Search Documents

By Eugene A. Stephenson

Critical analyses of the work expended in producing oil by the utilization of gas energy have appeared in the publications of Shaw,' Pierce and LewisI2 and Herold,3 authors who have ably discussed the factors which must be taken into consideration in comparing energy consumed per barrel in various wells which are flowed by means of gas-lift. However, two distinct phases of oil production are concerned with the ratio of gas energy consumed to oil produced. One of these phases is the gas-lift, which utilizes the differential gas pressures for the purpose of flowing oil, whether these pressures be natural reservoir pressures or be induced by artificial compression of gas or air. The other phase has to do with prorating oil production in pools which are operated either as units, or are subject to such restrictions as those imposed at Oklahoma City by the Corporation Commission, or by similar controlling groups in other fields. An abundance of literature is available relative to the problems of flowing wells by gas-lift, but the first suggestion that the energy of the gas within the oil and gas pool might serve as a basis for proration, appeared in the timely article by Mc Williams.4 Much of the dissatisfaction with proration in certain fields arises because some operators feel that besides the hazard to the wells which accompanies the test, the method of allocating production on the basis of the " potential" gage is inequitable and gives some operators a distinct advantage over others.5 The most severe penalty may be exacted from the most progressive operators or those who attempt to produce their oil with a minimum quantity of reservoir gas. If no difficulties ever developed in drilling, shutting off water, or in well completion, it might

Jan 1, 1931

By John Burns

THE object of this chapter is to present data concerning the effect of the introduction of relatively slight amounts of carbon and nitrogen into supersaturated solution in iron. The study is confined to the alpha temperature range of both the Fe-C and Fe-N systems. The age-harden-ing characteristics of these two systems are considered. These data are compared to those of other age-hardening alloy systems and a "classifica-tion" is essayed. A.-RELATION OF LATTICE PARAMETER AND ELECTRICAL CONDUCTIVITY TO CHANGES IN PHYSICAL PROPERTIES DUE TO AGING OF FE-C ALLOYS Since Whiteley1 in 1927 showed that some of the iron carbide that is normally present in slowly cooled low carbon-iron alloys disappears on rapid cooling from just below the A1 point, interest has been manifested in the possibilities of age-hardening in these alloys. Masing and Koch,2 and at the same time and independently, W. Koster,3 proved these alloys to be age-hardenable. A. A. Bates4 a little later also published an interesting paper on changes in physical properties due to the aging of low-carbon steels. Many other papers have appeared showing changes in physical properties in specific instances due to this same phenomenon.

Jan 1, 1934

By AIME

THE wind howls almost incessantly over the mining engineers working in the near desert that is the Division of Namaqualand, the upper Atlantic coastal corner of South Africa's Cape of Good Hope Province. But when these men at the U. S.-owned mines called Nababeep South and East O'okiep (pronounced Oh-keep) tell you about their achievements, they can be heard above the wind. For their O'okiep Copper Co. Ltd. now produces over half the Union of South Africa's annual output of 30,000 tons of copper metal. Moreover, it is a very decent sample of U. S. geotechnical imagination. financial daring, and managerial skill, all operating successfully in a

