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By Paul M. Tyler, Oliver Bowles

The extensive employment of nonmetallic minerals antedates the use of metals, but only within the last two decades has the production of nonmetals begun actually to keep pace with the complicated activities which characterize the so-called Machine Age. The economic changes ushered in by the Industrial Revolution were reflected first in an increased demand for metals and for fuels. In the modern sense, therefore, the nonmetallic mineral industries are new and afford new opportunities for engineer and economist alike. A certain amount of caution is indicated, therefore, before attempting to apply ready-made formulas to the problems of these industries. Economics is not an exact science. In the field of production technology where the number of variables is fairly well known, the principles of economics are readily applicable, but as the student proceeds through the province of marketing into the unexplored regions of psychology and sociology he must distinguish carefully between scientific reasoning and purely metaphysical speculation, even when the latter masquerades as economics. The present paper attempts to prove no preconceived theorems and is designed primarily to stimulate careful thinking on sundry neglected phases of these industries. An attempt is made to differentiate the general problems into single aspects which afford promise of being comprehended separately; also, some fundamental statistical data are presented, but merely to indicate a method of scientific approach applicable to more intensive studies. Definition Before discussing the economics of the nonmetallic mineral industries, it is appropriate to consider what we mean when we say "nonmetallic minerals." This term, inasmuch as it is merely a negative description, is somewhat loose and ambiguous and gives rise to questions in regard to minerals that, like chromite or bauxite, are alternatively classed either as nonmetallic or as metallic minerals (or ores). The chrome ore used to make ferrochrome for steel manufacture is undoubtedly metallic in character; similar material destined for use as a refractory in the same

Jan 1, 1934

By M. D. Hassialis, A. F. Taggart

ark' observed some years ago that collector-coating reactions with xanthates and with fatty acids clearly follow paths parallel to those prescribed by the familiar mass-action law for reactions in dilute solutions. He proposed, therefore, the logical hypothesis that they are governed by the solubility-product principle. However, he went astray in the application of his proposal to collector coating by overlooking the fact that coating involves a heterogeneous reaction. A mistaken concept of the meaning of the word adsorption also entered. Wark thought that the concentration of metallic ion that must be used in setting up the solubility-product equation for the coating reaction was that which could be obtained by solution of the mineral. Since this is very low for sulphide ores, and since the amount of the collector ion necessary for coating produces an extremely low concentration, the resulting ion-concentration product, under conditions when coating occurs, is much lower than that which would indicate a saturated solution of the collector-coating compound. Hence he was forced to the position that the solubility product governing the coating is much smaller than the standard solubility product. To justify this position it was necessary to postulate a coating mechanism that did not obey the ordinary laws of chemical reaction. This Wark did by adopting the concept that adsorption is a property of matter, rather than merely a more or less ephemeral local concentration thereof. Thus he says (p. 142 of ref. I): "Adsorption is not a purely physical property of the solid surface, for the specific nature of the adsorbed molecule or ion is important." The result was that he destroyed the great potential utility of his postulate by tying it to this erroneous concept in the words (pp. 142, 143): "It will be obvious that the adsorption solubility product is less than the normal solubility product." The writers have found quantitatively in the case of galena and potassium ethyl xanthate, and semiquantitatively in the case of covellite and the same collector, that the coating reaction does follow the mass-action law to the extent that coating occurs when the ordinary solubility product of the coating compound is exceeded, and that coating does not take place under the reverse conditions. In the course of the investigation leading to the establishment of this fact it was necessary to work with xanthate concentrations so low (down to 0.0004 mg. per liter), that very long conditioning times, and bubble-contact times of as much as 16 hr. were necessary sometimes to follow the reactions. The results have led to some illuminating conclusions as to necessary collector concentrations in normal flotation operations, and the action of the frothing agent in connection therewith' The experimental work comprised accurate determination of the standard solubility product of lead ethyl xanthate, development of a much less laborious

Jan 1, 1947

By James S. Browning

The Bureau of Mines conducted laboratory and small-scale continuous tests of kyanite ore from Georgia and South Carolina to determine the technical feasibility of recovering commercial grade kyanite concentrates by flotation. The research indicated that combinations if sulfuric acid and petroleum sulfonate may be used effectively for flotation of kyanite from quartzite-kyanite ore. This report summarizes the results of these tests, and demonstrates the feasibility of producing commercial-grade concentrates with a high recovery of the contained kyanite. Extensive deposits of kyanite occur in the southeastern United States. The reserves of these deposits, if developed, are adequate to supply the United States with 35-mesh kyanite concentrate for many years at the present rate of consumption. According to Espenshade and Potter,' the kyanite-quartz rock type deposits in this area contain about 100 million tons of ore averaging 10 to 30% kyanite. The tonnage of kyanite-bearing gneiss and schist is much larger than the tonnage of kyanite-quartz rock, but the kyanite gneiss and schist are appreciably lower in grade. The largest deposits of kyanite-quartz rock are in the Farmville district, Virginia, and Kings Mountain district, North Carolina-South Carolina, and at Graves Mountain, Ga. Of the known deposits, only four were being mined for kyanite in 1 967. These deposits are near Farmville and Dillwyn, Va., Clover, S.C., and Washington, Ga.

