difficulty arises in describing the momentum transfer between the migrating ions and the electrons. In addition, there is a lack of good quantitative electrotransport data at high temperatures, especially in liquid metal systems. This work was undertaken to establish quantitative electrotransport data in a liquid metal system which might serve as a critical test of the theoretical developments. The Bi-Sn system was chosen for analysis, and the rate of electrotransport was determined as a function of temperature and composition. THEORETICAL CONSIDERATIONS If all of the atoms of a metal are considered to be positively charged due to the loss of electrons to the

Jan 1, 1963

By R. O. Harma

Introduction Wet autogenous grinding is utilized in three iron ore concentrating plants operated by the Cleveland-Cliffs Iron Company (CCI). This paper will trace some of the development in converting from the use of metal grinding mill liners to the use of rubber and will update the current performance of rubber liners in these applications. The Cleveland-Cliffs Iron Company is a natural resources firm with major interests in iron ore mining and processing and oil and gas contract drilling. The company also has interests in oil shale, uranium, forest products, and Great Lakes shipping. The three operations discussed in this paper are the Empire and Tilden Mines on the Marquette Iron Range in Michigan's Upper Peninsula and the Sherman Mine in northern Ontario, Canada. The Empire Iron Mining Partnership is managed by The Cleveland-Cliffs Iron Company and is owned by Inland Steel, McLouth Steel, The Cleveland-Cliffs Iron Company, and International Harvester. The Tilden Iron Mining Partnership is also managed by The Cleveland-Cliffs Iron Company and is owned by Algoma Steel Corporation, Ltd., Jones & Laughlin Steel Corporation, The Cleveland-Cliffs Iron Company, Steel Company of Canada, Wheeling-Pittsburgh, and Sharon Steel Corporation. The Sherman Mine is a joint venture managed by Cliffs of Canada, Ltd. and owned by Dominion Foundries and Steel Company, Ltd. and Tetapaga Mining Company, a wholly owned subsidiary of The Cleveland-Cliffs Iron Company. The concentrators at all three mines utilize two stage autogenous grinding. Empire and Sherman process magnetic iron ores (Table 1) and utilize magnetic, hydraulic, and flotation concentration methods. Tilden processes an oxidized iron ore (martite, goethite, and hematite) and utilizes a selective-flocculation desliming and flotation concentration flowsheet. Final grind particle sizes are 90% -325M (43k) at Sherman, 90% -500M (25,u ) at Empire and 85% -500M (25 µ) at Tilden. Developmental History The success of using rubber mill linings in Scandinavia led to the first rubber mill lining used by CCI. It was installed in a conventional primary ball mill at Republic Mine in 1964 as reported by Lindroos (1970). This was followed by additional rubber liners for both primary and regrind ball mills. Generally these rubber linings provided about twice the service life as compared to the Type I Ni-hard liners previously used. Grinding efficiency of rubber was found to

Jan 1, 1982

By F. E. Smith, David R. Mitchell, B. M. Bird

DENSE-MEDIA processes utilize the familiar laboratory float-and- sink procedure on a commercial scale. Just as wood chips float on water and sand sinks, ,so coal floats and refuse sinks when placed in a medium intermediate in specific gravity between the coal and refuse. Liquids intermediate in specific gravity between coal and refuse used in commercial plants are of four types: (1) Organic liquids of high specific gravity-halogenated hydrocarbons; (2) dissolved, salts in water; (3) pseudo liquids obtained by suspending solids, such as sand, in water, and (4) fluidizing a mass of sand or other solids by air currents. Those most widely used for cleaning coal are solutions of calcium chloride in water and a suspended-sand pseudo liquid. Laboratory float-and-sink testing is an intermittent operation during which every opportunity is given for particles lighter than the medium to float and particles heavier to sink. Commercial processes are continuous, vertical and horizontal currents of the separating medium occur as either part of the process or unavoidably produced by the introduction of feed and withdrawal of products, so that the exact separation of the laboratory technique is not duplicated by commercial processes. However, separations close to the theoretical are obtained in commercial machines by careful technical control of the process. Most machines in commercial installations are crowded to get as much out of the equipment as possible, so that careful technical control is necessary to get the recoveries and grade of product desired. Sizes usually cleaned are plus 3/16-in. or plus 1/8-in. in the United States and plus 1/16-in. in Great Britain: Coal as small as 1 mm. has been cleaned in some experimental installations. The separation of coal from refuse in sizes finer than about in. is made difficult by viscosity' effects and hence at the present time cleaning is confined to the coarser sizes. Technical advances in the art of cleaning coal by dense-media

