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By V. H. Wilhelm

The year 1941 in the California oil industry was marked by an increased market demand, drilling activity, and production of crude oil. Although seven new oil fields and two gas fields were discovered during the year, additions to reserves from these discoveries, as well as extensions and revaluations of previous discoveries, were approximately 100 million barrels, as against estimated withdrawals of 230,233,000 barrels. The year was remarkable for the very great increase in domestic demand for all products, which more than compensated for the loss in shipments to Japan, which averaged 60,041 bbl. Per day during 1940. Demand in terms of crude during 1941 was 648,967 bbl. per day as against 632,647 for the same period in 1940. This abnormal increase in demand is due to increased industrial activity, and especially increased railroad activity. Gasoline consumption for 1941 was 241,011 bbl. per day as against 217,744 in 1940. Demand for fuel oil increased from 259,806 bbl. per day in 1940 to 285,896 in 1941, and caused a withdrawal from stocks of more than 7,473,000 barrels. During 1941, total oil storage declined 9,153,000 bbl., but additions to storage of 1,754,000 bbl. of light oil and light oil products were offset by a withdrawal of 10,907,000 bbl. of heavier products. Production during the year is estimated at 230,233,000 bbl. as against 222,784,386 bbl. for 1940. TraNsportation For a short time, California was affected by lack of transportation due to the diversion of tankers. This shortage affected the movement of oil from the Sari Joaquin mated to the refineries, since a large percentage of this production is moved to the coast through pipe lines, and thence by tankers to Los Angeles and San Fran-,iSco, Return of the tanker fleet, which may be temporary, indicates that there is a possibility of ample supplies of petroleum products in the Pacific Northwest. Drilling Activity Contrary to general opinion, drilling activity increased in 1941 over the pre-vious Year, 942 wells being completed in 1941 as against 890 in 1940, an increase Of 6 per cent. This increase was due to the increased demands for fuel oil, and also to the decreased drilling costs, which made many former marginal locations economic. The main activity caused by increased demands for fuel oil was in the Mt. Poso, McKittrick, Midway and Santa Maria Valley oil fields. Dry-hole footage in 1941 was 655,354 ft. as against 583,537 ft. for 1940. Curtailment Voluntary curtailment succeeded in holding production considerably below demand, although it was above the state quota. During the year the top allotment

Jan 1, 1942

By V. H. Wilhelm

The year 1941 in the California oil industry was marked by an increased market demand, drilling activity, and production of crude oil. Although seven new oil fields and two gas fields were discovered during the year, additions to reserves from these discoveries, as well as extensions and revaluations of previous discoveries, were approximately 100 million barrels, as against estimated withdrawals of 230,233,000 barrels. The year was remarkable for the very great increase in domestic demand for all products, which more than compensated for the loss in shipments to Japan, which averaged 60,041 bbl. Per day during 1940. Demand in terms of crude during 1941 was 648,967 bbl. per day as against 632,647 for the same period in 1940. This abnormal increase in demand is due to increased industrial activity, and especially increased railroad activity. Gasoline consumption for 1941 was 241,011 bbl. per day as against 217,744 in 1940. Demand for fuel oil increased from 259,806 bbl. per day in 1940 to 285,896 in 1941, and caused a withdrawal from stocks of more than 7,473,000 barrels. During 1941, total oil storage declined 9,153,000 bbl., but additions to storage of 1,754,000 bbl. of light oil and light oil products were offset by a withdrawal of 10,907,000 bbl. of heavier products. Production during the year is estimated at 230,233,000 bbl. as against 222,784,386 bbl. for 1940. TraNsportation For a short time, California was affected by lack of transportation due to the diversion of tankers. This shortage affected the movement of oil from the Sari Joaquin mated to the refineries, since a large percentage of this production is moved to the coast through pipe lines, and thence by tankers to Los Angeles and San Fran-,iSco, Return of the tanker fleet, which may be temporary, indicates that there is a possibility of ample supplies of petroleum products in the Pacific Northwest. Drilling Activity Contrary to general opinion, drilling activity increased in 1941 over the pre-vious Year, 942 wells being completed in 1941 as against 890 in 1940, an increase Of 6 per cent. This increase was due to the increased demands for fuel oil, and also to the decreased drilling costs, which made many former marginal locations economic. The main activity caused by increased demands for fuel oil was in the Mt. Poso, McKittrick, Midway and Santa Maria Valley oil fields. Dry-hole footage in 1941 was 655,354 ft. as against 583,537 ft. for 1940. Curtailment Voluntary curtailment succeeded in holding production considerably below demand, although it was above the state quota. During the year the top allotment

Jan 1, 1942

By Howard Evans

Moderate but substantive gains were recorded in 1972 in the minerals processing industry. In the area of mill design, a number of large plants under construction during the past two to three years were tuned up and went into production. The application of operating controls has also made some significant strides. Progress here has been made in the areas of on-stream particle size analysis, on-stream x-ray analysis, slurry transportation, tripper control, flotation reagent control and digital control of grinding circuits. The major contributions to improved equipment are coming from smaller specialized equipment makers.

