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By J.W. Halley

The effects of tin on steel have become increasingly important because of the necessity of using poorly detinned scrap, tin cans, and terne plate, in the open hearth. Since a tin can contains about 1.5 per cent tin, it would be possible to have up to 0.75 per cent tin in steel made with a 50 per cent scrap charge. In order to use tin-containing scrap, it is necessary to know the effect of tin on various grades of steel. The following investigation is by no means comprehensive but covers a number of steels in which tin content is important. Published Work A number of investigations of the effects of tin on rolling quality and physical properties have been published. It has been found that tin increases strength and hardness and reduces ductility and notched impact resistance. The decrease' in ductility and notched impact resistance becomes more marked as the carbon decreases. McKimml found no change in Olsen ductility, Kockwell hardness, yield strength, tensile strength or elongation in cold-reduced strip containing up to 0.124 per cent tin. A tin content of 0.1j per cent gave difficulties in rolling and increased the hardness but 0.21 per cent tin showed no change in properties from material containing very little tin. No explanation of this contradiction is offered. Andrew and Peile2 investigated steels containing 0.10 to 0.25 per cent carbon and up to 0.63 per cent tin. They found an increase in tensile strength of from 100 to 200 lb. per sq. in. for each 0.01 per cent tin on normalized samples. The elongation and reduction of area were decreased and the notched impact resistance was reduced markedly. Quenched and drawn samples did not show embrittling if water-quenched from the draw temperature of 1148°F. (620°C.). They could find no evidence of tin under the microscope. Whitely and Braithwaite3 investigated the effect of tin on rail steel containing 0.55 to 0.60 per cent carbon. They found that 0.08 per cent tin caused a marked decrease in elongation, notched impact resistance and the degree of bend. The tensile strength was increased in some tests and not in others. Bolsover and Barraclough4 investigated the effect of tin up to 0. 50 per cent on a 0.35 per cent carbon steel and on several alloy steels with from 0.30 to 0.40 per cent carbon. They found a comparatively uniform decrease in notched impact resistance with increasing tin on quenched and drawn samples. If the samples were quenched from the drawing temperature or reheated to the drawing temperature and quenched, the embrittling was much less severe. Steels containing molybdenum suffered much less embrittlement than other steels. Experimental WoRk Effect of Tin on Low-carbon Rimmed Steel Increasing quantities of tin were added to four ingots of a heat of the following ladle analysis: carbon, 0.08 per cent; manganese, 0.39; phosphorus, 0.009; sulphur, 0.025.

Jan 1, 1943

By J. W. Halley

The effects of tin on steel have become increasingly important because of the necessity of using poorly detinned scrap, tin cans, and terne plate, in the open hearth. Since a tin can contains about 1.5 per cent tin, it would be possible to have up to 0.75 per cent tin in steel made with a 50 per cent scrap charge. In order to use tin-containing scrap, it is necessary to know the effect of tin on various grades of steel. The following investigation is by no means comprehensive but covers a number of steels in which tin content is important. Published Work A number of investigations of the effects of tin on rolling quality and physical properties have been published. It has been found that tin increases strength and hardness and reduces ductility and notched impact resistance. The decrease' in ductility and notched impact resistance becomes more marked as the carbon decreases. McKimml found no change in Olsen ductility, Kockwell hardness, yield strength, tensile strength or elongation in cold-reduced strip containing up to 0.124 per cent tin. A tin content of 0.1j per cent gave difficulties in rolling and increased the hardness but 0.21 per cent tin showed no change in properties from material containing very little tin. No explanation of this contradiction is offered. Andrew and Peile2 investigated steels containing 0.10 to 0.25 per cent carbon and up to 0.63 per cent tin. They found an increase in tensile strength of from 100 to 200 lb. per sq. in. for each 0.01 per cent tin on normalized samples. The elongation and reduction of area were decreased and the notched impact resistance was reduced markedly. Quenched and drawn samples did not show embrittling if water-quenched from the draw temperature of 1148°F. (620°C.). They could find no evidence of tin under the microscope. Whitely and Braithwaite3 investigated the effect of tin on rail steel containing 0.55 to 0.60 per cent carbon. They found that 0.08 per cent tin caused a marked decrease in elongation, notched impact resistance and the degree of bend. The tensile strength was increased in some tests and not in others. Bolsover and Barraclough4 investigated the effect of tin up to 0. 50 per cent on a 0.35 per cent carbon steel and on several alloy steels with from 0.30 to 0.40 per cent carbon. They found a comparatively uniform decrease in notched impact resistance with increasing tin on quenched and drawn samples. If the samples were quenched from the drawing temperature or reheated to the drawing temperature and quenched, the embrittling was much less severe. Steels containing molybdenum suffered much less embrittlement than other steels. Experimental WoRk Effect of Tin on Low-carbon Rimmed Steel Increasing quantities of tin were added to four ingots of a heat of the following ladle analysis: carbon, 0.08 per cent; manganese, 0.39; phosphorus, 0.009; sulphur, 0.025.