Jan 1, 1943

By J. M. Lovejoy

Various estimates have been made as 60 the percentage of oil left in a field after the wells have become so small that it is no longer practical to produce them. Engineers have given the matter much study and can substantiate their figures by data taken from fields from the Appalachians to California. The average oil sand has a porosity of about 20 per cent., which gives a capacity per acre-foot of approximately 1500 bbl. The sand thickness in Oklahoma pools averages 20 ft. With 20 per cent, porosity and a 20-ft. sand thickness, the capacity per acre is 30,000 bbl., yet these pools will seldom yield more than 5000 bbl. to the acre. These figures gupport the theory that at least 50 per cent. of the oil remains in a sand after all known methods to recover it have been used. Certainly we can never recover all the oil, unless in years to come oil becomes so rare and yet so necessary that the price will justify sinking shafts into the abandoned fields and regular mining methods of drifting and stoping. However, with improved methods of production and conservation of the natural agencies of expulsion, we should be able to increase recovery. It is with this in mind that this paper, relating to the effect of back pressure on wells, is presented. Except in the fields where production is caused by hydrostatic pressure, the chief agency for getting oil out of the sand into the hole is the gas that occurs with the oil. After the pressure has declined, probably gravity also is a factor, but not an important one. With a given amount of oil in a sand and a given amount of gas occurring with the oil, the ratio of gas volume per barrel of oil is the key to the ultimate recovery from that sand. Our efforts should be along lines that will lower this ratio and make the gas, the agency given us by nature, do its work better and yield more of the oil, of which it is a part. T. E. Swigart,' of the U. S. Bureau of Mines, has published an extract of the paper he is preparing under the title "The Effect of Back Pressures. on Wells." The experiments described were made on two

Jan 1, 1924

By B. Tani, K. Anderson, I. Johnson, R. Schablaske

INVESTIGATION of the various rare earth-cadmium binary systems discloses the existence of a compound corresponding to the composition MCd6 in all systems save the La-Cd system. Lattice constants for all of the MCde compounds, except LaCd6 which apparently does not form, and PmCd6 whose synthesis was not attempted, are also recorded herein. Iandelli and Ferro 1 report the existence of the compound CeCd6. No additional information, structural details, and so forth are given. Elliott and Lemons2,3' have measured the vapor pressure of cadmium over CeCd6 and have calculated the activity of cadmium in solid CeCd6. These authors find that CeCd6 exists over a composition range from 5.967 to 6.098 (Cd:Ce ratio) at 584oC, and from 5.971 to 6.118 at 639°C. The following is an excerpt from the paper by Elliott and Lemons: 2 "Recently Mr. F. H. Ellinger of this laboratory has indexed an X-ray diffraction powder pattern of CeCd6.00 which we had prepared by gas phase reaction. The compound has a primitive cubic unit cell with a = 15.783 + 0.001A Based on the volume of the cubes surrounding an elemental cerium or an elemental cadmium atom, Mr. Ellinger finds room for 24.10 CeCd6 formula units in the CeCd6 unit cell; similar calculations based on CeCd2 and CeCd11 yield 24.18 formula units per unit cell. The presence of 24 CeCd6 units per unit cell seems probable with an X-ray density of 8.255 grams per cubic centimeter. The most one can say about in-terstitial~ is that there appears to be room in the crystal even at room temperature." Measurements of the solubility of the rare earths in liquid cadmium4 led to the discovery of GdCd6,