Jan 1, 1970

Edgar Archibald Collins was born at Truro, Cornwall, Nov. 16; 1877. He was the fifth (and youngest) son of J. H. Collins, a well known Cornish geologist and engineer, who died in 1916. Edgar Collins spent part of his childhood at Rio Tinto, in Spain, and after returning to England was educated at Alleyne's School at Dulwich, near London. His technical training was acquired by practical experience in Cornwall, supplemented by private study and by his father's teaching. This method of training for the work of a mining engineer was preferred by his father to that of the technical schools then available, and judging by its result, was not unsuccessful. It is,-however, noteworthy that all members of the Collins family who were products of this system later sent, or planned to send, their own sons to technical schools. Edgar Collins came to Gilpin County, Colorado, in 1894, and returned there in 1898, after several intermediate years spent in Cornwall. In Colorado he worked, under his brother Arthur, in the California and other mines of the Gilpin County district, and thereby gained a practical skill and experience as a working miner, and a habit of minute observation of vein phenomena, which proved of the greatest value in later years. In 1899 he went to the Smuggler-Union it Telluride, as general assistant to his brother Arthur, and stood the brunt of 3 years of struggle with the Western Federation, gaining a reputation, for quiet courage and sound work under the most difficult conditions. After Arthur Collins' assassination in the Smuggler-Union office, in November, 1902, Edgar left Telluride, and shortly thereafter entered the employment of a syndicate headed by Arthur Winslow, of Boston, to search for and develop new mines. While so engaged he spent several unsuccessful months near Parral, in Mexico, and later visited and sampled the- newly discovered district of Grandpa, afterward known as Goldfield, in Nevada. This led to the acquisition by the Winslow syndicate of the Combination mine, at first under lease and option; and Edgar Collins was placed in charge. The Combination was really the starting point of Goldfield. It was a profitable mine before the discoveries at the Jumbo were made; and while the Combination, being a "Company-account" mine, controlled by a few responsible men, never attracted the publicity that centered around the sensationally profitable leases on the Jumbo and Mohawk, which publicity was used to further the feverish stock-dealings that characterized the new district. The Combination was really the pioneer mine, made the first shipments of rich ore, constructed the first water-line, and built the first mill (designed by F. L. Bosqui, an old friend and associate); and while it pursued a quiet and unobtrusive. career up to the time of its sale to and incorporation with the Goldfield Consolidated, was probably, in ;proportion to the amount of money risked, the most profitable bonanza in the recent history of gold mining.

Jan 11, 1918

By B. N. Das, H. E. LaBelle, G. A. Wolf

ZnxHg1-xTe and GUPxAS1-x crystals have been grown from solution by a traveling heater method (THM). In a floating zone type fashion a solution zone sandwich of liquidus composition is made to migrate through feed material of solidus composition by a slow-speed movement of <0.25 mm per hr of the total charge through a stationary radiation or rf heater. ZnxHg1-xTe of composition 0 < x < 0.3 and GUPxAS1-x of composition 0.5 < x < 0.7 have thus been grown from their solution in liquid tellurium and gallium, respectively. A simplified analysis of heat and material transport is given. In this method, Proper adjustment of the temperature distribution along the liquid solution zone axis eliminates instability of the crystal growth front and constitutional supercooling. 1) ZnxHg1—xTe: The solid-solution telluride was grown in sealed quartz tubes at a temperature of 500 to 650°C. For first Preparations mechanical mixtures SINGLE crystals of solid solutions of III-V and II-VI compounds have been grown by various techniques from the melt, from the gaseous phase, or from solutions in of ZnTe and HgTe were used. X-ray determinations showed the resulting crystals to be homogeneous throughout their entire length, except for the end sections. The homogeneity is greatly improved by reusing the ingots obtained from first Preparations as feed material in subsequent crystal growth runs. Ingots of up to 4.5 cm have thus been obtained. 2) GaPxAs1-x: Crystals were grown in a EN crucible at a temperature of 1050°C. For first Preparation a mechanical mixture of Gap and GaAs was cemented together by a minimum amount of liquid gallium through "wet" grinding of Gap and GaAs crystals in the liquid metal and subsequent exuding of excess gallium by compacting of the charge in the EN crucible. Electron microprobe measurements using P-Ka and As-Ka radiation showed uniformity over a length of 0.4 cm. Properties of the various Preparations are described. liquid metals.&apos;-&apos; Their growth from the melt by passing a liquid zone of pseudobinary liquidus composition through a solid rod of solidus composition is generally a convenient method of growth of single crystals of solid solutions of homogeneous composition. This method loses much of its usefulness, however, if the melting point or the vapor pressure of the solid solution is high. In the case of a compound having a high melting