Jan 1, 1943

By Alfred Weiss

Approximately 850 delegates from 24 countries met in Tokyo, Japan, May 24-27, for the second MMIJ-AIME Joint Meeting in 55 years, to exchange technical knowledge and experience in the fields of exploration, mining, metallurgy and petroleum engineering. The first such meeting was held in 1917 in Kyoto, Japan. Although the Mining and Metallurgical Institute of Japan was the sponsor, the entire meeting (machinery exposition, technical program, and tours) was a joint effort of the two institutes.

Jan 7, 1972

By G. R. Fritterer

Investigators in the field of temperature measurement have long sought a thermoelectric couple fulfilling the following requirements: 1. It should be useful up to and including high industrial temperatures; i. e., 1000 to 1800 C. 2. Its thermoelectric variation with temperature should be linear and be maintained after heating to high temperatures for long periods of time. 3. It should be reproducible; i. e., different couples of the same elements should have similar calibration curves. 4. Its thermoelectric power should be large so as to allow the industrial use of rugged recording instruments. 5. Chemical reactions with, and physical changes within the elements of the couple should not alter its calibration. No thermocouple proposed to date exhibits simultaneously all of these characteristics, whereas the couple about to be described fulfills all requirements to a satisfactory degree. New Thermoelectric Materials A thorough survey of the literature on thermoelectricity revealed that present-day thermocouples could not meet the specifications mentioned above because their thermoelements are metallic. Metals have a marked tendency to deteriorate chemically and their melting points limit their use to low temperatures. Refractory substances, however, are usually resistant to chemical attack and are quite stable at high temperatures. Hence a survey of refractory substances having thermoelectric possibilities was made. One class of thermocouples considered was that in which carbon and a carbide of some metal or nonmetal were the thermoelements. Previous investigators neglected to study this field but certain recommendations were made by them for the use of couples in which carbon served as one element. These proposals are listed in Table 1. The couples suggested are unsatisfactory because of their low thermoelectric powers, the low melting points of their metallic elements, etc. The

Jan 1, 1933

By R. E. Head

Some mixtures of sulphide and oxide ores from the Tintic district in Utah are of a sufficiently good grade to be shipped to the smelter without beneficiation. In mining this type of ore, however, a material tonnage of ore of a similar composition but of lower grade is obtained. It is a question of economics whether such ore should be shipped with a certainty of a small return or concentrated if that would yield a sufficiently increased return to amortize plant construction and upkeep and yield a higher rate of profit than at present. It may be assumed that the tonnage of this borderline ore is constantly increasing and that eventually it will attain such proportions as to justify plans for milling on a relatively large scale. Under existing conditions, the producer of mixed sulphide and oxide ores is not greatly concerned about the physical characteristics of his ore or of its mineralogical complexities, since his contract with the smelter calls for payment on the basis of chemical analysis. When concentration is contemplated an entirely different picture is presented. Percentages of valuable metal content must then be con-sidered in terms of minerals, for it is in the form of minerals that recoveries are made and losses sustained. In describing the performance of a given flotation mill and reagent combination, it may be stated as a generality that a specific percentage recovery of valuable elements is made. Technically, however, the concentrator is really constructed and the reagents are selected to recover the valuable minerals. These considerations must be given prominence in discussing borderline ores from the Tintic district because of their physical characteristics and mineralogical composition. Because of these peculiarities they may be justly termed complex, since their lead, silver, and copper contents are each represented by two or more minerals of different chemical composition and presenting widely divergent physical properties. This paper sets forth the results of a microscopic study of a type of borderline ore from the Tintic district that is now being treated by direct smelting. A

