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By S. A. Swensrud

NINETEEN Thirty-Six was the biggest year in volume in the history of the oil industry, and unquestionably the best since 1929 in respect to profits. The quota of new and difficult problems to face seemed a little smaller during 1936 than in most recent years, and a somewhat better balance existed between the different branches of the industry. 'Domestic consumption of gasoline in 1936, estimated at about 475 million barrels-the highest on record, was approximately 11 per cent above 1935, and 26 per cent above 1929. Demand for crude oil increased in about the same proportion: over 1935, and the average production, of about three million barrels daily,' constituted a new high level.

Jan 1, 1937

By Walter R. Hibbard, Ming-Kao Yen

VARIOUS rationalizations of preferred orientations in cold worked polycrystalline metals have been based on the operation of at least two,1 three,2 five,4 an indefinite number,5 and all,6 slip systems of the type occurring in single crystals. Pickus and Mathewson3 suggested that the cold rolling texture in face-centered cubic metals could be rationalized on the basis of two or more operating slip directions symmetrically disposed about the direction of flow in such a manner that the resolved shear stress factor is equal for all operating slip systems and lattice rotations cancel each other. The importance of the direction of flow, † the necessity for the operation of slip systems capable of producing the required, changes in external dimensions, the maintenance of a common surface between adjacent grains and a symmetrical arrangement of the operating slip systems in order to produce an end orientation which is stable under additional deformation lead to the following rationalization of textures based on the type of slip systems operative in single crystals. The rationalization is intended to explain why certain orientations are suitable for deformational flow without a change in orientation and thus are stable end orientations or ideal texture orientations. It does not attempt to explain how the grains of a randomly oriented polycrystalline aggregate will reach this orientation. The rationalization is based on the following four postulates: I. The ideal textures for polycrystalline aggregates are the result of reorientations of individual crystals toward the same stable end orientation at which no further reorientation will occur even during additional deformation. Since, in simple slip, - the relative orientations of the stress axis and the active slip system determine the change in orientation during slip, it is considered that the orientation of the stress axis with respect to the ideal texture determines what slip systems must be active to retain the stable end orientation. Therefore the stable end orientation should be a symmetrical one around the stress axis with respect to the active slip systems such that lattice rotations resulting from slip will cancel each other and prevent a resultant change in orientation. (Rotational symmetry only-not translation, inversion, nor others-is considered here.) Thus a metal under a pure stress should develop a texture consisting of one or more of the crystallographically symmetrical directions, <100>, <110> or <111> for cubic metals or <0001>, <1010> or <1120> for hexagonal dose-packed metals, parallel to the stress axis. 2. Since the active slip direction is the direction of glide during simple slip and thus the direction of maximum shear movement, in the ideal texture the active slip

Jan 1, 1948

By J. W. Leonard

This expanded and more detailed supplement to earlier published work1 is offered as a means to demonstrate the high empirical correlation which exists between the readily measured coal bench scale test parameters of volatile matter (d & a.f.), Hard-grove grindability index (HGI), Koppers cone bulk density (BD) and pulverization level (% passing a 1/8-in. screen) to the less readily measured full scale coke stability index. Thus, Fig. 1, 2 and 3 represent the correlated test data contained in Tables I, II and III respectively. Ninety-six coals are correlated so that 97% of the resultant cokes fall within two points and 100% fall within three points of the actual tested coke stability indices. The main generalizations which can be drawn from the correlation of these coals are as follows: 1) The coke stability indices for higher bulk density coals (46.0 BD to 50.6 BD) appear to be largely influenced by differing combinations of factors for coals above and below a pivotal point of approximately 36% to 37% volatile matter. Below this pivotal volatile matter coke stability index appears to be influenced largely as a result of changes to the coal volatile matter and pulverization level. While above this pivotal volatile matter coke stability indices appear to be dependent on the coal hardness, as measured by the HGI, and to some extent upon coal volatile matter. Pulverization appears to have little influence on the coke stabilities of the harder coals (52 HGI to 58 HGI) of greater than 36% to 37% volatile matter. 2) The coke stability indices for lower bulk density coals (41 BD to 45.9 BD) appears to be largely influenced by changes to coal volatile matter and pulverization level for softer coals above approximately 58 HGI. 3) The main empirical observation to be drawn from these results is that for coals above approximately 36% to 37% volatile matter the quantities of hard and soft constituents as measured by the HGI are important when defining coal rank for correlation to the coke stability index.