Jan 2, 1973

By Perry G. Harrison

The increased use of sintering for the beneficiation of iron ores and the reclaiming of flue dust creates a lively interest in sintering costs and economics. The character of material sintered and geographical location of plants so radically alter sintering costs and economics that it is well.to understand at least the basic elements which control such changes. The following cost factors are believed to be roughly approximated for large-scale Dwight-Lloyd continuously operated sinter-machine installations located anywhere. Per Crude Ton Labor, supplies and repairs 0.15 Power 6.5¢ X kw-hr. rate ? Plant overhead and administration 0.05 Depreciation per ton annual capacity 0.05 Fuel: 6 per cent coke breeze or equivalent minimum ? 1 per cent coke breeze additional for each 5 per cent free and combined water in ore or dust ? Ignition distillate at 0.6 gal. per ton ? Per Sinter Ton Royalty on ore 0.10 Royalty on flue dust 0.15 Per Crude Ton "Winter expense"; i. e., the cost of the five months enforced idle . period for plants tied in to Great Lakes transportation season 0.03 Using the foregoing data, it is possible to roughly approximate the cost of efficient sintering at any location for any ore, viz: Per Crude Ton Per Ton Handled Sinter 1. Flue Dust—Steel Plant Locations Sinter recovery, 15 per cent moisture and carbon 85 per cent Labor, supplies and repairs 0.15 0.18 Power 6.5¢ X 1¢ kw-hr. 0.065 0.08 Plant overhead and administration 0.05 0.06 Depreciation per ton 0.05 0.06 Dust handling and preparation 0.10 0.12 Fuel: free, contained in dust Ignition: blast-furnace gas free Royalty 0.15 Total $0.65 Note:—Cost increased by either deficiency or considerable excess of carbon in dust.

Jan 1, 1932

By R. I. Jaffee, J. G. Dunleavy, H. R. Ogden, Webster Hodge

INTRODUCTION EARLY in 1946, at the instigation of the U. S. Army Signal Corps, the authors made an extensive survey of the available literature covering high-strength, high-conductivity alloys. For the purposes of the Signal Corps, the minimum tensile strength to be considered was 150,000 psi, together with at least 50 pct IACS conductivity. No single alloy was found to be in production, or mentioned in the literature, which had this combination of properties. The constitution diagram for the iron-copper alloys is not well established in the respect to the two-liquid region. Fig I, taken from the 1939 Ed. of the ASM Metals Handbook, shows a two-liquid system existing above the liquidus temperature, but disconnected from it. Although Ruer and Fick1 and Ruer and Goerens2 definitely established the fact that two liquid layers could occur in the system, Ruer3 was not convinced that the line off immiscibility was closed in the center. Maddocks and Claussen4 found no liquid immiscibility at temperatures up to 1570°C in alloys containing almost no carbon. Although the diagram would indicate age hardening of the copper-iron alloys is possible, Hanson and Fords found that little hardening effect could be obtained. However, Gordon and Cohen6 reported that the response is better if the quenching is very efficient. Although iron has a potent effect on the conductivity of copper, Hanson and Ford5 have shown that, when hot-rolled copper iron alloys are aged at 1200°F, the electrical conductivity decreases sharply with iron contents up to 0.2 pct Fe, and then levels off at conductivities between 60 to 70 pct IACS with compositions to 2.1 pct Fe. They also found that aging did not increase the tensile strength, although increasing iron content gave a moderate improvement in strength. High-strength copper-iron alloys, usually containing about 60 pct iron, had been reported by Smith and Palmer.7 They found that an alloy containing 56.4 pct copper, 0.21 pct magnesium, balance iron, would give a maximum tensile strength of 170,000 psi and an electrical conductivity of slightly over 35 pct IACS. The alloy could also be processed to have 150,000 psi tensile strength, and about 41 pct IACS conductivity. Decreasing the iron content increased the electrical conductivity, but the long mushy range during freezing of the alloy containing 10 to 20 pct iron made the production of good castings difficult, In spite of the difficulty encountered by Smith and Palmer with alloys of around 20 pct iron, it was decided to make a rather complete investigation 0f this type of alloy. As a result 0f this investigation, a method of alloying and fabricating copper alloys containing 10 to 15 pct iron was developed

