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Jan 1, 1938

By A. U. Seybolt, C. H. Mathewson

As is well known, many questions affecting the properties and uses of a metal cannot be answered without careful consideration of the state of purity realized in the various operations of preparation, refining, or special treatment that have brought the product to its final state. The occurrence of an impurity in minute quantity offers no guarantee that its effect will be inconsiderable because dissolved substances often modify the properties of a metal quite out of proportion to their concentration. In such cases the determination of solid solubility must be accepted as a problem of considerable difficulty, requiring the use of especially purified materials and methods not ordinarily used in the metallurgical laboratory. This aspect of the equilibrium between metals and their oxides is especially important and a search for fundamental data reveals little except conflicting opinion even concerning the systems of common occurrence and interest. Rhines and Mathewson1 in 1934 studied the solubility of oxygen in solid copper by annealing to equilibrium in air and gave reasons for the failure of other methods, notably the ordinary procedure of heat-treatment followed by microscopic examination, to yield reliable results. In this paper, a similar study has been made of the solubility of oxygen in cobalt. The simple theory of this method is outlined below.

Jan 1, 1935

By H. S. Price, J. C. Cavendish, R. S. Varga

A numerical formulation of bigh-order accuracy, based on variational methods, is proposed for the solution of multidimensional diffusion-convection-type equations. Accurate solutions are obtained without the difficulties that standard finite difference approximations present. In addition, tests show that accurate solutions of a one-dimensional problem can be obtained in the neighborhood of a sharp front without the need for a large number of calculations for the entire region of interest. Results using these variational methods are compared with several standard finite difference approximations and with a technique based on the method of characteristics. The variational methods are shown to yield higher accuracies in less computer time. Finally, it is indicated how one can use these attractive features of the variational methods for solving miscible displacement problems in two dimensions. INTRODUCTION The problem of finding suitable numerical approximations for equations describing the transport of heat or mass by diffusion and convection simultaneously has been of interest for some time. Equations of this type, which will be called diffusionconvection equations, arise in describing many diverse physical processes. Of particular interest here is the equation describing the process by which one miscible liquid displaces another liquid in a one-dimensional porous medium. The behavior of such a system is described by the following parabolic partial differential equation:

Jan 1, 1969

By Paul F. Kerr

The insufficiencies of our mineral resources are becoming well known, and the national political conscience seems to be troubled at last by our dependence upon mineral commodities which must come from other lands. This realization places increased responsibility upon the industrial, educational, and governmental groups whose task it will be to solve the problems of mineral supply. As we all know, from the time that man first sought mineral deposits until recent years, prospectors have been largely responsible for mineral discoveries. Today the era of the prospector is almost over. The human ants that have literally examined all accessible outcrops and have tested the gravels of nearly all stream beds in the United States have left undiscovered few worthwhile mineral deposits within the scope of their recognition. The pages in the history of mineral exploration are now being turned from the era of the surface prospect to the era of the hidden de- posit.

Jan 1, 1949

By A. C. Stevenson

IN OUTLINING the various steps taken and the exigences met during the time of unwatering and rebuilding the burnt top equipment at the Hecla mine, the major portion of the detail is omitted and a general description of the experience only is given. All the electrical power lines were out of commission, as were the mine feeder cables. The first effort, there- fore, was to restore electrical connections. The Washington Water Power Co. immediately put a crew to work restoring the power line, it being necessary to rebuild about 4000 ft. of 66,000 volt transmission and about 2000 ft. of 2200 volt feeder. This work was rushed and power was again available at the mine sub- station about 26 hours after the fire. During the same time temporary lighting lines were strung and transformer equipment obtained, so that when electrical connection was resumed the lights were turned on and the dump well lighted that night.