Jan 1, 1964

By L. C. McCabe

This paper is a progress report on a study of the distribution of the banded ingredients (Figs. 1 and 2) in Illinois screenings and the method of determining their distribution. Proximate analyses and screen tests1 have been reported and a further report on the washability characteristics of the screenings is in preparation. The microscopic study of the screenings is not yet far enough advanced to permit a conclusive report on the effect of mining, screening and washing on the distribution of the banded ingredients in the coals of Illinois. However, considerable fundamental data have been collected as a background for the screenings investigation and for a proposed study of fuels composed of known quantities of vitrain, clarain and fusain, the three common banded ingredients of Illinois coals. These fundamental data and the preliminary information now available from the microscopic study of screenings are broadly indicative of the reaction of the coals to the physical processes affecting them in mining and preparation. Proximate analyses of samples of vitrain, clarain, and fusain from several Illinois mines have been published2, but those given in Table 1 serve to show the differences that are apparent in proximate analyses. The vitrain samples are consistently low in ash, and the unit-coal value is uniformly lower than in clarain. The average fuel ratio (F.C./V.M.) of the vitrain samples in the table is 1.57 whereas the clarain average is 1.42. The fusain analyses vary considerably in ash and moisture. In the two samples from this mine the moisture values range from 8.99 to 22.80 and the ash from 4.86 to 16.91 per cent. Fusain has higher fixed carbon than either vitrain or clarain but the percentage is erratic from sample to sample. The relative proportions of the banded ingredients in the Herrin (No. 6) coal in Illinois is reasonably well known but detailed information

Jan 1, 1936

By L. C. McCabe

This paper is a progress report on a study of the distribution of the banded ingredients (Figs. 1 and 2) in Illinois screenings and the method of determining their distribution. Proximate analyses and screen tests1 have been reported and a further report on the washability characteristics of the screenings is in preparation. The microscopic study of the screenings is not yet far enough advanced to permit a conclusive report on the effect of mining, screening and washing on the distribution of the banded ingredients in the coals of Illinois. However, considerable fundamental data have been collected as a background for the screenings investigation and for a proposed study of fuels composed of known quantities of vitrain, clarain and fusain, the three common banded ingredients of Illinois coals. These fundamental data and the preliminary information now available from the microscopic study of screenings are broadly indicative of the reaction of the coals to the physical processes affecting them in mining and preparation. Proximate analyses of samples of vitrain, clarain, and fusain from several Illinois mines have been published2, but those given in Table 1 serve to show the differences that are apparent in proximate analyses. The vitrain samples are consistently low in ash, and the unit-coal value is uniformly lower than in clarain. The average fuel ratio (F.C./V.M.) of the vitrain samples in the table is 1.57 whereas the clarain average is 1.42. The fusain analyses vary considerably in ash and moisture. In the two samples from this mine the moisture values range from 8.99 to 22.80 and the ash from 4.86 to 16.91 per cent. Fusain has higher fixed carbon than either vitrain or clarain but the percentage is erratic from sample to sample. The relative proportions of the banded ingredients in the Herrin (No. 6) coal in Illinois is reasonably well known but detailed information

Jan 1, 1936

By John Chapman, J. C. Vaughan

Although a considerable amount of practical importance attaches to systems involving gases and molten metals, little is known regarding the effects of alloy elements upon the solubility of gases in liquid iron. The solubilities of hydrogen1 and nitrogen2,3 in pure liquid iron arc known and it has been shown that small amounts of silicon and aluminum3 exert only a small effect upon the solubility of nitrogen but greatly increase its rate of solution. This paper presents the results of a study of the solubility of nitrogen, at pressures approximately one atmosphere, in molten iron containing up to 15.8 per cent silicon. EXPEBIMENTAL METHOD There are two general methods by which the solubility of a gas in a molten metal may be determined. In the first, which Sievertsl employed, the gas is measured from a burette into the enclosure containing the metal and the amount absorbed is found by subtracting from the total volume that of the dead space in the container. The second method, which was used successfully for pure liquid iron, is to expose the molten metal to the gas until absorption ceases, then to solidify and analyze the metal. In either method the stirring produced by inductive heating prevents the development of a stagnant layer at the metal surface and ensures actual attainment of equilibrium. Obviously the second method is accurate only when the saturated metal is capable of solidifying without gas evolution. Since the rate of solution of nitrogen in iron is increased by the presence of silicon, it was to be expected that the rate of evolution would be correspondingly increased and for this reason the first method was selected. A sketch of the furnace is shown in Fig. 1. A small high-frequency coil having 17 turns fitted closely around a fused silica tube, 2 in. in diameter, in which was placed, on a bed of 60-mesh alumina sand, an

