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By Herluf P. Nielsen, Robert I. Jaffee

IN recent years much attention has been given to high-melting alloy systems, It has been of interest in this respect to investigate the alloys of platinum and tungsten, which were known from the literature to have very high melting points up to about 50 pct tungsten, but about which little had been published on the high-tungsten side of the system. Powder metallurgical methods were used throughout this investigation for the preparation of the alloys, utilizing electrical sintering techniques such as are used for tungsten and molybdenum. In the course of the work it was found desirable to determine fusion temperatures of the alloys, and it was possible from these and other data to draw a tentative constitutional diagram (solidus, mostly) applicable to the high-temperature part of the system. No attempt was made to determine solid solubility vs. temperature data, nor to investigate the lower temperature transformations in the solid state. Data on the microstructure, hardness, and a note on oxidation resistance of the sintered alloys were obtained. PAST WORK Müller1 determined liquidus temperatures of platinum-rich alloys to 50 pct tungsten, using a radiation method employing a photoelectric cell, and found that the melting points increased progressively from 1771°C for platinum to 2350°C for the 50 pct alloy. Microscopic evidence by Müller that complete solid solutions exist to 50 pct tungsten was not checked by Kremer2 who, according to Vines and Wise,3 found that "although the 8 pct tungsten alloy was a solid solution, the 26 pct tungsten alloy contained a eutectic or an intermediate phase." Hultgren and jaffee4 using X ray methods found continuous solid solutions to at least 33.6 pct tungsten (35 at. pct) after annealing in vacuum for 6 days at 1000°C. Vines and Wise3 report work communicated to them by E. C. Rhodes on wrought alloys to 7 pct tungsten, which showed that tungsten hardened platinum extremely rapidly, and was one of the most potent hardeners of the binary additions to platinum. Considerable quantities of 4 pct tungsten platinum wire have been produced for grids in radar tubes and for aircraft spark plugs. Some of the alloy for the latter application is made by sintering, the remainder by smelting and casting. MATERIALS The platinum powder used in this work was kindly supplied by the research and Development Laboratory of the Owens-Corning Fiberglas Corp., Newark, Ohio, It was prepared from scrap platinum. After dissolving in aqua regia and evaporating almost to dryness, the solution was worked up several times with concentrated HCI. the resultant platinic chloride was diluted considerably, and metallic zinc was added, which precipitated the platinum in a very finely divided form. After dissolving the

Jan 1, 1948

By R. I. Jaffee, H. P. Nielsen

In recent years much attention has been given to high melting alloy systems. It has been of interest in this respect to investigate the alloys of platinum and tungsten, which were known from the literature to have very high melting points up to about 50 pct tungsten, but about which little had been published on the high-tungsten side of the system. Powder metallurgical methods were used throughout this investigation for the preparation of the alloys, utilizing electrical sintering techniques such as are used for tungsten and molybdenum. In the course of the work it was found desirable to determine fusion temperatures of the alloys, and it was possible from these and other data to draw a tentative constitutional diagram (solidus, mostly) applicable to the high-temperature part of the system. No attempt was made to determine solid solubility vs. temperature data, nor to investigate the lower temperature transformations in the solid state. Data on the microstructure, hardness, and a note on oxidation resistance of the sintered alloys were obtained. Past Work Miillerl determined liquidus temperatures of platinum-rich alloys to 50 pct tungsten, using a radiation method employing a photoelectric cell, and found that the melting points increased progressively from I771 C for platinum to 2350°C for the 50 pct alloy. Microscopic evidence by Miiller that complete solid solutions exist to 50 pct tungsten was not checked by Kremer2 who, according to Vines and Wise,3 found that "although the 8 pct tungsten alloy was a solid solution, the 26 pct tungsten alloy contained a eutectic or an intermediate phase." Hultgren and Jaffee4 using X ray methods found continuous solid solutions to at least 33.6 pct tungsten (35 at. pct) after annealing in vacuum for 6 days at I000 C. Vines and WiseS report work communicated to them by E. C. Rhodes on wrought alloys to 7 pct tungsten, which showed that tungsten hardened platinum extremely rapidly, and was one of the most potent hardeners of the binary additions to platinum. Considerable quantities of 4 pct tungsten platinum wire have been produced for grids in radar tubes and for aircraft spark plugs. Some of the alloy for the latter application is made by sintering, the remainder by smelting and casting. Materials The platinum powder used in this work was kindly supplied by the Research and Development Laboratory of the Owens-Corning Fiberglas Corp., Newark, Ohio. It was prepared from scrap platinum. After dissolving in aqua regia and evaporating almost to dryness, the solution was worked up several times with concentrated HC1. The resultant platinic chloride was diluted considerably, and metallic zinc was added, which precipitated the platinum in a very finely divided form. After dissolving the

Jan 1, 1949

By AIME AIME

FOUR separate groups of conveyors are installed in the Morenci Reduction Works as follows: (1) Ore-handling conveyors from the primary crushing plant to the coarse ore bin, from the coarse-ore bin to the secondary crushing plant, and from the secondary crushing plant to the ore bin in the concentrator plant. (2) Conveyors in the mill section of the concentrator plant. (3) Conveyors handling concentrate from the filter plant to the bedding plant, and from this plant to the smelter. (4) Conveyors handling flux and custom ore in the smelter crushing plant and to the bin at the bedding plant.

