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By F. Keeler, C. M. Craighead

Aluminum alloys containing magnesium and silicon are susceptible to strengthening and hardening by suitable heat-treatments, and they constitute a class of alloys of considerable commercial importance. Generally, they contain these two elements in the proportions required for the formation of the intermetallic compound Mg2Si, or an excess of silicon; no commercial wrought alloys are made with an appreciable excess of magnesium. The reason for not having excess magnesium is obvious from the results given in this paper, since it is shown that excess magnesium results in a proportional decrease in the solubility of Mg2Si. This is the eighteenthl of a series of papers from the Aluminum Research Laboratories dealing with the equilibrium relations in aluminum-alloy systems; most of the previous publications concerned binary aluminum-alloy systems; this is the fourth of a group pertaining to ternary aluminum-alloy systems. The work on this system was completed in 1930, but the results were not published because of the pressure of other work. Hanson and Gaylor2, in 1921, presented the results of an extensive investigation of the aluminum-magnesium-silicon system. Their results indicated that an excess of magnesium over the amount required to form the compound MgzSi caused a noticeable decrease in the solid solubility of MgzSi in aluminum. A more recent investigation3 in these laboratories showed that the solid solubility of MgzSi in aluminum was 1.85 per cent at 595' C. and decreased to 0.30 per cent at 300' C. The results of the latter investigation were used as the basis for the present work. The Present Investigation In the present investigation, a study was made of the effect of various amounts of excess magnesium upon the solid solubility of MgzSi in

Jan 1, 1936

By L. P. Teas

The year 1931 has been one of unusual interest in Gulf Coast petroleum development, not so much because of the number of new prospects discovered, for apparently none of any present distinction have been found, but because of the discovery of so many new oil fields and the proving of so many old prospects. During the year 10 new oil fields have been found on the Coast; five in Louisiana and five in Texas. Two suspected salt domes were proven by the drill. Production dropped from a daily average of 192,000 to 162,670 bbl., or an average of 58 bbl. for each producing well, and active operations from 189 to 119. During 1931 the Coast produced approximately 48,600,000 bbl., or 44 per cent less than in 1930, when 86,500,000 bbl. were produced. The daily return at the beginning of the year was $192,000 and at the end only $126,780, the price having dropped from $1 for A grade and a range of $0.75 to $1.22 for B grade to a price range of 70 to 86c, or an average of 78c $ per barrel at the end of 1931. The average Coastal well produced 17,400 bbl. of oil during 1931. During the year development in the old fields has continued active at Barber's Hill only, although some work is in progress at Humble, Pierce Junction, Refugio and Pettus. Clear Lake is active but the large ownerships will prevent the "boom" type of field. Production is being held fairly steady at Barber's Hill and Pierce Junction, but has declined rapidly during the year at Refugio, Humble, and to a lesser degree at Pettus. The 6000-ft. production at Barber's Hill has shown a decided drop during the year and has not measured up to expectations.

Jan 1, 1932

By G. V. Cullen, N. G. Siviour

It has previously been reported that metal loadings of up to 6.8 m. eq/g. of dry coal can be obtained by contacting brown coal or lignite with ammoniacal solutions of ammine forming metals. Application of equilibrium expressions to further experimental results indicates that the extraction is by ion exchange, that the exchange is divalent-univalent for Zn, Cd and Ni, but is mainly univalent-univalent for Cu, and that to obtain reasonably uniform values for the equilibrium constants correction formulae must be applied to compensate for multiple functionality of the coal and its pH dependence in ion exchange. The results are shown to be consistent with the hypothesis that metal ammine complex cations are exchanged for protons derived from carboxyl and/or phenolic hydroxyl groups in the coal.