Jan 1, 1939

By R. E. Head

Some mixtures of sulphide and oxide ores from the Tintic district in Utah are of a sufficiently good grade to be shipped to the smelter without beneficiation. In mining this type of ore, however, a material tonnage of ore of a similar composition but of lower grade is obtained. It is a question of economics whether such ore should be shipped with a certainty of a small return or concentrated if that would yield a sufficiently increased return to amortize plant construction and upkeep and yield a higher rate of profit than at present. It may be assumed that the tonnage of this borderline ore is constantly increasing and that eventually it will attain such proportions as to justify plans for milling on a relatively large scale. Under existing conditions, the producer of mixed sulphide and oxide ores is not greatly concerned about the physical characteristics of his ore or of its mineralogical complexities, since his contract with the smelter calls for payment on the basis of chemical analysis. When concentration is contemplated an entirely different picture is presented. Percentages of valuable metal content must then be con-sidered in terms of minerals, for it is in the form of minerals that recoveries are made and losses sustained. In describing the performance of a given flotation mill and reagent combination, it may be stated as a generality that a specific percentage recovery of valuable elements is made. Technically, however, the concentrator is really constructed and the reagents are selected to recover the valuable minerals. These considerations must be given prominence in discussing borderline ores from the Tintic district because of their physical characteristics and mineralogical composition. Because of these peculiarities they may be justly termed complex, since their lead, silver, and copper contents are each represented by two or more minerals of different chemical composition and presenting widely divergent physical properties. This paper sets forth the results of a microscopic study of a type of borderline ore from the Tintic district that is now being treated by direct smelting. A

Jan 1, 1939

By G. R. St. Pierre, R. D. Blackburn

Oxygen contents of' liquid-iron alloys saturated with oxides are analyzed. Minimum points observed in particular Fe-X-O systems can be predicled by a simple extension of first-order interaction methods. If minimum oxygen content occurs at N; where r is the ratio of metal to oxygen in the oxide phase. RECENTLY, wisher' reported on solubility measurements of A1203 in liquid iron at 1580°C which support the earlier work of d'Entremont, Guernsey, and chipman2 and Gokcen and Chipman. Swisher's diagram is reproduced in Fig. l. Minimum points in oxide solubilities have also been found in the Fe-Cr-0 system,4 Fig. 2, and the Fe-Ti-0 system,' Fig. 3. Minima positions can be used to confirm approximately the measured first-order interactions, &, cgr, and E&~, in liquid iron and to deduce compositions of components of constant activity in the oxide phases. Consider the solution of Alz03 in liquid iron: for which an equilibrium constant can be written as: differentiating Eq. [2] with respect to Na~, the atom fraction of &l in the metallic solution, and noting that If the activities of Al and 9 are expanded by a first-order interaction model, then:

Jan 1, 1969

By N. Van Wingen

EFFECTIVE sand permeabilities can be ascertained from core analysis if the laboratory data are compensated to allow for the presence of connate or residual water. Such adjustments can be made by applying empirically derived correction factors. Effective sand permeabilities can be estimated also from analytical studies of field depth-pressure measurements. In one method the time rate of pressure build-up after a well is shut in from steady-state flow is required, and in the other the direct measurement of a steady-state rate of flow and the corresponding equilibrium pressure. The results of the investigation discussed in this paper demonstrate that these methods for determining mean effective sand permeabilities can be correlated.