Jan 1, 1965

By R. M. Keeney

Before the outbreak of the war in 1914, the only electric-furnace smelting plant operating on a commercial basis west of the Mississippi River was an electric pig-iron plant in California; rare metal ores were not smelted, concentrates of molybdenum, tungsten, uranium, and vanadium ores being shipped East for reduction. Practically no chrome ore was being mined, and only comparatively small amounts of manganese ore. Today there are two electric smelting plants in California, one in Washington, one in lowa, and four in Colorado; two plants are under construction in California, and one in Montana. Ores of manganese, chromium, molybdenum and tungsten are now smelted in the West, and although uranium and vanadium concentrates are still shipped to the East, they will probably be treated in western plants in a short time. The four electric-furnace plants in Colorado are listed in Table 1. Table 1.—Electric Smelting Plants in Colorado Capacity. Company Location KilowattB PRoductS Tungsten Products Co........... Boulder 800 Ferrotungsten, ferromo- lybdenum. Boulder Tungsten Production Co .. Boulder 400 Ferrotungsten. Ferro Alloy Co.................. Utah Junction 1200 Ferrochrome, ferrotung- sten. Iron Mountain Alloy Co......... Utah Junction 3000 Ferromanganese. Power for all of these plants is supplied by the Colorado Power Co. The plant of the Ferro Alloy Co., at Utah Junction, contains one 750-kw., three-phase furnace, to which power is supplied by three 250-lrw. transformers, connected /Y to give 129 volts on the furnace cables, the transformer ratio being 13,200 to 75 volts. The furnace operates with an actual voltage of 120 volts, and produces about 3 tons of ferrochrome per 24 hr. from 40-per cent. Cr2O3 ore. The furnace consists of a steel shell of circular cross-section, 8 ft. (2.43 m.) in diameter by 7 ft. (2.13 m.) deep, lined with magnesite, and having three vertical carbon electrodes 12 in. (30.48 cm.) in diameter. A 450-kw. furnace, of the same size as the 750-kw. furnace, is also operated on chrome ore. This furnace is three-phase in appearance, but operates electrically as a single-phase furnace. There are three vertical

Jan 1, 1920

By J. M. McDowell

A study has been made to deter~r~irre how the behavior of a water drivee reservoir changes as a function of the permeability of the formation and as a function of the size of the aquifer. The effect of pressure maintenance programs on the rote of nat11rn1 water influx is also studied, (IS well as the influence on the influx of the position of water injection we1ls with reference to the oil-water contact. The results are determined by the use of an electrical reservoir analyzer and are plotted as families of curves of pressure, natural water influx, and water injection vs time or cumulalive production. Two size aquifers are studided. One is limited with a 36-inile radius, and the, other approximates an infinite reservoir. The field remains the same in all respects for the completed. study except that the permeability is changed to agree with that assumed for the aquifer. 1 N TR ODUCTI ON this study was undertaken in -dcr to determine how the pres- sure decline and water influx of a water drive field would change as a function of the rate of fluid withdrawals, as a function of the permeability of the formation, and as a function of the size of the aquifer. The effect of pressure maintenance programs on the rate of natural water influx was also studied as was the position of water injection wells with reference to the oil-water contact. The information has been determined by the use of an electrical reservoir analyzer1, sometimes referred to as a Carter type analyzer. This instrument is an analog type computer which can be set up to represent a water-drive oil field. It can reproduce the past performance of the field in terms of analogous electrical quantities when the proper circuit analog of resistors and condensers has been determined, also, it can determine the future behavior for any method of production which may be selected, or permit the comparison among several different methods. Although most applications of the reservoir analyzer"" have been to thc study of specific field performance, it is intended to use the analyzer here to help understand how various reservoir characteristics effect the final performance of the field and to sec under what conditions water injection will be of benefit and to what extent. Within the oil industry the performance of water-drive reservoirs was first described analytically by LV. Hurst&apos; and M. Muskat2 for certain types of boundary conditions. The solutions of the equations developed involved products of exponential functions and Bessel functions. Later publications by Hurst4 and van Ever-clingen" and the hooks of Muskat6 gave further information on reservoirs with other boundary conditions. They also presented rather extensive curves and tables to help evaluate the analytical expressions involved. A rccent series of publications by Chatas. bascd on the work of Hurst and van Everdingen, gives quite complete charts and tables of data to evaluate the pressure decline or water influx in infinite or limited radial reservoirs. and in linear reservoirs. The curves in all of these publications are given in dimensionless form