Jan 1, 1942

By Baxter C. Madden

Stress corrosion is defined and certain examples are illustrated. A number of test methods, to determine the resistance of materials to stress corrosion, are being developed at Wright Field. The criterion as to the validity of a method is stated. Three types of specimens and the method of stressing each type are described. Five different corrosive conditions are set forth. The results of tests to date, although too few for any general conclusions to be arrived at, are presented. The program for the continuation of the investigation is indicated. A bibliography is included. The development of the method of loading a cantilever-type specimen, so that a nearly constant stress at a large deflection may be realized, is presented as Appendix I.

Jan 1, 1945

CONTENTS PAGE GEISMER, H. S.-Coal Washing Practice in Alabama. Discussed by William Kelly, H. S. Geismer, H. D. Pallister, L. E. Bryant, Milton H. Fies, Elmer F. Harris, James A. Barr, George G. Crawford, E. C. Wright, George S. Rice, R. V. Norris 1 MILLER, F. W.-Byproduct Coking in Alabama. Discussed by Theodore Swann 4 FIES, MILTON H.-Alabama Coal Mining Practice. Discussed by Milton 11. Fies, R. V. Norris, R. D. Hall, L. E. Bryant, George S. Rice, H. S. Geismer 5 MUSSEY, H. E.-Blast-furnace Practice in Alabama. Discussed by C. A. Meissner, Franklin H. Crockard, H. E. Mussey, W. H. Oldham 14 Coal Washing Practice in Alabama Discussion of paper of H. S. GEISMER, presented at the Birmingham Meeting, October 1924, and issued, as Paper No. 1363-C, with MINING AND METALLURGY, September, 1924. WILLIAM KELLY, Iron Mountain, Mich.-Is the dry-cleaning method used? H. S. GEISMER.-Neither the dry-cleaning process nor the Chance sand-liquid method has been tested in Alabama; but all other methods used for cleaning bituminous coal have been largely brought to perfection in this state. H. D. PALLISTER, Tuscaloosa, Ala.-Have you the results from the recent work on the tables with reference to fine coal? H. S. GEISMER.-None of the iron-producing companies has adopted the tables, though three commercial operators have installed tables within the last six months. I tried to learn the results, but they were not willing to release the data just now. At the mines producing domestic coal, fines present a difficult problem; until within the past six months all the fine coal was wasted. The operators are trying to recover some of it on the table. L. E. BRYANT, Rockwood, Tenn.-Is there any connection between the sulfur content of the sludge and the effect of the sludge on vegetation?

Jan 7, 1925

By John A. Gann

The following investigation constitutes a brief réumé of the more important binary magnesium alloys from the standpoint of metallo-graphic technique, and the effect of heat treatment on structure and properties. The comparative newness of the subject justifies this procedure as a preface to a more detailed study of each individual series of alloys. The work was started with the idea of practical application in the industry rather than as a theoretical investigation. The alloy compositions studied were selected as those most likely to show whether heat treatment would produce beneficial results. Furthermore, it was considered satisfactory to use commercial 99.9 per cent. magnesium, the best commercial grade of alloying ingredients, and to limit the time of heat treatment at the expense of incomplete equilibrium. These facts must be kept in mind when examining the results obtained, and the conclusions drawn. Preparation of Alloys All melts were made in an oil-fired cast-steel pot, approximately 12 in. dia, by 12 in. deep. Approximately 15 lb. of flux and 50 lb. of magnesium were melted and the calculated amount of alloying metal was added. After thorough alloying and puddling, the metal was chill cast in a graphite mold with four 1/2 by 1/2 by 4 in. bars fed from a common sprue and runner. The next higher composition alloy in a given series was made by adding the calculated amount of metal to the heel from the preceding cast. The pot was thoroughly cleaned after each series and new flux then introduced, thus avoiding possible contamination from earlier melts. The percentage compositions given in Table 1 are the calculated values. While not all alloys were analyzed, enough were checked to indicate that the reported compositions are correct to a few tenths of one per cent. A more detailed description of the foundry methods employed has been given in a previous paper. 1