Jan 1, 1940

By J. C. Vaughan, John Chapman

Although a considerable amount of practical importance attaches to systems involving gases and molten metals, little is known regarding the effects of alloy elements upon the solubility of gases in liquid iron. The solubilities of hydrogen1 and nitrogen2,3 in pure liquid iron arc known and it has been shown that small amounts of silicon and aluminum3 exert only a small effect upon the solubility of nitrogen but greatly increase its rate of solution. This paper presents the results of a study of the solubility of nitrogen, at pressures approximately one atmosphere, in molten iron containing up to 15.8 per cent silicon. EXPEBIMENTAL METHOD There are two general methods by which the solubility of a gas in a molten metal may be determined. In the first, which Sievertsl employed, the gas is measured from a burette into the enclosure containing the metal and the amount absorbed is found by subtracting from the total volume that of the dead space in the container. The second method, which was used successfully for pure liquid iron, is to expose the molten metal to the gas until absorption ceases, then to solidify and analyze the metal. In either method the stirring produced by inductive heating prevents the development of a stagnant layer at the metal surface and ensures actual attainment of equilibrium. Obviously the second method is accurate only when the saturated metal is capable of solidifying without gas evolution. Since the rate of solution of nitrogen in iron is increased by the presence of silicon, it was to be expected that the rate of evolution would be correspondingly increased and for this reason the first method was selected. A sketch of the furnace is shown in Fig. 1. A small high-frequency coil having 17 turns fitted closely around a fused silica tube, 2 in. in diameter, in which was placed, on a bed of 60-mesh alumina sand, an

Jan 1, 1940

By Martin T. Broome

INTRODUCTION The Luanshya Mine is situated in the southern part of the Zambian Copperbelt. The copper ore deposit is stratiform, and is preserved in a synclinorium known as the Roan/ Muliashi basin. Roan shaft (formally called No.14 shaft) is located at the eastern end of the syncline and is theoldest of the presently operating hoisting shafts, being sunk during the 1930's. It presently hoists some 45 per- cent of the total Luanshya Mine production. A cross-section through the shaft is shown in figure 1. The ore formation on the south limb is unmined on this section because until recently it was believed that such mining might cause damage to the shaft. This paper examines the influences of adjacent mining on this so-called 'shaft pillar', and describes the mechanics of subsidence of the pillar itself. GEOLOGY AND STRUCTURE Figure 1 shows the general form of folding in the vicinity of Roan shaft. The north and south limbs of the main syncline approach parallelism, with the bottom of the trough fairly smoothly rounded. The axis of the - trough plunges to the west-north-west at 6° - l0°. A brief summary of the major lithologies present in the Roan basin is given in table 1, however, the performance of the overall structure during progressive mining of the ore horizon is controlled by the following features in addition to the mining method. Intraformational Contacts These are characteristically weak in most geological environments. The BC/RL7 contact is an unconformity between moderately weak quartz-biotite schists below (unconfined compressive strength 40 - 80 MN/M 2), and strong quartzites above (U .C .S. 170-200 MN/M2) Subsequent formations are conformable, and planes of weakness are generally the result of contrasting lithology (see below). Weak Interbeds The Rt7, RL6, RL5, RL3 and RU2 horizons consist predominantly of quartzitic rocks, i.e. conglomerates, quartzites and argillites, and as such are generally strong and considered suitable for the positioning of development. Between these however, lie two much weaker dolomitic horizons, the RL4 and RU1. The Rt4 is the main hangingwall aquifer, and must be drained prior to mining. Drainage results in an extremely weak, blocky cavernous horizon which usually requires support if exposed by development. Similarly, the RU1 formation is comprised mainly of dolomites and dolomitic arqillites which are weak and cavernous. In the eastern part of the Roan/