Jan 1, 1956

By J. B. Dyess, H. A. Miley

Tarnish films on some of the common metals (particularly on copper and silver) have been of much scientific and commercial concern for a long time, but before the development of the electrical method1 of measuring film thicknesses there was no satisfactory quantitative approach by which to study the separate parts of these complex films. This method has been adapted to the measurement of duplex (cuprous-cupric) oxide films on copper.2 In the present work it has been used to measure tarnish films on copper when they were mixtures of cuprous oxide and cuprous sulphide, and also when they contained cuprous oxide, cupric oxide and cuprous sulphide, each component part being measured at a different potential value. Oxide-coated copper specimens, prepared by heating copper in air at chosen temperatures for given periods, were exposed to moist hydrogen sulphide in air to forml the various oxide-sulphide films studied. The comparative resistances afforded by (I) different thicknesses of oxide films, and also (2) equal thicknesses of oxide and sulphide films, against severe attacks of hydrogen sulphide were measured. The electrical method requires that the time be observed for the cathodic reduction of each part of the film substance, and these respective time values multiplied by the constant current give the corresponding quantities of electricity expended. Then each millicoulomb per square centimeter represents a film thickness of M X 108____ 2DX 96,494 X 103 where M is weight of oxide (or sulphide) giving one gram-atom of oxygen (or sulphur) for cathodic reduction, D is density of the oxide (or sulphide) and t is the thickness in Angstrom units per millicoulomb per square centimeter. The value of t for cuprous sulphide (cubical) is 14.27, and is obtained by substituting 5.78 for D and 159.20 for M in equation a. Previous values hf t for cuprous and cupric oxides (12.36 and 6.39, respectively) were used in the present work.

Jan 1, 1939

By J. B. Dyess, H. A. Miley

Tarnish films on some of the common metals (particularly on copper and silver) have been of much scientific and commercial concern for a long time, but before the development of the electrical method1 of measuring film thicknesses there was no satisfactory quantitative approach by which to study the separate parts of these complex films. This method has been adapted to the measurement of duplex (cuprous-cupric) oxide films on copper.2 In the present work it has been used to measure tarnish films on copper when they were mixtures of cuprous oxide and cuprous sulphide, and also when they contained cuprous oxide, cupric oxide and cuprous sulphide, each component part being measured at a different potential value. Oxide-coated copper specimens, prepared by heating copper in air at chosen temperatures for given periods, were exposed to moist hydrogen sulphide in air to forml the various oxide-sulphide films studied. The comparative resistances afforded by (I) different thicknesses of oxide films, and also (2) equal thicknesses of oxide and sulphide films, against severe attacks of hydrogen sulphide were measured. The electrical method requires that the time be observed for the cathodic reduction of each part of the film substance, and these respective time values multiplied by the constant current give the corresponding quantities of electricity expended. Then each millicoulomb per square centimeter represents a film thickness of M X 108____ 2DX 96,494 X 103 where M is weight of oxide (or sulphide) giving one gram-atom of oxygen (or sulphur) for cathodic reduction, D is density of the oxide (or sulphide) and t is the thickness in Angstrom units per millicoulomb per square centimeter. The value of t for cuprous sulphide (cubical) is 14.27, and is obtained by substituting 5.78 for D and 159.20 for M in equation a. Previous values hf t for cuprous and cupric oxides (12.36 and 6.39, respectively) were used in the present work.

Jan 1, 1939

By L. O. Howard

Much work has been done recently on the lead-antimony system1 in connection with lead-rich alloys of commercial importance containing less than 20 per cent. antimony. Dean, Zickrick and Nix have called attention to the perpetuation in the literature of several erroneous data, such as a eutectic temperature of 228° C. at 12.5 per cent. antimony, instead of 247° at 13 per cent. The series is given as a classic example of a straight eutectiferous series in such late books as those of Heyn and Grossmann, 2 Jeffries and Archer,3 Guillet and Portevin,4 Pulsifer,5 Rosenhain,6 and Liddell,&apos; as well as the somewhat earlier works of Hof-man (1918), Wang (1909), and Williams (1920). The work of Dean has definitely shown a solid solution of antimony in lead at about 2.5 per cent. antimony. While lecturing to a class in general metallurgy at the University of Idaho, the writer had the students prepare a series of lead-antimony alloys for the purpose of illustrating methods of thermal analysis. Proper proportions of powdered antimony (sold as C.P.) and test lead were mixed and melted in graphite crucibles under a reducing cover. Cooling