Jan 1, 1981

By John R. Weeks, Dan McLachlan, John R. Lewis

DURING the operation of the iron blast furnace, aggregates of hard, infusible, yellow, cubic crystals frequently form in the interstices of the lining and on the hearth of the furnace. These were first examined by Wohler&apos; and were identified by him as a complex cyanonitride of titanium, having a formula Ti(CN)2 • 3Ti3N2, or more simply Ti10C2N8. However, recent investigators have suggested that this complex compound does not exist. Recent work by Hume-Rothery, Raynor, and Little2 on the carbide and nitride particles in titanium steels suggests that a complete series of solid solutions of the general type Ti<0+y>C0Ny exists between titanium carbide (Tic) and titanium nitride (TiN). Assuming this to be true, it seems likely that Wohler&apos;s cyanonitride of titanium is in reality a solid solution of 20 mol pct Tic in 80 mol pct TiN, .the nearly consistent carbide-to-nitride ratio probably resulting from temperature and pressure conditions in the blast furnace. The object of the present work was to investigate thoroughly this possibility of a solid solution by using the single-crystal methods of X-ray analysis. A spectrographic qualitative analysis of a sample of the yellow crystals furnished by the Geneva Steel Co. sh&apos;owed, in addition to the titanium, strong lines of vanadium and moderate to weak lines of iron, magnesium, silicon, aluminum, and calcium. The last five were probably slag impurities, but the vanadium was possibly included in the yellow crystals, owing to a great structural similarity of its carbide (VC) and its nitride (VN) to the titanium compounds, Table 11. A chemical analysis was made

Jan 1, 1952

By Thomas A. Simpson

THE Birmingham red iron ore district in Jefferson County, north central Alabama, Fig. 1, is bounded on the northwest by the Warrior and Plateau coal fields and on the southeast by the Cahaba and Coosa coal fields. The area of study includes the ridge and valley between Red Mountain and Shades Mountain, Fig. 2, approximately 70 square miles extending from Homewood in the northeast to Greenwood in the southwest. The district is one of the most important producers of hematite in the United States, with an annual production of about 7 million tons. The amount of hematite mined between 1870 and 1950 ranged from 6 to 16 pct of the nation&apos;s total annual production, and the iron and steel products from blast furnaces in the Birmingham district supply the entire southeastern section of the country.

Jan 1, 1955

By W. E. C. Coxe

Many of you who are interested in the manufacture of iron and steel, have no doubt heard of the "Wheeler process for combining iron and steel." Mr. Wheeler has formed a company, styled the "Combination Trust Company," whose business is to grant licenses for the use of this patent process in producing what he calls "iron-clad steel." It has been proposed to apply it in the manufacture of car or wagon axles, also to shafting, having steel cores or centres covered with iron; to tubes of steel with an inner and outer skin of iron ; to structural purposes, such as girders and beams; bridge and tie-bolts, where the strength of the iron and the rigidity of the steel would be desirable. In answer to a request from Mr. Wheeler, permission mas accorded him to make some experiments at the rolling mill of the Philadelphia and Reading Coal and Iron Company, at Reading, Pennsylvania, with a view to manufacturing some steel-headed rails. In making this kind of a rail two difficulties are encountered. If the iron is brought to the requisite heat to weld properly, the steel is likely to be burned; if the steel is cared for, to prevent burning, the several layers of iron are not brought up to the proper welding heat. Mr. Wheeler claimed that the steel slab covered with iron which he furnished for the head of the rail could net be injured by any heat to which it might be subjected in the ordinary course of heating the rail-pile. He claimed, also, that by this method the porosity, which he thought was characteristic of all solid rails of Bessemer steel, would be overcome. Four steel slabs were furnished for this experiment, being Bessemer steel of .61 carbon, made at the Edgar Thomson Steel Works, and covered with iron in one of the Pittsburgh mills. The slabs were in section seven inches wide by three inches thick, and the iron covering was one-eighth to three-sixteenths inch thick. Each slab was placed on a pile of iron made up in the ordinary way for a rail fifty-six pounds per yard and thirty feet long. The heating was under the personal direction of Mr. Wheeler, and