Jan 1, 1947

By J. M. Morkowitr

A. Sawatzky (Atomic Energy of Canada, Ltd.)—The detailed criticism by Markowitz of my simple treatment of the thermal diffusion of hydrogen in Zircaloy-2 indicates that my paper was not as lucidly written as it could have been. I would therefore like to reiterate several of the main points of my proposed mechanism and describe in more detail some of the features only implied in the original paper. The distribution equation derived in my paper was stated to hold only for the case where the volume taken up by the hydride was small compared to the volume taken up by the solid solution phase, subsequent work, mentioned below, having shown it to be out by only a few percent up to a hydrogen concentration of about 3000 ppm. Of course, hydrogen in the two-phase region alone is not conserved in my treatment as pointed out by Markowitz. On the contrary, one of the important features of my proposed mechanism is that in the presence of a temperature gradient a two-phase region cannot exist over the whole specimen. For example, if the specimen is entirely a + 6 initially, then on application of a temperature gradient, a single phase (a) region at the hot surface develops from time t = 0 onwards. As mentioned in my original paper, the interface between the a and a+d regions moves toward the colder surface of the specimen with a discontinuity in hydrogen concen- tration developing at the interface and increasing with time. This interface moves at such a rate that hydrogen in the specimen as a whole is conserved. It must be pointed out that my distribution equation (Eq. [5] in Markowitz's paper) holds only for linear geometry. It is easy to show that for the cylindrical geometry of Markowitz the assumptions used in my treatment lead to

Jan 1, 1962

By R. L. Wiegel

The two questions considered in this study are: (1) what similarity is there in the liberation of magnetite from various iron formations, and (2) how is this liberation affected by the size reduction technique employed. Twelve sample suites were obtained from commercial concentrators processing magnetite iron formation in the United States, Canada, and Australia. These samples have grades in the range 15 to 45% magnetite iron and approximate mineral grain sizes o f 50 to 2000 microns. Efforts were directed at measuring the liberation characteristics of the samples obtained from the concentrators primary grinding mills. The Davis tube, a laboratory magnetic separator, was used to concentrate individual size fractions of the size reduction product to determine liberation data. These liberation data were compared with relationships calculated from a highly idealized mathematical model of liberation in a binary mineral system. The results of these comparisons have been encouraging for nine or ten of the twelve samples tested. This leads to the conclusion that for most commercial iron formations, at least with conventional rod mill size reduction, it is possible to quantitatively characterize liberation with two parameters: an effective mineral grain size and ore grade. Limited laboratory size reduction tests as well as one of two sets of liberation data from commercial primary autogenous grinding lend some support to the contention that autogenous grinding can affect mineral liberation.

Jan 1, 1976

By Arthur Wilson, Frederick Carr

INTRODUCTION 1. The application of retreat longwall mining to the North American coal mining conditions is becoming more advantageous as more experience is gained. The productivity results being achieved and potential possible illustrates that this system can be keystone of future underground coal production. 2. In the American coal fields multi-entry is normally practiced as this allows profitable longwall development with existing equipment and systems. Difficulties are being experienced however in the longwall retreat phase by the collapse of multi-entry roadways and excessive use of supplemental support in the following panel tailgates. In some instances the headgate of an operating face can also be in difficulty. 3. Jim Walter Resources Mining Division is developed on a mining plan that calls for three retreat longwalls at each of its four deep mines which have varying depths of cover and immediate roof and floor conditions. The 63 Mine has experienced longwall entry difficulty and there were differing viewpoints with respect to the best development systems to adopt particularily regarding the number of entries and pillar sizes. In an attempt to reconcile these different points of view J.W.R. asked Dr. Wilson to examine the problem and this paper outlines the new approach developed.

Jan 1, 1983

By Chase Palmer, Edson S. Bastin

While the reducing action of organic matter, of ferrous sulphate, and of hydrogen sulphide has frequently been invoked to account for the deposition of native gold and silver from ore-forming solutions, the high efficiency in this respect of certain of the metallic minerals which form the ore itself has not been suffciently recognized. If a little finely powdered chalcocite is placed in a test-tube arid 2 or 3 cc. of a dilute solution of gold chloride are poured over it, two or three shakes of the tube suffice to remove all the gold from the solution. The color of the solution changes from yellow to pale green, showing that copper is dissolved simultaneously with the precipitation of metallic gold. If a piece of chalcocite is hung in a dilute aqueous solution of silver sulphate (1/40 normal), a coating of silver begins immediately to form on the mineral, and within a few moments a beautiful silver tree has developed, similar to that formed when metallic zinc is immersed in a similar solution. When similar experiments are conducted with other sulphides and with certain arsenides and sulph-arsenides, especially those known to be commonly associated with native silver in ore deposits, it is found that these minerals differ greatly in their efficiency as precipitants, especially in their effect on silver solutions. The tests made with most of the minerals were qualitatipe only, but the reactions of a silver sulphate solution on chalcocite and niccolite were submitted to quantitative study to determine the nature of the reactions involved. Quantitative studies of the reactions with other minerals are now in progress

