Search Documents

By George A. Moore, Donald P. Smith

In spite of many investigations of the occlusion of hydrogen in iron, the nature of the process and the reasons for the accompanying effects upon the metal are still open questions. This is in large part due to three causes: (1) the difficulty of obtaining iron of adequate purity as starting material; (2) the occurrence of allotropic transformations, which complicate the effects; and (3) the fact that the body-centered cubic modification does not lend itself readily to crystallographic investigation. The present paper attempts a critical review and correlation of the somewhat scattered and disconnected existing observations, and an experimental determination of the extent to which the conclusions that appear to follow from these are applicable to iron of really high purity, studied under well-defined conditions. Review Although only a comparatively few investigations have so far been made on the pure system iron-hydrogen, there is a much larger volume of literature which throws some light on the problem but falls short of a place in the systematic investigations, either because no attempt was made to measure equilibrium conditions or because the metal used was not iron or the gas not pure hydrogen. Such results have been variously dismissed in the past as of no importance, or as too complicated to try to explain; or they have been explained in terms of any of a dozen or more pictures, each of which is contradicted by data from other sources. The present importance of these data thus arises from their very mass and diversity, which present a picture of occlusion as a phenomenon whose variability cannot be ignored. We have attempted to organize the literature into groups comprising similar experiments or data leading to similar conclusions, thus of necessity sacrificing accuracy of historical order. Lattice Occlusion.—Throughout this discussion, the term "lattice occlusion" will be used to denote the formation of a simple solid solution of a gas in a metal lattice, usually of interstitial distribution. The word

Jan 1, 1939

By J. Hunter

DuXing 1942, Louisiana attained the rank of fourth among the great oil-producing states of this country. Its present prominent position is the result of an orderly and systematic program of exploitation with emphasis on conservation. Even before the functioning of M-68, the Federal spacing order, development and production in Louisiana were regulated by various acts of legislation, the most recent of which and by far the most effective is Act 157 of 1940. Under the authority of this act, it has been possible for the Department of Conservation to hold many public hearings and thereby to secure data and evidence regarding the feasibility of issuing rules and regulations for development of various oil and gas fields in the state. As a result of information compiled at such public hearings, many orders have been issued by the Commissioner of Conservation that have in most cases provided reasonable solutions to the problems that arise in the exploitation and development of fields in this state. Probably one of the most effective powers granted the Commissioner of Conservation in the state of Louisiana has been the authority to provide for fieldwide unitiza-tion and pooling of condensate fields. This has led to the erection of huge cycling plants in Louisiana, which permit the most efficient recovery of the liquid content of the reservoirs, and further conserve most of the gas reserve that undoubtedly will be of considerable future value. Many months have passed since various orders of the Department of Conservation were put into effect, and all are accomplishing their purpose; namely, the elimination of waste. Although the effectiveness of these orders provides considerable satisfaction to the members of the Department of Conservation, it is also a tribute to the members of the oil and gas industry in Louisiana, who, in addition to providing carefully prepared technical data, have also given unstinting cooperation and have thereby enabled the Department to cope intelligently with the many problems. Production On Dec. 31, 1942, oil and/or gas was being produced in 50 parishes, or 78 per cent of all the parishes in the state. Thirty-three of the parishes produced oil and gas, 12 produced oil, and 5 produced solely gas. This is indeed an enviable record for any state. However, it is reasonable to assume that eventually all parishes in the state of Louisiana will be productive. From a geological viewpoint, there is no apparent reason to assume otherwise—a point that a11 operators seeking oil and gas production in this state may well bear in mind. Twenty new fields were found during 1942—a rate of discovery that does not compare favorably with the 30 new fields found during 1941. The record of discoveries in Louisiana during 1942 is further disappointing when it is realized that 8 of the 20 new fields discovered were gas fields. During this period of war emergency, there are, of course, many