Jan 1, 1948

By R. I. Jaffee, J. G. Dunleavy, W. Hodge, H. R. Ogden

Early in 1946, at the instigation of the U. S. Army Signal Corps, the authors made an extensive survey of the available literature covering high-strength, high-conductivity alloys. For the purposes of the Signal Corps, the minimum tensile strength to be considered was 150,000 psi, together with at least 50 pct IACS conductivity. No single alloy was found to be in production, or mentioned in the literature, which had this combination of properties. The constitution diagram for the iron-copper alloys is not well established in the respect to the two-liquid region. Fig I, taken from the 1939 Ed. of the ASM Metals Handbook, shows a two-liquid system existing above the liquidus temperature, but disconnected from it. Although Ruer and Fickl and Ruer and Goerensz definitely established the fact that two liquid layers could occur in the system, Ruer3 was not convinced that the line of immiscibility was closed in the center. Maddocks and Claussen4 found no liquid immiscibility at temperatures up to 157oOC in alloys containing almost no carbon. Although the diagram would indicate age hardening of the copper-iron alloys is possible, Hanson and Fords found that little hardening effect could be obtained. However, Gordon and Cohen6 reported that the response is better if the quenching is very efficient. Although iron has a potent effect on the conductivity of copper, Hanson and Fords have shown that, when hot-rolled copper-iron alloys are aged at 1200°F, the electrical conductivity decreases sharply with iron contents up to 0.2 pct Fe, and then levels off at conductivities between 60 to 70 pct IACS with compositions to 2.1 pct Fe. They also found that aging did not increase the tensile strength, although increasing iron content gave a moderate improvement in strength. High-strength copper-iron alloys, usually containing about 60 pct iron, had been reported by Smith and Palmer.7 They found that an alloy containing 56.4 pct copper, 0.21 pct magnesium, balance iron, would give a maximum tensile strength of 170,000 psi and an electrical conductivity of slightly over 35 pct IACS. The alloy could also be processed to have I50,000 psi tensile strength, and about 41 pct I.\CS conductivity. Decreasing the iron content increased the electrical conductivity, but the long mushy range during freezing of the alloy containing 10 to 20 pct iron made the production of good castings difficult. In spite of the difficulty encountered by Smith and Palmer with alloys of around 20 pct iron, it was decided to make a rather complete investigation of this type of alloy. As a result of this investigation, a method of alloying and fabricating copper alloys containing 10 to 15 pct iron was developed