Jan 1, 1924

By E. H. Hamilton

THE furnace on which the following investigation was based had dimensions 48 by 160 in., and was in continuous operation during the three days of the test. The average charge consisted of PER CENT. LB. PER HOUR Bed ore?14.5?2,980 Roast from Dwight-Lloyds?44.5?9,160 Siliceous ore?3.5?720 Iron flux?2.1?430 Battery plates?0.5?103 Lime rock?23.9?4,925 Briquettes?4.0?825 Scrap iron?2.1?430 M. P. slag?4.2?865 L. P.speiss?0.7?142 Total 100.0 THE furnace on which the following investigation was based had dimensions 48 by 160 in., and was in continuous operation during the three days of the test. The average charge consisted of PER CENT. LB. PER HOUR Bed ore?14.5?2,980 Roast from Dwight-Lloyds?44.5?9,160 Siliceous ore?3.5?720 Iron flux?2.1?430 Battery plates?0.5?103 Lime rock?23.9?4,925 Briquettes?4.0?825 Scrap iron?2.1?430 M. P. slag?4.2?865 L. P.speiss?0.7?142 Total?100.0?20,580

Jan 1, 1924

By Bradley Stoughton

A LL over our great country I have been privileged to see, during the last six weeks, the manifestation of a new spirit among engineers. Partly under the inspiration of leaders whose influence has been felt not only nationally, but internationally, - partly through the recognition of the service that engineers have been able to render to the nation during the recent crisis, a new self-consciousness has been acquired by the individuals, and now this self-consciousness seeks expression in opportunities for service and participation in public affairs. The engineer . no longer sees himself a mere reservoir of information to be tapped when some one is in need of cold facts, no. more an administrator of mere material things, but a potential administrator of- public affairs, a citizen and a human being, with the responsibilities, as well as the privileges of citizenship.

Jan 1, 1920

Jan 1, 1880

By Robert E. Goodwin

There are four main requirements to be considered in selecting a wire rope that will provide the best service. A proper choice is made by correctly estimating the relative importance of each of these requirements and choosing a rope with qualities that will best enable it to withstand the combination of destructive forces expected under continued service. A Good Rope Choice Matches Strength with Stress A wire rope should be (1) strong enough to sup- port the maximum load anticipated with a proper safety factor, (2) able to withstand bending and to resist bending fatigue without failure of the wires, (3) able to withstand surface abuse such as abrasion, pounding, and wire scrubbing, and (4) able to take abuse such as crushing and distortion.

Jan 5, 1969

By J. M. GLEDHILL

IT would doubtless have been felt by many but a few years back that there was little left to be said on the subject of crucible tool-steel, and that something akin to finality had been arrived at in its manufacture and general treatment. Probably such feeling was justifiable when it is remembered that the making of steel in crucibles is by far the oldest method known, dating back from time immemorial, it being indeed impossible to accurately trace its origin and earliest development; but it seems certain that carbon-steel was made and used thousands of years ago for cutting-tools. Proof of this may be seen by the marvelous carvings and workings on the intensely hard stone-work of the ancients, for it would be difficult to conceive by what means, other than with steel tools, such work could have been executed; and it is wonderful to contemplate that steel cutting-tools should have been used so long ago, whilst the principle of manufacturing them-that is, by fusion of iron and charcoal in crucibles-was then in a measure on the sane lines as we work on at the present day. Archaeologists have discovered that the Chinese made steel in crucibles long before the Christian era. " Wootz " steel fabricated in India centuries ago was crucible steel, as was also the celebrated Damascus steel, produced at the forges of Toledo, and, curiously, this latter steel furnishes' yet another proof that "There is nothing new under the Sun," for it is recorded that Damascus steel contained certain percentages of tungsten, nickel, manganese, etc., some of the very elements, in fact, contained in the present modern high-speed steel, so that a latent high-speed steel may be said to have existed