Jan 1, 1914

By J. A. Fulton

GOLD was discovered in the Sierra Nevada by J. W. Marshall on Jan. 2, 1848. The town: of Grass Valley soon sprang up and contained several stores in 1849; but the population of the town has always reflected the fluctuations in quartz mining. Gold-bearing quartz was found on Gold Hill in September 1850, and in the next two years most of the quartz bearing veins in the vicinity were located. At first, the quartz was crushed in mortars with spring poles; the Huff Co. took out $20,000 in this manner during the winter and spring of 1851. The first mill was put up in January, 1851. In 1866, there .were in Grass Valley 248 stamps, crushing 71,420 tons of ore with an average yield of $30 to $35; in Nevada City, there were 142 stamps, crushing 14,200, tons, with an average value of $25. But in 1918, only two properties in. this region, the Empire and the North Star, were producing. Since then, there has. been a revival of mining in the district and the following properties are being opened up: The Golden Center, Grass Valley Gold. Mines CO , Idaho-Maryland Mines Co., while the Sultana is kept unwatered and work is going on in a half dozen small properties.

Jan 2, 1926

By Wallace Ralston

The East Texas area includes the northeast 38 counties of the state of Texas. It covers all, and extends beyond, the borders of what is commonly described as the East Texas Basin. It is one of the most important oil and gas-producing areas of the Mid-Continent Province. It includes four important oil fields—Van, East Texas, Cayuga and Long Lake— and the recent extension of Rodessa field into Cass County, Texas, may prove to be of major size. Four commercial gas fields are in this area— Bethany, Waskom, Cayuga and Long Lake. Up to January, 1936, all of the oil has been produced from the Upper Cretaceous formations, and most of that from the basal member, the Woodbine sand. Gas is produced from both the Upper and Lower Cretaceous formations. Development in Fields East Texas Field.—This field continued to dominate the drilling and production situation throughout the United States. There were 4036 wells completed in this field during 1935; that is, 365 more wells than were completed during 1934. Drilling activity was due to close spacing of wells and the addition of 10,000 acres to the field. The field is now drilled to a density of one well to 6½ acres, which is certainly more wells than necessary for economic production of the field. The close spacing of wells is due mostly to the type of proration, which is per well allowable based on a potential test, and does not take acreage into consideration, and also to the numerous small acreage tracts such as town lots and excess strips. The field now has 19,519 producing wells. The allowable production for the field during 1935 was 161,118,659 bbl.; estimated production, including illegal or "hot oil," was 174,200,150. The illegal production of oil gradually decreased throughout the year, until an estimated low was reached of 20,500 bbl. daily during the months of November and December. The price of oil remained at $1.00 per barrel throughout the year. As stated, about 10,000 acres were added to the field during the year, making a total of 128,000 productive acres. There is a possibility that