Jan 1, 1943

By Thomas Egleston

The copper-bearing rocks of Lake Superior are composed of a series of metamorphic rocks, comprised under the names of amygdaloid and conglomerate, in which the copper and silver found with them are pseudomorphs. These rocks, generally, have Well-defined walls which cause them to separate easily. Generally, the country rock is sterile, but it occasionally rises into the copper-bearing rock, and then carries copper. Usually, the amygdaloids carry copper, and the greenstones or melaphyres which encase them do not. There is a very generally received opinion that the copper in these beds occurs in shoots. This does not appear to be proved, though the opinion seems to have some foundation from the experience of the Calumet & Heela Mine, where a body of poor rock has been left, which, on the mine map, shows a general direction. The theory may be true of that individual mine, but too little work has been done in the other mines to draw any decided conclusion. The copper is very unequally disseminated in the rock, if any given piece be taken as an example, but, if the whole copper-bearing series be considered, its distribution is uniform. It may prove that there are certain directions in which the copper has been deposited more abundantly than in others, and these may be found to correspond with certain geological causes, but up to the present time the knowledge gained is not sufficient to warrant any general conclusion. These rocks are supplemented by a series of true fissure veins, of which there are several systems, making the amount of native copper very large. Unfortunately, except in the fissure veins, known as " mass-mines," the copper is so scattered through the rock, and is in such a fine state of division, that, although it is not always difficult to mine, it is always difficult to dress it sufficiently to make it pay. The metal is so unifornily distributed throngh these copper-bearing rocks that detached pieces, called " float," are found in digging on almost any land in the country. These pieces vary from very small fragments, weighing not more than a few ounces, up to many pounds. In one instance, in making an excavation for a cellar of a

Jan 1, 1879

By Gary E. Melickian

Last year's review was characterized as a year of politics and began an era of legislation. The 1972 review can be similarly characterized, with even more rigid health and safety regulations and environmental legislation. The mining industry should be aware of what's happening in the nuclear power and other fields as a result of the National Environmental Policy Act (NEPA) of 1969, where the environmental impact of most major construction activities are already under close scrutiny. Section 102 of NEPA requires that all federal agencies include a detailed statement on specified environmental conditions as part of every report on proposed actions significantly affecting the quality of the human environment. All such environmental reports must consider the same general conditions: • The environmental impact of the proposed action. • Any adverse environmental effects which cannot be avoided should the proposal be implemented. • Alternatives to the proposed action. • The relationship between local short-term uses of man's environment and the maintenance and enhancement of long-term productivity. • Any irreversible and irretrievable commitments of resources which would be involved in the proposed action should it be implemented.

Jan 2, 1973

By Walter P. Jenkey

[ ] I. THE REDUCING ACTION OF CARBON AND OF HYDROCARBONS. Carbon has long been recognized as one of the most powerful reducing agents in the deposition of ores. Investigations, made by myself, of the zinc- and lead-deposits in Southwest Missouri, in the region centering about Joplin, where the formation of the metallic sulphides has been due to the action of bitumen, carbonaceous shales and bituminous coal, Lace afforded abundant evidence that the solid oxygenated hydrocarbons, particularly, when in fine powder and in suspension in the waters circulating through the ore-bodies, are the most energetic and powerful reducing agents known. Bitumen, liberated by the decomposition of the ore-bearing limestone, is found in the Joplin mines in all degrees of fluidity and hardness, dependent on the amount of oxidation it has undergone. From semi-fluid maltha it grades into partly oxidized mineral-pitch, which, by further oxidation, changes to hard asphalt, finally breaking up, from continued absorption of oxygen, into a fine powder resembling in appearance powdered coal. In this condition oxidized bitumen, from its light gravity, is transported readily in suspension in the underground circulating-waters. Bituminous coal and black carbonaceous clays and shales occur as surface formations, often in intimate association with