Jan 1, 1969

By A. A. Collins

OF widespread interest to all lead metallurgists is a dross smelting process that will consistently give mattes and speiss of low lead and high copper contents. It is a problem that has intrigued operators through the years. In the past few years, with increased amounts of copper and overcrowded metallurgical furnaces, it has been almost imperative to evolve some method. Experience at El Paso has shown that high copper-to-lead ratios can be consistently attained by use of the new soda process. † Older Methods Three older methods, i.e., 1. Dross plus siliceous ore and limestone. 2. Dross plus one fourth blast-furnace speiss and siliceous ore, 3. Dross plus sulphides and siliceous ore and scrap iron, do not give consistent results and the products are higher in lead and lower in copper than those produced with the soda process. Any radical changes in the blast-furnace drosses will throw any of these older methods into a tailspin. For almost ten years, El Paso used the third method, with varying results. It was noted that as the arsenic and anti- mony contents of the dross increased, the speiss and matte steadily increased in lead and decreased in copper. A dross containing four parts of copper to one part of arsenic was considered to be ideal. At times this balance of copper to arsenic was almost impossible to obtain, especially when handling copper Cottrell dusts, which vary so greatly in copper and arsenic. Custom smelters like El Paso, handling a great variety of dusts, concentrates and ores, are apt to have anywhere from I to 15 pct copper on charge, with a variable in arsenic of from 0.5 to 2 pct. With such conditions, and drosses varying from 12 to 40 pct copper, an operator using the older dross reverberatory practices would find it just about impossible to control the reverberatory operations and to produce a good product low in lead and high in copper. These conditions prevailed at El Paso from the year 1940 to the present. In May 1942 it was decided to experiment with the soda process. The Soda Process After considerable work the soda method was finally evolved to the present state. It has never failed to produce a good product even under the most adverse conditions. It might be well to remember that many men of thought in the smelting industry have at one time or other sugge~ted the removal of all copper, arsenic and antimony from the lead blast-furnace charge as an aid to better metallurgy.

Jan 1, 1949

By Walter R. Hibbard, Cyril Stanley Smith

IN 1929 one of the authors&apos; determined the constitution of copper-silicon-manganese alloys containing over 90 per cent copper. Through a combination of circumstances the presence of the copper-silicon kappa phase was overlooked in both binary and ternary systems. In the binary system the omission has already been rectified.2,3 To establish the limits of this phase in the ternary system, the samples that had been heat-treated at the time of the original research have now been re-examined, using more careful technique. Full details of the compositions used and the temperatures and times of heat-treatment are to be found in the earlier paper .2 The etching reagent now used to distinguish the kappa phase had the following composition: hydrogen peroxide (30 vol.), 20 c.c.; water, 25 c.c.; 20 per cent potassium hydroxide solution, 5 c.c.; ammonium hydroxide (0.90 sp. gr.), 50 c.c. Table I lists the newly observed structures. In virtually every case the constituents are the same as those previously recorded, except where kappa is now shown to be present as a result of the improved etching technique. A few other changes will be noted (No. 138 at 450°C., No. 149 at 550°C., Nos. 153 and 149 at 750°C.). The change from liquid to beta in equilibrium with kappa in No. 139 at 800°C. is based upon newly heat-treated samples. The alloy is very near the solidus at 800°C. and probably there was a slight error in the old heat-treatment temperature. The isothermal phase diagrams shown in Figs. 1 to 6 were reconstructed on the basis of the new studies. The presence of manganese does not greatly change the composition limits of the kappa phase or cause the [K = a + ?] change to occur at a markedly different temperature. There is some uncertainty regarding the range of existence of beta, for alloys were not spaced very closely in composition. The proposed diagrams, however, are in accordance with the available experimental data and with the dictates of the phase rule. Theoretically necessary fields with no experimental points are delineated by dotted lines. The alpha boundaries at all temperatures are shown together in Fig. 7. This includes also some additional points on the alpha boundary at 300° and 350°C., which were obtained as a result of electrical-conductivity measurements. Two series of seven alloys with increasing manganese content but with silicon constant at 1.90 ± 0.03 per cent or 2.42 ± 0.05 per cent were cast in ingots of 3-in, diameter. These were hot-rolled, homogenized and drawn to wire, finished at 0.08-in. diameter with a 61 per cent reduction of area following annealing at 900°C. Conductivity determinations were made before and after annealing for 30 days at 300°C. or 21 days at 350°C. Figs. 8 and 9 show the change of conductivity produced by this annealing, plotted against manganese

Jan 1, 1942

By Alan Morris

The investigation of the hot-working properties of metals and alloys furnishes a problem which has been attacked in many ways. Tensile, impact and hardness tests on heated specimens have furnished interesting data, but in most cases either the tests are difficult to make or the results hard to translate into terms of practical value. Some investigators have used the drop hammer to advantage. It furnishes a rapid and simple method of comparing the plasticity of metals at elevated temperatures. The indications obtained by its use are of value only in so far as their significance is understood and they can be intelligently used to predict the behavior of a given metal under given hot-working conditions. The work reported here was undertaken not only to add something to the existing volume of such data but also to contribute to our understanding of the results. Doerinckel and Trockels1 used cylindrical specimens and determined the work required to reduce the specimen to one-half the original height. Ellis2 studied the effect of constitution on the malleability of steel at high temperature. His method and that of Kent3 were similar to the one used in the present work. The tests described by Kent were made on samples of tin, zinc, aluminum, copper, lead, 70:30 and 60:40 brasses, with and without a small quantity of lead. He concluded that the test would "indicate whether a material can be forged at a given temperature without cracking." This interpretation must be used with caution. While it is probably true within limits, one must consider the severity of the forging operation. Again, it will not apply strictly to forms of hot working other than forging. For instance, an alloy running 61.0 per cent. copper, 3.25 per cent. lead, remainder zinc, will crack badly in the test, yet, it is extruded commercially. When the possibility of hot-working a new alloy is being considered a study of its drop-hammer test should help