Jan 1, 1949

By W. O. Philbrook, K. M. Goldman, G. Derge

T. Rosenqvist—The most interesting point in this paper is the observed transfer of iron into the slag in the initial stage of the desulphurization process, after which the iron again is reduced to the metallic state. The authors interpret this observation as showing that the sulphur enters the slag as an iron-sulphur compound which subsequently is decomposed by the slag. The present writer has previously suggested the following equation for the desulphurization process: S + O2- ? S2- + O For equilibrium in the blast furnace the oxygen potential is defined by equilibrium with graphite and CO of 1 atm pressure: C + O ? CO [2] During the desulphurization process the reactions proceed in the direction of the arrows. If one assumes eq 2 to be significantly slower than eq 1, the transfer of sulphur into the slag, in accordance with eq 1, will build up a local oxygen potential at the metal-slag interface very much higher than that corresponding to the value defined by eq 2. This is possible because the equilibrium oxygen potential in eq 1 is high as long as the sulphur content in the slag is low. This oxygen potential will again be able to oxidize some iron: Fe + O ? Fe2+ + O2- and an increase in the iron content of the slag will be observed. Adding up eqs 1 and 3 one obtains: S + Fe ? S2- + Fe2+ The net effect is thus in harmony with the experimental observation but is obtained without assuming any close ties between the sulphur and iron atoms during the process. Furthermore, it follows from eqs 1 and 2 that when the sulphur content in the slag increases, and equilibrium with C and CO is finally approached, the local oxygen potential at the metal-slag interface will decrease, and the iron in the slag will be reduced back into its metallic state. C. E. Sims-—The data and conclusions presented in this paper are thoroughly convincing in establishing the mechanism of sulphur transfer from iron to slag as in a blast furnace. The evolution of gaseous CO in step 3 of the reactions given on p. 1112 makes the process virtually irreversible. Assuming that the process is similar in slag-metal systems other than in the blast furnace, it is readily seen why free CaO and re-ducing conditions so greatly favor desulphurization. On the other hand, the very effective desulphurization obtained in oxidizing slags when strongly basic, must be attributed to the relatively high stability of CaS as compared to FeS. The ease and simplicity with which the reactions of classic chemistry agree with the experimental data and explain the mechanism is noteworthy. The concept of molecules of FeS, soluble in both phases (metallic iron is not soluble in the slag), migrating from the iron to the slag and there reacting with CaO, which is soluble only in the slag phase, is clear and uncomplicated. This is likewise true for step 3. Those who would deny the existence of molecules or molecular-type combinations in liquid iron, must strain to provide a mechanism so lucid. In the absence of molecules, the Fe and S exhibit a remarkable collusion. L. S. Darken—The investigation and interpretation of rate phenomena in the range of steelmaking temperatures is a difficult task. Most of the laboratory investigations of steelmaking reactions have been concerned with equilibrium. Having determined the equilibrium, our attention naturally focuses next on the mechanism and rate of approach to equilibrium. The authors seem to have contributed substantially to our understanding of these factors for the case of sulphur transfer. I should like to ask the authors whether they consider that the sulphur transfer reaction is diffusion controlled as many high-temperature reactions seem to be. If so, it would seem reasonable to suppose that the slow diffusion step of the process is the transfer across a pseudo-static layer or film similar to that considered in heat flow problems. As the diffusivity and fluidity are smaller for the slag than for the metal, it may tentatively be assumed that the sulphur gradient exists in a thin layer in the slag adjacent to the slag-metal interface and that the metal and the main mass of slag are each maintained uniform by convection. On this basis the amount of sulphur transferred across unit area per unit time is D p (?S%)/100 ?1, where D is the diffusivity, p the density, (?S%) the difference in percent sulphur on the two sides of the layer, and ?l is the layer thickness. At the beginning of the experiment the main body of the slag and hence one side of the layer contains no sulphur; therefore (?S%) may be replaced by (S%), the sulphur content of the slag at the slag-metal interface, which in turn is equal to L[S%] where [S%] is the sulphur content of the metal and L is the distribution coefficient. The rate of transfer thus becomes DpL[S%]/100 ?l, which the authors designate K[S%]. Equating these two quantities and setting D = 10-6 cm2 per sec, p = 3 g per cm3, L = 40, and K = lo-+ g cm-2 sec-1, it is found that ?l, the film thickness, is about 0.01 cm—a value of the order of magnitude of that found in heat transfer problems in liquids. The uncertainty of the numerical values used leaves much to be desired, but at least it can be said that this calculation tends to support the proposed model involving diffusion through a film. Although this does not seem to affect the general argument, I should like to call attention to the fact that the diffusivity3 of sulphur in hot metal is found (on conversion of units) to be about 10-4 cm2 per sec rather than 104 cm2 per sec as stated by the authors. The three equations written by the authors to express the steps in the overall process of sulphur transfer may alternatively be written ionically as only two Fe + S = Fe++ + S-- Fe++ + O-- + C (graphite or metal) = CO (gas) + Fe where the underscore is used to designate the metallic phase; ionic species are slag constituents. After the authors have so neatly demonstrated that iron and sulphur transfer together (at least initially), this fact seems almost self evident; from eq 4 it is seen that if sulphur acquires a negative charge during transfer