Jan 1, 1913

By N. H. Jensen, B. L. Sackett, Carlos Bardwell, Simon Jacobson

Lead smelting has been an important industry in Utah for many years. The first lead smelting was done, over 60 years ago, at the Rollins mine in Beaver County, by burning heaps consisting of alternate layers of wood and high-grade carbonate ore. The lead thus obtained was molded into bullets. With the development of the mines, the problem of cheaper handling of the ore became important. The only outlet for this ore was Swansea or the Atlantic Coast but to ship to either cost $150 per ton or more for treatment and handling. From 1864 to 1871, experimenting was done with blast, Scotch hearth, and reverberatory furnaces, with the blast furnace surviving as the standard plant. The first crude furnaces were circular or hexagonal in shape, and were made of adobe and stone, which quickly burned out. They were small, about 21/2 ft. in diameter, and smelted from 3 to 10 tons in 24 hr. The metal had to be tapped from the bottom of the crucible, necessitating a shut down of the furnace during this process. This procedure caused salamanders to form around the tap hole when the furnace was started again, which frequently resulted in freezing. The campaign lasted until a tap of bullion was made. The first successful plant of the crude stone type was operated in 1870. From 1870 to 1872, there was a smelter building craze in the state. During that period, about 20 furnaces were built, chiefly near the mines, and their operation was limited and sporadic. The work was then placed in the hands of trained metallurgists, who standardized on the rectangular form of furnace. In 1871, Daggett, at the Winnamuck mine in Bingham, installed water-jackets around the smelting zone of the furnaces. These furnaces were circular; the diameter at the tuyere line was 3 ft. 6 in. and at the charge floor 5 ft. 3 in. The height from tuyere line to charge floor was 14 ft., height of tuyere line above top of crucible was 3 ft. 8 in. Furnace capacity was about 14 tons per day, with a campaign of about 16 days. Cost of smelting was about $44 per ton. The ores making the

Jan 1, 1926

By William Fink

THIS paper is the nineteenth of a series from the Aluminum Research Laboratories, presenting the results of the investigations of equilibrium relations in aluminum-base alloys made from electrolytically refined aluminum. In previous papers equilibrium) relations have been deter-mined and correlated for 12 binary systems. Equilibrium relations have also been determined for portions of the aluminum corners of three ternary systems (aluminum-iron-silicon, aluminum-magnesium-silicon and alu-minum-copper-magnesium). The object of the present paper and those to follow is to increase our knowledge of the aluminum corner of the more important ternary systems. In 1926 Dix and Keith? suggested a new method for designating the phases encountered in alloy systems. The system has been used to a very limited extent 1,2,3. The system has since been slightly modified and will be used in this and future papers. In the system as modified, a phase is designated by placing in parentheses the chemical symbols of the elements essential to the formation of that phase. The symbols in the parentheses are separated by dashes in order to clearly distinguish them from a chemical formula. Elements that are not necessary to the formation of the phase in question, but which may be present in solid solution, are not indicated in the designation. If two or more phases would have the same designation according to these rules, they are dis-tinguished by prefixing Greek letters, and are definitely identified by X-ray diffraction patterns.

Jan 1, 1936

By Norman Brown, J. V. Rinnovatore

Substructures in explosively deformed and annealed ß brass have been examined by electron microscopy. In the explosively deformed condition, the structure contains a large density of straight screw type dislocations. Subsequent annealing up to 300oC produces low angle boundaries, which are characterized by superlattice dislocations, and expanded and contracted nodes. Evidence is given where two a(111) superlattice dislocations combine to form two a(001) superlattice dislocations. It is also shown that annealing at 400°C the networks disappear and that quenching from 400" C produces square and circular prismatic dislocation loops that lie on (100) and (111) planes, respectively. THE purpose of this work was to determine the effects of explosive deformation and subsequent annealing in a superlattice using electron microscopy. One of the first observations of explosively deformed structures was made by Hornbogen1 on a iron. Hornbogen found that screw dislocations were most prominent in the explosively deformed structure. He explained this result by suggesting that the edge components of dislocation loops move with the velocity of the shock front leaving a trail of extended screw components. Kressel and Brown2 observed explosively deformed Fe3A1, which is basically a body-centered type of superlattice in terms of dislocation geometry, and found that, as in the case of iron, screw dislocations were most prominent. It was also observed2 that, in cold-rolled and explosively deformed nickel, screw dislocations did not predominate, but rather a uniform network of dislocations was present in which the orientation of the dislocations was random. (Cell structures also have been observed by Nolder and Thomas3 for copper and by Johari and Thomas* for nickel). Kressel and Brown2 discussed the difference between dislocation morphology for bee and fee metals in terms of dislocation mobilities. They suggested that edge dislocations have a greater mobility than screw dislocations in bee metals but not in fee metals. Thus, the idea offered originally by Hornbogen1 is not valid since it should apply equally to fee and bee systems but does not. The results of recent work by Mikkola and cohens on explosively deformed Cu2Au are consistent with other observations for fee metals. They found that dislocations were randomly arranged but there was no significant cell formation. At high shock pressures, deformation twins are produced in fee metals.' High pressures in bee metal should induce the bee — fee transformation while the metal is under pressure. EXPERIMENTAL PROCEDURE The Cu-Zn alloy used in this work contained 51.4 wt pct Cu. Specimens of 0.5 in. diam and 0.012 in.