Jan 1, 1981

By Philip M. Mc Kenna

When a new material becomes available to industry, it is useful to describe its properties as a guide to its most effective application; and when the new material may be produced in compositions having a series of graded properties, tests to select the combination of properties best adapted for various uses are helpful. The class of materials to be considered in this paper are hard tool materials produced by processes of powder metallurgy from hard carbide constituents and various matrices of iron, nickel or cobalt, or alloys of them with tungsten, or tungsten and carbon. The customary use of carbide hard alloys is for metal-cutting tools; although wire-drawing dies, lathe centers, follow rests, grinding rests, burnishers, rolls, extrusion dies, measuring gauges and micrometers, and a number of other tools are also made with these hard alloys as the essential wear-resisting parts. The properties and tests to be considered are those affecting these uses. In the development of tool materials since the industrial revolution we have had carbon tool steels, Mushet steel, high-speed steels, stellites, and now cemented carbide compositions. For an understanding of the latter category of materials their properties and uses relative to the older and more familiar tool materials will be considered. Hardness has been the property of greatest practical interest in tool materials. The word "hardness" is a generalized term lacking definite-ness unless the specific test used is described. However, efforts to explain physical properties as a consequence of chemical bond, and distance between atoms in chemical compounds have been illuminating. This seems the most generalized attack on the problem, and is based upon the idea that atoms in a lattice are held together as the square of the valence and inversely as the square of the distance between the atoms. The compounds compared must all be of the same crystalline arrangement. 100 W2 It is interesting to note the values of the figure 7 A 3 /3for a number of

Jan 1, 1938

By Philip M. Mc Kenna

When a new material becomes available to industry, it is useful to describe its properties as a guide to its most effective application; and when the new material may be produced in compositions having a series of graded properties, tests to select the combination of properties best adapted for various uses are helpful. The class of materials to be considered in this paper are hard tool materials produced by processes of powder metallurgy from hard carbide constituents and various matrices of iron, nickel or cobalt, or alloys of them with tungsten, or tungsten and carbon. The customary use of carbide hard alloys is for metal-cutting tools; although wire-drawing dies, lathe centers, follow rests, grinding rests, burnishers, rolls, extrusion dies, measuring gauges and micrometers, and a number of other tools are also made with these hard alloys as the essential wear-resisting parts. The properties and tests to be considered are those affecting these uses. In the development of tool materials since the industrial revolution we have had carbon tool steels, Mushet steel, high-speed steels, stellites, and now cemented carbide compositions. For an understanding of the latter category of materials their properties and uses relative to the older and more familiar tool materials will be considered. Hardness has been the property of greatest practical interest in tool materials. The word "hardness" is a generalized term lacking definite-ness unless the specific test used is described. However, efforts to explain physical properties as a consequence of chemical bond, and distance between atoms in chemical compounds have been illuminating. This seems the most generalized attack on the problem, and is based upon the idea that atoms in a lattice are held together as the square of the valence and inversely as the square of the distance between the atoms. The compounds compared must all be of the same crystalline arrangement. 100 W2 It is interesting to note the values of the figure 7 A 3 /3for a number of

Jan 1, 1938

By Raymond Sanford

IT IS difficult to know just when a hoisting rope should be removed from service and a new one substituted. It is desirable to utilize the full life of a rope but, on .the other hand, the damage and possible loss of life, resulting from delay in replacing it may amount to many times the cost of a new rope. In the present methods of inspection the inspector must rely upon accumulated experience and a certain sixth sense or intuition in addition to any rules that may be laid down regarding the number and distribu-tion of broken wires. This condition does not neces-sarily arise from lack of interest among users or makers of rope, but is due rather to the lack of satisfactory or adequate methods for testing ropes to determine their exact condition. The main difficulty in devising a physical test lies in the fact that a number of causes, all operating in different ways, contribute to the deterioration of a rope in service, and affect not only the external conditions but also the inner structure of the material of which the rope is constructed. Wear and broken wires on the outer part of the rope are not difficult to detect, but a test is needed which will clearly indicate the presence of broken wires in the interior portions and the change in strength due to alterations in the structure and properties of the material itself.