Jan 1, 1929

By John A. Gann

The following investigation constitutes a brief réumé of the more important binary magnesium alloys from the standpoint of metallo-graphic technique, and the effect of heat treatment on structure and properties. The comparative newness of the subject justifies this procedure as a preface to a more detailed study of each individual series of alloys. The work was started with the idea of practical application in the industry rather than as a theoretical investigation. The alloy compositions studied were selected as those most likely to show whether heat treatment would produce beneficial results. Furthermore, it was considered satisfactory to use commercial 99.9 per cent. magnesium, the best commercial grade of alloying ingredients, and to limit the time of heat treatment at the expense of incomplete equilibrium. These facts must be kept in mind when examining the results obtained, and the conclusions drawn. Preparation of Alloys All melts were made in an oil-fired cast-steel pot, approximately 12 in. dia, by 12 in. deep. Approximately 15 lb. of flux and 50 lb. of magnesium were melted and the calculated amount of alloying metal was added. After thorough alloying and puddling, the metal was chill cast in a graphite mold with four 1/2 by 1/2 by 4 in. bars fed from a common sprue and runner. The next higher composition alloy in a given series was made by adding the calculated amount of metal to the heel from the preceding cast. The pot was thoroughly cleaned after each series and new flux then introduced, thus avoiding possible contamination from earlier melts. The percentage compositions given in Table 1 are the calculated values. While not all alloys were analyzed, enough were checked to indicate that the reported compositions are correct to a few tenths of one per cent. A more detailed description of the foundry methods employed has been given in a previous paper. 1

Jan 1, 1929

By Fulton B. Flick

The micrography and macrography of aluminum and its alloys present certain difficulties. Many of the difficulties attendant on the micrography have been removed by methods developed during the past few years, notably those of E. H. Dix, Jr.1 The development of grain size in aluminum and its alloys may be equally troublesome, yet comparatively little detailed attention appears to have been given to it. Satisfactory reagents are available for the development of such structurcs in ferrous and most non-ferrous metals, but those applied to aluminum and its alloys, i. e., alcoholic or aqueous solutions of sodium hydroxide or hydrofluoric acid are not entirely satisfactory. Hanson and Arch-butt,2 in speaking of these two reagents, state that "These two reagents give fairly satisfactory results, but they sometimes produce badly tarnished surfaces from which the surface deposit is difficult to remove." It has been our experience that neither of these reagents is to be entirely relied on for developing structures suitable for study or photography. This means that when the etch fails to produce satisfactory results the specimen must be repolished, through the 000-paper at least, and then etched with another reagent. This procedure entails a considerable loss of time, and the final results may not be all that might be desired. However, the reagent to be described, although not a panacea for all etching troubles, has improved results so markedly that it is felt that it & worth offering as a grain-size etch generally applicable to aluminum and aluminum alloys. Czochralski3 in 1915 mentioned the application of a solution of 10 to 20 c. c. concentrated hydrofluoric acid in 100 c. c. absolute alcohol, etching in this reagent being followed by dipping in concentrated hydrochloric acid soliltion.

Jan 1, 1925

HAVING previously shown you how ores are found and mined, and also how they are prepared and disposed for smelting, and then how the blast furnaces and other furnaces are made for purging their earthiness, all this would be as nothing if I did not proceed to show you the method of smelting them. Therefore, in the present chapter I wish to show you how you must proceed in this very important operation, telling you all I have seen and also how much work with this kind of blast furnace I have done or directed. For this reason I tell you first to take by weight or measure the quantity of ore that you wish to smelt and, particularly if it is a kind that contains silver, break it into small pieces about the size of [52v] beans. If the ore had previously needed evaporation by fire or cleaning by washing, you will have had this done well and have had it properly prepared by a master sorter or others. A layer of this is arranged on a bed of planks, bricks, or flat stones in front of the blast furnace and its companion is placed on top, then a quarter part of galena or a third if you can obtain it. Then an equal part of crushed iron slag or slag from the same or different ore is added. These materials are spread in layers one above the other. When the blast furnace has been constructed as taught above, correct in all its parts, and is full of well-kindled burning charcoal, then fill it up with charcoal and admit water to the bellows machine. When you see that it is well kindled again from this wind and that the flames begin to come out forcefully on top, work it down with a little rake and fill it up again. Then the pannier is filled with new charcoal, the blast furnace heaped full, and another basketful of the said composition of ore is also put on top. Proceed in this way, continually adding charcoal and ore as long as you have any, or as long as you wish to keep up the work, maintaining the blast furnace always full, or continuing in this way until the bottom of the blast furnace is filled with melted materials. Decide this by judgment, or by seeing through the mouth of the tuyère where the wind of the bellows enters that they are level with this. Then with an iron tool open the hole that was left as an outlet in front of the blast furnace and allow all the metal with its slag to run out. These two things, flowing through the chan-