By William R. Rumbold

WHEN I was in South Africa during the latter part of 1904, there were three known tin-fields, which may be called the Cape Town, the Bushveld and the Swaziland fields. THE. CAPE TOWN TIN-FIELD. This district is situated near Kuils river, 20 miles west of Cape Town, and 5 miles from Kuils River station on the Cape Town & Stellenbosch Railway. The deposits are in granite, intrusive in the Malmesbury beds, which are supposed to be of Silurian or Cambrian age. The granite, resisting denudation better than the surrounding shales,, has formed low-lying hills, the highest of which, the Bottlelary Berg, is 1,510 ft. above sea-level. , The rock consists of quartz, orthoclase feldspar and biotite mica; tourmaline is also present. The feldspar occurs in large crystals. The rock is generally decomposed on the surface, and the decomposition sometimes extends as deep as 100 ft. This formation-granite intrusive in Silurian shales-extends for many miles to the northeast, but so far as I know the Kuils River deposits are the only ones now known to occur in it, though probably further prospecting will reveal other deposits. This particular discovery was accidental;. alluvial tin being found in the course of boring for oil. The Kuils River Deposit. This comprises both lode and alluvial tin. The lode strikes N. and S., and dips about 30° E. into the hill. It is 5 ft. wide, and composed of dense white quartz, in which pinkish-gray cassiterite is distributed in large crystals. The vein also contains considerable quantities of wolfram. Fig. 1 is a rough plan of the relative positions of the lode and the alluvial deposit, the latter, as shown, following the course of a stream, while the lode crops out on the hillside

Jan 7, 1908

By R. W. Woodward, G. K. Burgess

minum bronze. Nearly all copper-base alloys are improved by rolling processes, but the copper-aluminum alloys seem to possess equally good properties when cast or rolled; this is a remarkable metallurgical fact. Another important property of these copper-aluminum alloys is their resistance to alternating stress. Many tests indicate that their resistance is greater in this respect than that of some steels, and I have seen instances when cast aluminum-bronze bolts have outlived five steel bolts in foundation work subject to severe shocks. I mention these various instances to indicate that work originally started as research for substitution of one material for another frequently develops 212 article which has properties not possessed by the original metal or alloy. I have dwelt particularly on the aluminum bronzes because recently I have done more special work on them than on other alloys, but I believe that the use of aluminum itself, in many combinations of metals, is a very important subject for investigation. Undoubtedly, after the war, the cost of aluminum will be reduced from its present price, and considering its low specific gravity it offers a very interesting and important field for research in the non-ferrous business. Naturally, if combinations containing aluminum can be developed in view of a probably increasing supply of metal, the cost will be reduced. This will benefit the industry generally and will immediately conserve tin. Bronzes, Bearing Metals, and Solders G. K. Burgess* and R. W. Woodward,† Washington, D. C.— From a metallurgical standpoint, there are several ways in which a reduction of the tin consumed in commercial non-ferrous and white-metal alloys can be effected. First, a reduction of the tin content of the alloy; second, substitution of part or all of the tin content by some other metal; third, a substitution of a different type of alloy, which in some cases also involves a change in mechanical design. The Bureau of Standards has been studying these methods of conservation for tin alloys, particularly in regard to babbitts and bearing metals, bronzes, and solders. Much of the information sewed by the Bureau was obtained from answers to questionnaires sent to manufacturers and users of these materials, so that, in general, any of the following suggestions or recommendations can be considered as being practical and as having already been thoroughly tried. Bearing Metals There is no question that the tin content of nearly all bearing metals can be reduced to some extent, and in some cases actually eliminated

Jan 1, 1919

By F. B. Foley

With the possible exception of high-speed tool steel, the service demanded of rock-drill steel is probably more precarious than that of any other tool steel. Unaided by the helpful influence of alloys and dependent solely on the efficiency of the heat treatment applied for its ability to stand up under the abuse to which it is necessarily subjected, rock-drill steel is worthy of intensive study. For its heat treatment the smith has his fire, an oil fire perhaps, and a quenching bath; he judges the temperature by his eye. There are shops where excellent drills are produced by this method, but there are more where the product varies between very good and very bad. Pyrometers with specially designed equipment are used in but few cases. But the responsibility for rock-drill failures does not rest entirely on the smith. Little has been published concerning the efficiency of drill steel, though the Canadian Mining Journal1 published the breakage record of a large number of hollow drill steels. This record indicates that most of the breaks occur during the early life of the steel and that as a given batch of steel is used, its percentage of breakage decreases. This fact, the article points out, is at variance with the much-talked-of theory concerning failure from crystallization and fatigue. It seems to point to the fact that the greater part of drill-steel failure from breakage is traceable to faulty manufacture, resulting in defects in the bore of the hollow steel from inclusions of slag or oxides, etc. As this defective material meets with early failure, it is weeded out. In addition, some breakage may be caused by a lack of proper condition with respect to heat treatment of the steel as furnished by the manufacturer. In the article mentioned, the breakage of 1/14-in (3.17 cm.) hollow steel is given as 4.62 per cent. for the early period of use, with a decrease to 3.35 per cent. and 2.67 per cent. with time in use. For 1-in. (2.5 cm.) hexagonal hollow steel, the figures for breakage are 0.18 per cent. and 0.06 per cent.; attention is called to the great decrease in breakage by the use of smaller diameter drills. The figures are given as so many drills sharpened, but there is no way of determining the percentage of