Jan 1, 1931

By Ralph J. Schilthuis, William Hurst

The nature of the forces that are important in producing the oil in the East Texas field and the manner in which these forces are affected by the rate of production have always been problems of outstanding interest. These questions are of great interest to the industry as a whole on account of the economic importance of the East Texas field and to the engineers in particular on account of the unique character and behavior of the field. Subsurface pressure data throughout the field have been collected systematically, so that a quite complete history of the reservoir pressures has been kept as the field has been developed and produced. Subsurface samples of the oil and gas have been taken and these have been examined to obtain data on the physical properties of the reservoir fluids under the actual conditions of temperature and pressure. All of these data have been valuable because they have afforded the basis for a careful study of the means by which the oil is produced. It is the purpose of this discussion first to point out several of the important facts revealed by the data mentioned and then to describe studies that have been made concerning the interpretation of these facts. Reservoir Pressure Data and Properties of Oil The reservoir pressure data on the East Texas field have shown conclusively that the pressures are readily affected by changes in the rate at which the field is produced. This can well be seen in Fig. 1, where the average reservoir pressures obtained from time to time are plotted with the daily production rates and the cumulative production of the field. It is noted that the average reservoir pressure has declined irregularly, depending upon the rate of production, from the estimated original value of 1625 Ib. per sq. in. to the value of 1228 lb. per sq. in. observed for Aug. 11,1934. The decline in pressure has been more rapid at the higher rates of production than at the lower rates. In contrast, the average reservoir pressure has increased, on several occasions, upon reduction of the withdrawal rate from a high value to a lower value. The reservoir pressure data have also shown that a definite gradient in pressure has existed across the field from west to east since the begin-

Jan 1, 1935

By W. A. West

ONE who attempts to collect and classify equilibrium data from various iron-alloy systems is soon struck with the absence of any quantitative theory that can serve as a general background against which to compare and contrast results from different systems, at different temperatures, and with different concentrations. It is not necessary to wait for a perfect theory; investigation of divergences of theory from observation may prove of great value in acquiring understanding of the subject. For example, one has only to think of Raoult&apos;s law as applied to aqueous solutions. The equations developed by Zener1 represent an effort to provide such a quantitative theoretical background, and it is therefore desirable to subject this theory to such tests as can be applied. The present article is intended to be an application of available tests, and may thus be considered as a supplement to Zener&apos;s paper. It is assumed that this paper is available to the reader. The equations make it possible to calculate the effect on the equilibrium concentration of one alloying element due to the presence of one or more other elements. In particular they are intended to give, for alloy steels, the carbon concentrations in alpha and gamma phases in equilibrium with each other, and in gamma in equilibrium with cementite. They may, however, be modified for use for carbon-free alloys. A summary is given later of the equations used in analyzing the data in this paper, and the symbols are there defined. About 125 papers have been examined for experimental data suitable for this investigation. An effort was made to look up all available reports of ternary systems including iron and carbon, as well as similar systems of higher order. Supplementary material was also obtained from a number of binary systems. A few noncarbon ternary systems were also found to which these methods could be applied. A comparatively small proportion of the papers read provided usable material. In many systems the number of quantitative observations made in the iron-rich region is extremely small, and the smoothed curves to be found in most published phase diagrams are entirely useless for quantitative treatment. This opinion is confirmed by the authors of the series on Alloys of Iron Research, whose remarks show clearly that they have no illusions as to the accuracy of many diagrams that they present. A further difficulty arises from the fact that these equations apply only to rather low percentages of alloying elements. The result is that at the lowest concentrations, where the best agreement might be hoped for, the errors of observation become relatively very large. The experimental difficulties in measurements of this kind of equilibrium are, of course, an old story.

Jan 1, 1946

[A session of the Institute of Metals held during the February, 1926, meeting of the Institute, was devoted to a symposium on &apos;&apos;gas" in copper. S. Skowronski, Perth Amboy, N. J., was chairman. On the program were papers by T. S. Fuller; W. H. Bassett and J. C. Bradley; Susan B. Leiter, and W. H. Bassett and H. A. Redworth. These papers follow the chairman&apos;s introductory discussion.] S. Skowronski, Perth Amboy, N. J.—There are today two groups of metallurgists, one group who believe in oxygen-free copper and another group who believe that oxygen is absolutely essential in copper; not that the two groups disagree, but that a certain grade of work calls for oxygen-free copper, while another grade of work does not. I can sum up the problem by reading the abstract of an article by Frederick Johnson of Great Britain in The Metal Industry of Sept. 4, 1925. Few, who have watched the trend of things during the last two decades, can have failed to notice the steady growth of opposition to the prevalent use of copper in the "tough-pitch" condition, which for many ages enjoyed an unchallenged supremacy. Broadly speaking, there are two schools of thought in the metallurgical world, one holding the view that copper containing a small proportion of oxygen is an eminently suitable material for users, the other expressing its preference, in no hesitating or uncertain manner, for copper from which oxygen has been removed by means of a deoxidizer. In the old days, before the advent of the converter and the electrolytic refining process, the copper of commerce was so impure that the presence of oxygen was imperative in order to neutralize the influence of impurities which militated against the hot-working properties of the metal. For electrical purposes, oxygen must be present, because sound bars and billets cannot be produced without it, except at the expense of electrical conductivity. For most engineering purposes, however, electro-deposited copper may be used either by itself or with the addition of alloying elements, e. g., arsenic and nickel, which experience has proved to be beneficial, such copper being freed from oxygen by the aid of a deoxidizer, e. g., phosphorus. Such material has positive advantages over "tough-pitch" copper as at present produced from refinery furnaces. It has greater toughness and malleability, and is immune from the action of reducing gases at high temperatures, the destructive action of which, in the case of "tough-pitch" copper, is well known. The reasons why there has been no wholesale replacement of "tough-pitch" copper by deoxidized copper are commercial in nature; copper can be more economically melted in large-capacity furnaces which lend themselves to the poling process and are not so suitable for control of uniformity of action of deoxidizers as the smaller electric or crucible furnaces, whilst they are also more convenient for the production of very large castings. Moreover, the equipment of most large copper manufacturing plants is designed for casting "tough-pitch " copper in open moulds, e. g., wire bars and cakes, and these could not be used for deoxidized copper, which must be cast in vertical moulds as in brass-shop practice. Further, there are still certain impure brands and

