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By C. K. Ferguson, J. A. Klotz

This paper describes experimental investigations conducted at the California Research Corporation's model oil well. The first part describes filter loss from several drilling muds through bore hole walls during mud circulation and drill string rotation. The effect of mud properties and drill string rotation with mud circulation is described. Filtration from a bore hole full of drilling mud, not circulating, but under pressure for extended time periods, is also discussed. The second part describes filter loss to permeable formations from beneath a drilling bit where filter cuke has no opportunity to develop appreciable thickness. If potential flow theory is applied to predict filtrate invasion from this hole bottom, targe invasions arc calculated. But model well experimentation shows that filtrate invasion from the hole bottom is controlled by mud particles that penetrate the formation ahead of the bit. This experimentation provides data to estimate the effect of mud particle penetration on fluid loss to formation. The third part presents an estimate of mud filtration during drilling of a well. INTRODUCTION As oil wells are drilled by the rotary method, drilling mud circulates up the annulus between drill pine and well wall. Drillers adjust mud density so that the pressure at the bottom of the mud column is several hundred psi greater than the pressure of reservoir fluid. As a result of this pressure difference, the liquid part of the mud filters into the rock around the bore and mud solids deposit as a filter cake on the well wall. For many reasons the petrogleum industry, within the past 20 years, has spent much money and energy to determine the volume of mud filtrate that enters rock around the well bore and dedicated much research effort to reduce this volume. Among the reasons for attempts to determine the volume of mud filtrate and to reduce this volume are the following: 1. If filtrate damages the permeability of oil sand, the resultant damage to oil well productivity will depend on the distance that the filtrate invades the oil sand; reduction of filtrate volume may, therefore, increase well productivity. 2. Filtrate that penetrates shale sections may cause the shale to swell and to slough into the well bore. Uncontrolled sloughing may stick drill pipe. Reduction in filtrate volume may reduce drilling trouble. 3. Electric log resistivity curves are changed by invasion of a mud filtrate; the change depends on the depth to which filtrate invades. Knowledge of this depth is necessary before resistivity logs can be interpreted accurately. For these reasons, specifications the place an upper limit to drilling mud filter loss are now written into almost all drilling programs. These specifications are based on APT Recommended practice 29, Standard Field Procedure for Testing Drilling Fluids,' which describes a static filtration test operated at 100 psi filtration pressure and at ambient temperature. Although this test is adequate for mud control, it cannot be used to compare filtration properties of different muds. Schremp and Johnson' showed, for example, that mud with a low API filter loss does not necessarily have low filter loss at bottom hole temperature and pressure. Also, no information has been available about the effect of bottom hole mechanics (mild circulation, drill string rotation, and bit action) on mud filtration. This paper discusses filtration data measured in the California Research Corporation's model oil well, which models closely oil well bottom hole geometry and hydrodynamic conditions. The filtration processes that

Jan 1, 1955

By Wayne P. Myers

Electricity, as normally thought of by a layman's definition, is a manmade force that has no color, no odor, is not visible, cannot be heard, yet man can control it and make it perform his work for him. A person dare not cheat on it, for it then will master him. It has laws, rules, and regulations that must be strictly adhered to if it is to perform in the safest, most reliable, and economical manner. In the early days of coal mining the power source was man himself. Later man employed steam and compressed air to reduce his muscle power requirements needed in the extraction of coal. By the turn of the 20th century, electricity had become the most common source of power for the coal industry. Steam and compressed air are still found in use in isolated cases today for specific applications; however, they are rapidly being replaced by electricity. Electrical laws and regulations are quite extensive and somewhat complex for the proper generation and use of electricity. Man-made laws, rules, and regulations for the care and handling of electricity, designed for man's safety, are rigidly enforced by the U.S. Bureau of Mines, as well as the various state departments of mines. BACKGROUND Until recent years most underground coal mines used direct current exclusively for all movable and for some stationary equipment. Exceptions were for permanent pumps, tipple, fan, and outside buildings where alternating current was normally employed. However, over 60 years ago there were mines with dual systems. Alternating current was used for cutting machines, drills, and pumps, direct current for locomotives. There were no other machines as these were hand-loading mines. Later, during early mechanization in the 1920s, alternating current was also applied to loading machines at some mines. Use of dual electric systems then declined until fairly recently when

Jan 1, 1973

By B. E. Cornish

Most technical and statistical data published on pyrophyllite relating to production figures, uses, markets and sales, have in the past traditionally linked the mineral with talc and soapstone. This is due to several common superficial physical properties resulting in substitute uses and applications. However, these minerals are not similar in chemical composition and do not generally occur in a similar geological environment. Pyrophyllite now stands on its own in the marketplace-particularly in ceramic applications-due to the combination of excellent heat shock and creep resistance properties of the mineral. The increase in pyrophyllite use in the field of ceramics indicates the continuing realization of these marked unique properties. Several new fields of ceramic applications, previously the preserve of high-alumina materials, have been developed on the intrinsic properties of pyrophyllite. Pyrophyllite is an aluminum silicate with the molecular formula of AI2O34SiO2H2O. It would be more appropriate to group pyrophyllite with such materials as kyanite, diaspore, andalusite, and certain high-alumina clays in relation to its general applications (Stuckey, 1928). These materials all have good beat shock resistance properties at high temperatures and are widely used for the manufacture of refractories. For those reasons they are interchangeable in some applications. Pyrophyllite also has many uses in nonceramic applications, the most important to date being as a substitute for talc in fillers. The major pyrophyllite mining operations are located in the US, Japan, Korea, Canada, and Australia, where the mineral is widely used as a raw material for general ceramic, mineral filler, and dilutant applications. Commercial Applications Pyrophyllite was first used in the last century for lining stoves and fireplaces, and also in the carving and polishing of ornamental objects. The rise in industrial demand for new products and applications resulted in the introduction of pyrophyllite as an alternative, mainly for talc and soapstone. Industrial filler applications followed for paint, paper, cosmetics, rubber, pesticides, crayons and pencils, and bleaching soap. The first use of pyrophyllite in ceramic applications was prior to World War II, in the manufacture of ceramic cladding tiles in the US. This was followed by the production of kiln furniture refractories and whiteware when pyrophyllite was offered by suppliers in North Carolina as an alternative to some local clays. The largest tonnages of pyrophyllite used today are in refractory linings in steel ladles in Japan, as seen in Table 1. The consumption of pyrophyllite in Japan is second only to clay and chamotte among refractory raw materials used. Recently this technology has been adopted in Australia. Japanese and Australian practice has resulted in appreciable technical and economic benefits, particularly when pyrophyllite is used in combination with zircon. The potential growth for this application is substantial if US and European steelmakers follow. Investigation and research into the properties of pyrophyllite determined the following main advantages of pyrophyllite-based ceramics: high corrosion resistance for molten iron, steel, and slags; good heat shock resistance; good indices of deformation under load and hot creep resistance (refractories); and increase in mechanical strength of whiteware products promoted by a better distribution of mullite in finished products (also obtained at lower firing temperatures than normally required in production of triaxial ceramics). White cement