Jan 1, 1942

By R. I. Jaffee, H. R. Ogden, D. J. Maykuth

IN THE past year, Jaffee and Campbell&apos; and Finlay and Snyder2 reported on the mechanical properties of titanium-base alloys, some of which were in the same ranges of composition as are covered in this paper. In this paper, evidence confirming that given by Finlay and Snyder on the effects of carbon, oxygen, and nitrogen on titanium will be presented; and, in addition, new data will be given on the effects of these elements on the flow properties and phase transformation of titanium. Materials and Preparation of Alloys The preparation and general properties of iodide titanium have been adequately described elsewhere.&apos; , As-deposited iodide titanium rod, prepared at Battelle, of Vickers hardness less than 90 was employed as the base metal in the present work. This was the same material as that used by Finlay and Snyder.2 The probable analysis reported by them for standard quality metal holds here also: N 0.005 pct, 0 0.01 pct, C 0.03 pct, Fe <0.04 pct, A1 <0.05 pct, Si <0.03 pct, and Ti 99.85 pct. Carbon was added in the form of flake graphite supplied by the Joseph Dixon Crucible Co. Oxygen was added in the form of c.p. grade TiO, powder, produced by J. T. Baker Chemical Co. Nitrogen was added in Ti3N4 powder, supplied by the Remington Arms Co. Individual ingots weighed 7 or 8 g. Carbon, oxygen, or nitrogen was added by placing the corresponding powder in a capsule made from as-deposited iodide titanium rods and melting the capsule with the balance of the charge. The charge was are-melted with a tungsten electrode on a water-cooled copper hearth under a partial vacuum of very pure argon (99.92 pct minimum). Melting was practically contamination free. Vick-ers hardness increases of less than 10 points were normal for unalloyed iodide titanium control melts. Nitrogen analyses of are-melted iodide titanium showed a nitrogen content of 0.005 pct, about the same as is present in the as-deposited rod. No tungsten pickup was found in a melt of iodide titanium analyzed for tungsten. Weight losses in melting nitrogen-free alloys were very small and varied consistently from nil to 0.015 g (0 to 0.2 pct). This permitted the use of nominal composition for these alloys. Chemical analyses made for carbon, which can be analyzed conveniently by combustion methods, justified this procedure. Where nitrogen was added, considerable splattering took place. Here it was necessary to analyze for nitrogen by the Kjeldahl method. The ingots were hot rolled at 850°C to about 0.045 in. thick. After hot rolling, the strips were descaled by mechanical grinding, and then given a cold reduction of 5 to 10 pct to insure a uniform thickness throughout the length of the specimen. The edge strips and the tensile strips were annealed in a vacuum of 1x10-4 mm Hg pressure for 3 1/2 hr at 850°C and furnace cooled. Methods of Investigation Hardness Measurements: At least five Vickers hardness measurements were taken using a 10-kg load on each sample in the following conditions: (1) top and bottom of each ingot, (2) top and bottom surface of as-rolled and annealed sheet, and (3) on cross-section of annealed sheet and all quenched specimens. Tensile Tests: Tensile tests were conducted on Baldwin-Southwark testing machines having load ranges of 600 or 2000 lb. Tests were made on 1-in. gauge-length specimens, 3 1/4-in. overall length, 1/2 in. wide, 0.040 in. thick, with a reduced section 1 1/4 in. long and 0.250 in. wide. Two SR-4, A-7 strain gauges, one mounted on each side of the specimen, were used to measure the strain over a limited range to determine the modulus of elasticity. After the modulus of elasticity readings had been taken, load vs. strain readings were taken, using only one strain gauge, at increments of 0.0001 in. until the yield points were passed and then at 0.001-in. increments to the limit of the strain-gauge indicator (0.02 in.). Strain readings above 0.02 in. per in. were taken every 0.01 in., using dividers to measure the strain between the 1-in. gauge marks until the maximum load had been reached. Crosshead speed, when using the SR-4 gauges, was 0.005 in. per min, and, when using dividers, 0.01 in. per min. Flow Curves: Flow curves were determined using the true stress-true strain data obtained during the tension test. The usefulness of this type of information has been dealt with very adequately elsewhere by L. R. Jackson,&apos; J. H. Hollomon,6 and many others. Flow curves of true stress vs. true strain could be converted to the more conventional cold-work curve of 0.2 pct offset yield strength vs. percentage of cold reduction by means of the transformation, 1/1 = 1/1-R, where R is the fraction reduction in cold working. Thus, the true strains corresponding to percentage reduction can be calculated, and the 0.2 pct offset yield strengths scaled off the — 6 curve by taking the true stresses corresponding to the values of 6 + 0.002 strain. Heat Treatment: For the transformation studies, the alloys were heat treated in a horizontal-tube furnace using a dried 99.92 pct argon atmosphere, and quenched into water. Essentially no contamination was found after several hours of heat treatment at temperatures up to 1050°C. Metallography: Specimens were prepared in the

Jan 1, 1951

By John D. Sullivan

ALUMINUM and magnesium plants in the United States underwent enormous wartime expansion which made many wonder if ghost plants would result when industry swung back to a peacetime basis. Production capacity of primary aluminum ingots was stepped up from 150,000 tons annually to about 1,150,000 tons; magnesium production increased from 2500 tons in 1936 to nearly 200,000 in 1943, with a production capacity of some 300,000 tons. Not only was primary metal production enlarged but also the capacity of prime fabrications such as castings, forgings, extrusions, and sheets was correspondingly increased. In mid-December it was estimated that production of primary aluminum ingots in the United States in 1946 will be about 410,000 tons while consumption will be about 500,000, close to half of the wartime consumption. The 1946 estimated consumption of secondary aluminum is 200,000 tons. The critical shortage of soda ash is hindering production of primary metal, and the outlook for an early relief of this shortage is dark.