Mar 1, 1905

By C. E. Ells, A. Sawatzky

The effect of neutron irradiation on tensile properties of the Zr-2.5 wt pet Nb-0.5 wt pet Cu alloy has been evaluated for integrated neutron fluxes up to 3 x 1020 n per sq cm (E > 1 Mev). Specimen temperature during irradiation was normally 300°C. The material was studied both in annealed and in quenched and aged conditions. When the alloy (fab-ricatedfrom sponge zirconium) is quenched from a temperature =40°C below the a + ß/ß transformation and aged 6 hr at 535oC, neutron irradiation up to the maximum studied has little effect 071 reduction in area, although there is a drop in uniform elongation and the yield strength is increased by = 25 pct. Conversely, irradiation of the alloy in an annealed condition can result in much greater changes in properties, with yield-strength increases of up to 200 pet. The dose dependence of irradiation hardening obeys the saturation equntion proposed by Makin and Minter to explain hardening in copper and nickel: Act = C[1 - exp(-Døt)/1/2 A rnodel is proposed to explain the effect of niobium content and metallurgical condition on irradiatiotz behavior. THE Zr-Nb alloys form a class of material susceptible to marked strengthening by quench and age heat treatment. With niobium concentrations as low as 2.5 wt pet, strengths can be developed which are double those of annealed zircaloy-2.1 Since the neutron-capture cross section of the Zr-2.5 wt pet Nb alloy is nearly identical to that of Zircaloy-2, significant gains in power-reactor neutron economy could be obtained by replacing stressed in-reactor components of Zircaloy-2 with the heat-treated Zr-Nb alloy. When the solution heat-treatment temperature is in the high (a + ß) phase, then the tensile properties of the quenched (and aged at 500°C) material have been shown to be relatively insensitive to neutron irradiation.1-3 Addition of small quantities of copper to the binary Zr-2.5 wt pet Nb alloy gives a useful reduction to the corrosion rate in air and carbon di- oxide,&apos; and a ternary alloy of composition Zr-2.5 wt pet Nb-0.5 wt pet Cu was chosen for one component in the Douglas Point Reactor. This application utilizes both the corrosion resistance to a moist air-carbon dioxide environment and the strength developed by a quench and age heat treatment. By suitable choice of solution heat treatment and aging temperatures, tensile properties of the ternary alloy can be made nearly identical to those considered as optimum for the binary alloy. One effect of the copper addition, however, is to give marked changes in the aging kinetics of the alloy.&apos; For this reason, it appeared that neutron irradiation might promote overaging in the ternary alloy, particularly at the elevated service temperature (=300°C). This paper describes the effect of neutron irradiation on the tensile behavior of the Zr-2.5 wt pet Nb-0.5 wt pet Cu alloy in several metallurgical conditions pertinent to its use as a reactor material. The metallurgical conditions included those for which aging occurs in the unirradiated material, and fully annealed conditions for which a higher degree of thermal stability could be expected. 1) EXPERIMENTAL Two batches of alloy were used, both made from sponge zirconium. The fabricator&apos;s analysis of principle constituents showed no significant difference between the two batches, Table I. The rod material was rolled to 1.5 in. diam, and then swaged to final sizes of 0.5 to 0.375 in. diam at nominal temperatures of 785" and 625°C for the AM and AS batches, respectively. Subsequent hydrogen analyses at CRNL confirmed that the hydrogen concentration of the as-received rod was indeed <20 ppm. However, it was found that the (a + ß)/ß transus for the AM material was approximately 25°C lower than that of the AS material, indicating rather more difference in oxygen concentration than given in Table I. Except for a small difference in yield-point behavior, the tensile prop-

Jan 1, 1965

By F. N. Speller

ASIDE from the Tuesday symposium on gases in metals, the Iron and Steel Division swung into action for the first time on the third day of the meeting with a discussion of iron and steel alloys. Dr. E. S. Davenport opened the discussion on Wednesday morning by presenting the paper written by himself in association with E. C. Bain and W. S. N. wiring on the equilibrium diagram of iron-manganese-carbon alloys. A written discussion by Mr. Scott showed qualitative agree- ment, but some quantitative disagreement. Messrs. Marsh and Sisco discussed the paper at length, pointing out non- agreement of certain conclusions with the phase rule. Dr. Krivobok, although differing with the authors on some points, stated that in his opinion the information collected would be valuable in the practical use of these alloys.