Jan 1, 1983

By J. R. Long, E. T. Hayes, D. C. Root, R. S. Dean

THE U. S. Bureau of Mines has recently reported on the development of a process for preparing pure ductile titanium in substantial quantities' and on the physical properties that may be attained in the metal, when consolidated by powder metallurgy methods and fabricated by certain hot and cold-working procedures.2 The high physical properties (Table I), combined with excellent corrosion resistance and light weight, will lead no doubt to appropriate applications of the metal. In any application, methods of joining will be of considerable importance. The relatively high activity of the metal toward the common gases raises the question of weldability and conditions that might be required for successful welding. Since hydrogen, oxygen, and nitrogen embrittle the metal, it should be protected from these gases at elevated temperatures. This was demonstrated by a few preliminary trials of arc, gas, and resistance welding. In these trials only the resistance method proved to be immediately applicable. While atomic hydrogen welding of titanium may be successful in some instances, a considerable amount of development work will be required to prove its worth. In addition, it would be suited only to small assemblies that could be heated subsequently in a high vacuum to remove embrittling hydrogen. Heli-arc methods likewise would be limited to small assemblies, which could be completely protected by a helium atmosphere. It was quite apparent that titanium required more protection than was afforded by the normal flow of helium gas used for welding magnesium and aluminum. The hot metal is attacked by oxygen and nitrogen, and the rapid diffusion of the oxide into the metal prevents the formation of a protective coating and requires the helium atmosphere to be maintained until the weld has cooled nearly to room temperature. The preliminary work indicated that titanium could be successfully spot-welded without deterioration of the metal and that the microstructures of the welds were normal, exhibiting good bonding, and no oxidation. The high resistivity of titanium (53 microhms per cu. cm.) suggested that it would behave somewhat like stainless steel and allow considerable latitude in the several welding variables. The results reported here are intended to give a general picture of the effects of varying welding current, welding time, and tip pressure on single spot welds made on several different thicknesses of titanium sheet. The work was undertaken to demonstrate the feasibility of welding titanium rather than as an exhaustive study of spot welding. There are, therefore, a number of factors that will require further investigation to establish the specific controls required for actual applications.

Jan 1, 1946

Discussion of the paper of John H. Hall, presented at the New York. Meeting, October, 1913, and printed in Bulletin No. 79, July, 1913, pp. 1247 to 1256. WILLIAM 'R. WEBSTER, Philadelphia, Pa.:-I would like to call ,attention to the fact that the results of the ordinary tension and bend tests do not always give us the information we want even if we figure out the amount of work done. You want a bending test of sufficient width and full thickness. In the case of eyebars, for instance, I have had experience with a 10- by 1-in. eyebar which gave perfectly good results in a full-size test of the finished bar. The 10- by 1.5-in. and 10- by 1.75-in. eyebars from the same heats-of steel were absolutely worthless in full-size tests. The narrow bending tests from all these bars gave good results. Bat after going into the matter fully, we found that if pieces about 3 in. wide and full thickness were used for the. cold bending tests, the heavier material would not stand this test, but failed. That is, in order to check the quality of the rolled bar you should have a wide piece of full thickness for cold bending, as the narrow pieces give misleading results. J. E. JOHNSON, JR., New York, N. Y. :-I would like to ask if there have been any tests made to compare the results of Charpy tests with the true dynamic test similar .to the Wohler test, except that the piece is subjected to a tensile or compressive stress and to alternating stresses in addition, at the same time. This seems to me to approach more nearly than any other test to the conditions of actual service. where the piece is under a fixed initial stress plus a highly variable and often alternating stress. Some tests were made on this plan in England within a year or two. The test piece was Subjected to either a tensile or compressive stress of known amount and simultaneously to alternating stresses in addition. Such a. test as this gives information which we cannot get by a tensile test or even from the tensile strength multiplied by an. elongation. Such tests, however, are exceedingly tedious and require long periods of time in order to obtain valuable results. If material could be subjected to these dynamic tests and the same material to the. Charpy shock test, and if some reasonable qualitative relation could be established between the results of the two tests, then we could assume that the shock test, which is so simple and easy to make, was a measurably accurate test of the dynamic qualities of the material. At present it does not seem