Jan 1, 1942

By R. R. Nash, W. F. Sheely, E. D. Levine

ThiS note reports on the variation with temperature of critical stress for basal slip of binary solid-solution single crystals of indium and of thorium in magnesium. PROCEDURE Alloy single crystal spheres were acid machined to 3/8-in. diam cylinders with the basal planes of the crystals normal to the cylinder axis and then annealed at 810°K. Stress was applied parallel to the slip system, (0001) [1120]. Experimental details will be presented in another paper.' Two nearly equivalent' techniques of stressing were used. Stress on the magnesium-indium alloy crystals was increased by 1 g per sq mm at 1-min intervals, and the critical flow stress was defined as the lowest stress to pro-

Jan 1, 1960

By Philip D. Wilson

IT has been my privilege to read the article prepared by R. S. Dean entitled "Production of Alumina from Low-Grade Domestic Materials" which appears on another page of this issue. Dr. Dean should be congratulated on the preparation of such an erudite and scholarly dissertation on bauxite and on the work which the Bureau of Mines has been doing in connection with the development of processes to use low-grade domestic materials.

Jan 1, 1943

By C. S. Roberts

THE advent of a sensitive X-ray method of analysis recently has allowed the determination of retained austenite in amounts as low as 0.3 pct.' As a result this phase has been found in quenched low carbon steels where its presence has not been generally suspected. In the course of a study of the tempering process,' retained austenite determinations were made by the X-ray method on a series of high purity Fe-C alloys and plain carbon steels. The chemical analyses of these materials and details of the hardening procedure are given in Table I. Results were obtained after quenching to 72°F (22°C) and — 321 °F (—196°C). Austenitizing temperatures were between 100" and 150°F above A, or Acm. All proeutec-toid cementite or ferrite was in solution. The combination of the results with those of Averbach, Castleman, and Cohen,' and earlier results of Esser

Jan 1, 1954

By R. E. Hummel, J. W. Koger

SINCE the first report about a diffusionless transformation of bcc p1 brass to tetragonal p" in 1936 by Kaminski and Kurdjumov,' a series of papers have been published about this transformation, mainly dealing with the temperature range of the martensitic-start temperature (M,) and with the crystallographic structures of the parent and product phases .s In the

Jan 1, 1969

By H. S. Hanna, C. Rampacek

The problems and limitations encountered in the Physical beneficiation of the Appalachian Red Iron Ores are discussed. Two major problems are identified - the high phosphorus content and the fine dissemination or encapsulation of mineral impurities in the iron-bearing minerals. A process that combined extreme fine grinding techniques with magnetizing roasting or flotation-separation methods is suggested. By these methods, concentrates assaying 60-61 % Fe, exceeding the widely accepted upper limit of 56% Fe set for these ores, were produced with 75-90% iron recovery. Moreover, it was shown that the phosphorus content of these concentrates could be reduced from 0.25% to 0.03% phosphorus by acid leaching. A brief discussion on production costs based on current and future developments in iron ore processing is given.

Jan 1, 1983

By P. Barnes

EXACT accounts have been kept of the cost of these chimneys, and it may be a matter of some possible interest that the plans and details of cost should be laid before the Institute. The statement of cost herewith submitted does not give minute particulars of the weights or quantities of material used, although these are noted upon the company's books.

Jan 1, 1876

By Francis Laur

BAUXITE, at first considered as a mineralogical curiosity without importance, now attracts daily increased attention from mineralogists, geologists, and manufacturers. The metallurgy of aluminum, which has entered with the advent of electrolysis upon a new phase within the last few years, requires every day larger quantities of pure alumina, and this can only be obtained from bauxite, which is, of known substances, the richest in free alumina. Bauxite has been mined since 1872 in France, whereabout 200,000 tons have been produced, and where, as a natural consequence, its deposits, qualities, and applications have become known. Within a few years past, discoveries of important deposits of bauxite have been made in the United States and Canada, and this almost entirely new subject has thus acquired an additional interest for the mining engineers and metallurgists of the American continent. A brief summary of the available data concerning it appears likely, therefore, to be appropriate and valuable.* I.—HISTORICAL. It was in 1821 that the famous chemist Berthier discovered at Baux (Bouches du Rhône) a hydrate of alumina (varying from 66 to 79 per cent. in its contents of the oxide) mixed with silica and