Jan 1, 1947

By Charles T. Malcomson

In the United States, improvements in methods of combustion have made possible the use of the smaller sizes of anthracite. This coal is now being reclaimed from the culm banks accumulated by the miners in the more prodigal years. To-day the freshly mined "slush" is segrega,ted and stored against the time when, through briquetting or some other means, it may be utilized as a commercial fuel. For many years Europe has achieved enviable results in the conservation of her small coal by briquetting. This profitable industry, first placed on a commercial basis in France in 1842, has grown to such magnitude that the production during 1913 exceeded 36,000,000 short tons. Briquets produced in Great Britain are used principally for steam purposes and the greater part of the output is either exported or taken by the Admiralty. On the Continent the briquets are sold in all branches of the coal trade. The French railways consume from 16 to 40 per cent. of their fuel in briquet form, and in Germany the lignite briquets (of which 20,000,000 tons were produced in 1913) are as familiar and interesting to the American traveler as the huge porcelain stoves in which they are burned. It is not strange, therefore, that aggressive and far-sighted promoters heralded this means of converting our ubiquitous coal waste into revenue. To the superficial student the briquetting process seemed so simple as to make success easy. It is for this reason principally that the path of the industry in America has been strewn with failures. The rash enthusiast had either not worked out the mechanical problems involved or had failed to grasp the local conditions under which the briquets must be made and sold. It may be confidently stated, however, that in spite of the many vicissitudes through which it has passed, coal briquetting is now an accomplished economic success in this country, and as a profitable adjunct to the coal industry it has come to stay. Several valuable contributions relating to coal briquetting are found in the Transactions. Charles Dorrance, Jr., has sketched briefly the history of the anthracite briquetting plants from the time of Loiseau&apos;s pioneer plant down to that of the Lehigh Coal & Navigation Co. at Lans-ford. Since then this phase of the industry has remained practically at

Jan 1, 1915

The papers discussed in the following pages were presented during two sessions of the Geophysics Education Committee of the Mineral Industry Education Division on Feb. 17 and 18, 1941. At the first meeting, to consider the "Influence of Geophysics upon Geology Curricula," this Committee was joined by the Geophysics and Mining Geology Committees of the A.I.M.E., the Society of Economic Geologists, representatives of the American Geophysical Union, and delegates from the Committees on College Curricula and on Applications of Geology of the American Association of Petroleum Geologists. Quentin D. Singewald and Sherwin F. Kelly presided. At the ensuing session, especially emphasizing the integration of geology, physics and chemistry for the solution of earth problems, the joint participants with the Geophysics Education Committee were the Geophysics Committee, and representatives of the American Geophysical Union and of the Committee on College Curricula of the American Association of Petroleum Geologists. Richard M. Field and W. R. Chedsey presided. In the following summary of the discussion at the two meetings, written discussion submitted subsequently is not differentiated from that offered orally at the session. A provisional report of the Geophysics Education Committee was presented at the second session, and some of the following discussion refers to it. This report has not been printed (it is anticipated that a more comprehensive, final one will be rendered at the 1942 annual meeting). A few mimeographed copies of this provisional report were made. Dr. W. P. Haynes presented some notes prepared by Dr. F. H. Lahee, Chairman of the American Association of Petroleum Geologists&apos; Committee on College Curricula. This Com- mittee&apos;s inquiries reveal the general opinion that a four-year academic preparation is inadequate, five or six being advisable. The fundamentals, mathematics, physics, chemistry, and English composition, should be stressed in the first three years, with specialization in the last two or three years. Some companies provide an apprenticeship period, and themselves give additional training. During academic years more attention needs to be given to engineering training, to field mapping, and in geology to stratigraphy and sedimentation. The amount of mere memory work should be cut, and men trained to observe and reason. Dr. Lahee emphasized the need of more adequate preparation in English composition, because of the inability of many graduates to compose acceptable reports. Sherwin F. Kelly pointed out that much time in university training, which ought to be devoted to technical subjects, was taken .up with English courses. He emphasized that it is the part of the universities to demand of the high schools that the students they send to the university be properly trained to speak and write English. Prof. W. T. Thom protested against the crowding of high-school material into already overcrowded college curricula. C. E. Dobbin, chairman of the Committee on Applications of Geology of the American Association of Petroleum Geologists, described briefly the work of his committee in publicizing geology, and said that it found a widespread popular interest in the subject but a lack of appreciation of its importance. He recommended that attempts to coordinate the works of geologists and geophysicists be expanded somewhat toward the further developing and encouraging of a "species of geopolitician" capable of assisting the progress of geology and geophysics by more vigorous advertising of