Jan 12, 1913

By David H. Browne, John F. Thompson

The literature dealing with the physical constants of nickel is so fragmentary and unrelated that a synopsis presents unusual difficulties. It is only within the last few years that investigators have understood the importance of placing on record not only the determinations they have made but also the composition, physical treatment, and past history of the material investigated. For this reason much of the earlier literature is valueless. Determinations have been made of the same physical constants on samples differing widely in origin, composition, and treatment, and the results differ widely among themselves. In the first place nickel is almost as flexible a term as steel. Its physical properties are widely influenced by its composition and treatment. It absorbs large quantities of gases and is exceedingly difficult to prepare in a state of chemical purity comparable to gold, silver, or copper. It is vitally affected by thermal and mechanical treatment. Hence in the following pages the recorded literature, where quoted, must be accepted with a certain reserve and used, as far as possible, as a check on later observations, in which these important factors are noted. In every case where new determinations are given, an attempt has been made to record all available information concerning the composition and treatment of the material used so that the data may serve as stepping-stones toward a wider knowledge of the properties of the metal. As this synopsis is an attempt by men of metallurgical training to do what should long before have been done by physicists, it is to be expected that certain errors may have crept in. Any corrections or suggestions

Jan 1, 1921

By M. N. Dunlap

Tries article summarizes the successful incorporation of a flash-flooding stream into the tailing-disposal system at the St. Joseph Lead Company's Federal Division mill, in St. Francois County, Missouri. The mill was built in 1906, by the Federal Lead Co., as its No. 3 mill for the concentration of southeastern Missouri lead ores, and damming Davis Creek was first considered in 1908. Plans were made also in 1925 and in 1937. Dam layouts varied from a reinforced concrete structure to a barrier built of tailings alone. All were abandoned because of liability that would be incurred by flashflood rupturing of an incompleted dam. By 1942 mill capacity had reached 12,000 tons daily and increasing tailing-disposal costs again focused attention on the Davis Creek basin. This time the problem of riskless dam building was solved. Moreover, most of the items that appeared in the answer were materials that normally required wasting and the major portion of labor involved performed functions that it would normally have done, without constructive benefit, elsewhere. The new layout also made possible advantageous changes in mill-water supply pumping; static head being reduced from 514 ft to 95 ft, friction head from 4900 ft to 2860 ft, and pumping can be done now at periods of low power demand. The following facts about the Davis Creek watershed explain the 36-year reluctance to reach these, and other, benefits. Size: 3600 acres. Outline: roughly pear-shaped, 2 1/2 by 3 miles at the largest dimensions. Topography: mostly hill land with steep valleys. Relief : 760 minimum to 1153 maximum. Maximum rainfall: 3.36 in. per hour. Permanent water: none natural. Now 2200 gpm discharged through 16-in. drill hole from mine pumps underground. Geology: the 17 acres near dam centerline is Bonne Terre dolomite covered with sand and gravel eroded from Pleistocene beds that cap some of the hills. The remainder of the pond basin is on Davis shale. Soil cover: mostly second-growth timber with some abandoned fields; all subject to careless burning, which reduces water-retaining ability. Flood history: flash-flooding that had taken at least one life. Downstream values: two railroad bridges before creek intersection with Flat River. Immediately below confluence, a highway bridge, a low-water crossing, a few business establishments and several blocks of residences. In July 1942 the following segments of an ingenious plan were put into operation. A ditch 270 ft long, 16 ft wide and 5 1/2 ft deep was excavated to bedrock in the gravelly soil along the proposed dam's centerline. This excavation, which exposed many gravel-filled channels, was run full of slimes drawn from a riser set in the top of an adjacent tailings-disposal

Jan 1, 1947

By H. C. Chang, N. J. Grant, A. R. Chaudhuri

During the creep of coarse-grained polycrystalline magnesium at elevated temperatures, a nonbasal type of slip was found to play an important role in the deformation processes. The nonbasal slip traces were examined metallographically in eight specimens (13 grains) and the observed glide plane located stereographically for each grain. The tests were run at 500&apos; and 700°F at stresses of 148 to 786 psi. Based on these measurements and theoretical calculations, the crystallographic elements for nonbasal slip were determined. WHEN a metal deforms by slip, the conventional appearance of the slip bands on the surface of a specimen is that of straight lines. Such is the behavior of the face-centered-cubic metals, as for example, aluminum. The particular slip system on which slip occurs in these metals is governed by the criterion of resolved shear stress. Work on the body-centered-cubic metals a-iron,&apos;. &apos; molybdenum, and columbium4 has shown that the process of slip is somewhat more complicated than the simple gliding of one close-packed plane of atoms over another in a close-packed direction and that it results in the formation of wavy and irregular slip traces on the surface. The recent reviews and experiments of Vogel and Brick and Chen and Mad-din3 show that, for the body-centered-cubic metals, the resolved shear stresses along the planes and the degree of close-packing do not necessarily determine the slip system. Theirs and other investigations indicate that a complete understanding of the slip process in the body-centered-cubic metals is not yet possible. However, one behavior displayed by all these metals is that the slip direction is invariably one of the close-packed directions <11l>. The wavy nature of the slip-band traces has been explained on the basis of cooperative slip by planes sharing this same slip direction.1&apos;3l&apos; It is generally acknowledged that, when the hexagonal-close-packed metal magnesium (axial ratio c/a = 1.624) deforms by slip at room temperature, it does so by basal slip in the close-packed direction <1I%>. This type of slip has the conventional appearance of straight lines and is governed by the critical shear-stress law. Schmid and coworkers" showed that basal slip was operative in the temperature range of —185" to 300°C (—300" to 572°F). Work by Servi, Norton, and Grant6 has shown that, during the creep of coarse-grained aluminum at high temperatures, new slip systems come into operation. The existence of a new high temperature slip system at temperatures greater than 225 °C (437°F) for magnesium was suggested also by Schmid. This was later indicated by Bakarian and Mathewson&apos; to be slip along the pyramidal planes (10i1) in the close-packed direction <11%>.* They * Mention will be made in the text of pyramidal planes and prismatic planes. The pyramidal planes referred to are the type I. order 1 of the form {10il); and the prismatic planes of the type 1 of the form (10i0). For the sake of brevity, they are termed in the teat as pyramidal (10il: and prismatic (10i0) planes, respectively. Where reference is made to the pyramidal plane type 1, order 2 of the form {10i2), they are referred to as the pyramidal planes of the type (10i2:. observed that this kind of slip resulted in irregular markings on the specimen surface. According to them, a possible cause for the appearance of the markings was due to "limited accessory slip on the pyramidal {10i2) planes." Burke and Hibbard," on deforming a single crystal of magnesium at room temperature, found evidence of slip on a pyramidal plane {1011). They explained it as being due to the effect of grip restraints. It is pertinent to note at this point that, although basal slip has received a fair amount of attention, only two specimens have been investigated, that of Bakarian and Mathewson and of Burke and Hibbard, to establish the elements of nonbasal slip in magnesium. During the study of the deformation mechanisms