Jan 1, 1951

By H. K. Birnbaum

The effect of 1ow-temperature stabilization anneals on the structure of the 0 phase Au-Cd alloys and on the diffusionless transformations observed in these alloys was examined by X-yay diffraction techniques. A phase separation in the ß-phase region was proposed to account for the experimenta1 results. The effects of quenching from elevated temperatures on the transformation behavior of these alloys were shown to be consistent with the proposed mechanism. IT has been shown that the high-temperature ß phase (CsCl structure) of the Au-Cd alloy system transforms to a phase having an orthorhombic (D2) ß&apos; structurel1-3 for compositions near 47.5 at. pct Cd and a tetragonal (4/m, m, m) ß" structure* in the vicinity of 50.0 at. pct Cd. Both transformations are diffusionless, crystallographically reversible, and occur on cooling at about 60° and 30°C respectively. The temperature interval from the beginning to the end of the transformation is of the order of 5°C in each case. Although the transformations are normally athermal, some of them have been reported to occur isothermally.= wechsler6,7 has shown that the effects of quenching a 49.0 at. pct Cd alloy from elevated temperatures are consistent with the retention of a nonequilibrium number of lattice vacancies. Annealing of these quench effects results in a broadening of the X-ray reflections.8 After a suitable quench, the 47.5 at. pct Cd alloy transforms to a phase having not the p&apos; orthorhombic structure but another structure which has properties similar to that of the ß" tetragonal structure.5.9 This change in the type of transformation has also been obtained after long anneals in the ß-phase region at about 70oC10 The present investigation was primarily concerned with the structural changes accompanying the above transformation phenomena. The change in transformation product and accompanying physical changes during an anneal in the ß phase have been termed stabilization effects. Experimental Procedure —The results reported in this investigation were obtained with the use of a Norelco diffractometer fitted with a temperature-controlled cryostat. The specimen temperature was controlled to better than ± 0.l°C during the measurements. CrKa radiation monochromated electronically with the use of a scintillation counter and pulse height analyzer was utilized. Specimens containing 47.5 and 50.0 at. pct Cd were prepared by sintering filings obtained from homogenized ingots of the proper alloy composition. (Gold of 99.999 pct purity and cadmium of 99.98 pct purity were used). All heat treatments were carried out with the specimens capsulated in vacuum ( < 10 % mm Hg) or in a He-H gas mixture. The quenching technique used in these experiments was to drop the pyrex capsule which contained the specimen from the annealing furnace into water, the temperature of which was controlled. The pyrex capsule shattered on contacting the water resulting in a relatively rapid quench. After the heat treatment, the specimens were mounted in the diffractometer and were left undisturbed in the diffractometer specimen holder during each sequence of measurements. EXPERIMENTAL RESULTS A) Low-Temperature Annealing—The transformations which were considered "normal" for these alloys were those obtained athermally during furnace cooling at approximately 50°C per hr after an elevated temperature anneal. Under these experimental conditions, the specimens were observed to transform to phases having structures whose diffraction patterns could be indexed as the ß&apos; orthorhombic structure for the 47.5 at. pct Cd and as the 0" tetragonal structure for the 50.0 at. pct Cd alloys. The transformation temperatures on cooling were approximately 60" and 30°C, respectively. Under the "normal" conditions both transformations were observed to go to completion, i.e., the entire volume of the ß phase was transformed to the product phase. In some specimens an extremely weak ß 110 reflection was observed at 20°C indicating that a small amount of retained ß was present. The effect of low-temperature annealing on the nature of the diffusionless transformations was examined for the 47.5 and 50.0 at, pct Cd alloy. The specimens were annealed in evacuated capsules at temperatures in the vicinity of 600°C (as specified in Table I) for 24 hr and were then cooled to 100°C at a rate of 50°C per hr. The specimens were then removed from the capsules and mounted in the diffractometer without allowing the specimen temperature to drop below 80°C. Annealing at the low temperatures was accomplished in the diffractometer by means of the cryostat which was mounted around the specimen. During the low-temperature anneals the lattice parameter, integral breadth of the reflections, and ratios of the integrated intensities of the fundamental and super lattice reflections for the 0 cubic phase were periodically determined. After annealing for the required time, the specimens were slowly cooled in the diffractometer and the diffraction patterns were recorded as a function of temperature. The specimens were cooled until the phase transformations were completed, following which the specimens were heated and diffraction

Jan 1, 1960

The first session was held in the rooms of the American Philosophical Society, on Tuesday evening, February 26th. The President, Dr. T. Sterry Hunt, called the meeting to order, and after a few introductory remarks concerning the importance of theoretical and speculative science, which often involves principles of the highest economic value, and, more than all that, serves to enlarge our conceptions of the universe, and ennoble us, by the cultivation which it affords to our most exalted faculties, proceeded to discuss some points in the chemistry of the atmosphere. It is known that there is in the crust of the earth a great amount of oxidized carbon, not only in the shape of coal, but also in the graphite or plunlbago of the crystalline rocks, in the various bituminous shales or pyroschists, which are found in all succeeding rock-formations, and also in the forms of bitumen and petroleum. All the analogies of nature lead us to conclude that these various carbonaceous substances have had an organic origin, and have been generated by the deoxidation of carbonic acid, a process effected by the growing plant, and attended with the liberation of oxygen. He showed that the carbon of a layer of coal covering the whole earth&apos;s surface to the thickness of one meter, would, in its production from carbonic dioxide, liberate an amount of oxygen equal to that now present in our atmosphere. But bituminous coal contains also a large amount of hydrogen, derived from the deoxidation of water, which implies the liberation of a farther portion of oxygen. The amount from this latter source would equal, for the various coals and asphalts, from one-eighth to one-fourth, and, for the petroleums, onehalf of that set free in the deoxidation of the carbon which these hydrocarbonaceous bodies contain. From what we know of the composition of the stratified rocks, it is probable that they include an amount of deoxidized carbon and hydrogen many times greater than that contained in a layer of coal one meter in thickness, and, consequently, that the disengaged oxygen in past ages must have far exceeded that now present in our atmosphere. To this must be added