Jan 1, 1946

The papers discussed in the following pages were presented during two sessions of the Geophysics Education Committee of the Mineral Industry Education Division on Feb. 17 and 18, 1941. At the first meeting, to consider the "Influence of Geophysics upon Geology Curricula," this Committee was joined by the Geophysics and Mining Geology Committees of the A.I.M.E., the Society of Economic Geologists, representatives of the American Geophysical Union, and delegates from the Committees on College Curricula and on Applications of Geology of the American Association of Petroleum Geologists. Quentin D. Singewald and Sherwin F. Kelly presided. At the ensuing session, especially emphasizing the integration of geology, physics and chemistry for the solution of earth problems, the joint participants with the Geophysics Education Committee were the Geophysics Committee, and representatives of the American Geophysical Union and of the Committee on College Curricula of the American Association of Petroleum Geologists. Richard M. Field and W. R. Chedsey presided. In the following summary of the discussion at the two meetings, written discussion submitted subsequently is not differentiated from that offered orally at the session. A provisional report of the Geophysics Education Committee was presented at the second session, and some of the following discussion refers to it. This report has not been printed (it is anticipated that a more comprehensive, final one will be rendered at the 1942 annual meeting). A few mimeographed copies of this provisional report were made. Dr. W. P. Haynes presented some notes prepared by Dr. F. H. Lahee, Chairman of the American Association of Petroleum Geologists&apos; Committee on College Curricula. This Com- mittee&apos;s inquiries reveal the general opinion that a four-year academic preparation is inadequate, five or six being advisable. The fundamentals, mathematics, physics, chemistry, and English composition, should be stressed in the first three years, with specialization in the last two or three years. Some companies provide an apprenticeship period, and themselves give additional training. During academic years more attention needs to be given to engineering training, to field mapping, and in geology to stratigraphy and sedimentation. The amount of mere memory work should be cut, and men trained to observe and reason. Dr. Lahee emphasized the need of more adequate preparation in English composition, because of the inability of many graduates to compose acceptable reports. Sherwin F. Kelly pointed out that much time in university training, which ought to be devoted to technical subjects, was taken .up with English courses. He emphasized that it is the part of the universities to demand of the high schools that the students they send to the university be properly trained to speak and write English. Prof. W. T. Thom protested against the crowding of high-school material into already overcrowded college curricula. C. E. Dobbin, chairman of the Committee on Applications of Geology of the American Association of Petroleum Geologists, described briefly the work of his committee in publicizing geology, and said that it found a widespread popular interest in the subject but a lack of appreciation of its importance. He recommended that attempts to coordinate the works of geologists and geophysicists be expanded somewhat toward the further developing and encouraging of a "species of geopolitician" capable of assisting the progress of geology and geophysics by more vigorous advertising of

Jan 1, 1946

By F. E. Bash

Constantan is an alloy of copper and nickel that is extensively used, under a number of trade names, as a resistance wire with a low temperature coefficient of resistance, and one of the elements of base-metal thermocouples, iron usually being the other thermoelement, although for low-temperature work copper is also used. Before the war, constantan was imported, in common with many other technical necessities. Since it required considerable time to receive the constantan after it was ordered, fairly large stocks were kept on hand; but after the beginning of the war no more was imported and the stocks of foreign material were exhausted about the same time that the steel and munition manufacturers began to need great quantities of it for thermocouples for the heat treatment of steel. To meet this demand, the International Nickel Co. began manufacturing constantan that met all the requirements of the users of resistance wire but did not give the same electromotive force against iron as the German material and consequently could not be used with instruments calibrated for a definite e.m.f.-temperature relation. It so happened that all the constantan made had an e.m.f. lower than that necessary to meet the specifications of the Leeds & Northrup Co. for whom this investigation was carried out. If some had been higher and some lower, good wire could have been obtained by a process of selection, but as it was no wire at all could be procured. To remedy this situation, a thorough investigation was started with the close cooperation of the International Nickel Co. and the Electrical Alloys Co. The specifications to which the constantan had to conform were that it should give an e.m.f. of 47.40 millivolts against pure iron at 1500" F. (816" C.) with the cold-junction temperature at 0" F., or a proportional e.m.f. at temperatures near 1500" F. The method of checking a wire was as follows: It was first welded to a piece of iron wire; Armco iron was found to be satisfactory but iron with greater than 0.1 per cent. carbon would give a lower e.m.f. against the same piece of constantan than pure iron. The couple was then insulated and the fire end was tied to the