Jan 1, 1932

By Sherwin F. Kelly

NEW trend in geophysics has been uncovered in these depression years, made evident through the thinning cloak of commercial activity, which, in better times, would have completely obscured it. I refer to the increasing use of these methods for geological investigations by federal and state geological surveys. This is a trend that has been gathering momentum not alone in the United States, but abroad as well. Thus, in Poland, the Geological Survey has been playing an increasing role in geophysical work since 1927, and now has- its own geophysical department. The government petroleum producing organization of Argentina has its Geophysical Commission; Brasil boasts a completely equipped geophysical department in its Mineral Production Service; the government of Chile has contracted with commercial companies for geophysical surveys; Peru is planning an intensive program of geophysical prospecting in its petroliferous regions; and Canada has, for several years, cooperated with

Jan 1, 1935

By S. F. Shaw

MINING conditions in Mexico during the current year have been most unfavorable, synchronizing with conditions in the United States, but the outlook for the near future is improving. The chief difficulties met with are because of the following conditions: severe drop in prices of metals; high smelting rates; high prices of supplies; inadequate means of transportation; low efficiency of labor. In comparison with pre-war prices for metals it cannot be said that prices are low, particularly for silver, which recently has gone to a level that would have been considered exceedingly good in 1912. But conditions have changed so greatly that only the most favorably situated properties can operate without loss.

Jan 1, 1921

By Scott Turner

AS IN OTHER lines of engineering, progress in mining was influenced during 1931 by the world-wide economic depression. Low-metal prices ? resulted in active efforts to reduce production costs of base-metal mines. Probably the chief factors in reducing costs were the greater efficiency of labor, due to better relations between management and workmen, to the scarcity of jobs, reduced wages in most base-metal mines, and to lower overhead expenses secured by drastic economies. The use of mechanical equipment continued to increase, due to more efficient designs and a better practical understanding of the applicability of such equipment to requirements. With one exception, there were no startling innovations in stoping methods, but there was notable progress in the better adaptation of mining methods. In the United States, no large new base-metal or silver mines came into production during the year. At a number of mines, output was curtailed, and operations were discontinued at several important producers. On the other hand world-wide interest in gold was stimulated, as evidenced by increased output from producing mines, the reopening of some old properties, and intensive prospecting for new deposits. Mining methods at several gold mines in the United States and Canada were modified or changed to obtain a higher extraction of ore or to meet the need for additional support of the mine workings at depth. Permanent record of improvements in mining practices has been made during the year by the Federal Government; the industry thus has available for its use more detailed information than ever before. This work was done through cooperation of the mining companies and their representatives with the United States Bureau of Mines, whereby many papers descriptive of practices and costs at individual mines have been published. The Bureau&apos;s program of describing methods and costs at the more important mines (those producing in excess of $100,000 annually) is nearly completed, but papers will be issued concerning such additional mines as may possess particular interest because of novel methods, exceptional conditions or operating results, and others to supplement reports already issued. In this way, an interesting record of the results of changing conditions, or innovations in methods, will be made available.

Jan 1, 1932

By Reynold Q. Shotts

Data are presented which show that fractions of varying densities-from the same coals are oxidized at different rates by nitric acid. From oxidation data, the approximate quantity of "bright" and "dull" components may be calculated. Definite relationships between oxidation rate and rank are shown for density fractions from at least two bituminous coals.