Jan 1, 1926

By R. W. Waterfill

MANY existing ore deposits of valuable metals have been worked out in their upper surface levels and the continued productivity of these mines is dependent on their extension to greater depths in the earth. The maximum depths at present reached are about 6000 to 8000 ft. below the surface, with no evidence of an impoverished ore vein. These mines are widely distributed; some of the best known are in South Africa, Brazil, India and in the western sections of the United States. Among the factors which increase the difficulty of working these mines at increasing depths are hoisting, rock pressure and temperature. The manner and effectiveness with which these problems arc met will, no doubt, determine in a large measure the ultimate depths to which any mine can be profitably worked. The most critical of these three factors at present is the increase in temperature with depth. The high temperature and humidity in many of these mines at present are severely detrimental to the health of the workers and greatly hamper their efficiency. Some have almost reached a condition in which the human system cannot survive. The problems involved in the cooling and ventilation of mines have all been ably analyzed and presented in previous articles. For this reason, only a résumé of conditions affecting the cooling and conditioning of deep and hot mines will be given in this paper before attention is directed to possible methods of improving atmospheric conditions in the working levels. Physiological Effects of Temperature, Humidity and Air Motion Many data on the physiological effects of different atmospheric conditions on the human system have been compiled and published through the combined efforts of the American Society of Heating and Ventilating Engineers, the U. S. Bureau of Mines and U. S. Public Health Service. These data were not primarily developed around the conditions existing in deep mines, but the upper temperature limits of the investigations extend into, and are applicable to, mine atmospheric conditions. While the exact values of the standard comfort conditions, established for persons of such habits as those employed in detecting the different degrees of comfort, might not produce identical effects upon persons inured to

Jan 1, 1929

By O. Katz, A. Spilners, M. Simnad

THE oxidation of titanium has been studied in recent years by a number of investigators.&apos;-W ne of the most important aspects of the reaction of titanium with oxygen, which has been observed by several of the investigators, is the extremely high solubility of oxygen in the metal. A detailed study of the Ti-0 systeml% as shown that the solubility limit of oxygen in a-titanium is approximately 14.5 wt pct 0 from 800" to 1700°C. The unusual oxidation behavior of titanium may be ascribed to this phenomenon, since part of the oxygen uptake enters into solid solution in the metal and only a part is available for scale formation. A more complete study of the kinetics of oxidation of titanium would require information on the influence of oxygen in solution in the metal upon the oxidation rate. Such information would also be of interest in regard to the theory of oxidation of metals. The authors have measured the oxidation rates of oxygen-saturated and oxygen-free titanium between 800" and 1200°C and have found appreciable differences in their rates of oxygen uptake and in the activation energies. The experimental set-up was similar to that described in a previous paper.u The course of oxida-dation was followed continously by attaching the specimen to a sensitive spring balance and observing the extension of the spring with time of oxidation. High purity electrolytic oxygen was used and precautions were taken to purify the gases employed. The specimens were prepared from iodide titanium and were ground on metallographic polishing papers to a fineness of 4/0. The furnace was first evacuated and filled with argon; the specimen was lowered into the furnace, which was then evacuated and filled with oxygen, after the specimen had reached the oxidation temperature in argon. The samples were presaturated with oxygen by means of the following procedure: Each specimen was first heated in oxygen at 1200°C until its increase in weight indicated 13.8 pct by weight uptake of oxygen. The furnace was then immediately evacuated and filled with purified argon five times. The specimen was heated in the argon atmosphere for a period of 72 hr at 1200°C in order to saturate the metal with oxygen by complete absorption of the scale. The temperature was lowered to the oxidation temperature, the furnace was evacuated and filled with oxygen, and the oxidation rate was followed by noting the extension of the spring balance. No oxide film was visible on these specimens at the start of the oxidation experiments. Titanium samples in the oxygen-free as-received condition were also oxidized and their oxidation rates measured. The results are shown in Figs. 1, 2, and 3, which indicate that the initial rates of uptake of oxygen by both the oxygen-saturated and oxygen-free specimens are parabolic at these temperatures. The rate of uptake of oxygen is, however, appreciably lower