Jan 1, 1879

By R. V. Vines, E. M. Wise

It is known qualitatively that the recrystallization behavior of platinum is dependent upon the amount and particularly the nature of impurities present, the amount of prior cold-work and the annealing time and temperature, but published data are limited. A study of the effects of cold-work and annealing temperature on the hardness of a sample of very pure platinum was undertaken to supply part of this information. Conclusions 1. The platinum used in the experiments had a probable platinum content of 99.99+ per cent, and had the following mechanical properties in the completely softened condition: Vickers hardness number, 39.4; ultimate tensile strength, 19,340 lb. per sq. in.; proportioilal limit, very low; elongation, 37.5 per cent in 2 inclles. 2. The effect of cold-rolling on the hardness is shown in Fig. 1. The hardness increases rapidly up to 10 to 15 per cent reduction and more slowly up to about 75 per cent reduction, beyond which it increases more rapidly. 3. The recrystallization temperatures for a 15-min. anneal, after cold-rolling 19, 39.5, 50.8, 66, 80.5 and 89.5 per cent reduction in thickness, are approximately 765°, 700°, 635°, 600°, 545&apos; and 425°C., respectively. 4. The recrystallized grain size of this platinum is a function of the percentage of cold reduction, being larger the lower the percentage of cold-work. 5. Little or 110 grain grourtll resulted from subjecting recrystallized samples to higher temperatures or annealing for longer times. Prior Work As already mentioned, data on the recrystallization of platinum are scarce. Gmelin&apos;sl handbook, which summarizes data published earlier than August 1938, lists values ranging from 400&apos; to 810°C. for the minimum temperature of recrystallization of samples with rather indefinite

Jan 1, 1940

By E. M. Wise, R. V. Vines

It is known qualitatively that the recrystallization behavior of platinum is dependent upon the amount and particularly the nature of impurities present, the amount of prior cold-work and the annealing time and temperature, but published data are limited. A study of the effects of cold-work and annealing temperature on the hardness of a sample of very pure platinum was undertaken to supply part of this information. Conclusions 1. The platinum used in the experiments had a probable platinum content of 99.99+ per cent, and had the following mechanical properties in the completely softened condition: Vickers hardness number, 39.4; ultimate tensile strength, 19,340 lb. per sq. in.; proportioilal limit, very low; elongation, 37.5 per cent in 2 inclles. 2. The effect of cold-rolling on the hardness is shown in Fig. 1. The hardness increases rapidly up to 10 to 15 per cent reduction and more slowly up to about 75 per cent reduction, beyond which it increases more rapidly. 3. The recrystallization temperatures for a 15-min. anneal, after cold-rolling 19, 39.5, 50.8, 66, 80.5 and 89.5 per cent reduction in thickness, are approximately 765°, 700°, 635°, 600°, 545&apos; and 425°C., respectively. 4. The recrystallized grain size of this platinum is a function of the percentage of cold reduction, being larger the lower the percentage of cold-work. 5. Little or 110 grain grourtll resulted from subjecting recrystallized samples to higher temperatures or annealing for longer times. Prior Work As already mentioned, data on the recrystallization of platinum are scarce. Gmelin&apos;sl handbook, which summarizes data published earlier than August 1938, lists values ranging from 400&apos; to 810°C. for the minimum temperature of recrystallization of samples with rather indefinite

Jan 1, 1940

By Fred P. Dewey

In my paper on the porosity and specific gravity of coke, read at the Roanoke meeting, June, 1883, and published in this volnme, an analysis by Dr. henry Froehling is reported (p. 10 of the preliminary edition of the paper, or p. 120 of this volume), as showing the composition of Fire Creek coke. This analysis WaS of coke made in beehive ovens at Low Moor, Va., from New River coal. Dr. Froehlng&apos;s analysis of the Fire Creek coke was as follows: Moisture..........0.260 Volatile matter.........0.260 Fixed carbon .........92.377 Ash 1....6.750 Sulphur..........0.535 Phosphorus.........0.0146 Both analyses are reported side by side in The Erginias for 1883, p. 99. By an error in copying, the Low Moor analysis was trans-

Jan 1, 1884

By Thomas M. Plouf

Getting optimal performance from flotation cells can, in many cases, be critical to a project&apos;s economic viability. Simple testing procedures can sound early warning signals as well as maintain optimum recoveries from the flotation cycle. The materials required for a simple testing laboratory include: (1) pH meter or pH paper, (2) bottles of reagents used in plant flotation, (3) stop watch, (4) calibrated eye droppers. (5) laboratory flotation machine (1000-g tank, open impeller), (6) froth collection pans, (7) magnifying glass, (8) sizing screen sufficient to retain 10% of the flotation feed coarse fraction, (9) sizing screen for the size particles at which desliming of the plant flotation feed is to take place, and (10) a set of screens covering the complete range of feed particle size.