Jan 1, 1936

By John Blatchford, William T. Hall

The product obtained by roasting stibnite is likely to contain some unoxidized antimony trisulphide and a mixture of antimony trioxide and antimony tetroxide. It was desired to determine, as accurately as possible, the condition of the antimony as well as the total quantity present. Attempts were made to separate the trisulphide and the two oxides by methods based upon their varying solubilities in different solvents, but no satisfactory results were obtained in this way. It was found, however, that by determining the total antimony content, the antimony present as trioxide, and the antimony present as trisulphide, a good idea of the chemical composition of the roasted product could be obtained. The total antimony was determined by dissolving the sample in concentrated hydrochloric acid, reducing the antimony entirely to the trivalent condition by means of hydriodic acid and eventually titrating the antimony back to the pentavalent condition by means of iodine in the presence of sodium bicarbonate1* The details of the procedure are as follows: Weigh out 0.25 gram of the roasted product into a trapped flask (Fig. I), add 4 grams of powdered tartaric acid, 2 grams of potassium iodide and 40 c.c. of concentrated hydrochloric acid. Boil the solution gently f;r 5 min. and then cool to room temperature by shaking the flask while holding it under running water. Then, very carefully discharge the iodine color by the cautious addition of 0.05-normal sodium thiosulphate solution, adding a little starch toward the last. Nearly neutralize the acid with ammonia solution, but leave the solution distinctly acid. Pour the slightly acid solution into 200 c. c. of water containing an excess of sodium bicarbonate and titrate to a permanent blue color with standard 0.1-normal iodine solution.

Jan 1, 1916

By Marston G. Fleming

E. C. Peterson (Anaconda Copper Mining CO., Darwin, Calif.)—A study of this quite comprehensible and interesting paper by Dr. Fleming brings to mind several observations in the practical application of alkalinity and related factors to the actual practice of lead mineral flotation. Soda ash has long been a widely used and a very helpful alkaline conditioning agent in the flotation of galena from the usual run of lead-zinc ores. Soda ash is one of the common "standard" conditioning agents tried in any laboratory investigation of lead-zinc ores because it has so often proved helpful to galena flotation. However, the use of soda ash in the actual flotation of oxidized lead ores is certainly not widespread. In the flotation of certain lead-zinc ores from the Park City district of Utah, it was found in the usual cyanide-zinc sulphate-xanthate circuit that soda ash had an effect of producing a very condensed and flat froth regardless of the many frothers tried and that substitution of lime for soda ash to produce the same pH (8.0 to 8.4) improved the froth condition. However, the flotation of coarse particles of galena became so critical that some would pass through into the tailing, but caustic soda as a substitute for either soda ash or lime produced a very desirable froth condition in the same pH range and greatly improved the metallurgical outcome. Milling was carried out in typically "hard water" from watersheds of limestone and other calcareous rocks and the ore also apparently contributed magnesium and calcium salts to the pulp. Certain lead-zinc ores of Mexico have shown their greatest flotation response in circuits conditioned with sodium bicarbonate, and such actual mill use was also believed to be related to the water necessarily used in milling. On other lead-zinc ores the optimum has been obtained in actual milling treatment by use of caustic soda in both circuits of the operation. In flotation of oxidized lead ores in which sulphidi-zation is employed by addition of sodium sulphide, very high pH's exist in the flotation circuit. With the usual oxide lead ores, demanding 5 to 15 lb of sodium sulphide per ton of ore, pH's in the circuit (closed and open water-circuits) may range from 9.5 to 12, and for ores that contain much anglesite or a high percentage of iron oxide minerals, sodium sulphide consumption may reach as much as 30 lb per ton of ore and the resultant pH will be correspondingly higher. Yet in such flotation treatment employing either xanthate or oil (high-sulphur crude oil or diesel oils) as the collector, satisfactory to excellent grades of concentrate and lead recovery are obtained. Although there have been great studies and accomplishments in the investigations of flotation fundamentals and flotation theory, and although an investigation to determine the effect of all factors entering into the actual plant flotation of sulphide and oxide ores must become very complicated, as Mr. Fleming has mentioned in his caution regarding the drawing of general conclusions for other ores, it seems that it would be of greater interest if the techniques and investigations could, with time, approach the conditions of actual practice and lead the way to improved and more efficient flotation plant performance. Marston G. Fleming (author's reply)—The gulf between fundamental flotation research and plant operation is, perhaps, less wide than Mr. Peterson suggests. For example, the work described in my paper developed from an extensive investigation of a complex lead-vanadium ore from southwest Africa. This investigation started as a standard ore-testing problem but, at almost every stage, results were obtained which could not be interpreted in terms of previous experience. A program of fundamental research was therefore undertaken and was closely interlocked with the ore testing. This coordinated investigation resulted in a flotation process which has now been proved by two years of successful plant operation, and although the grade and mineralogical constitution of ore as well as smelter requirements have altered more than could have been anticipated, our knowledge of the fundamental character of the problem has made it possible to meet each change in conditions with much more confidence than would have been the case had we neglected this aspect of the investigation.