Jan 1, 1956

By D. S. Eppelsheimer, D. N. Williams

The compression texture of iodide titanium is determined and found to consist of a [0001] texture rotated 15° to 30° from the axis of compression. As the amount of reduction increases, the angle of rotation decreases. The 0001 rotation showed a slight preference for a <1010> rotation axis. RECENT investigation of the cold rolled texture of titanium&apos; has shown this metal to exhibit a new type of rolling texture. This texture can best be described as a (0001) [10i0] with the 0001 planes rotated approximately 30" to the transverse direction around a <10i0> rotation axis. Rather good results in explaining the cold rolled texture have been obtained by other workers&apos; by examination of the tension and compression textures. No information was found giving the tension texture of titanium. Generally the tension texture of a hexagonal close-packed metal is identical with its wire texture. The drawn texture of titanium has been investigatedh nd has been found to be predominately [10?0]. Since this is the common tension texture of hexagonal metals of low c/a ratio, the explanation of the difference between the rolling texture of titanium and the rolling texture of other hexagonal metals is not indicated by examination of the tension texture. Therefore, the compression texture of titanium should be particularly important in the explanation of the unusual transverse rotation of the 0001 planes found in the cold rolled texture. The compression texture of titanium was examined by Yen.",&apos; His results showed titanium to exhibit the usual [0001] texture up to 85 pct reduction. At higher reduction a double texture appeared in which the 0001 planes were rotated from 10" to 30" from the plane of compression. This change in the compression texture seemed unusual since the tendency for hexagonal close-packed metals is to approach the [0001] texture as the idea compression texture. Mechanical twinning generally occurs over a considerable range of reductions beginning at a rather low reduction. The samples used by Yen in his investigations were prepared by two methods. Compression in a testing machine was used up to a reduction of 85 pct. Compression by compression rolling was used at higher reductions. Since the change in texture occurred at the same reduction as the change in the method of compression, a connection between the two seemed likely. To check this possibility and to locate the position of the change in texture definitely, if it was found to exist, the compression texture of titanium was re-examined. An iodide titanium crystal bar (99.9 pct Ti) produced by the New Jersey Zinc Co. and donated by the Titanium Alloy Manufacturing Div. of the National Lead Co. was used in this investigation. Procedure The investigation of the compression texture was carried out in three steps; compression, specimen

Jan 1, 1953

By Frederic Lahee

THE total production of crude oil in Texas during 1924 was said to be 133,613,985 bbl. as compared with 125,991,628 bbl. in 1923.1 Subtracting from these figures the yield of the Gulf Coast fields, there remains, for the other part. of Texas, a yield of 106,272,573 bbl. in 1924, as compared with 101,931,595 bbl. in 1923. This represents an increased, production of over 4,250,000 bbl. for all of Texas outside of the Gulf Coast or Salt Dome fields. Within this same region, in 1924, there were 3624 completions, of which 2352 were oil or oil and gas wells, 7 were gassers, and 1265 were dry holes. Thus, nearly 35 per cent. of the completions were dry holes. In 1923, there were 4134 completions, with 2853 oil or oil and gas wells, 2 gas wells, and 1279, or 31 per cent. of the total, dry holes. Outside of the Gulf Coast region, six major pools were discovered and developed in 1924.; two pools, previously discovered, were extended far beyond their limits at the end of 1923, and many smaller pools were opened. The major pools were the Big Lake field, in Reagan Co., the New Richland field, in Navarro Co., the Harmel, Carey, and Ragle pools, in south Archer County, and the Wortham field, in Freestone and Limestone Counties. Fields that were notably extended were the Panhandle producing area and the Luling field. Many wildcat wells have been drilled; most -of these were failures, but several opened .pools and several have had sufficiently favorable results to. lead to further drilling. The activity of the operators in searching for new production was very intense during 1924, and indications point to as feverish a campaign during the coming year. This will be stimulated by rising prices for crude oil. There are good reasons for believing that new pools will be discovered along the Mexia fault zone, in Archer, Young, Baylor, and Throckmorton Counties, in the great central region of Texas where we now have the Mitchell County and Reagan County pools, and very likely in the eastern Red River Counties including Cooke and Grayson. On the other hand, with the opening of the year, there is no new big pool in sight. An outstanding feature of the production end of the business is the increasing reliance placed on geological work and geological recommendations. Not in five or six years has there been such a demand for first-class geologists.