Jan 1, 1956

C. W. MERRILL*—Mr. Hughes&apos; paper not only is very well presented but is most timely in that it covers a subject of vital interest to the United States. Tin is one of the strategic metals which has not been found here in appreciable quantities. The total United States tin output since the first recorded production over 100 years ago would not supply current consumption for a fortnight. On the consumption side, tin is extremely important in national defense because of its use in tin plate which, in the form of tin cans, makes it possible to feed properly the armies that the United States recruits from its civilian population in emergencies. Moreover, the internal combustion engines so important in powering tanks, planes, and other war machines, require large quantities of tin alloys for bearings and for soldering. These considerations, along with the fact that Malaya, historically, has been the leading source of tin to the United States, make the kind of information that Mr. Hughes has presented so ably. a matter of vital interest. Your Chairman, Mr. Romanowitz, in his introduction, referred to the fact that I had been a member of the United States delegations to the three meetings of the International Tin Study Group. Some comments on the Group&apos;s objectives and deliberations may be of interest. When it appeared that the International Tin Committee, the prewar producer&apos;s cartel, might soon revive its operations and extend its control agreement beyond the expiration date of Dec. 31, 1946, the United States Government became interested in some kind of an international trade organization concerned with tin which would give the consumers&apos; interest equal representation with the producers&apos; interests. An international meeting was called in London in October 1946 to consider this problem. I did not attend that meeting hut the result of the meeting was the organization of the International &apos;Tin Study Group which

Jan 1, 1950

By Aloys IL. Wollrab

The conditions that govern the selection of a suitable type of detachable bit for the small, isolated mine, for rock work and tunnel contracting and for the large mine are quite dissimilar, therefore intelligent recommendation of a particular make of detachable bit must involve consideration of many factors. Small, isolated mines may find advantageous a detachable bit that a larger mine cannot afford to use, because of more efficient conventional steel sharpening and steel-distribution practice, but a small mine may not be able to adopt the practice of large mines because of necessary capital expenditures for equipment for detachable-bit sharpening and . shanking. The perfect detachable bit, suitable for all conditions, has not yet been developed. Conventional Drill Bit in Use That drilling speed increases as the bit gauge decreases is well known, but since small-hole drilling is the exception rather than the rule the rate of such increase is probably not so generally recognized. Tests carried out by Holman Brothers Limited1 with 7/8-in. steel show that when bit sizes are reduced from I½ in., I3/8 in., and I3/16 in-; to I3/8 in., I1/4 in.., and I1/8 in., respectively, the volume of the hole is I 5 per cent less and the drilling speed 49 per cent higher. Recent tests by the United States Bureau of Mines2,3 in hard, uniform basalt showed that a reduction in average gauge from 2.077 to I,826 in., a difference of o.25I in., gave an increased drilling speed of 65 per cent. The limits to which a drill hole may be extended depend upon the loss in gauge. Since the conventional bit with 5° and 14° clearances did not possess sufficient reaming edge to permit the smaller gauge changes that were required for small-hole drilling, experiments were made in bit construction with a view to correcting this deficiency. This resulted in the adoption of the full reaming cross bit (having full Carr charac1erist.i~~) by some mines4 In order to drill holes having a minimum taper from the collar to the bottom of the hole, full reaming center-hole cross bits with 90° cutting angles, 5° and 14° wing tapers, forged on 7/8-in. quarter-octagon drill rods, are used in the conventional drill-steel practice at Hollinger. In the steel shop close attention is given to the condition of the dies and dollies, which, combined with a rigid inspection of the finished bit, ensures as nearly a perfect bit as call be forged economically. Shop practices and costs have been discussed in earlier paper.5,6 The method by which the radii for the special dies used for forging bits of different gauge diameter are obtained so that the points and reaming edges cut circles of the same diameter has been discussed by Hibbert. Requiremnts for Detachable. Bit for Hollinger Under these it it was appar- ent that it would be difficult to introduce a detachable bit that could successfully compete with the conventional bit already in

Jan 1, 1943

By T. E. Leontis, R. S. Busk

WORK was initiated several years ago at The Dow Chemical Company to determine the applicability of powder metallurgy processes to magnesium and its alloys. Although it was found possible to apply the normal techniques of compacting and sintering, it was discovered early that the technique of extrusion offered special promise. This technique and the alloys produced were therefore studied extensively, and the present paper is a partial report of those studies. It is expected that a second paper will discuss more extensively some of the alloy systems simply mentioned here. Although the literature on powder metallurgy is very extensive, there are only two articles dealing with magnesium13,14 and there is no reference to the direct extrusion of the powder of any metal without the preliminary step of compacting. Furthermore, no mention has been made of the possibility of designing alloys by the technique of powder extrusion, particularly alloys that cannot be made in any other way. Sauerwaldl3 discusses the extrusion of magnesium and aluminum powder to produce alloys containing nonequilibrium phases, but again he emphasizes the importance of pre-compacting before extrusion. There seems to be general agreement that some form of hot-pressing is essential to obtain in a compact the full theoretical density of the metal used.&apos;-" The nearest approach to the technique of direct powder extrusion is that of extrusion of pre-sintered compacts,&apos;-" for which the best review through 1944 is that by Kieffer and Hotop.11 Ensign* discussed a specialized technique of "extruding" already compacted and sintered gears for the purpose of sizing. Sauerwa1d13 discussed the compacting and extrusion of magnesium and magnesium-aluminum alloy band-saw chips. The properties of the extruded compacts were found to be comparable with those of extrusions prepared from solid billets. He also extruded a compacted mixture of magnesium and aluminum powder and found the properties to be somewhat different from those obtained on an extrusion made from a cast billet of the same composition. The second reference dealing specifically with the powder metallurgy of magnesium is Stern&apos;s patent," in which is described the extrusion of scrap chips and turnings following a hot-pressing and sintering step. Considerable emphasis in most of these articles is placed on the necessity of atmospheric protection to minimize the danger of oxidation. Experimental Procedure The first experiments were made with the small extrusion press shown in fig. 1. With this press, billets of about 1/2 in. diam are used to produce wire