Jan 1, 1879

The Secretary of the Treasury, acting through the National War Savings Committee, soliciting the support of patriotic associations in America in the sale of War Savings Stamps, has addressed the following letter to the President of the Institute: It is particularly desirable to have you urge the members of your association to give their assistance wholeheartedly, and to this end we urgently request that you write a letter to each of your members, outlining the aims of this campaign. That you may more easily draft your letter, we mention a few things in which your members could render a special service. Agencies and Sales Stations.-We desire immediately to establish several hundred thousand agencies and sales stations. It is as easy to sell a War Savings Stamp as it is in ordinary postage stamp, and we have launched a great drive to establish sales stations everywhere. The plan is simplicity itself! Your town, city, county or State Director can furnish you with supplies, posters and publicity matter. You can get the stamps from your post office or bank. Such stations should be at every pay window of manufacturing, industrial and mercantile establishments, and at every retail counter in the country. These stamps should be the easiest bought merchandise in the world, and when these agencies are established this end will have been accom-plished. Therefore, please lay extra pressure on the thought of immediately establishing these sales stations.

Jan 3, 1918

By Ira N. Holli

A meeting of Engineering Council was held on Thursday, Jan. 22, 1918, at the Engineering Societies Building, New York. Present: Chairman Ira N. Hollis (A. S. M. E.); Dr. Charles Warren Hunt, Alex. C. Humphreys and F. H. Newell (A. S. C. E.); B. B. Lawrence and .J. Parke Charming (A. I. M. E.); Charles Whiting Baker, D. S. Jacobus, and George, J. Foran (A. S. M. E.) ; H. W. Buck, E. W. Rice, Jr., N. A. Carle, C. E. Skinner and Comfort A. Adams (A. I. E. E.) ; Clemens Herschel and Calvert Townley (United Engineering Society); also, by invitation, D. W. Brunton, Chairman, War Committee of Technical Societies of Engineering Council. Of the several actions taken at this meeting, the following are selected as being of most general interest. Chairman-Baker-presented a resolution on the conduct of the war, to which objections were made. It was referred to a special-committee; Charles Whiting Baker, Charles Warren Hunt, and Calvert Townley, for re-drafting and presentation later in the meeting. The revised resolution submitted by this committee led to further discussion and as no agreement could he reached, the matter was laid on the table.

Jan 3, 1918

By F. Keller

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 eighteenth1 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 com-pleted 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 Mg2Si caused a noticeable decrease in the solid solubility of Mg2Si in aluminum. A more recent investigation3 in these laboratories showed that the solid solubility of Mg2Si 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.

Jan 1, 1936

By PDF

C. 0. FAIRCHILD, Washington, D. C. (written discussion*).-Referring to the paragraph entitled "Effect of change in temperature of absorbing glass on its transmission," Dr. Foote and the writer have been using, since

Jan 11, 1919

CHARLES KIRCHHOFF, Chairman. ALBERT SAUVEUR, Vice-Chairman. A. A. STEVENSON, Vice- Chairman. HERBERT M. BOYLSTON, Secretary, Abbot Bldg., Cambridge, Mass. John Birkinbine, J. Esrey Johnson, Jr., Felix A: Vogel, William H. Blauvelt, William Kelly, Leonard Waldo, James Gayley, Richard Moldenke, William R. Walker, Henry D. Hibbard, Joseph W. Richards, William R. Webster. Henry M. Howe, E. Gybbon Spilsbury, Frederick W. Wood. Robert W. Hunt, A. A. Stevenson is appointed an additional Vice-Chairman of the Committee. He will serve as Acting Chairman during the absence abroad of Professor Sauveur. For the meeting of the Institute which is to be held in New York City, Oct. 16 and 17, 1913, the following papers are now assured