Jan 7, 1923

By T. O. Massalski, J. D. Ayers

A massive transformation, 0 —am, takes place in a number of copper-based systems where the ß phase field at high temperatures extends to compositions that are slightly less solute-rich than the limits of the a phase field that exists at lower temperatures. Consequently a solid-state transformation becomes possible that does not involve a change of composition. Within this narrow range of composition the massive am phase can be usually produced in two ways: by a fast quench from the ß phase through the a phase field, or by pulse heating into the a phase field of an undecomposed ß phase retained at room temperature by a prior quench. In the Cu-Ga system the occurrence of a massive am phase has been also observed in alloys whose composition falls outside the equilibrium a phase field1 but not in the Cu-Zn system.2 We have recently observed the occurrence of the ß — am transformation also in two silver-based systems, Ag-Zn and Ag-Cd. The a and 0 phase fields in these systems again slightly "overlap" in a narrow composition range. In the Ag-Zn system this range falls between 36.7 and 40.2 at. pct Zn, and in the Ag-Cd system between approximately 41 and 42.5 at. pct Cd. Alloys were prepared from high-purity materials and cast in quartz tubes under inert atmosphere. No significant change of composition occurred during casting. After homogenizing in the 0 phase field, small pieces of each alloy were reheated at the homogenizing temperatures for a few minutes and quenched into various media. There were examined metallographic-ally after removal of surface layers that may have suffered from contamination or from the loss of the solute element. In the Ag-Zn system extensive areas of the am phase (identified by selective etching, observation of the slip trace variants, and occurrence of twinning) were observed in a comparatively low-zinc alloy (37.8 at. pct Zn) for all quenching media employed: iced

Jan 1, 1969

By H. l. Burghoff, D. E. Lawson

The presence of tellurium in copper and, by inference, in copper alloys, has been considered seriously detrimental and has been avoided. In particular, very small amounts of tellurium have been found to produce red-shortness, although the effects on cold-working and ordinary physical and mechanical properties have not been known so definitely. References in the literature are few, but as long ago as 1881, Eglestonl reported that 0.083 per cent tellurium in fire-refined copper rendered the copper red-short and therefore worthless for hot-rolling. In hot-rolling copper cakes containing this amount of tellurium, he found that fine cracks appeared in the cakes on the first pass through the rolls, the cracks opening further in successive passes. When cold, the metal was said to be tough and malleable. A few years ago, during the course of an investigation in our laboratory on copper-base alloys, it was found that tellurium-bearing alloys could be machined much more freely than similar alloys not containing tellurium. The study was pursued further in this direction, and considerable data were obtained, which indicated that certain tellurium-bearing alloys might have properties of commercial interest. The work eventually led to patent protection,2 a wide range of tellurium-bearing copper-base alloys being covered. This article presents results obtained on the effect of tellurium on the mechanical properties of three copper-base alloys: commercial bronze (90 Cu, 10 Zn), 1.5 per cent tin bronze (98.5 Cu, 1.5 Sn), and silicon bronze (96 Cu, 3Si, 1 Zn). Several alloys were cast in each series, with tellurium content ranging from 0 up to about 1 per cent. The alloys were melted under charcoal in a clay-graphite crucible, using a high-frequency induction furnace, and were cast without undue difficulty in rod form, 15/8 in. in diameter. Charges for the zinc and tin series were made up from the following materials: cathode copper, electrolytic zinc, tin, and tellurium in slab