Jan 1, 1968

By B. K. Miller, R. S. Bradley

THE principal producing areas of fire clay in Missouri are: (I) the east central district, which includes Audrain, Callaway, Montgomery, Warren, and Boone Counties [ ] (Fig. I); (2) the St. Louis district, which includes St. Louis and St. Louis County; (3) the north central Ozark district, which includes Franklin, Gasconade, Osage, Maries, Phelps, and Crawford Counties. [ ] Most of the semiplastict fire clay is found in Audrain, Callaway, Montgomery and St. Louis Counties, and in St. Louis. Flint fire clay is found in Callaway, Audrain, and Montgomery Counties and in most of the north central Ozark district. High-alumina [ ] diaspore clay is found only in the north central Ozark district, except a few deposits found in Montgomery County. This paper is concerned with the semiplastic fire clay that occurs in the east central Missouri district near Mexico, Audrain County, Missouri, which is mined by the open-pit method as practiced by the A. P. Green Fire Brick Co. About one-fourth of the semiplastic fire clay in that district is mined in shaft mines, and three-fourths in open pits.

Jan 1, 1941

By John Alden

A CONSIDERABLE PROPORTION of the tonnage of aluminum used today has at some stage during its manufacture, been rolled. I. For one, therefore, was particularly pleased to hear that this Society was to hold a symposium on rolling of nonferrous metals. Metallurgists can well afford to direct their close attention to the metallurgy involved in this important operation. To one who has seen today's high production rolling mills for aluminum it is difficult to realize that the first aluminum rolling mill For sheet was installed a scant 55 yr ago, in 1892. This mill was a three-stand train of 2-high mills, driven by a steam engine and was operated for many years successfully rolling aluminum sheet. Mills for the rolling of aluminum rod were installed in 1899 to meet the demand For manufacture of electrical conductor wires and cables. Bars and rods in straight lengths were also made. While these mills were the first built for rolling aluminum products of these types some rod had previously been rolled on brass and copper mills. Not until many years later, in 1929, however, Were facilities provided for the rolling of structural shapes, such as I-beams and channels. Growth of the aluminum sheet business and the necessity for economical manufacture soon brought the realization of the economies resulting From-the rolling of sheet in long lengths and coiling it. A five-stand continuous mill driven by a steam engine, was in operation late in 1907. This took aluminum slabs coating from

Jan 1, 1948

By Walter Rosenhain

In selecting solid solutions for the subject of this lecture I have been guided by several considerations. The bodies known under that somewhat paradoxical name play a most important part in all types of alloys; consequently, a deeper knowledge of their constitution must 'be of fundamental importance to both metallurgical science and practice. Further, having been asked to deal with some of the more theoretical aspects of metallurgy, I have been tempted to describe certain considerations, which I believe to be novel, in regard to the nature of solid solutions. These considerations constitute a theory that requires much experimental confirmation, but they have passed the stage of speculations, for experimental evidence has become available and one inference after another, that can be derived from the theory, is found to be in accord with well-known facts. In putting before you these ideas and inferences, it must be understood that detailed quantitative proof of every step cannot be furnished. Our conclusions must therefore be stated with the reservation that their acceptance must depend on the manner in which the discovery of fresh facts may either confirm or confound them. If we wish to understand the structure of solid solutions we nust carefully realize the manner in which these bodies are formed in alloys. The formation of solid solutions is by no means confined to alloys, but it is desirable to confin5 attention, at the outset, to intermetallic solid solutions. It is not easy to formulate a precise definition of the term "solid solution." It may be said that a solid solution is a crystalline body formed from a liquid solution or from an intimate mixture of solids, or of liquid and solid, that retains in the solid state an admixture of the two substances (solvent and solute) as intimate as that which exists in a liquid solution. The term is undoubtedly paradoxical, for one usually associates solution with a liquid, but the difficulty cannot be evaded by using such a term as solidified solution, for this might refer to a solution that has set, or congealed, without undergoing crystallization. The German term mischkry stall avoids the difficulty and appears to