Jan 3, 1925

By F. C. Sturges

FOR some time mining engineers have been interested in the possibility of using small diameter shafts, sunk by core drilling, as aids to ventilation and as emergency escapeways. The possibilities are interesting to contemplate, but new methods involve unknowns, and interest tends to remain passive until these unknowns are solved. Recently we have completed two 36-in. diam. core drilled shafts, and wish to make the data on these available to the industry. Both shafts were drilled for the McLain Fire Brick Co., one at its Buckeye mine and the other at its Colonial mine. Both mines are in the fireclay underlying the Lower Kittanning coal. Both mines have been in operation for a number of years [ ] and have required expensive maintenance work on return airways. It was decided that considerable savings could be effected by short-circuiting the air to the surface through small shafts. It was also realized that these holes, located near the present workings, would be of added value as emergency escapeways. Originally, 48-in. diam. shafts were considered, but actual computations showed 36-in. diam. shafts were more than ample at both mines. The shaft at the Buckeye mine is 240 ft deep, and that at the Colonial mine 258 ft deep. Both holes were started in the lower part of the Conemaugh formation and penetrated Conemaugh and Allegheny strata. The holes were started through the unconsolidated materials overlying bedrock by constructing a concrete collar with a wall thickness of 8 in. Then the shafts were drilled by the shot-core drill method. An annular groove was cut in the rock by the abrading action of chilled steel shot run under the shoe of the core barrel. The drilling was done in stages, the core barrel drilling the groove for a certain distance depending on conditions encountered, and then the cores broken off and taken out in sections. The core barrel had a 36-in. o.d. and the finished diameter of the shaft measured almost 37 in. The major questions that could not be answered until the completion of the first shaft were, (I) how much ground water would be encountered, how would it hinder the drilling, and how difficult would it be to seal off, and, (2) how would the walls of the hole stand up. The holes of course could be cased or lined, but that is considerable added expense in any shaft.

Jan 1, 1947

By William J. McCaughey, Richard L. Barrett

FOR sixty years-in fact, ever since the inception of the basic steelmaking process -basic slags have been the subject of study by chemists, metallurgists and petrographers, with the purpose of providing a better understanding of the reactions between the slag and the metal during the refining process. The result of this work and of the researches of mineralogists and physical chemists into the chemistry of oxide systems is a considerable body of literature dealing not only with slags themselves but with equilibrium relationships in systems synthesized from pure components. Since any actual slag is a multicomponent system more complex than any yet worked out in the laboratory, a complete solution to the problem is still far away. The writers have recently published a paper1 which they believe sheds light on the role of the slag in the elimination of phosphorus and it is the purpose of the present paper to discuss the metallurgical applications of that work. Since the pioneer investigations on the constitution of basic slags carried on by Stead and Risdale, Carnot and Richards, Hilgenstock and others in the 1880&apos;s, a considerable body of literature on this subject has appeared. Many of the more important of these papers were summarized in the previous paper,&apos; therefore they will not be reviewed here. PETROGRAPHIC STUDY The present writers have had occasion, over a period of years, to examine petrographically a great number of basic steel- making slags having a very wide range of chemical compositions and made under various conditions of operating practice. Although certain of these slags exhibit some unusual features, it is a remarkable fact that the great majority of mature slags show certain typical characteristics, which persist throughout the wide range of chemical compositions. The typical mature slag usually appears under the microscope to consist of two phases. The phase of primary crystallization is light colored and doubly refracting. If separated mechanically and subjected to chemical analysis, it is found to consist essentially of SiO2, CaO, and P2O5. Sometimes, although not usually, two such silicate-phosphate phases are found. The other conspicuous phase is dark in color and optically isotropic, and occurs as the interstitial material between the grains of the light colored phase. This dark colored interstitial phase when analyzed is found to consist essentially of FeO,Fe2O3, MnO, and MgO. In some slags high in iron oxide, particularly those from low-carbon heats, dicalcium ferrite is found. This phase is dark reddish brown in color and anisotropic.

Jan 1, 1944

By M. E. Wadsworth, I. B. Cutler, R. W. Bartlett

The oxidation kinetics of ZrC was studied between 450" and 580°C in oxygen pressures from 6.5 x 10-to 1 atm using a ther mogravimetric apparatus and sized powder samples. Two parallel rate controlling processes were observed. A surface reaction occurring at the ZrC-ZrO2 phase boundary accounted for most of the oxidation and had an activation enthalpy of 46 kcal per mole. The other process, believed to be diffusion of oxygen into the ZrC lattice partially replacing carbon, had an activation enthalpy of 53 kcal per mole. The enthalpy for chemisorption of O2 on ZrC was determined to be —13 kcal per mole. Water vapor in the presence of oxygen accelerated the surface reaction rate. THERE has been little reporting of formal rate studies or attempts to ascertain the mechanism of oxidation of carbides. MacDonald and Ransley1 studied the oxidation of titanium carbide which has the same structure as zirconium carbide, fcc. They observed an initial increase in rate with increasing temperature followed by a rapid decrease through a rate minimum and a subsequent second increase at higher temperatures. The discontinuity in the rate rise was attributed to a phase change in the oxide which changed the rate determining step from the surface reaction at the carbide-oxide interface to diffusion through the oxide layer. Samsonov and Golybera 2 studied titanium carbide and reported that during the initial period of oxidation a dense film of Tic-TiO was formed followed by the formation of less adhering layers of higher oxides. The purpose of this investigation was to study the kinetics of oxidation of zirconium carbide and to attempt to gain some knowledge of the mechanism by which oxidation occurs. EXPERIMENTAL PROCEDURE Measurement of the weight gain associated with the oxidation of ZrC was used to determine oxidation rates. The principal experimental parameters were surface area, temperature, and oxygen pressure. Although moderately sized crystals of ZrC can be grown by the Van Arkel method, the only commercially available ZrC is a powder. In using powders, the surface area must be controlled either by fabricating the powder into a sintered pellet with a measurable surface area, relatively fixed during oxidation, or by using sized unconsolidated powder and applying appropriate geometric considerations to the shape of the grains to correct for their diminishing surface areas as they oxidize. Both techniques involve some difficulties. pellets of binder-free zirconium carbide can be made by hot pressing, but it is difficult to obtain densities greater than 90 pct of