Jan 1, 1921

By Gerhard Derge, J. Warren Stewart

Extrusion processes are used in the commercial production of a wide variety of products, as indicated by the review presented a few years ago by D. K. Crampton.&apos; Most writers have confined themselves to a general description of the equipment and products and the engineering aspects of the process. The few studies that have dealt with the metallurgical side of extrusion have been concerned primarily with an examination of the mode of flow of the metal during extrusion. This has been accomplished by the use of composite billets, by scribing grids on symmetrical sections of billets and observing the change of dimensions in the gridwork, or by examining microstructures in extruded sections.2"8 Ariotlier limitation of these original studies is that they were confined to the extrusion of very simple shapes, usually rods having a diameter of about one-fourth that of the billet. Tin is particularly well suited to the extrusion of collapsible tubes and similar shapes in which the extruded section is very small in comparison to the diameter of the billet or slug. In modern production, impact extrusion methods are generally employed, therefore the thickness of the slug is small compared to its diameter. Under these conditions the process differs considerably from the processes that have been most fully described in the literature, and it is known that the quality of the product is very sensitive to slight variations in any one of the many variable factors involved, such as coinposition and structure of the alloy, rate of extrusion, temperature, shape of punch and die. An exhaustive examination of all of the above-mentioned problems promises to produce so many data that it seems advisable to initiate the reports at this time, even though all of the factors outlined have not been examined fully, and to confine this paper to a description of the apparatus and method. Only tin and its alloys with small amounts of copper have been considered. These are the alloys most commonly used in this country for the production of the type of articles already described.

Jan 1, 1940

By Gerhard Derge, J. Warren Stewart

Extrusion processes are used in the commercial production of a wide variety of products, as indicated by the review presented a few years ago by D. K. Crampton.&apos; Most writers have confined themselves to a general description of the equipment and products and the engineering aspects of the process. The few studies that have dealt with the metallurgical side of extrusion have been concerned primarily with an examination of the mode of flow of the metal during extrusion. This has been accomplished by the use of composite billets, by scribing grids on symmetrical sections of billets and observing the change of dimensions in the gridwork, or by examining microstructures in extruded sections.2"8 Ariotlier limitation of these original studies is that they were confined to the extrusion of very simple shapes, usually rods having a diameter of about one-fourth that of the billet. Tin is particularly well suited to the extrusion of collapsible tubes and similar shapes in which the extruded section is very small in comparison to the diameter of the billet or slug. In modern production, impact extrusion methods are generally employed, therefore the thickness of the slug is small compared to its diameter. Under these conditions the process differs considerably from the processes that have been most fully described in the literature, and it is known that the quality of the product is very sensitive to slight variations in any one of the many variable factors involved, such as coinposition and structure of the alloy, rate of extrusion, temperature, shape of punch and die. An exhaustive examination of all of the above-mentioned problems promises to produce so many data that it seems advisable to initiate the reports at this time, even though all of the factors outlined have not been examined fully, and to confine this paper to a description of the apparatus and method. Only tin and its alloys with small amounts of copper have been considered. These are the alloys most commonly used in this country for the production of the type of articles already described.

Jan 1, 1940

By H. Rees

This paper supplements and brings up to date a report prepared earlier this year and presented at the Eleventh Pan American Railway Congress in Mexico City. Most of the original report is contained in this paper in order to acquaint the reader with the project background. On December 1, 1961, construction of this locomotive was completed. Stationary testing started immediately, and a host of problems in various areas were uncovered. Many of these had no relation to the use of coal in a direct fired gas turbine. All of them emphasized the problems which plagued previous projects of this kind. In 1944 the Locomotive Development Committee of Bituminous Coal Research, Inc., was formed to study the problems of combustion, coal handling, and fly ash removal which would have to be solved before coal could be used to fire a gas turbine. By 1947 this committee was composed of the chief executive officers of nine eastern railroads and five eastern coal companies. All of the members of this committee were vitally concerned in a coal fired gas turbine because coal cost only one-fourth as much per heat unit as fuel oil. A number of research projects were started to develop and test components on a small scale. This included work at John Hopkins University, Battelle Memorial Institute, Institute of Gas Technology at Chicago, Purdue University, and Southern Research Institute. By 1946 a pilot plant had been installed at the Dunkirk, New York plant of Alco Products Div. of American Locomotive Co. The U. S. Bureau of Mines made available to the Locomotive Development Committee (hereafter called LDC) a Houdry process gas turbine plant, originally destined for a Russian oil refinery. The full scale pilot plant was used to evaluate the results obtained from the small scale studies under actual gas turbine conditions. Operation of this plant disclosed a number of problems which had not been discovered in the small scale tests. By 1951 four 250 hr tests had been conducted with the Houdry gas turbine to test out a variety of equipment. The major problem concerned the removal of abrasive fly ash from the products of combustion so that wear on turbine blades would not be excessive. The first 250 hr test showed that the original fly ash separating equipment was inadequate. Large ash particles passing through the turbine blading were nicking the leading edges of the first row blades. At the conclusion of the second 250 hr test, erosion was so severe that the first row of stator and the first row of rotor blades were replaced. At the end of the third 250 hr test, it was necessary to replace the first three rows of stator blading. The fourth test was used to test out a new design fly ash separator developed by LDC and named the Dunlab tube. This device gave more encouraging results than any of the others tested. Early enthusiasm for overcoming major difficulties had resulted in placing an order in 1946 with Allis-Chalmers Mfg. Co. for a 3750 hp regenerative gas turbine. The gas turbine, together with associated combustion and ash removal equipment, coal handling equipment, generators and gear reduction unit was installed at Dunkirk by 1951. A 750 hr test was made in 1952 with the LDC-Allis Chalmers gas turbine power plant. At the end of this test it was necessary to replace the first four rows of both rotor and stator blading. Rows 5 and 6 did not require replacement. In 1953 the American Locomotive Co. joined with LDC and assumed an active role in equipment development and manufacture. During 1954 LDC-Alco operated the rebladed gas turbine 300 hr to determine if a new fly ash separator was adequate. Performance of the improved separator was considerably better, but trouble was experienced with clogged blowdown lines from the Dunlab tubes. When these lines clogged it permitted the passage of abrasive particles. In 1955 a total of 1421 hr was run. This included 243 hr of cycle operation on Union Pacific coal from the D. O. Clark mine at Superior, Wyoming. During the 243 hr a total of 370 tons of coal was consumed. The purpose of this test was to determine if U.P. coal was suitable for use in a coal fired turbine. It was the unofficial opinion that it was as good or better than the eastern coals that had been tested.