Jan 1, 1954

By W. A. Dunkley, W. W. Odell

The sulfur content of coal is perhaps more important in the manufacture of illuminating gas than in any other coal-using industry. Whether the gas is made by the distillation of coal in retorts or ovens or by steaming incandescent coal or coke in the water-gas process, a portion of the sulfur present in the fuel always passes into the crude gas. Practically all the sulfur that remains in the finished gas is transformed into sulfur dioxide (SO2) when the gas is burned. Sulfur dioxide is a pungent suffocating gas and, if present in the air in any perceptible amount, is deleterious to health and comfort and damaging to house furnishings. SO universally is this recognized that laws regulating the amount of sulfur that may be permitted to remain in the gas are very generally in force. The capacity of a plant to purify gas frequently limits the selection of coal for gas making. This condition may arise from different causes. Some plants were originally designed to handle a certain grade of low-sulfur gas coal, and very little leeway was allowed for growth or for the use of inferior coals. Other plants, when built, had ample capacity to purify gas from relatively higher sulfur coals, but their output has grown so rapidly that their purifying capacity is now limited and only the low-sulfur coals can be handled. There is a great quantity of coal in the United States that would satisfy the requirements of the gas manufacturer, were it not for the high sulfur content. The coals containing less than 1 per cent. sulfur are becoming scarcer year by year and, in time, the gas industry will probably be compelled to use coals that are now considered out of the question. Sulfur Compounds in CRude Gas Sulfur exists in unpurified illuminating gas in a variety of compounds; chief of these are hydrogen sulfide (H2S) and carbon disulfide (CS2). In crude coal gas H2S is usually present to the extent of 0.5 to 2.0 per cent., by volume, equivalent to about 300 to 1200 gr. per 100 cu. ft. of gas. In carbureted water gas, the amount of sulfur compounds depends not only on the sulfur content of the coal or coke used, but also upon cite

Jan 1, 1920

By A. C. Fieldner

THE total annual energy production from coal, petroleum, natural gas and water power has been increasing at a fairly constant rate during the thirty years ending in 1930. But since 1913 the demand for the competitors of coal has increased at a rate faster than that for coal. During the last twenty years, the curve of coal production has had a generally horizontal trend; in fact, the 1930 production of coal was six per cent less than that of 1913. Economists attribute this loss of demand to greater efficiency in coal utilization and to displacement of coal by oil and natural gas. These two factors are about equally responsible, and it is evident that research has been intimately concerned with both. About sixty per cent of the bituminous coal mined in the United States in 1929 was used for generating steam, either in stationary or locomotive boilers. A decade ago seventy per cent or more was used for this purpose. This change is due largely to tremendous advances in fuel economy.