Jan 4, 1978

By J. E. Tobey

UNDER war conditions coal immediately assumes a position of highest importance for coal must carry the basic load for industry. The upward trend in production continued through 1941. Bituminous coal production alone about equaled the total output of bituminous and anthracite in 1940. The figures for 1941 approximated 500,000,000 tons for bituminous, and 54,000,000 tons for anthracite, and production of by-product and beehive coke exceeded that of the previous year. The coal industry, under the National Bituminous Coal Act, is going through a period of readjustment, and is beginning to stabilize itself under the statute. The Federal Mine Inspection Nill became law during the year.

Jan 1, 1942

By Winston A. Wong, John J. Jonas

Commercial purity aluminum was deformed by extrusion over the temperature range 320° to 616°C and the strain rate range 0.1 to 10 per sec. Flow stresses and strain rates were calculated from the experimenLa1 ram pressures and speeds. The stress-strain rate-lemperature relationship in extrusion was found to be similar to that in creep. Extrusion, torsion, compression, and creep data extending over ten orders of magnitude of strain rate and over two orders of magnitude of stress were correlated by a single creep equation. It was concluded that hot-working is a thermally activated process, in which the rate-controlling mechanism is either the climb of edge dislocations or [he motion of jogged screw dislocations. The microstructural changes observed during extrusion were consistent with the proposed deformation mechanisms. ALTHOUGH great progress has been made in understanding the technology of extrusion, very little is known about the actual deformation mechanisms operating during flow. Previous accounts describing extrusion have indicated that the relationship between ram speed (V), pressure (P), and temperature (T) can be given as follows:1 V = apb and P = A&apos; exp(-AT). In these equations, a and b are constants which depend on temperature, A&apos; is a constant which depends on ram speed, and A is a "coefficient" with a different value for each metal. Although these equations have fairly wide application, they do not contribute much to a fundamental understanding of the deformation. Furthermore, extrusion has not hitherto been considered as a thermally activated rate process. This lacuna is surprising because hot-working is similar to high-temperature creep in several respects. There is, in fact, a fair body of experimental evidence suggesting that the material response under hot-working conditions is similar to that occurring under creep conditions, in spite of the many orders of magnitude difference in strain rate.2"4 Since creep has been extensively analyzed in terms of dislocation mechanisms, the comparison of hot-working to creep is useful, for it can suggest the possible deformation mechanisms operating during hot-working. In this paper, the hot extrusion of aluminum will be examined from the point of view of thermally activated deformation mechanisms, such as operate during creep. EXPERIMENTAL PROCEDURE The experimental procedure consisted of extruding commercial purity aluminum* over a range of ram velocities and temperatures at constant die reduction by the direct method. Details of the experimental equipment have been published elsewhere.5 Extrusion was carried out at each of the following billet temperatures: 320°, 376°, 445°, 490°, 555°, and 616°C at the following constant ram speeds: 0.002, 0.008, 0.02, 0.1, and 0.2 in. per sec.* All results were obtained using a square-shouldered die with an extrusion ratio of 40:1, giving a reduction in area of 97.5 pct. The ram force was the dependent variable, and was measured by means of strain gages on the ram and was plotted as a function of ram travel. The sequence of events before making an extrusion was duplicated before each run so as to minimize as much as possible variations in experimental conditions. For example, after the equipment had been assembled, the billet was allowed to heat up to temperature inside the insulated container. Once the container attained the desired temperature, a period of 1/2 hr was allowed to elapse before the extrusion was made. This time was found to be required to allow the billet to reach a steady-state temperature, as determined from previous tests. When all was ready, extrusion was carried out without interruption; that is, the billet was upset and extruded in one operation. EXPERIMENTAL RESULTS AND DISCUSSION The two usual experimental approaches for investigating high-temperature deformation exhibit an important common feature. In the first approach, which corresponds to creep, a constant stress (or load) is applied to the material at constant temperature and the resultant strain is recorded against time. After an initial transient stage, a state of constant strain rate exists (secondary creep), in which a steady-state condition is established which is sensitive to variation in either applied stress or temperature. In the second approach, a constant strain rate is applied and the resultant flow stress is recorded. This corresponds to the situation in hot torsion or hot compression, where it is observed that, for a constant test temperature, there is an initial rise in stress to a steady value which is maintained up to very high strains. In tests of this type, a steady-state region is also established in which the stress is sensitive to variation in either the strain rate or the temperature.3,4,6-16 In both types of tests, therefore, a steady-state region is established after an initial transient. In the case of hot-working this region may be called steady-state hot-working, and it is analogous to steady-state creep with which it has many common features. Stress Dependence of the strain Rate in Extrusion. In order to assess the stress dependence of the strain rate under extrusion conditions, and to compare it to that of creep, as well as of hot torsion and hot compression, the extrusion data were analyzed according to power, exponential and hyperbolic sine creep equations.