Jan 1, 1923

By Philip Davidson, Wm. B. Price

The object of this paper is to present, a survey of some of the physical properties of sheet nickel silver when subjected to cold rolling and when annealed at temperatures extending from 350" C. throughout the coininercial annealing range.. A number of alloys were taken from stock and analyzed. Four of these, representing low nickel and high nickel both with and without lead, were chosen for the tests. The analyses were as follows: Alloy Copper, Lead. Iron. Nickel, ManGanese, Zinc, PeR Cent. Per Cent. Per Cent. Per Cent. Per Cent. PEr Cent. A................ 64.68 Trace 0.194 6.73 0.06 remainder B................ 65.82 1.27 0.227 6.17 0.06 remainder C................ 65.44 Trace 0.345 17.83 0.08 remainder D................ 65.60 1.08 0.238 17.77 0.06 remainder These alloys were lolled in accordance with regular mill practice to approximately No. 6 R. & 6. gage. The bars (which were then coiled) were annealed together in a mill muffle and afterwards pickled in a 10 per cent. sulfuric-acid solution and cold rolled in stages of approximately one number (B. & S.) at a time to No. 18 B. & S. gage. After each stage, suitable samples were set aside for physical tests. Additional samples were chosen for tests after the bars were rolled to Nos. 8, 10, 12, and 14 gage. These samples were annealed together in the mill muffle and, after pickling, were finished on 0.050-in. gage, yielding a series of specimens 2, 4, 6, and 8 numbers hard for the subsequent annealing tests. Tensile test pieces 9 by 1 in. (22.9 by 2.5 cm.) were cut from both lots and the central portion was milled to give a test section 2 1/2 in. long by 1/2 in. wide. A distance of 2 in. was marked off on the edge of each specimen with light punch marks. In the case of the annealed alloys, Erichsen test pieces 4 by 235 in. were also taken.

Jan 1, 1921

By Robert Gorham Morse

This paper presents the results of an investigation made in the metallurgical laboratory of Columbia University, New York City. The object of the investigation was to determine how the tensile strength, the elastic limit, and the size of the grain, of a pure medium-carbon steel are affected by heating to successive temperatures between 500° and 1300° C., with slow cooling therefrom. Since Dr. Sorby's first investigations into the microstructure of steel, the study of the subject has been continued by Professor Martens, Mr. F. Osmond, Professor Arnold, Professor Howe, Mr. A. Sauveur, Mr. J. E. Stead, and many others. Among many valuable and interesting papers I mention the following as having a special bearing upon this investigation.* " Microstructure of Steel," by Albert Sauveur, Trans., xxii., 546 (1893); Microscopic Metallography," by F. Osmond, Trans., xxii., 243 (1893); "The Microstructure of Steel and the Current Theories of Hardening," by Albert Sauveur, Trans., xxvi., 863 (1896); "The Crystalline Structure of Iron and Steel," by John Edward Stead, J. Iron and Steel Inst., 1898. II.—Statement of Experiments. Through the kindness of Mr. N. Lilienberg, New York City, round rods 3/4 of an inch in diameter were obtained, which had been rolled from one ingot. The analysis of the steel was as follows : C, 0.343; Si, 0.027; Mn, 0.221; I?, 0.0266; S, 0.0037 per cent.