Jan 1, 1933

By AIME

IRWIN W. ALCORN, present Chairman of the Petroleum Division, was born Sept. 5, 1899 at Marietta, Ohio, and moved with his family to Robinson, Ill., at the time of the early oil development there. This was in the days of the Star spudders, mud, mules, and Stanley steamers. Al graduated from Robinson High School after participation in basket ball, also attaining the captaincy of the football team of that school. He entered Missouri School of Mines and Metallurgy in 1918 and was ushered by the Army into the S.A.T.C. In 1920 he transferred to the Massachusetts Institute of Technology, later to return to receive his B.S. degree -in metallurgy at Rolla, also joining the AIME. On graduation, he worked for the Skelly Oil Co. at Cushing, Okla., shifting to the Moore Refining Co. at DeNoya, Okla., as superintendent of a small pipe-line system. After an interval of two years with the National Supply Co. in Tulsa, he joined the Independent Oil and Gas Co. of that city, and at various times was chief engineer of the Texas division, superintendent of the West Texas pipe-line system, chief engineer of pipe-line construction, and chief engineer of the refining division. Al organized the Company's production engineering department. In 1930 the Company was merged with the Phillips Petroleum Co. The depression was in and Al was out, 'as was true nine months later when the Smith Separator Co. whose chief engineer he had become, was liquidated. The next few years was spent with Oil Well Supply Co. as a subsurface pumping equipment engineer

Jan 1, 1948

Established as a Division March 24, 1922 John R McMillan, '56, Chairman Claude R Hocott, '55, Past Chairman Thomas C Frick, '56, Vice-Chairman D W Akins, '57, Vice-Chairman Joe B Alford, Executive Secretary 800 Fidelity Union Building Dallas 1, Texas T A Pollard, Treasurer

Jan 1, 1954

By L. W. WALLACE

IN an engineering fashion we have made an assay of the engineering profession, using as a. sample the engineers listed in "Who's Who in America" (1928-1929). We are aware that some will say it is an unfair sample; that it came from the best mine. This is readily admitted, with this qualification: that all engineers and architects by virtue of their training and experience have been freed of most of the dross to which mankind is heir. They are -a selected group to begin with, having all the potentialities those in the sample possess. We are also aware that some will say a part of those included in the sample are not engineers. Our answer to that criticism is this: An engineer is no less an engineer because for the time being he is president of a bank, a university, an opera company, or a hotel company. Moreover, he is no less an engineer because he is a governor of a commonwealth, a United States senator, a member of the Cabinet, or the President of the United States.

Jan 1, 1929

By H. F. Moore

We have studied the simple case of repeated stress, without considering impact, which might bring in other factors. This investigation has shown that steel under repeated applications of stress, reversed from positive to negative, will not fail below some fairly clearly defined limiting stress that, so far we can see, does not bear any definite relation to the ordinary elastic limit, being as large as the elastic limit in some cases and about one-half the elastic limit in others. According to one theory, fatigue is the result of changes in crystalline structure by repeated stress. I do not know of any evidence in favor of this theory. The crystals are broken under repeated stress. According to Bauschinger, under repeated stress some inherent property of the material changes its elastic limit; possibly some property of the amorphous cement between the crystals. A third theory is that all fatigue of metals is the result of the spread of damage from little localized overstresses. While I do not feel justified in accepting the last theory rather than the second, I have yet to run across a case of failure of steel or other metal, either in the laboratory or in service, that could not be explained by the gradual spread of damage from some nucleus. We have found, for example, that it is possible to subject a homogeneous steel, like Armco iron or a 0.90 per cent. carbon steel, that has been thoroughly annealed, to one hundred million reversals of stress as high as the elastic limit of the steel with no sign of failure. On the other hand, a complex structured steel, like a chrome-nickel steel that has been hardened with very little drawing, will fail at a stress about 58 per cent. of its elastic limit. Between these two we get a variety of results. In the steel work of any building, there are undoubtedly many thousands of places where structural damage was done—where riveted members were bent into place cold and where the rivets were fitted with drift pins, etc. Locally the steel in the building was stressed beyond its yield point in many places. These little localized overstresses do no damage at all; the building is entirely safe. But if this building were subjected eight or ten times a day to a mild earthquake, these little localized overstresses might be nuclei from which damage would spread