Jan 1, 1969

By Ottar Dragge, C. Danielsson, Bo Kalling

DISCUSSION, T. L. Joseph presiding L. F. Reinartz (Armco Steel Corp., Middletown, Ohio) —I would like to know, in the practical application of the Kalling process, what kind of a lining was used, how thick was the lining, and how much metal was treated at one time? S. Fornander (author&apos;s reply)—The rotary furnace is lined with a course of fireclay bricks 6 in. thick. This course is backed by 5 in. of insulation. The furnace has a capacity of about 15 tons. Mr. Reinartz—How was the ladle preheated? Mr. Fornander—As pointed out in the paper, the furnace was heated by a gas flame in the beginning of the experiments. During these first tests, however, the desulphurization was inconsistent. We think that this was due to the fact that iron droplets sticking to the furnace walls were oxidized by the gas flame. Now, the furnace is operated without preheating of any kind, and the results are much better. T. L. Joseph (University of Minnesota, Minneapolis, Minn.)—I might add one comment. This furnace was heated with a flame and for a time they had a little difficulty due to some residual metal in the rotating drum that would oxidize in between treatments and they found therefore, that it was very essential to drain the drum completely of metal so that they would not build up any ferrous oxide between treatments and they eliminated some of their erratic heats by maintaining those more reducing conditions. It was interesting to watch this operation. As soon as the drum started to rotate there was considerable flame, at least, at the time I saw it, that came out around the flanges, indicating there was quite a little pressure on the inside of the drum. W. 0. Philbrook (Carnegie Institute of Technology, Pittsburgh)—Is the reaction slag in the Kalling process liquid or solid, and how is it separated from the metal? Mr. Fornander—In the process there is no slag in the usual sense of the word. The lime powder does not melt during the treatment. After the treatment the lime is still in the form of a fine powder. It is separated from the metal by means of a piece of wood of suitable size placed within the furnace before it is emptied. D. C. Hilty (Union Carbide & Carbon Research Laboratories, Niagara Falls, N. Y.)—Dr. Chipman has given us some of his ideas in connection with a specific effect of silicon and silica on sulphur elimination and how silicon might interfere with desulphuriz- ing in the blast furnace. I wonder if he would like to elaborate on the possibility of a similar effect of silicon in the Kalling process? J. Chipman (Massachusetts Institute of Technology, Cambridge, Mass.)—Silicon does not interfere with the Kalling process. Anything that has strong reducing action is good for desulphurization. In these tests where the temperature was low compared to blast furnace temperatures, the silicon that is in the metal is a better reducing agent than the carbon. At high temperatures, carbon is the better. It is not the silicon in the metal that interferes with desulphurization, it is the silica in the slag. Mr. Joseph—I might add that the metal that was tapped from the drum after desulphurization was really at quite a low temperature. It was not measured, but I think it was well under 1300 °C, probably 1200" or a little above that. That was one of the difficulties, and I think there is no question about the fact that the Kalling process—in that it affects desulphurization between powdered lime, solid and liquid iron— is a reaction definitely between the solid lime and the liquid iron. E. Spire (Canadian Liquid Air, Montreal, Canada) — This Kalling process seems very interesting to us and after all it is only a mixing action that is taking place between the iron and the slag. We have attempted to do the same thing in another way. We have placed at the bottom of the ladle a porous plug through which we injected an inert gas. It can be nitrogen or argon. This plug is placed at the bottom of the conventional ladle and gas injected through the plug. That has appeared in our patent. To define this new type of treatment, I use the word gasometallurgy. I do not know if you like it, but it is a way of defining methods of treating metal using gases. What we do is exactly what is done in the exchange process in another way. We have a porous plug at the bottom with a high lime slag on top of the metal. Using this method, we have very good agitation of metal and slag, and with a small flow of gas, we can achieve a very strong agitation. For instance, in the 500 lb ladle, we use only 5 liters of gas a minute. We have an agitation compared to very rapidly boiling water in a pail. Moreover, the agitation can be controlled to create any amount of mixing desired. In a few minutes, with this method, the sulphur dropped from 0.58 to 0.11. These results have been improved since, and we have obtained results like 0.08