Jan 1, 1951

By A. A. Brant

In this presentation, concepts of the formation and evolution of the universe, the earth, and the cyclic civilizations of man are broadly outlined. The 5 billion or more years of the universe and the 4% billion years of the earth are contrasted to the 5000 years of modern society and the 100 years of objective scientific breakthrough. THE UNIVERSE Let us start back as far as possible, to the beginnings of this universe, some 5 billion or more years ago. This is a time interval that can be crudely underestimated by the moon-earth tidal friction effects that have increased the length of the day by about 1/1000 second per century — from a 5 to 7 hour day to its present 24 — and have moved the moon away at 5 inches per year to its present 240,000 miles. The oldest stony meteorites from interplanetary space give an age dating of some 4.6 billion years, approximating the time of formation of our earth. Further, certain stars pulsate, the period of pulsation being related to their absolute brightness. Measuring apparent brightness and comparing, gives the distance away. Thus Hubble and Shapley of Harvard, from 1925 on, were able to show that the universe reached as far as our telescopes could scan. The Doppler shift of the hydrogen red lines could only mean that the nebulae, or galaxies, were moving away away at velocities increasing with their distances, by 180 km/sec velocity increase for every million light year&apos;s distance. In short, the universe is expanding like an exploded bomb. Comparing the velocity increase per million light year&apos;s distance again indicates a zero time of some 5 billion years&apos; Thus it appears that this universe had a finite beginning. Physical measurements and present theories permit some picture of our universe&apos;s birth. We know since Einstein that many forms of energy are equivalent, e.g., mass, and electromagnetic radiation, aspects of which are heat and light. Now with expansion, radiation density or equivalent mass decreases as a length factor to the 4th power, while mass as matter decreases at a length factor cubed. The temperature in outer space is now perhaps 100° absolute and the radiation mass equivalent is but 1/1000 the rarefied interstellar gas densities. Decompressing the universe to a starting point, however, raises temperature more rapidly than mass density, and results in a high radiation mass energy fraction, which since it is proportional to temperature to the 4th power suggests a zero point temperature of several billion degrees, brighter than any sun. "Let there be light and there was light," according to Genesis 1-3. Now what further initial conditions must there be to explain the relative abundance of the elements in the universe, which by spectral analyses of the earth&apos;s crust, stony meteorites, and the sun and stars is surprisingly uniform throughout. Some 55% of all cosmic matter is hydrogen, some 44% is helium and only 1% is made up of all the heavier elements in much the same proportions as on earth. These latter decrease logarithmically in abundance up to atomic weight 100, then level out. This consistent abundance distribution of elements in the universe may be generally explained by taking at Time Zero a hot neutron gas of density about 10-3 grams per cc, at a temperature of several billion degrees Centigrade, with a high radiation energy fraction. Generally neutrons break down into positrons and electrons within about ten minutes, but at the initial high temperature and radiation pressure would recom-bine. However, with rapid expansion and decrease of temperature and pressure, the neutron disintegration would run uncompensated and aggregation would result from neutrons and protons uniting in different degrees of complexity. The total calculated element aggregation time would be about one hour while the temperature still remained above one billion degrees. The element abundances formed would depend on density of the nuclear gas, simplicity of the atom formed, and the neutron capture cross section. Thus a higher density

Jan 1, 1964

By R. H. Frazier, C. H. Lorig, F. W. Boulger

This investigation establishes the effect of ferrite grain size resulting from various heat treatments on the transition temperature of a semikilled steel plate. Different austenitizing temperatures and various cooling rates were used. The ductile-brittle transition temperatures were determined by the Navy tear test and the keyhole Charpy test. THE data presented in this paper deal with quality characteristics of ship-plate material which were investigated in a research project sponsored at Battelle by the Bureau of Ships, Dept. of the Navy. Specifically, the object of this investigation was to establish the effect of ferritic grain size (resulting from various heat treatments) on the so-called transition temperature of ship-plate steel. Transition temperature is not a fixed property of steel. It is derived from a series of static or dynamic tests made at various temperatures and is qualified by specifying the type of test employed as well as the testing criteria. Because in earlier investigations of ship-plate quality1,2 the so-called Navy tear test and standard notched-bar tests (keyhole Charpy) proved to be useful in interpreting instances of brittle behavior of ship plate in service, these tests were used in the investigation reported in this paper. By definition,&apos; in the Navy tear tests the highest temperature at which one or more of four specimens breaks with a brittle fracture (that is, when less than 50 pct of the fracture area has a dull fibrous texture) is termed "transition" temperature. In the Charpy tests, the 12 ft-lb level of energy absorption was used as a criterion indicating the "transition" temperature, although other levels of energy absorption were also used for comparison. Earlier work" on ship-plate steels indicated that the temperature at which ship plate is finished has a very significant effect on its notched-bar properties. Plates rolled in the laboratory, where the finishing temperature can be carefully controlled, showed a 16°F decrease in tear test transition temperature when the finishing temperature was lowered 200°F (from X" to Y°F). The same plates showed a drop of 10°F in the keyhole Charpy transition temperature from the same decrease in finishing temperature. Commercially finished plates&apos; exhibit a similar trend. When the ferrite grain size of the hot-rolled laboratory plates was determined, a close relationship was found between the ferrite grain size and the notched-bar transition temperature." " he indicated relationship between grain size and transition temperature was in agreement with the findings on low carbon steels of Hodge, Manning, and Reichhold&apos; despite the differences in composition of the steels. The cooling rate after rolling varies from one steel plant to another. This variation changes the micro-structure" and appears very likely to affect the notched-bar properties of the steel plates. In the investigation summarized in the present paper, heat treatments simulating finishing practices in the hot rolling of ship plate were used in order to vary the ferritic grain size. It is believed that the indicated relationship between grain size and transition temperatures of the ship-plate material will prove useful in estimating the effect of rolling temperature and of cooling rates from rolling temperatures on the notched-bar properties of semikilled steel plate. Material The semikilled steel plate used in this investigation was a ¾ in. hot-rolled plate from an open hearth heat. Other plates from this heat have been used on many other studies performed for the Ship Structure Committee," "," and the heat has been identified as project steel "A". The chemical composition of the plate1 was 0.25 pct C, 0.49 pct Mn, 0.011 pct P, 0.045 pct S, 0.04 pct Si, and 0.004 pct N.