Jan 1, 1964

By J. F. Tavernelli, L. F. Coffin

The deformation and fracture characteristics of eight metals subjected to fully reversed cyclic strain ranging from 0.2 to 50 pct were investigated at room temperature. Strain-hardening characteristics unique to the interna1 structure of a particular metal were found. Complete removal of the strain-hardening effects resulting from prior deformation was brought about by subsequent cyclic strain. Further support for the validity of the inverse relationship between the plastic strain range and the square root of the number of cycles for failure is given. THE resistance of materials to cyclic plastic strain is of interest both from a fundamental and practical point of view. It is now a well-accepted fact that fatigue failure in metals is a consequence of the localized slip deformation which occurs within the individual crystals of metal.&apos;-&apos; Hence the failure process should be strongly dependent upon the magnitude of the gross cyclic plastic deformation of the metal under conditions where this is a measurable quantity. Therefore, an experimental investigation of metals in which the cyclic plastic strain is the independent variable should shed new light on some of the basic aspects of the problem. From the practical point of view, there are many uses for information relating to the cyclic strain resistance of metals. One is the case of thermal stress fatigue where fatigue failure can occur as a consequence of a com- paratively few cycles of thermally induced mechanical deformation. Another is the mechanical working of metals where large cyclic strains are employed. In recent years several publications have appeared relating to the cyclic-strain resistance of metals,8-11 dealing mostly with the fracture aspects where the temperature is cycled simultaneously with the mechanical strain. Some work has been reported on the cyclic-strain resistance of metals at constant temperature, again oriented more toward the fracture aspects of the problem than the deformation aspects. 12-16 The present research investigation was undertaken to obtain information regarding the deformation characteristics of several metals whose structure-property relationships were simple and straightforward under conditions of both cyclic and monotonic strain. It has been shown for example that under cyclic-strain conditions some materials will strain harden, while other materials, particularly cold-worked structures, strain soften and these effects required further clarification.8,17-19 It was also de-

Jan 1, 1960

By T. L. Joseph

Blast furnaces are most efficient thermally when the CO2 in the top gas is highest. Oxygen introduced in the air blast is converted to CO in the combustion zones. The extent to which CO, generated in front of the tuyeres, is converted later to CO2 depends upon the ratio of ore to coke in the charge and the degree to which CO2, formed by reduction of iron oxides with CO, reverts to CO by the secondary reaction C + CO2 = 2CO. About 300 to 400 lb. of carbon&apos; per ton of pig iron is normally involved in the solution-loss reaction or direct reduction of FeO with carbon, which produces the same over-all results; that is, lower CO2 in the top gas. Rich2 has recently reported a reduction in fuel consumption at slower rates of blowing on two furnaces in spite of higher heat losses per ton of iron. Lower fuel consumption at slow operating rates was due to more complete reduction of the ore that resulted in higher CO2 in the top gas and consequently more efficient use of carbon. Kinney3 has reported substantial savings in fuel as a result of crushing and sizing the ore charge. Improvements in practice brought about by sintering magnetite concentrates, flue dust and fine ores have been due to the establishment of conditions favoring more complete reduction of the ore in the upper part of the furnace. The extent to which oxides and fluctuations in composition in pig iron affect the quality of steel and finished product needs further study. There is evidence that more thorough preheating and reduction of the ore in the upper part of the furnace tend to give a better quality of iron. Bogatzkii4 found from laboratory work that the amount of oxygen entering electrolytic iron, melted under various slags, was directly proportional to the concentration of free FeO in the slag and inversely proportional to the basicity of the slag. Herty and Gaines5 concluded that the silicate content of open-hearth steel before deoxidation is related to the concentration of silica in the pig-iron charge, indicating that most of the persistent inclusions are silica from the iron. They also found that

Jan 1, 1936