Jan 7, 1913

By F. Garofalo

It has been shown by various investigators that during constant stress creep the dependence of minimum creep rate, 6,, on stress, o, is given by em = A onat low stress levels, md by 6, = A&apos; exp [ß s] at high stress levels. In these relations A, n, A&apos;, and ß are constant at constant temperature. A single relation has been found which satisfies conditions for both high and low stresses and agrees well with experimental results. This relation is 2, = AN (sinh a s)n, where A" is a constant at constunt temperature and a = p/n. This relation also satisfies the linear relation, 6, = k s, found at temperatures near the melting point at low stresses. EXPERIMENTAL creep results have led to a number of empirical relationships between minimum creep rate, 6,, and the applied stress, s. Under conditions of constant stress it is generally found that at low-stress levels,&apos;-&apos; the dependence of minimum creep rate is given by 6, = Asn. At high-stress levels&apos;74 the experimental results fit the relation, 6, = A&apos; exp [po l. In these relations A, n, A&apos; and ß are constant at constant temperature. A model based on climb-of-edge dislocations from a pile-up array leads to a relation similar to that found experimentally at low stresses.&apos; On the other hand. theories based on chemical-reaction rate,5 nonconservatively moving dislocation jogs, and jog migration and climb-of-edge dislocations4 lead to a relation similar to that found experimentally at high stresses. No difference in mechanism between low and high stress levels has been clearly defined; it is questionable whether such a difference really exists. In any event, the major argument usually given in substantiation of a change in mechanism from low to high stresses is that no single relation exists for defining the stress dependence of the creep rate over wide ranges in stress. However, such a relation has been found and is of the form, dm = A" (sinh a s)n, where A" is a constant at con- stant temperature and a = ß/n. This relation agrees well with experimental results over wide ranges in stress and temperature for copper, aluminum, an A1-3.1 pct Mg alloy, and an austenitic stainless steel. STRESS DEPENDENCE OF MINIMUM CREEP RATE At low stress levels the minimum creep rate, gm, depends on the stress, 0, under conditions of constant stress creep through the relation em=Aon [1] The quantities A and n have been defined previously. In the range in which this relation applies, a linear dependence is found in a log em,-log o plot. Above the stress range of application of relation [I], the minimum creep rate increases much mar; rapidly than predicted by relation [I]. This behavior is shown in Fig. 1 for a series of creep tests on copper4 at various temperatures ranging from 673 o to 973°K. Relation [I] is satisfied at the lower stresses, although the results at 973°K are quite limited. In all cases the transition beyond the applicable range of relation [I] is a gradual one indicating no abrupt change in mechanism. For all test temperatures, values of n have been determined from the results in Fig. 1. These are reported in Table I under Alog tm/hlog o. At high stress levels the stress dependence of minimum creep rate under conditions of constant stress is given by im = A&apos; exp [ß a] 2] All factors have been defined previously. In a log em-0 plot, relation [2] predicts a linear function. Experimentally, a pronounced deviation from the prediction of relation [2] is found at lower stresses. As the stress is lowered, the minimum creep rate decreases more rapidly than predicted by relation [2]. This shown for copper in Fig. 2. Again it is found that the transition from high to low stresses is gradual and no really sharp change is found. Values of p determined from the high stress results are given in Table I. The dependence of minimum creep rate on stress at constant temperature for all ranges in stress

Jan 1, 1963

(Under this heading will be published notes sent to the Secretary of the Institute of members or other persons introduced by members) Young mining engineer, and geologist, member, technical, graduate with four years&apos; varied mining experience in the West and Southwest as miner, surveyor and engineer. Past 18 months, work in mine geology, mapping and examinations. Would prefer assisting consulting engineer or work with exploration company in foreign service. Unmarried. Age, 28. No. 331. Member; aged 35, married, with 10 years&apos; experience in the Southwest, thoroughly competent to take full charge of mining and milling operations. Particularly fitted to handle either gold or tungsten producers. At liberty February 1. Will go anywhere. No. 340. A member wants a roving commission to examine old mines of the Mother Lode in. California, especially those which can be bought for their taxes. Some of these mines are reported to contain large quantities of low-grade ores which can now be treated at a profit. No. 341.

Jan 2, 1917

By W. L. Austin

The only essential difference among the three methods of collecting the precious metals from their low-grade ores by fusion is comprised in the nature of the vehicle in which those metals are concentrated. If lead- or coppper-ores are used, the processes are respectively lead- or copper-smelting; but when the sulphide of iron forms the matrix in which the gold and silver are collected, the process is known as pyritic smelting. The latter method presents rarely any advantages when lead- or copper-ores are available at rates which permit profitable treatment. Pyritic silver-smelting, defined by Percy as " the smelting of silver-ores, which are either free from lead or do not contain it in sufficient quantity to collect the silver, in conjunction with pyrites, in order to produce a regulus in which the silver may be concentrated," is not, as the name would imply, confined to ores of this metal alone, but embraces auriferous silver-ores, or even gold-ores simple. This method of collecting the precious metals from lowgrade dry ores, employed at Freiberg by Barthel Kohler in 1585, does not appear, up to the present, to have been introduced into this country on a working scale. And yet the possibility of getting rid in a single operation of all the earthy or siliceous gangue of a lowgrade ore and concentrating the precious metals in a matte without loss of lead (which includes gold and silver) by slagging, or volatilization, at the same time producing a highly siliceous slag, very nearly if not quite as clean as is usual in lead-smelting, certainly commends itself. In some parts of the country, owing to the com-