Jan 1, 1900

By M. S. Burton, B. W. Christ, G. V. Smith

Evidence of the effects which high-angle grain boundaries and veining subgrain boundaries have on the yield phenomenon of zone-refined iron is reported. Room-temperature tensile tests on 50-mil wive at several gram sizes produced upon recrystallization at diffevent temperatures below 910C (a-y phase-transfornzatzon temperature) show that upper and lower yield stress decrease with increasing grain size. The upper yield point effectively disappears at grain sizes of 81 and 102 u in samples of this diameter. However, samples of 129 p grain size. produced during recrys-tallization at 950°C, exhibit a pronounced upper yield point and an increased lower yield stress. Possible causes of the reversal in the grain-size dependence of yielding are discussed. Veining substructure, detected with picval-HC1 etchant, but not with 2 pct nital, is formed during the a-y transformation, and is believed to account for the observed effecls. The strengthening associated with high-angle boundaries in zone-refined tron is discussed in terms of: 1) the stress dependence of slzp multiplicity, and 2) the stress dependence of dislocation emission from grain boundaries. WIDE use of transmission electron microscopy and dislocation etch-pitting techniques has led to a growing awareness of the presence of dislocation substructures in annealed pure metals. Whereas much speculation'-4 has developed about the influence which subgrain structures have on the mechanical behavior of metals, particularly the yield strength, only limited experimental evidence correlating subgrain structures with lower yield strength has been presented. 2,3,5-7 It is the purpose of this note to present experimental evidence of the effects which grain boundaries and subgrain boundaries have on both the upper and lower yield strength of zone-refined iron. Effects due to high-angle boundaries formed upon recrystallization below the a-y phase transformation are compared with effects due to veining subgrain boundaries formed upon "recrystallization" above the a-y phase-transformation temperature. These effects are further compared with the reported influence 2,3,5-7 which low-angle boundaries have on the lower yield strength of bcc transition metals. EXPERIMENTAL PROCEDURE The starting material for these experiments was a 1-in.-diam zone-refined ingot prepared at Battelle Memorial Institute. Initial purification of electrolytic iron by vacuum-induction melting was improved by a floating zone-melting treatment in ultrapure hydrogen.' Chemical analysis of this zone-refined iron appears in Table I. Tensile samples of 50-mil wire were prepared by rolling and drawing portions of the ingot. An intermediate recrystallization anneal at 625°C after rolling to a reduction in area of 85 pct was carried out in an evacuated Vycor capsule (10-=5 mm Hg). Further reduction in area of 91 pct was followed by recrystallization in evacuated Vycor capsules at temperatures between 600" and 950°C, see Table 111. All samples

Jan 1, 1967

By J. H. Wernick, J. E. Kunzler

HIGHLY pure metals are needed for low-temperature electron transport studies in progress. Recent improvements in purification techniques, such as zone refining, have made it possible to obtain metals with improved purity. For some metals, the improvement has been to the extent that ordinary analytical techniques are inadequate and special methods are needed.1 For other metals purification is more difficult, so that simple but rapid analytical methods are desirable as an aid in evaluating the effectiveness of purification procedures. Furthermore, it is desirable to be able to determine the impurity level of the sample or ingot with the minimum of physical disturbance of the material. In order to aid in the preparation of purer metals, techniques involving the measurement of electrical resistance at liquid-helium temperatures have been devised for studying impurity distributions in zone-refined ingots and other bulk samples without destroying the ingot or its geometry. The method yields information on the variations in purity along the length of the ingot or sample and provides a measure of the overall purity of the material. Compared with ordinary analytical methods, the resistivity method is rapid, sensitive, and does not require significant physical disturbance of samples with reasonable shapes. It has the disadvantage that resistance measurements are not specific, i.e., they do not identify the impurity. However, this disadvantage is offset by the advantage of being able to establish a measure of the overall purity so far as electrically active" impurities are concerned. METHOD AND ITS BASIS The method is based on the well-known fact that the resistivity, at Liquid helium temperatures, of a reasonably pure metal containing no regions with additional phases decreases with increasing chemical purity or a decrease in the number of physical defects. It is convenient to separate the total resistivity into three parts: where is the resistivity due to the scattering of the conduction electrons by the lattice vibrations or phonons, p is the contribution due to physical defects, and originates from the effect of chemical impurities in the metal. Insofar as Matthiessen's rule is obeyed,2 pphys and pchem are independent of temperature. Except possiblyin the very purest metals, ptherm is negligible at liquid helium temperatures and For zone-refined metals, which normally are well annealed and consist of large grains, at the chemical purity levels thus far attained the available data indicate that pphys is negligibly small or at least constant throughout the ingot. Assuming that the effect of physical defects is negligible for isotropic metals, This assumption appears consistent with most of