Jan 1, 1938

By H. l. Burghoff, D. E. Lawson

The presence of tellurium in copper and, by inference, in copper alloys, has been considered seriously detrimental and has been avoided. In particular, very small amounts of tellurium have been found to produce red-shortness, although the effects on cold-working and ordinary physical and mechanical properties have not been known so definitely. References in the literature are few, but as long ago as 1881, Eglestonl reported that 0.083 per cent tellurium in fire-refined copper rendered the copper red-short and therefore worthless for hot-rolling. In hot-rolling copper cakes containing this amount of tellurium, he found that fine cracks appeared in the cakes on the first pass through the rolls, the cracks opening further in successive passes. When cold, the metal was said to be tough and malleable. A few years ago, during the course of an investigation in our laboratory on copper-base alloys, it was found that tellurium-bearing alloys could be machined much more freely than similar alloys not containing tellurium. The study was pursued further in this direction, and considerable data were obtained, which indicated that certain tellurium-bearing alloys might have properties of commercial interest. The work eventually led to patent protection,2 a wide range of tellurium-bearing copper-base alloys being covered. This article presents results obtained on the effect of tellurium on the mechanical properties of three copper-base alloys: commercial bronze (90 Cu, 10 Zn), 1.5 per cent tin bronze (98.5 Cu, 1.5 Sn), and silicon bronze (96 Cu, 3Si, 1 Zn). Several alloys were cast in each series, with tellurium content ranging from 0 up to about 1 per cent. The alloys were melted under charcoal in a clay-graphite crucible, using a high-frequency induction furnace, and were cast without undue difficulty in rod form, 15/8 in. in diameter. Charges for the zinc and tin series were made up from the following materials: cathode copper, electrolytic zinc, tin, and tellurium in slab

Jan 1, 1938

By H. J. French

Within the past few years, particularly because of the rapid growth of the airplane industry during the war, considerable attention has been paid to the manufacture of light-wall cold-drawn seamless and welded steel tubing for structural purposes. While the manufacture of such tubing is not, in itself, a difficult matter, some difficulties have been encountered in producing the same under specifications requiring definite physical properties. It is the purpose of this paper to describe the methods of manufacture and the properties that may be obtained by such methods for tubing coming within about 1/2 to 2 in. (12.7 to 50.8 mm.) outside diameter and 10 to 22 Birmingham wire gage (0.134 to 0.028 in. wall thickness). Such tubing is largely used as structural material in the aircraft industry, and it is of the utmost importance that the physical and chemical properties should be known, and also that the various factors entering into the manufacture should be under such control as to allow these properties to be varied and held within definite limits. In general, tubing may be divided into four classes: namely, specialty tubing, such as riveted-sheet or plate, lock jointed, etc.; brazed tubing; welded tubing; and seamless tubing. Welded tubing may be divided into hot product, such as lap welded and butt welded, and cold product, such as acetylene and electric welded. Seamless tubing may be hot rolled or cold drawn. Specialty Tubing The first two classes present mainly mechanical or structural engineering problems. A simple form of tube is made by riveting together the overlapping edges of rolled sheets or plates formed into a cylinder. Because of the nature of its construction, such a tube is necessarily limited to relatively large sizes. Lock-jointed tubing is produced by passing low-carbon strip through a forming machine having suitable rolls and dies, its manufacture is almost entirely a question of design of the forming machine and its satisfactory operation. The chief application of such tubing is in the manufacture of bedsteads.

Jan 1, 1920

By Ralph Schilthuis

SEVERAL investigators1-8 have reported evidence of the existence of native or connate water in oil-and-gas-bearing strata. Both water and salt have been detected in cores of oil sands that yielded oil and gas exclusively when produced. Electrical logs often reveal unexpectedly low resistivity through oil and gas sands, indicating the presence of some material that is a considerably better conductor of current than oil and gas. Furthermore, calculations9 of the oil and gas content of reservoirs based upon production and reservoir-pressure decline data indicate appreciably lower values than are arrived at under the assumption that the pore space is occupied completely by oil and gas. ORIGIN AND OCCURRENCE OF CONNATE WATER IN OIL-AND-GAS-BEARING FORMATIONS The view has been expressed,10-15 and is generally agreed upon, that the expulsion of oil and gas material from source beds and the subsequent migration and accumulation occurred in the presence of salt water. As the strata that usually form reservoirs for oil and gas were laid down by, or in the presence of, ancient seas, the pore space within the strata must have been saturated with salt water before the entrance of the oil and/or gas. Thus, the accumulation of oil and/or gas in the upper regions of structures suitable for reservoirs must have required displacement of the connate water therefrom. In the absence of any forces other than gravitational, it would be expected that the displacement of the connate water out of the zones finally occupied by gas and oil would be complete, and that the vertical distribution of gas, oil, and water in a reservoir would be strictly in the order of their densities. Apparently, however, surface and interfacial forces that will not permit complete segregation of the fluids are active within the capillary spaces comprising a reservoir. The effects of these forces on both accumulation and production of oil and gas have been the subject of study by a number of investigators. 16-37