Jan 1, 1922

By D. O. Hobson, P. L. Rittenhouse

We have recently found that many lots of Zircaloy-2 and -4 tubing tested in tension deform to cross section shapes that are "polyhedral" rather than circular. The noncircular cross sections seem to result from a circumferential variation in plastic proper -ties and, therefore, in texture. We examined the diffracted X-ray intensity from (OOOl), {1010), {ll20}, and {1011} planes parallel to the tubing surface around the entire circumference. Tubing that deformed to a circular cross section showed <5 pct variation in diffraction intensity around the circumference from any of these planes. Greater intensity variations were found for all the tubing materials that developed non-circular cross sections during deformation. In each instance the number of intensity maxima and minima was consistent with the number of sides of the &apos;polyhedral" cross section. THE effects of crystallographic texture on the mechanical properties of zirconium, zirconium alloys, and other anisotropic hexagonal materials such as titanium and hafnium have been intensively studied. If the natural crystallographic anisotropy of these materials could be controlled by selected fabrication operations, a material could be produced with a texture, or preferred orientation, in which the maximum strength directions are in the stress directions of the structure. The permissible stress levels of the structure could then be increased. Rittenhouse and Pickle-simerl have shown that highly textured Zircaloy-2 plate can vary from 52,000 to 70,000 psi in tensile yield and from 62,700 to 122,000 psi in compressive yield strengths as a function of specimen orientation. Similar texture effects have been observed in Zircaloy tubing, whose mechanical properties differ depending upon whether the tubing has basal poles predominantly radial or tangential and upon the mode of testing. These same texture effects might be troublesome if the texture in the tubing is not uniform around the tube walls. This paper is concerned with the effects of nonuniform texture on the strain behavior of commercial Zircaloy tubing. BACKGROUND Previously, various lots of commercial Zircaloy tubing were tested under selected stress conditions as part of a program to determine the four quadrants of the yield locus. One of the testing procedures was uniaxial tension and it is the influence of texture variations on the tensile deformation behavior of the tubing that is of interest here. The effect of texture on the strain behavior in tubing is very apparent from a uni-axial tensile test.2 This behavior is illustrated schematically in Fig. 1 for three different tubing textures: 1) basal poles predominantly in the radial direction; 2) basal poles predominantly in the tangential direction, and 3) basal poles equally distributed between the radial and tangential directions. In the first example most of the grains are oriented for prism slip to operate to allow axial lengthening and diametral reduction of the tube. Reduction in wall thickness requires {1122} twinning, a more difficult operation than slip.* In the second example, the texture is such that *The singleCrystal analogy will be used quite often in this paper when strong texturesare being discussed. The textured material is assumed to react as if it were a single crystal aligned in the same orientation and under the same stress system as the predominant texture._____________________________________________ prism slip operates to give axial lengthening and wall thinning. Diametral reduction requires twinning and again should be more difficult to accomplish. A specimen with basal poles equally distributed between the radial and tangential directions should exhibit about equal diametral and wall strains.* Table I shows the *Diametral strain is accomplished by a combination of circumferential and longitudinal strains. But, for the purposes of this paper, it will be considered as a strain causing a change in the length of a specified diameter.__________ strain behavior of two lots of tubing with different textures. The first tube has a texture with basal poles equally distributed between the radial and the tangential directions. The ratio of true thickness strain to true diametral strain is almost unity. The second tube has a predominantly radial basal pole texture and it is apparent that most of the total strain has occurred by diameter reduction, just as one would predict. There is over three times as much diametral strain as thickness strain. RESULTS We found that specimens from certain lots of commercially fabricated tubing did not retain round cross sections during uniaxial testing. Instead, the speci-

Jan 1, 1970

By F. R. Hensel

THE alloy under discussion is a nickel-silicon bronze and is one of many age-hardening or precipitation-hardening FIG. I.-EFFECT OF QUENCHING AND AGING TEMPERATURES ON HARDNESS OF TWO TYPICAL NICKEL-SILICON BRONZES, NO. 2351 AND No. 2362. copper-base alloys. The hardening con-stituent is a nickel-silicon compound.1 The quenching temperature necessary to pro-duce hardening by a subsequent aging treatment is a function of the composition and extends from about 700&apos;C. to ()50&apos;C.; the aging temperature range extends from 400° to 600°C. The work carried out by the authors of this paper was confined to cast alloys having compositions within the ranges of 1.5 to 3.00 per cent Ni; 0.4 to 0.75 per cent Si; balance, copper.