Jan 1, 1956

By G. L. F. Powell, L. M. Hogan

Large degrees of undercooling have been produced in bulk samples, 400 g, of copper and Cu-O alloys by melting in a slag of commercial soda-lime glass. The maximum degrees of undercooling obtained for copper, hypoeutectic and hypereutectic Cu-O alloy samples were 208°, 218°, and 97°C, respectively. No grain refinement as a function of undercooling was observed for the pure copper samples although in Cu-O alloys there was a marked decrease in grain size at degrees of undercooling greater than 150°C. The grain size change is the result of recrystallization during or immediately following the freezing process. THE first report of a large degree of undercooling in a bulk sample of metal was that by Bardenheuer and Bleckmann1 who produced 258°C undercooling in a 150-g sample of iron by melting in a glass slag. Garbeck2 extended this technique to nickel, cobalt, and copper and reported maximum undercoolings of 220°, 230°, and 60°C, respectively, while Fehling and schei13 undercooled a large number of metals as 2 to 20-g samples slagged in glass. Subsequently, one of the authors4 applied the glass slag technique to bulk samples, -500 g, of silver and obtained a maximum undercooling of 250°C. It was concluded that impurities which normally catalyze nucleation at small degrees of undercooling could be removed by oxidation and solution in a glass slag. Large undercooling of bulk samples of iron, nickel, cobalt, and their alloys has also been reported by other authors.8&apos;10&apos;11 Of the five metals mentioned above, copper was the only one which had not been undercooled by at least 200°C in the form of a large bulk sample. Since copper exhibits high liquid solubility for oxygen, as do iron, nickel, cobalt, and silver, it was considered that a much larger degree of undercooling than that observed by Garbeck for copper should be possible. This was obtained by modification of the technique applied previously to silver and the results of undercooling experiments with 400-g samples of copper form part of this paper. The undercooling behavior of Cu-O alloys was also studied, and the influence of a small oxygen content on the grain structure of undercooled copper was observed metallographically. 1) EXPERIMENTAL The copper was obtained as oxygen-free high-conductivity copper, the major impurities of which were Fe 0.01 pct, Zn 0.015 pct, and Si 0.02 pct. Melting was carried out in an open-ended vertical cylindrical fur- nace wound with Kanthal wire. A schematic diagram of the experimental setup is shown in Fig. 1. The undercooling technique previously used for silver4 involved preoxidation of the samples by melting the silver in contact with the atmosphere. The oxygen content was subsequently reduced by freezing the samples under a glass slag, whereby the oxygen was evolved as gas and the continuous glass cover over the surface prevented re-solution of oxygen when the sample was remelted. Since oxygen is not released as gas when a Cu-O alloy is frozen. the technique had to be modified for use with copper. Also, copper is oxidized during fire refining so that an in situ preoxidation treatment of the samples was not considered to be a prerequisite to large undercooling. Experimentation proved that this supposition was correct. Instead, it was found that care was necessary during melting of the copper under glass to minimize oxygen pickup. Samples of copper weighing 400 g were prepared by adding 50-g pieces of copper to a vitreous silica crucible partly filled with soda lime glass at a temperature of approximately 1000°C. Each piece was quickly immersed in the glass slag and held at this temperature until the oxide coating on the surface decomposed. This change was easily observed and coincided with the formation of gas bubbles in the glass

Jan 1, 1969

By C Macquarie, Maurice Cook

Normally the grain size of cold-rolled and annealed copper sheet is of the order of 0.02 to 0.06 mm., and 0.1 mm., for example, would, for many purposes, be regarded as undesirably large. The occurrence of very large grain sizes in a few isolated cases of copper sheet led the authors to inquire into the causes giving rise to such unusual results. During the course of this work a very large number of experiments have been carried out to determine the effect of varying the conditions of the final and penultimate rolling and annealing operations, as well as of earlier rolling and annealing treatments. A correspondingly large number of observations have been made, but within the space of one paper it is possible only to outline relatively briefly what appear to be the more important of these experiments and observations. The presentation of the results does not follow chronologically the order in which the experiments were carried out and they have been rearranged for the sake of simplicity. In recent years a considerable amount of work has been done in connection with the recrystallization and grain growth in metals arid alloy. that take place on annealing, and a number of generalizations have beell reached. It is known that the crystal size in wrought material in the annealed condition depends on a number of factors, including the time and temperature of the annealing operations and the nature and amount of cold-work to which the material has been subjected. Results. however that are not covered by these generalizations can be obtained, which, in some instances, may even appear to be contradictory to them. Xccortling to these generalizations gradual changes in grain size are effected by progressive variation of the factors involved in annealing or cold-working. The work recorded in the present paper, however, relates to the development of grain sizes which are far beyond those normally encountered in ordinary annealing operations and far in excess of grain sizes which,