Jan 1, 1963

By C. G. Dunn, F. W. Daniels, M. J. Bolton

J. P. Nielsen—The data that Dr. Dunn and his associates have been obtaining are welcome checks on the theoretical aspects of grain boundary energies. With reference to the comments on the validity of the inter-facial tension concept, I should like to say that I have been having considerable difficulty myself in untangling the confusion between "interfacial tension" and "interfacial energy." The confusion however resolved itself for me when I learned that "interfacial tension" for solids, or at least crystals, is used with two distinct meanings. One meaning12. &apos; "hat is implied for "interfacial tension" is the work necessary to produce or increase the surface of the solid in question by a unit area, temperature and pressure held constant. This comes from the somewhat surprising but simple fact that surface tension and surface energy in the case of liquids are identical quantities. This synonymity has carried over to crystals, where it should be kept in mind that the tension connotation has meaning only by analogy with liquids and that no real stresses are being referred to. The only reason that there is apparently a set of stresses acting at a grain boundary junction is the optical illusion that liquid interfaces are being observed for the grain boundaries. The other meaning3,14,15 for the term has to do with actual states of stress in the surface of a material as would be measured by a system of forces applied to the surface to equate the surface stress state with that in the body of the crystal. J. B. Hess—Since the authors have proposed that the surface tension concept should be discarded in order to deal with the general case of interface energies in solids, their attention should be called to a recent paper by Gurney." The latter has shown, from a thermodynamic argument, that surface tension is a valid concept in solids. In fact, Gurney has rejected the idea that surface tensions are merely mathematical fiction and, instead, has given an interpretation of their physical reality. Finally, he has concluded that, as long as appreciable atomic migration takes place, specific surface energies and surface tensions must be equivalent in solids as well as in liquids. Accordingly, the authors&apos; eqs 2 and 3 can be written with equal accuracy in terms of interface tensions, simply by replacing each E,! with its numerically and dimension-ally equivalent Interfacial tension ?,,. If the interfacial tensions (or specific energies) are independent of interfacial orientation, as is true in liquids, then the general equations that define the geometry at equilibrium of the common junction of three interfaces reduce to eq 1. However, neglect of the effect of boundary orientation is never completely justified theoretically&apos; in dealing with crystalline solids; hence, use of eq 1 in such cases must always be considered as an approximation, though clearly a reasonable one for many purposes.1,2 At the same time, one should not be surprised that the assumption that interface tensions in solids are free from orientation

Jan 1, 1951

By William H. Spice

The year 1942 in the South Central Texas area was marked by a sharp curtailment of exploratory drilling as compared with the past several years. In the 33 counties that compose this district, 17 of which are nonproducing counties, only 51 exploratory wells were drilled during the year 1942. This compares with 118 exploratory wells drilled during 1941, or a decrease of more than 50 per cent. At the end of the year 10 active exploratory wells were drilling in this area, as against 19 being drilled at the end of 1941. Of the exploratory wells drilled, two brought in oil wells and were new field discoveries and one was a gas well extending a recently discovered shallow gas area in the western part of the district. This compares with five new oil fields, one new . gas field and two extension wells drilled in 1941. Both new field discoveries were small and in areas outside of the general trend of the main producing horizon of the district in Edwards limestone: One new field, the Imogene, in Atascosa County, is a deep Edwards limestone prospect at 7500 ft., and the other new field, the Poth, in Wilson County, is a sSEa110w Wilcox (Eocene) prospect at 4000 ft. Subsequent drilling in each field to the end of I942 has proved disappointing. There were no new discoveries along the old Balcones fault-line trend, although 35 of the exploratory wells were drilled in counties along this trend. Approximately 38 wells were drilled in or adjacent to the proven fields of the district, of which 18 were oil wells, 2 were gas wells and 17 were dry holes. The district produced 6,186,178 bbl. of oil during 1942, which was a 7 per cent decrease under production for 1941. Approximately 4,961,000 bbl. of this total production, a slight increase over 1941, was produced by the four Edwards-limestone fields, Luling, Branyon, Salt Flat and Darst Creek, and the rest of the production came from the other 42 active fields in the district. During the year, 20 new producing wells were completed and 221 wells were abandoned in the producing fields. This alarming excess rate of abandonment~ over completions will be further reflected undoubtedly by a further decreased rate of 1943 production under 1942. Two active fields in the district in which more than one producing well was completed during the year were Bee Creek and Washburn. The majority of exploratory work in the district was confined to areas along the Wilcox trend, with a certain amount in progress along the deeper Edwards limestone trend. The successful completion of sevemi wells in the Washburn field from multiple sands in the Lower Wilcor (Eocene) has stimulated exploratory work along this trend, while the completion of a small well in the Imogene field from the Edwards limestone at 7500 ft. has renewed interest in this horizon at depths greater than generally are producing in the district. New Fields ounty. ble Oil and Refining Company&apos;s No. I

Jan 1, 1943