Jan 1, 1922

By Timothy Collins

There was once a speculative period of interest in small mining companies that is commonly referred to as "the uranium boom of the 50&apos;s." In the late 60&apos;s, there was a second mining stock boom: it centered around uranium and silver, when silver had reached a new high of $3.60. In the mid 1970Js, there may be a new boom in the making, and it appears that substantial public and institutional interest in mining equities will finally result in a viable long-term capital market rather than the boom-or-bust pattern of the 50&apos;s and 60&apos;s. The reason for Wall Street&apos;s renewed interest in mining is understandable: most mineral commodities have recently gone up in price. Domestically, these price increases have come in the wake of the inflationary spiral unleashed by years of unbridled government deficit spending and erratic fiscal and monetary policies. Internationally, of course, the biggest push for higher prices has come from third-world countries whose primary income derives from indigenous natural resources. Many of these countries-whose fiscal and monetary policies haven&apos;t been models of excellence either-have attempted to cope with the worldwide economic mess by forming cartels that could control the price of commodities. What&apos;s happened to petroleum is well-known; what&apos;s happened to copper, bauxite, phosphate, and uranium is part and parcel of the same syndrome.

Jan 9, 1975

By Franz R. Dykstra

DEFINITIONS The ores of iron are classified in three general categories: direct shipping, concentrates, and agglomerated-i.e., pelletized or sintered. Direct Shipping As the name implies, direct-shipping ores are shipped as mined or, perhaps, after screening. Generally, direct-shipping ores are hematitic (R203), magnetitic (R304), or limonitic (2Fe2O3.3H20) in nature. Grades of direct-shipping ores vary widely. Prices are frequently related to the historical Mesabi standard of 51.5% iron, although certain premium lump ores may contain up to 68% iron. The use of direct-shipping ores is diminishing as the advantages of beneficiated ores become evident and reserves are depleted. Concentrates Where the nature of the deposit and economics allows, certain ores are upgraded. This may include no more than washing and screening, or may be as elaborate as fine grinding followed by magnetic, gravity, or even flotation procedures for separation. Coarser concentrates may be smelted "as is.&apos;; Fine concentrates usually are sold as sinter feed. (Sinter, as used here and in the following, refers to a process by which a fine ore-carbon mixture is agglomerated at elevated temperatures on a direct-fired moving grate to eliminate fines and improve chemical and physical homogeneity.) Agglomerates-Pellets or Sinter The development of economic techniques of mining and concentrating taconite (fine-grained, ferruginous jasperoids) led to the introduction of the iron-ore pellet, which is now becoming the major form in which iron is introduced into the furnace. The tremendous reserves of magnetic taconites of the northern United States and Canadian Precambrian shield had been recognized for many years. A century of mining has seen the reserves of the direct-shipping or "red ores" of the Minnesota, Michigan, and Wisconsin ranges approach depletion. Research started in the 1930s has seen the evolution of motives and techniques to concentrate these stubborn refractory ores. The efficacy of concentrate pellets in iron-making has been such as to induce mines throughout the world to grind, concentrate, and pelletize otherwise shipping-grade ores. Table 14.1A.1 shows typical analyses of iron ore. Marketing-Prices of iron may be quoted on a value per long-ton (2240 lbs) or metric-ton (1000 kg or 2204 lb) basis, or on a value per long-ton-unit or metric-ton-unit basis. One iron unit represents 1 % of contained iron per ton. (Thus, a price of $0.45 per iron unit for ore containing