Jan 1, 1938

By L. Stone, H. Margolin

The Ti-C-N and Ti-C-O systems were investigated in the temperature range from 500° to 1400°C and in the composition range up to 2 pct C and 5 pct N or 0. Characteristic isothermal sections at 800°, 900°, 1000°, and 1300°C are presented. The Ti-N-0 system was studied in the temperature range from 900' to 1400°C with alloys containing up to 6 pct total alloying content. Characteristic isothermal sections at 1000° and 140O°C are presented. Melting-point data for all three systems are also included. THIS paper reports on one of a series of investi-gations which have been conducted on the phase diagrams resulting from interstitial alloying with iodide titanium. The other investigations involved delineation of the binary systems with carbon,' nitrogen and boron,h and oxygen. The Ti-0 binary system has also been investigated by Bumps et al.' In varying degrees, each of these interstitial elements has been shown to stabilize the low temperature a modification of titanium1-5 and each forms a face-centered cubic TiX compound (henceforth designated 6). In addition, the Ti-N and Ti-0 systems reveal a low temperature tetragonal phase (6) formed by a peritectoid reaction between a and TiX Experimental Procedure The development of experimental techniques for the study of titanium alloy systems has, to a large extent, become standardized. In this investigation, the equipment and procedures described in detail by Cadoff and Nielsenl have been used. Arc Melting: In general, binary alloys with carbon, nitrogen, and oxygen, prepared in the composition range of interest in this investigation, show negligible composition changes during arc melting. However, the possibility of the formation of some gaseous combination of alloying elements such as CO, CN, or NO during the preparation of these ternary alloys was considered. Calculations showed that the evolution of only 0.05 gram of such a gas would be detectable as a pressure change in the closed system used during preparation of these alloys. Such pressure changes were not observed. Consequently, nominal compositions have been used in plotting the data. The compositions of the materials used in the preparation of the alloys are shown in Table I. After melting for 3 to 5 min at 275 to 350 amp, the alloys were checked for homogeneity by microstruc-tural examination. Alloys containing up to 1 pct C were homogeneous in the presence of less than 3 pct N or 0. At higher alloying contents, some inhomo-geneities in the carbon distribution became evident. Alteration of the melting procedure toward longer times and higher currents did not improve the homogeneity of these alloys. Ti-N-0 alloys were homogeneous in the range to about 3 or 4 pct total alloying addition. Beyond this, almost all of the specimens showed as-cast microstructures consisting only of the phase. Consequently, inhomogene-ities could not be detected by examination of micro-structures. Ten alloys from each of the systems were analyzed for two of the elements present (oxygen being omitted in all cases and titanium being omitted in the Ti-C-N alloys). In all cases the analyses were found not to be sufficiently precise to serve as criteria for the total composition of these alloys. On the basis of phase distribution in heat-treated alloys, however, it appears that carbon is distributed throughout the alloys most uniformly, with oxygen and nitrogen following in that order. Heat Treatment: Specimens for heat treatment were wrapped in titanium sheet before sealing in the argon-filled quartz capsules. Heat-treatment times varied from 100 hr at 800°C to 0.5 hr at 1400 °C. After heat treatment the specimens were quenched by breaking the capsule in water. With the exception of alloys in the low composition region, heat treatment did not have an appreciable effect on the as-cast microstructures. Metallography: Following heat treatment, the specimens were prepared for metallographic examination by grinding on emery paper and electrolytic polishing. For the majority of the specimens a 10-sec etch with Remington "A" agent (25 pct HNO3, 25 pct Hf, and 50 pct glycerin) adequately

Jan 1, 1954