Jan 1, 1959

By J. Hunter

DuXing 1942, Louisiana attained the rank of fourth among the great oil-producing states of this country. Its present prominent position is the result of an orderly and systematic program of exploitation with emphasis on conservation. Even before the functioning of M-68, the Federal spacing order, development and production in Louisiana were regulated by various acts of legislation, the most recent of which and by far the most effective is Act 157 of 1940. Under the authority of this act, it has been possible for the Department of Conservation to hold many public hearings and thereby to secure data and evidence regarding the feasibility of issuing rules and regulations for development of various oil and gas fields in the state. As a result of information compiled at such public hearings, many orders have been issued by the Commissioner of Conservation that have in most cases provided reasonable solutions to the problems that arise in the exploitation and development of fields in this state. Probably one of the most effective powers granted the Commissioner of Conservation in the state of Louisiana has been the authority to provide for fieldwide unitiza-tion and pooling of condensate fields. This has led to the erection of huge cycling plants in Louisiana, which permit the most efficient recovery of the liquid content of the reservoirs, and further conserve most of the gas reserve that undoubtedly will be of considerable future value. Many months have passed since various orders of the Department of Conservation were put into effect, and all are accomplishing their purpose; namely, the elimination of waste. Although the effectiveness of these orders provides considerable satisfaction to the members of the Department of Conservation, it is also a tribute to the members of the oil and gas industry in Louisiana, who, in addition to providing carefully prepared technical data, have also given unstinting cooperation and have thereby enabled the Department to cope intelligently with the many problems. Production On Dec. 31, 1942, oil and/or gas was being produced in 50 parishes, or 78 per cent of all the parishes in the state. Thirty-three of the parishes produced oil and gas, 12 produced oil, and 5 produced solely gas. This is indeed an enviable record for any state. However, it is reasonable to assume that eventually all parishes in the state of Louisiana will be productive. From a geological viewpoint, there is no apparent reason to assume otherwise—a point that a11 operators seeking oil and gas production in this state may well bear in mind. Twenty new fields were found during 1942—a rate of discovery that does not compare favorably with the 30 new fields found during 1941. The record of discoveries in Louisiana during 1942 is further disappointing when it is realized that 8 of the 20 new fields discovered were gas fields. During this period of war emergency, there are, of course, many

Jan 1, 1943

By J. W. Spretnak, G. W. Cunningham

A study has been made of the growth and disappearance of voids in the interface of pressure bonded copper. The formation of visible voids is primarily due to spheroidization and coalesence of microvoids produced during the application of pressure. The microvoids could be prevented from forming by the application of high pressures or by increasing the ductility of the copper. Migrating grain boundaries were found to be more effective in void removal, than stationary grain boundaries. DURING the course of an investigation on the mechanism of pressure bonding, it was found that voids formed in the bonding interface which inhibited migration of the interfacial boundary and grain boundaries in the bond region. Therefore, an effort was made to determine the nature of the voids and how they form, grow, and disappear. This paper reports the results of such an investigation. The existence of interfacial voids is not solely a characteristic of massive components of metal which have been bonded by the application of heat and pressure, but is a phenomenon which has been observed in sintering as well. Simonsen attempted to study the sintering process by hot-stage microscopy and thereupon observed the formation of interparticle porosity as sintering proceeded. It was assumed that the porosity was due to grooves created at the location where grain boundaries joined the surface of the particle. Pranatis, Castelman, and seigle2 have also observed voids along the areas of contact in wound-wire specimens used for sintering studies. They did not discuss the point in detail since this behavior was not general, but they did suggest that the voids might develop as a result of stresses along the interparticle contact area. In previous investigations on pressure bonding, workers3 have suggested that voids may exist in the region where mating surfaces are placed in intimate contact, but the existence of the voids was not verified and no attempt was made to study the growth and disappearance of these voids. Durst noted the existence of pores in roll-clad structures prepared by cold reducing two sheets to force them in contact and then annealing to improve the bond. Since his unbonded regions contained a gas which he assumed to be insoluble, he proposed a mechanism which consisted of spheroidization of the unbonded regions and a growth of the contact area, but no speculations were made regarding disappearance of the gas filled pores. One interesting comment made by Durst was the suggestion that flattened voids with sharp corners which are produced during roll bonding will have a greater driving force for spheroidization than the more rounded pores created by pressing metal powders and thus spheroidization and neck growth will occur at lower temperatures. In this study it was necessary to demonstrate conclusively that voids can actually exist in the interfacial bond area. Experimental work was then directed toward a study of the mechanism whereby the voids grow and subsequently disappear.