Jan 1, 1976

RICHARD A. CONKLING (communication to the Secretary*).-Mr. Hager says that his results on the correlation of well logs in the north Cushing field are the opposite to those of the author. Can he, then, explain why the structural dip of the formations increases with depth, as Dr. Ohern, in his criticism, sets forth that it does, and as all who have worked in these fields will admit, if the shales thicken on the crest of the anticline, as he says they do? We are willing to agree with Dr. Ohern that there is some evidence of a slight unconformity below the Bartlesville sand and think that we can prove, from a specimen in our office, that .this unconformity comes at the base of the Bartlesville sand in the south Cushing pool. On the Ingalls dome, in the southeast corner of Township 19 North, Range 4 East, however, we get results the same as those given by the author on Cushing. The Ballard well in the center of the Northeast Quarter of Section 33 is just 10 ft. higher, structurally, according to tile, surface contour, than the Ringold well -in the center of the Southwest Quarter of Section 34. The dip in the Bartlesville sand, between these wells, is 40 ft. and the dip on the top of the Mississippi lime is 75 ft. This also might be accounted for, partly by the unconformity, but the author used the interval between the top of the Oswego lime, which is about 420 ft. above the Bartlesville sand, and the oil horizon found in the lime in the Ballard well-just mentioned above-to find the depth at which the same oil should be found in a well in Section 5, Township 22 North, Range 3 East, 25 miles North. Using this interval below the Oswego in the former well, we predicted within 2 ft. where they would find the oil in the latter well. Of course, we know that it was accidental that we missed it only by 2 ft., but if there were much of an unconformity in this interval it would be more of an accident if we came within 100 ft. of the depth. Since it can be proven from most of the structures in this section that the clip continues to increase downward, below the Bartlesville at least, to the Mississippi lime, it does not seem necessary to the author to try to prove otherwise that the depth at which the shales will tend to thicken on top of a fold, has not been reached above the

Jan 6, 1917

By J. A. Pusateri, M. A. Orehoski, N. R. Arant

Plant studies on commercial-size ingots and laboratory experiments with induction furnace heats have demonstrated that the major source of ingot cracks is associated with two conditions arising during top-pouring practice: 1—solidification during pouring, and 2—turbulence created by the impact of the stream. Methods of controlling the two factors were effective in eliminating or significantly reducing ingot cracks. BECAUSE the process of removing surface defects from hot-rolled product is so costly, the steel industry is striving constantly to develop methods of preventing, or at least decreasing, the occurrence of surface defects. Investigations have revealed steel-making and processing variables related to major surface defects, and controlling these variables has led to improvements in surface quality. However, the fundamental causes of major surface defects, such as ingot cracks, have not been determined; consequently such defects persist. At the Research and Development Laboratory of the United States Steel Corp. in Pittsburgh, a seam research program was initiated to determine the fundamental causes of certain major defects. As a part of the program, ingot cracks in killed, finegrained C1020 steel were selected for study. A cost survey indicated that, of the steels produced in sizable tonnages, carbon steels in the range of 0.18 to 0.23 pct C content require the most conditioning. Since this is particularly true of C1020, any im-provement of surface quality that might be effected from the study would be beneficial. Also, since the frequency of ingot cracks is exceedingly high for this grade, the steel would provide an excellent opportunity for a thorough study of the ingot-crack-ing problem. Why steels in this carbon range tend to exhibit more ingot cracks than do other steels was not considered in the investigation; the mechanism of ingot-crack formation was of paramount importance. Also, only the top-pouring practice was considered in the investigation, because this pouring procedure is used more extensively than others. In this study, ingot cracks are defined. as deep surface defects that sometimes are observed in an ingot prior to rolling but usually are observed during the initial stages of rolling on the primary mills. These defects may occur at any angle to the rolling direction but are most prominent in the transverse or nearly transverse direction. The appearance of ingot cracks on the rolled product varies with respect to their angle of formation and with the extent of rolling after their first occurrence. Ingot cracks are also termed "deep seams," "arrowheads," "irregular cracks," and "transverse cracks." Fig. 1 shows ingot cracks in a rolled bloom. This report summarizes: l—the exploratory investigation of commercial-size ingots; 2—the labor-atory investigations related to determining the source of ingot cracks and developing corrective methods; and 3—the plant evaluations of laboratory methods of decreasing ingot cracks. Exploration of lngot Cracks in Commercial Ingots Materials and Experimental Work: At the Du-quesne Works of the United States Steel Corp., five heats of killed, fine-grained C1020 steel were selected for the exploratory phase of the seam-research program. The heats were made by open-hearth practices that are considered most conducive to good surface quality. They were top-poured into 22x25 in. big-end-up hot-topped molds. One as-cast ingot and four other ingots rolled to the following cross-sectional sizes were set aside from each heat: 16x20 in.; 9 1/2x10 in.; 5x5 in.; and 2x2 in. The processing of the heats, from the time of charging in the open hearth furnaces to the end of the rolling operation on the primary mill, was observed carefully and recorded. The cast ingot and the four rolled ingots from each heat were examined for surface defects. The cast ingots were split longitudinally near the vertical center plane to expose the ingot structure beneath badly cracked regions. Also, a series of transverse sections was cut at about 1 in. intervals in a badly cracked area of one ingot. All sections were ground, polished, examined by sulphur printing and deep etching, and photographed. The rolled ingots