Jan 1, 1952

Meeting of Apr. 23, 1915.-The Iron and Steel Committee was authorized in its discretion to defer the date of acceptance of papers for the Hadfield Research Prize to Nov. 1, 1916. The sum of $250 was appropriated as a guarantee fund to establish a Library Research Bureau in co-operation with the other Founder Societies. The sum of $50 was appropriated to the Puget Sound Section. The sum of $250 was appropriated to the San Francisco Section. The sum of $125 was appropriated to the St. Louis Section. The matter of memorializing the New York State Constitutional Convention was referred to the New York Section of the Institute with authority to act as a Section only. Upon recommendation of the Committee on Membership, 50 Mem¬bers, 1 Associate, and 6 Junior Members were elected.

Jan 6, 1915

By David R. Mitchell

IF you are the owner of a mine, or a mine executive, or just an ordinary miner, and have a son about to go to college, do you urge him to take up mining engineering or do you try to dissuade him from such a course? If you live in the East, or the Middle West and your interest has been in coal rather than metal mining, the chances are that your young hopeful will be urged to do almost anything else rather than follow in father&apos;s footsteps.

Jan 1, 1939

By Sven Fornander

L. F. Reinartz (Armco Steel Corp., Middletown, Ohio) —I would like to know, in the practical application of the Kalling process, what kind of a lining was used, how thick was the lining, and how much metal was treated at one time? S. Fornander (author&apos;s reply)—The rotary furnace is lined with a course of fireclay bricks 6 in. thick. This course is backed by 5 in. of insulation. The furnace has a capacity of about 15 tons. Mr. Reinartz—How was the ladle preheated? Mr. Fornander—As pointed out in the paper, the furnace was heated by a gas flame in the beginning of the experiments. During these first tests, however, the desulphurization was inconsistent. We think that this was due to the fact that iron droplets sticking to the furnace walls were oxidized by the gas flame. Now, the furnace is operated without preheating of any kind, and the results are much better. T. L. Joseph (University of Minnesota, Minneapolis, Minn.)—I might add one comment. This furnace was heated with a flame and for a time they had a little difficulty due to some residual metal in the rotating drum that would oxidize in between treatments and they found therefore, that it was very essential to drain the drum completely of metal so that they would not build up any ferrous oxide between treatments and they eliminated some of their erratic heats by maintaining those more reducing conditions. It was interesting to watch this operation. As soon as the drum started to rotate there was considerable flame, at least, at the time I saw it, that came out around the flanges, indicating there was quite a little pressure on the inside of the drum. W. 0. Philbrook (Carnegie Institute of Technology, Pittsburgh)—Is the reaction slag in the Kalling process liquid or solid, and how is it separated from the metal? Mr. Fornander—In the process there is no slag in the usual sense of the word. The lime powder does not melt during the treatment. After the treatment the lime is still in the form of a fine powder. It is separated from the metal by means of a piece of wood of suitable size placed within the furnace before it is emptied. D. C. Hilty (Union Carbide & Carbon Research Laboratories, Niagara Falls, N. Y.)—Dr. Chipman has given us some of his ideas in connection with a specific effect of silicon and silica on sulphur elimination and how silicon might interfere with desulphuriz- ing in the blast furnace. I wonder if he would like to elaborate on the possibility of a similar effect of silicon in the Kalling process? J. Chipman (Massachusetts Institute of Technology, Cambridge, Mass.)—Silicon does not interfere with the Kalling process. Anything that has strong reducing action is good for desulphurization. In these tests where the temperature was low compared to blast furnace temperatures, the silicon that is in the metal is a better reducing agent than the carbon. At high temperatures, carbon is the better. It is not the silicon in the metal that interferes with desulphurization, it is the silica in the slag. Mr. Joseph—I might add that the metal that was tapped from the drum after desulphurization was really at quite a low temperature. It was not measured, but I think it was well under 1300 °C, probably 1200" or a little above that. That was one of the difficulties, and I think there is no question about the fact that the Kalling process—in that it affects desulphurization between powdered lime, solid and liquid iron— is a reaction definitely between the solid lime and the liquid iron. E. Spire (Canadian Liquid Air, Montreal, Canada) — This Kalling process seems very interesting to us and after all it is only a mixing action that is taking place between the iron and the slag. We have attempted to do the same thing in another way. We have placed at the bottom of the ladle a porous plug through which we injected an inert gas. It can be nitrogen or argon. This plug is placed at the bottom of the conventional ladle and gas injected through the plug. That has appeared in our patent. To define this new type of treatment, I use the word gasometallurgy. I do not know if you like it, but it is a way of defining methods of treating metal using gases. What we do is exactly what is done in the exchange process in another way. We have a porous plug at the bottom with a high lime slag on top of the metal. Using this method, we have very good agitation of metal and slag, and with a small flow of gas, we can achieve a very strong agitation. For instance, in the 500 lb ladle, we use only 5 liters of gas a minute. We have an agitation compared to very rapidly boiling water in a pail. Moreover, the agitation can be controlled to create any amount of mixing desired. In a few minutes, with this method, the sulphur dropped from 0.58 to 0.11. These results have been improved since, and we have obtained results like 0.08