Jan 1, 1939

By F. V. Lenel, G. S. Ansell, J. A. Dromsky

The growth of aluminum oxide particles in a nickel matrix was studied eve?. the temperature vange of 2140° to 2470°F. The instability of the dispersed alumina was shown to be independent of the crystal structure of the alumina. The activation energy for the growth of the dispersed alumina was found to be 84.7 1 2.0 kcal. The particle radius increased as a function of time. These results indicate that the growth is not diffusion controlled. It is believed that the rate controlling mechanism is the dissolution of the aluminum and oxygen atoms into the nickel lattice. THE strength properties of alloys which consist of a finely dispersed second phase in a metallic matrix depend upon the spacing between the second phase particles. It is therefore desirable to achieve very fine dispersions in these alloys. Furthermore, to retain the properties these very fine dispersions must be stable during fabrication and service of the alloys. The best known of the dispersion strengthened materials, the SAP type alloys, which consist of a dispersion of aluminurn oxide in aluminum, have exceptionally good stability up to the melting point of aluminum. There is evidence, however, that other dispersion strengthened alloys, even those consisting of refractory oxides in a metal matrix, may be less stable. This investigation is concerned with the stability of Ni-Al2O3 alloys in the temperature range in which these alloys are usually fabricated. The mechanical properties of Ni-Al2O3 alloys at elevated temperatures have been previously investigated by Crelnens and rant,&apos; and Gregory and Goetzel.2 The behavior of these alloys in stress rupture tests appears to indicate that at temperatures below 1800°F they are highly stable. There is some doubt, however, as to their stability at the higher temperatures used during the conventional fabrication. Cremens and Grant, in preparing their test alloys, cousolidated, by powder metallurgical techniques, nickel powders as fine as 0.13 µ diam and alumina powders as fine as 0.018 µ. Metallo- graphic examination of the alloys following fabrication revealed that none had interparticle spacings of less than 2 µ. Considering the size of the original component powder particles, it is likely that the dispersions coarsened during fabrication. Gregory and Goetzel, in their studies of extruded alloys of 80 pct Ni—-20 pct Cr matrixes with nonmetallic dispersion, observed a definite coarsening of the alumina dispersions in alloys sintered at 2280°F as cantrasted to those sintered at 2000oF. Similar observations on the spheroidization and growth of thoria particles finely dispersed in a nickel matrix were made by D. K. Worn and S. F. Marton.3 As a result of such coarsening, much of the effort expended in the preparation of very fine powder mixtures would be lost. The mechanical properties of the alloys which had experienced coarsening would be expected to be poorer than if the original dispersions had been retained. EXPERIMENTAL PROCEDURE Ni-Al2O3 alloys were produced from powder prepared by a coprecipitation technique. Aluminum hydroxide and nickel hydroxide were coprecipitated from chloride solutions of the metals. The mixed hydroxides were calcined to form metal oxides and the nickel oxide in the mixture was selectively reduced to nickel by treating it in hydrogen. Specimens were compacted from the resultant powder which consisted of a fine, uniform mixture of aluminum oxide and nickel particles. The compacts were sintered by resistance hot pressing4, a densification technique which requires exposure times of the order of only a second or less at elevated temperatures. A conventional sintering process was not used, since the temperature required for densification would have to be in the region in which the stability of the dispersion was to be studied. A series of hot pressed specimens were treated in hydrogen at temperatures from 2140o to 2470°F (1171o to 1355oC, for times up to 120 hr. Changes in the microstructures were studied by electron microscopy using the two-stage preshadowed carbon replica method.5 In performing a lineal analysis on a series of micrographs from each specimen it was found more convenient to determine the mean free path between alumina particles rather than particle radii as the parameter of growth. Although these quantities are directly proportional for only spherical particles, the alumina particles in these alloys

Jan 1, 1962

By James A. Barr

Phosphate rock is a natural rock containing one or more phosphate minerals usually calcium phosphate, of sufficient purity and quantity to permit its use, either directly or after beneficiation in the manufacture of commercial products.1 The principal minerals in phosphate rock have the apatite structure which may be represented by the type formula: Ca10(X2) (PO4)6 where X represents the hydroxyl group (OH), chlorine or fluorine, either singly or collectively. The calcium may be partly replaced by sodium, magnesium, and other positive ions such as manganese, strontium, lead, uranium, cerium, yttrium and other rare earths. The PO4 radical may be partly replaced by small quantities of UO4, AsO4, SiO4, CO3, SO4, or Vo4. A typical commercial rock is usually a calcium phosphate containing 3 to 4 pct fluorine, the major impurities being limonite or other iron oxides, clay, aluminum phosphates and silica as quartz sand. A little vanadium is present in most of the domestic rock deposits (except the Tennessee Brown Rock), according to Jacob, Hill, Marshall and Reynolds! A little uranium occurs in the Florida leached zone, as will be brought out later. The chemical analyses are reported as P205, or tricalcium phosphate Ca3(PO4)2, the latter often designated by the trade name BPL (bone phosphate of lime). Commercial analyses usually report iron and alumina as oxides, lime as CaO and silica or insoluble. Colony3 examined many samples of apatite, staffelite, dahlite and American phosphorites and concluded that all have identical X-ray diffraction patterns. The phosphates in the phosphate rock have very minute crystalline structures. The mineral apatite Ca3(F.Cl) (PO4) 3 is the principal primary source of the element phosphorus, and occurs widely distributed in igneous rocks but rarely in a minable mass. Only about 12 pct of the world production of phosphate rock comes from primary apatites; the remainder is derived from secondary phosphorites. These phosphorites have been formed by the alteration of sediments by solutions containing phosphoric acid. Such solutions have come from the weathering or leaching of igneous rock containing apatite, bone deposits of prehistoric animals, marine life or guano deposits. These phosphorites are mostly alterations of phosphatic limestones. The sedimentary phosphate deposits are of marine origin and may have been enriched by subsequent solution of the more soluble calcium carbonate by waters containing carbon dioxide, by physical concentration by wave action, and by redeposition of the dissolved phosphate ions. Uses of Phosphate Phosphorus is the spark of life and is the structure builder and one of the main elements of plant food (fertilizer). Without phosphorus, life cannot exist. A "complete" plant food[t] in addition to phosphorus compounds contains potash, which acts as a catalyst to convert nutrients to useful forms, nitrogen to supply the growth element and many minor elements. The cycle of supply of phosphorus is from the apatite to solution and soil, absorption of plant life, decay and return to the soil or by animal life feeding on the plants. With insufficient supply of phosphorus in vegetation, life is not prolific. If crops are removed from