Jan 1, 1888

By T. Saburi, C. M. Wayman

The massive and martensitic transformations in ß Cu-Ga alloys were studied by optical microscopy and by transmission electron microscopy and diffraction. These types of transformation are distinct and do not merge into one another. An internal fine structure due to stacking faults was found in both the massive phase (m) and the martensite, but the origin of the faults is believed to be different in each case. The faults in the martensite are due to the lattice invariant or "second" shear of the phenom-enological theory, while those in the are probably growth faults and deformation faults arising from the transformation volume change. Evidence is presented for ordering in the ß phase prior to transformation into martensite, and the crystal structures of and ß&apos; and ßi martensites are discussed. THE results from some previous investigations1,2 have led to the suggestion that martensitic and massive transformations have certain common characteristics. It presently seems established that massive transformations like martensitic transformations are essentially diffusionless,1,2 but unlike martensitic transformations, when a new phase forms massively there is no shape change or surface relief.= If the massive-type transformation is crystallographically similar to martensitic transformations, one would expect a fine structure as a result of the lattice invariant shear4 which is a part of the transformation mechanism. The existence of such a fine structure (i.e., slip, twinning, or faulting), if any, can be verified by transmission electron microscopy, and thus the present investigation was undertaken to compare the internal structure of massively and martensitically formed phases in Cu-Ga alloys which were derived from a parent of the same composition. The transformation characteristics of ß Cu-Ga alloys were also studied. The bcc ß phase in the Cu-Ga system, Fig. 1, is stable above 616oc.&apos; Depending upon the cooling rate, ß Cu-Ga alloys can undergo three different types of phase transformations. The ß phase of eutectoid composition (23.7 at. pct Ga) decomposes into the ? phase (hcp) and the phase (complex cubic) by means of a eutectoid reaction. When the cooling rate is increased so that the decomposition of 0 into [ and ? is suppressed, the ß phase transforms into a nonequilibrium hcp phase, herein denoted ?m by a process of very rapid growth called a "massive" transformation. At even faster quenching rates the massive transformation can be suppressed and the ß transforms martensitically. Massive transformations, apparently similar to those in the Cu-Ga system, have also been studied in the Cu-Zn2,6-8 and Ag-Cd systems.9 Definitive characteristics if the Massive Transformations in 0 Cu-Ga Alloys1 1) The most remarkable feature of the massive transformation in Cu-Ga is that there is no bulk composition change on transformation. According to Massalski,1 the resulting [, phase is a supersaturated extension of the equilibrium [ phase. The lattice parameters continue the trend exhibited

Jan 1, 1965

By N. C. Nissen, J. A. Thomas, A. Illis, K. N. Subramanian

Successful miniplant and laboratory testwork has indicated that high purity selenium can be produced from copper refinery slimes. The recovery technique fits into existing unit operations, and the selenium recovery in the new process was close to 99%. This recovery virtually eliminated any selenium being processed through the smelting stage. In addition, miniplant tests conducted at Inco Metals Co.&apos;s J. Roy Gordon Research Laboratory in Mississauga, Ontario, have demonstrated the reliability of the process with respect to extractions, product quality, filtration characteristics, and effluent disposal. Inco&apos;s copper refinery at Copper Cliff, Ontario, produces about 500 t/d of copper with the anode slimes fall typically averaging 0.5% of the throughput. Investigations relating to the treatment of slimes within Inco&apos;s R&D have been conducted on several occasions since 1959, when the available alternatives such as acid or alkaline pressure leaching, aqueous or high temperature chlorination, roasting, smelting, etc., were considered. Interest in slimes processing was revived recently to meet increasingly stringent environmental standards and to replace equipment of a relatively old plant.

Jan 11, 1978

By William B. Phillips

In connection with the address of our late President, Mr. Joseph D. Weeks, delivered at the Pittsburgh meeting, in February, 1896,* I venture to believe that a circumstance which came recently to my notice may possess some historical interest. Several years ago I spent some months in Western Kentucky

Jan 1, 1899