Jan 1, 1955

R. Trimble, Pittsburg, Pa (communication to the Secretary) : There are in the proposed specifications only two points on which I wish to comment at this time.

Jan 1, 1902

By Robert B. Fulton

Staurolite, an iron aluminum silicate mineral, is used industrially as the source of aluminum in portland cement manufacture in areas where the aluminum constituent is not economically available from shale or argillaceous limestone. It is also used as a high value- in-use sand blasting agent and as a premium grade foundry sand. It is produced by E. I. du Pont de Nemours & CO. as a coproduct in titanium mineral production in Florida where it was first recovered on a commercial scale in June 1952 from the Pleistocene sand deposit known as Trail Ridge. In the Trail Ridge deposit it comprises about 36 of the heavy minerals, the principal other heavy mineral constituents being ilmenite, leucoxene, rutile, zircon, kyanite, sillimanite, and tourmaline. Staurolite and the other silicate nonconductive heavy minerals are separated from the conductive titanium minerals on high-tension separators. The silicates are then separated from one another magnetically, the staurolite being relatively magnetic. In the total processing, 200 tons of raw sand yield 7 tons of heavy mineral concentrate from which about one ton of staurolite is recovered. Staurolite production is approximately 100,000 net tpy. No other commercial production of staurolite is known. This process yields staurolite concentrates of the characteristics given in [Table 1]. These concentrates are sold as three products with the size distribution of subrounded particles shown in Table 2. All three grades are used in sand-blasting for cleaning metal, for paint removal, and for cleaning buildings. Staurolite compares favorably with lower unit cost abrasives, such as boiler slags and mineral aggregates, in applications where the abrasive is used only one time and is not recovered. Because it is hard, fine, clean, and dense it can reduce blasting time, with less material reportedly being required

Jan 1, 1975

By John T. Norton, Matthew J. Donachie

Residual lattice strai?zs were produced in 2024 aluminum and ingot iron by uniaxial tensile deformation. These strains were rneasured on the original surface and ulith depth below the surface. The strains conformed approximately to those from a macroscopic stress distribution but they were not truly macroscopic in nature. The exact mechanism which apparently causes the coherently difi9,acting region of each grain to behave as if macroscopically stressed was not determined. MACROSCOPIC stresses in metals produce strains in the lattice which result in X-ray line broadening and line displacements. The latter effect can be utilized in a technique for determining stresses in metals as first shown by Lester and born.&apos; Subsequent advances in technique have enabled the X-ray method of stress measurement to be satisfactorily applied to many problems involving residual stresses of a macroscopic nature, such as those due to welding, grinding, shot-peening, and so forth. In the case of stresses such as those described above, the correlation of X-ray- and mechanically determined data has been generally good. However, plastically extended polycrystalline metals have sometimes been reported2 to show line displacements upon release of the applied tensile load, yet the nature or origin of the residual lattice strains, rls, producing these displacements has never been clear. As will be pointed out, this lack of clarity regarding the macroscopic or microscopic nature and origin of these stresses casts doubt on the validity of results achieved by the commonly accepted techniques of X-ray stress measurement. This anomalous behavior requires clarification to remove the doubts concerning X-ray stress measurement. The present paper is the result of an investigation of the interesting behavior of such plastically extended polycrystalline metal bodies. The studies were originated to carry out the following tasks: 1) Observe whether a residual lattice strain is produced as a result of plastic extension and show whether any residual lattice strains produced can be related to the usual concept of a macrostress. 2) Examine the origin of any residual lattice strains observed. 3) Consider the implications or consequences of the existence of such residual lattice strains on the problem of X-ray stress measurement. THEORY 1) Lattice Strains. The theoretical developments necessary for the treatment of lattice strains and their relation to stresses follow from the classical theory of elasticity and have been adequately covered by arrett. For an isotropic solid under homogeneous deformation, it can be shown that, for uniaxial stresses where Dl is the macrostress acting in the longitudinal direction; E$L is the lattice strain in the plane defined by the surface normal and the longitudinal direction at an angle, , from the surface normal; ET is the similar strain in the transverse plane; E is Young&apos;s modulus; and v is Poisson&apos;s ratio. Eq. [2] is independent of angle + and Eq. [I] is a linear function of sin2, see Fig. 1, and can be solved analytically for DL if E and u are known and EL is measured. Thus, a uniaxial macrostress will be indicated by a linear E,L vs sinZ plot and a