Jan 1, 1963

By James Aston

THREE years ago the writer presented a paper on the trend of development in the wrought iron industry,1 wherein was described a process in the development of which he has been a factor, which at that time had passed through several years of progressive experimental development but which had not then been put upon a commercial scale of operation. The present paper deals with two years of observation and experience in the commercial operation of a plant by the A. A Byers Co. at Warren, Ohio. It will not enter into the controversial field of the relative merit of wrought iron and steel in various classes of service, nor will it elaborate upon the characteristic services or fields of utility to which wrought iron is particularly adapted. It is sufficient to state that the wrought iron industry is upon a substantial basis and that the material finds service in pipe, where its advantages are in superior corrosion, fatigue, welding and threading qualities; in bar iron for staybolts, engine bolts, and rivets, demanding maximum service against corrosion and fatigue; in plates for corrosion service; and in chains, because of welding and shock-resisting characteristics. In short, ability to withstand the stresses of shock and vibration, or the ravages of corrosion, to hold protective coatings, and to give maximum efficiency in welding, are its features of relative superiority. If these features were not well recognized, the wrought iron industry would have shrunk to insignificance in the face of high costs and acknowledged limitations in manufacture. To charge that this industry is built upon a structure of assumption, psychology, and improperly weighed evidence is an impeachment of the integrity or belittling of the powers of observation of users through many centuries of service experiences.

Jan 1, 1929

By B. A. Rogers

The etching effect that is produced on a piece of polished iron or steel when it is heated in hydrogen or in a vacuum seems to have been observed first by Osmond,' who believed that he could distinguish four systems of grain boundaries on a piece of steel which had been heated in hydrogen. In a number of other investigations, samples of pure iron were found, after heating, to have complex networks in which two or three systems of grain boundaries could be detected. It was further noticed that samples that had been polished plane before being placed in the furnace were, after treatment, roughened and undulating over their entire surfaces. From a comparison of the temperature of heat treatment with that of the A3 transformation, it was concluded that the changed appearance of the samples was definitely related to the latter phenomenon. Certain other deductions were made but these are not of importance here and only observations on the appearance of the samples will be reviewed. Ewen2 heated a strip of polished iron in a vacuum in such a way that one end was maintained at a temperature of 1000" C. and the other at 580" C. On the cooler end there was outlined a simple polyhedral network, and at the hotter there appeared the complex systern of lines ant the undulating surface characteristic of iron which has passed through the A3 transformation. He found that in going from the cooler toward thc hotter end the sample maintained much the same character of surface up to the beginning of the transformed area, but that near this region doublc grain boundaries were of frequent occurrence. Rawdon and Scott concluded that the simple type of network brought out by heating a sample of pure iron in a vacuum was of the same type as that developec by ordinary etching methods. They also confirmed the observations of

Jan 1, 1929

By William H. Shockley

Though China has been widely explored by mining engineers during the past dozen years, comparatively little has been published concerning its mineral resources. The few moilographs scattered through the transactions of various societies contain far less information than the private reports made to the numerous syndicates which have sent out engineers. The best general account of the geolopy and mineral resources of China is to be found in the works of von Richthofen,' a remarkably gifted observer. The observations recorded here in this paper were made in the service of the Pekin Syndicate (which has kindly given me permission to publish them), during the first months of 1898, among the coal- and iron-fields of southeastern Shansi. This is one of the largest anthracite-regions known, the area being

Jan 1, 1904