Jan 1, 1940

By R. W. Fountain, John Chipman

The solubility of nitrogen in Fe-B alloys (0.001 to 0.91 pet B) is determined by the Sieverts&apos; technique for temperatures of 950° to 1150°C. The activity coefficient of nitrogen is decreased by boron. The three-phase equilibrium between ? iron, BN, and gas is established and also the four-phase equilibrium between iron, BN, Fe2B, and gas. The above equilibria are calculated for a iron. The relation of these data to hardenability and strain aging of boron-treated steels is discussed. BORON additions are known to enhanbe the hardenability of heat-treatable steels and to assist in the control of strain aging in sheet steel for deep drawing. The increase in hardenability is explained by the theory that adsorption of boron on austenite grain boundaries reduces their free energy and thus retards ferrite and upper bainite nucleation.l,2 Digges and Reinhart3 have shown that the full effectiveness of boron in commercial steels is achieved only when strong nitride formers such as titanium and zirconium are also present. The influence of nitrogen on eliminating the boron contribution to hardenability was also demonstrated by Shyne and Morgan.4 These workers prepared Ni-Mo steels containing either nitrogen or boron or nitrogen plus boron. The nitrogen-plus-boron steels showed the lowest hardenability which was attributed to the presence of stable nucleating particles, presumably nitride. Morgan and Shyne5-7 have shown that boron in the amount of 0.007 pet will completely eliminate strain aging due to nitrogen in low-carbon, open-hearth steels. In addition, by proper control of the boron additions, a rimming steel can be produced. Since the effectiveness of boron on hardenability and eliminating strain aging is influenced by the amount and distribution of the nitrogen in the steel, the present study was. undertaken to determine the influence of boron on the solubility of nitrogen in iron. EXPERIMENTAL PROCEDURE The solubility of nitrogen in Fe-B alloys was measured by the method of Sieverts, which consists of determining the amount of gas dissolved by the metal in a constant volume system. The apparatus employed in this investigation and the experimental details have beendescribed previously.B AMcLeodgage was added to the apparatus to allow measurements at very low pressures. The alloys were melted at reduced pressure in a basic-lined induction furnace using electrolytic iron and ferroboron. Ferroboron was added after the primary deoxidation of the iron with carbon. Since it was difficult to attain a constant low level of oxygen by this procedure, silicon was added after the carbon deoxidation and prior to the ferr obor on addition. The alloys were castas 2-in. sq ingots, heated in argon at 1050loC, and forged to 1/4-in. plate. After forging, 1116 in. was machined from each side of the plate to remove any possible contamination, and it was then cold-rolled to 0.010-in. sheet. The sheet was cut into approximately 1/4-in. squares and pickled in an inhibited H2SO4 solution to ensure a clean surface. In the case of the boron alloys, a hydrogen treatment could not be used for surface cleaning because boron losses resulted. The composition of the alloys is given in Table I. For a solubility determination, a 75-g sample was inserted in a quartz tube and sealed in place in the apparatus. The entire system was evacuated at room temperature and leak tested for 24 hr. If no leaks were observed, the system was heated to the temperature of measurement and again leak tested for 24 hr. If no leaks were detected, the hot volume and solubility determinations were begun. The hot volume was determined at a constant temperature for each run by admitting successive amounts of argon and recording pressure vs volume, which, in all cases, resulted in a straightline relationship. The argon was then removed and the procedure repeated with nitrogen. Successive additions were made until the desired nitrogen content of the metal and equilibrium pressure of the system were obtained. The

Jan 1, 1962