Jan 1, 1950

By Joseph W. Richards

ALTHOUGH bad grammar, the above query is probably, at the present moment, good sense. Why was the Institute started and why does it continue to exist? The small group of men who worked out the original idea felt keenly the necessity of mining engineers and metallurgists getting together in order to discuss their professional problems. That necessity still exists but it does not strike the present generation of engineers so keenly because they have always had the Institute: they do not know what it is to be without it. The Institute is a great graduate school of mining and metallurgy. All of its members who have something to say worth saying are the teachers; all the rest may be learners or critics. No university or technical school can match the experience and information which the authors of its papers possess, no institution of learning has a body of potential listeners so extensive and so vitally interested.

Jan 1, 1921

By Arthur L. Walker

DURING my trip around the world last year, covering a total of 45,000 miles, I saw many things of especial interest from an engineering viewpoint. Sailing from New York, I went through the Panama Canal, down along the west coast of South America, then over the Peruvian and Bolivian Uplands; thence to the celebrated copper mines of Chile; across the Andes, to Buenos Aires, then to Rio Janeiro; across the Atlantic to Lisbon, Portugal; through Spain to the Rio Tinto mines; across southern Europe to Italy; thence to Alexandria and Cairo; up the Nile to Assouan, to Palestine through the Suez Canal, Red Sea and across to Bombay; up to the country of the Moghul Emperors; then to Calcutta, from which point I shipped to Singapore, as having crossed the Equator twice, I wished to shake hands with it again; thence to Shanghai and Pekin; up to the Great Wall of China, back to Nanking and up the Yangtse to Hankow; then back and eastward across the Pacific Ocean. The climatic changes were sudden and severe; there was winter where, for me, it should have been summer and vice versa. The weather man was very kind, however, and until I was near the Aleutian Islands there were only three rainy days in a total of 220.

Jan 1, 1924

By Raymond F. Gray, Victor J. Hoffman, Richard J. Bagan, Harold L. McKinley

The first indication of tungsten in the Bishop area was the discovery of scheelite concentrations in a gold placer operation in the ( since named) Tungsten Hills in 1913. After early intermittent production, the deposits of the district were slowly discovered and developed. The Pine Creek mine, located in 1916 and under the direction of Union Carbide Corporation since 1935, became the principal producer in the district. By the end of 1965, the total production of the district had reached 3,450,932 units of WO3, 17,071,242 pounds of molybdenum, and 19,599,110 pounds of copper. The topography of the district is characterized by its extreme relief, ranging in elevation from 13,986 feet to about 4400 feet in the Mount Tom quadrangle. The present topography is the result of the uplift and erosion of the Sierra Nevada and the great subsidence of the Owens Valley with its related deposition and volcanism. The general structure of the pre-Tertiary rocks consists of a series of tightly-folded metasedimentary and metavolcanic rock remnants surrounded by exposed plutons ranging in composition from hornblende gabbro to alaskite. The metasedimentary rocks consist of low- to intermediate-grade metamorphic equivalents of fine-grained sediments deposited during the Paleozoic era in a miogeosynclinal environment. Later volcanics were deposited in a eugeosyncline. The ore bodies in the Bishop district consist of scheelite-bearing tactite formed by the pyrometasomatic replacement* of calcareous sediments along the contact with an acidic granitic intrusive. A number of the metasedimentary remnants have had tungsten deposited along their edges.

Jan 1, 1968

By AIME AIME

A CORPORATION would go into bankruptcy if its affairs were conducted as are those of the state of New York, according to the Committee on New York State Government Reorganization of the American Engineering Council of the Federated American Engineering Societies, in a report to the chairman, of the Joint Judiciary Committees of the Senate and Assembly. The report, just made public, was signed by the three members of the committee who were appointed by Herbert Hoover. They were H. de-B. Parsons, chair- man, Paul G. Brown and Lewis B. Stillwell. Although the American Engineering Council is a national organization, it decided to aid in governmental reorganization in New York State because of the magnitude of the task. The Council&apos;s committee in its report urged the passage of three state reorganization amendments for consolidation of departments, an executive budget system, and a four-year term for the higher state officials. In the words of the report :

Jan 1, 1921