Jan 1, 1952

By E. P. Pfleider, E. G. Malmlow, F. Landau

Friction drive hoists, long popular on the Continent, are now being installed in the U. S. and Canada by the Swedish firm of ASEA. Invented by C. F. Koepe and used first in 18.77, the principle is the same as that in elevator installations throughout the world. Inherent advantages of this system of hoisting were not fully developed until the recent introduction of the multiple-rope principle and design of concrete tower installations. Operators have a choice of independent operation of single skips and cages using counterweights, or use of skips or cages in balance. Also, hoisting control may be automatic, push button, or manual.

Jan 1, 1955

By Albert Sauveur

To understand this paper properly, the reader must have a clear conception of what is meant by the " critical points " of iron and steel; * and in order to avoid the necessity of tedious references to previous publications on the part of those unfamiliar with the subject, it is here briefly recapitulated. Critictl Points.—If a piece of steel containing, say, 0.50 per cent. or more of carbon, be heated to a high temperature and then allowed to cool slowly, the cooling proceeds at first at a uniformly retarded rate until a temperature of about 700° C. is reached, when there is a sudden " retardation " in the fall of

Jan 1, 1897

NEW MEMBERS The following list comprises the names of those persons who became members during the period Jan. 10 to Feb. 10, 1915: Members AGASSIZ, RUDOLPH Louis, Vice-Pres.,Calumet & Hecla Mining Co., Boston, Mass. AMIDON, RICHARD G., Min. Engr 3659 Girard Ave. N., Minneapolis, Minn. ANDERSON, HECTOR G. S., Min. Engr 323 N. 13th St., Muskogee, Okla. ANDERSON, JOHN CARTER, Petroleum Engr 2307 S. 33d St., Omaha, Neb. CLARKE, ALEXANDER FIELDER, Works Mgr., Firth-Sterling Steel Co., McKeesport, Pa. CROSS, CARLOS GARCIA, Min. Engr Calle Valparaiso 194, Vina del Mar, Chile. DAWSON, THOMAS WILLIAM, Min. Engr., Asst. Chief Engr., H. C. Frick Coke Co., Scottdale, Pa.

Jan 3, 1915

E. T. Turkdogan (British Iron & Steel Research Assoc., London, England)—I would like to suggest a different method for the treatment of the authors&apos; data on the Si-0 equilibrium in liquid iron. Because the activity coefficient of silicon dissolved in iron is influenced by the concentration of silicon as well as that of oxygen, the equilibrium constant K2 of reaction 2 becomes a function of metal composition, and, as shown in Fig. 1, a plot of log KP1 at 1600°C against the weight percent of silicon gives a smooth curve. A similar curve is obtained when log Kzl is plotted against the oxygen content of iron. Before

Jan 1, 1955