Jan 1, 1962

By Louis Ware

BEFORE the war we often heard the term "Big Business." And there were complaints of the ills and abuses attributed to bigness in business. Although there were examples where the small businessmen spoke for their rights and sought protection from the bigger ones, it has only been in recent war years that a tendency has developed definitely to divide the business of our nation into the big and the small. In some cases, those with an eye to the political value of the vastly greater number of small businessmen of the country have fomented this division by hurrying to the protection of these more numerous voters, and intentionally or not have emphasized in their writings and verbal attacks any and all differences of these interests that could either be found or fabricated to, suit the occasion. It has become another example of breaking the people into classes and thus setting up the basis for the claims of one class against another, and the subsequent demand for legislation and Governmental aid. The terms "big" and "small" are purely relative. One businessman, employing a hundred men, told me recently he did not know which adjective would be more appropriately applied to his operation. He did not know whether he should join the small operators&apos; group that had been organized, or should consider himself big. He said that his present plant seemed big to him when he looked back to its humble beginning many years ago with a couple of men in two rooms. Yet, when compared with many of his competitors who employ thousands, his was small. He did add, however, that he probably became big one day a few years ago when the union moved in and organized his employees.

Jan 1, 1945

By A. J. Boyer, T. R. Meadowcroft

An experimental determination has been made of the efject of surface diffusion on the vapor pressure obtained in a Kwudsen cell. The results show that a knife-edge orifice in a molybdenum lid may give erroneous results for the vapor pressure of silver. when a correction suggested by winterbottom and Hirth is made, the results become meaningful. Experimental work with cylindrical orifices in molyhdenz~m lids and knife-edge orifices in ceramic lids shows that good vapor-pressure results may he obtained when the orifice is designed so that ejfusion is the only significant source of weight loss. THE Knudsen effusion cell technique has been used by many investigators to study relative and absolute vapor pressures over metals and alloys at elevated temperatures. As a result of this interest, some theoretical studies have been made of geometric factors affecting effusion from the orifice of a Knudsen cell. A review of these studies has been made by Margrave.1 Recently, Winterbottom and Hirth2 have suggested that a physical effect, that of condensation, surface diffusion, and re-evaporation, may seriously affect Knudsen cell measurements, especially when a knife-edge orifice is used. Inasmuch as many of the present vapor-pressure data have been obtained using knife-edge orifices. it was felt that an experimental evaluation of the effect of surface diffusion on Knudsen cell measurements would be of value both in the design of the cell orifice and in establishing realistic estimates of the limits of error for existing data. The experimental program was in two sections. Firstly, measurements of the vapor pressure of silver were made in cells with cylindrical and conical orifices in which the surface-diffusion contribution to the weight loss should be negligible. These results were correlated with existing data to give a reliable measure of the real vapor pressure of silver. Secondly, measurements made using knife-edge orifices were corrected using the surface-diffusion theory of Winterbottom and Hirth2 and were then compared to the real values. The experimental arrangement is shown in Fig. 1. The balance was an Ainsworth RV-AU-1 automatic recording microbalance capable of measuring weight changes of ±0.02 mg on a total load of up to 100 g. The temperature was measured by an optical pyrometer signted on the bottom of the suspended crucible. The temperature readings were calibrated in a separate experiment in which pyrometer measurements were made while at the same time thermocouple readings were taken of the temperature at the inside top and bottom of the crucible. The range of reproducibility with this technique was ±4°C. A constant voltage source maintained a temperature of ±2°C at 1200°C over 10 hr. Silver of 99.99 pct purity was used in nonporous alumina crucibles. Lids of molybdenum, tantalum, or magnesia were cemented to the crucible using a sodium silicate cement. Table I shows the characteristics of the lids used. The vapor pressure is obtained using the basic Knudsen formula:

Jan 1, 1965