Jan 1, 1960

By O. Jay Myers

THE war effort has furnished the necessary impetus for better magnesium foundry practice. Four or five years ago, there were but a few formulas in general use for cores and mixtures for magnesium castings. Certain sands, binders, and inhibitors were specified and the proportions of these materials in each mixture were maintained between very narrow limits. As more and more war industries entered the field, much research was carried out and methods and practices were improved. Magnesium founding is still in a state of flux; therefore it is not uncommon to find one foundry spraying inhibitors on its cores, and another foundry using sand mixtures with incorporated protective agents. The basic core or dry-sand mold mixture for magnesium in use today is compounded with sand, core oil or resin binder, cereal, and moisture. Core oil or resin binder are added for baked strength while the cereal binder and moisture are for green strength. The normal mixtures (based on the weight of the sand) contain from 0.5 to 1.5 per cent of both cereal binder and core oil, and the moisture content varies between 1.5 and 5 per cent. The ratio of core oil to cereal binder varies from 60:40 to 40:60, while the correct amount of moisture depends upon the method of coremaking. PROTECTIVE AGENTS In all magnesium practice, protective agents are used in conjunction with the core and molding sands to prevent oxidation of the metal. The use of these inhibitors is not novel, but publications covering this field are not entirely adequate. Beck1 says Magnesium alloys decompose water to form magnesium oxide, hydrogen being liberated in the process (Mg + H20 -+ H21 + MgO). This reaction results in the blackening of the skin and the appearance of areas of porosity on the casting surface, the cavities of which are filled with a grey oxide powder (these are termed `burns&apos;). Although sand cores for magnesium castings are thoroughly dried during the baking cycle, burning will take place on the castings unless the metal is protected properly. This type of burning is more difficult to define than the "water-magnesium" reaction cited by Beck. A possible explanation may lie in the following equation: 2Mg + 02 -s 2MgO Here, the source of the oxygen is not water, but the air in the mold cavity, together with the chemically combined oxygen in the core-binding media. Generally, two methods are used to prevent this reaction from taking place.

Jan 1, 1945

By R. E. Hobart

THE development of the Hauto power plant and the claims made by various engineers that electricity was more economical than steam for power purposes in and about the mines; led the Lehigh Coal and Navigation Co., in 1911, to conduct a test to ascertain the consumption of power used by a large steam hoisting engine. The question being one on which no reliable information could be found, and the opinion of various engineers differing to such an extent, it was decided that a test under actual operating conditions was necessary. This was arranged for at one of the collieries. The engine selected was a 30 by 60-in. (76.2 by 152.4-cm.) piston-valve engine of modern type, and comparatively new. The boiler plant from which the hoist received its power was about 600 ft. (182 m.) from the engine, the latter being fed by a 10-in. (25.4-cm.) steam line insulated with magnesia pipe covering. Two batteries of the boiler plant, aggregating 1200 hp., were cut off and fed into a separate steam line leading direct to the hoist engine. Steam auxiliaries, consisting of feed-water pump and blowers, were fed by the boilers in test, and their consumption charged against the hoist. A barrel weighing device was installed, as it was felt that this would be the most accurate way of determining the consumption of water. The fuel, No. 3 buckwheat, was carefully weighed, and every precaution was taken to make the test accurate in every particular. The test was run for 1 week, or a total of 168 hr. A record was kept of the number of trips hoisted or lowered, and continuous indicator cards were taken. One particular set of cards was taken with the hoist operating balanced, and also with the hoist operating with no counterweight other than the empty cage, the coal in the car being weighed. The speed of the hoist was taken by means, of a graphic recording instrument which registered the number of revolutions every 5 sec. From this record, speed-time curves were plotted.

Jan 2, 1918

By L. H. Dushak

DURING the war period of quicksilver activity there were a number of departures from what may be termed the classical quicksilver metallurgy. Attempts were made to beneficiate low-grade ores by gravity concentration and flotation; mechanical furnaces began to replace the Scott furnace and the vertical coarse-ore furnaces, and condensers of sewer tile and redwood tanks were used in place of the older brick and stone condensing chambers. Other developments that have occurred during the current period of quicksilver, activity are mainly in the nature of improvement and further refinement of those started during the war period. Each period of quicksilver activity has been accompanied by the proposal of various new processes, including wet methods for the treatment of quicksilver ores and innovations in furnaces, retorts and condenser equipment. As far as the author knows, nothing of economic significance in the way of "new processes" has been developed. There is in fact no real need for any essentially new process for the treatment of quicksilver ores; the direct furnace treatment is simple and inexpensive. Moreover, with fare exceptions, the quicksilver industry has no complex or refractory ore problems corresponding to those which are receiving more and more attention from metallurgists in other branches of the nonferrous field. Under these conditions improvements in quicksilver metallurgy must be looked for through the adaptation of current developments in engineering and metallurgy generally to the particular needs of quicksilver practice rather than through the invention of new processes.

Jan 1, 1930