Jan 1, 1895

By F. W. Bradley

This chapter on the Alaska Juneau mill is intended to make clear that "choice of methods," or the selection of proper methods, is the first essential step in launching a new enterprise; and to illustrate that when entering into new country where local conditions and physical features are new or strange to an engineer, he should respect the practices already adopted and followed in meeting peculiar conditions in these new countries that may seem strange to a casual visitor. For example, Americans going into Malay Peninsula with their most up-to-date machinery for drilling placer prospect holes found their cost to total about $3 per foot; by adopting native methods, it was found the same work could be done for 50 cents per foot. Also, those not used to frozen road conditions in a country of arctic climate might scrape the snow off such a road and cause unending road troubles into the following spring and summer; while natives understanding local conditions would leave the snow on the road. So in the neighborhood of Juneau, Alaska, where successful gold-milling operations had been going on for

Jan 1, 1932

By C. P. Gazzara and

The modulus of elasticity and yield strength of commercially pure, annealed titanium sheet was investigated at room temperature as a function of strain rate and direction of loading. The value of E varied with direction of measuremeni in the sheet but was unaffected by strain rate in the range 0.04 x 10-to 10-2min-1. The yield strength increased with increase it2 strain rate and varied with specimen orientation. VALUES of the modulus of elasticity, E, in tension for commercially pure titanium have been reported at from 14 to 20Xl06 psi.' Reasons suggested for this variation have been a) composition, b) strain rate, c) texturing, and d) creep. For example, alloys of titanium with aluminum, manganese, and nitrogen have yielded modulus values of from 12.5 to 16.8 x lo6 psi at room temperature.' It was shown by Klier that the modulus in titanium plate was sensi-tive to strain rate. while Dotson and kattus meas- ured variations in E as the strain rate was increased from 3X to 60 min-l. For RC-7OA, 0.040-in. titanium sheet at room temperature Dotson and Kattus found that the average values of E, for specimens in the rolling direction, increased from 14.7 to 16.0 X lo6 psi as the strain rate increased. Simultaneously, the 0.2 pct yield strength increased from 74,700 to 95,700 psi for the same specimens. Differences in yield strength and E have been reported as a function of directionality in titanium sheet.= Dotson and Kattus report such an effect, and Feola6 found in annealed titanium sheet marked anisotropy in tensile strength, yield strength, reduction in area and elongation at room temperature, with

Jan 1, 1961

By Bert S. Sandell

Much has been said and written about the various uses of die castings, their applications in the various industries and their advantages and disadvantages. Examination of this literature, however, fails to disclose any data concerning the effect of temperature upon any of the physical properties of die-casting alloys. The uses and applications of die castings are so numerous, and of such a varied nature, that far too lengthy a manuscript would be required to list all of them. Brief mention of some specific cases will suffice to illustrate the temperature ranges in which certain die castings function. Automobile hardware, such as hub caps, door handles, radiator caps, etc., can be used as one example. Castings of this type are constantly exposed to varying climatic conditions, temperatures ranging from below zero to upwards of 100" F. Refrigerator parts, such as ice-cube trays, etc., form another example. Approaching the other temperature extreme, we encounter conditions such as are found in kitchens in which oven-heat indicator parts, cooking utensils, waffle grids, etc., embody use of die castings, where temperatures as high as 500" F. are often met with. Because of this variation in service temperatures, it was felt necessary to ascertain the effect of these temperatures upon the physical properties of die-casting alloys. The Charpy impact test was chosen first because of its simplicity, and because of the fact that brittleness is more likely to be objectionable in die castings than hardness or other physical properties. Alloys Investigated Two types of alloys were used in this investigation—zinc-base and aluminum-base alloys. Two alloys of each group were included. Those most generally employed in the industry at present were selected. Alloys A and B are of the same nominal composition, and correspond to A. S. T. M. alloy XXI, containing 4 per cent aluminum, 3 per cent copper, 0.1 per cent magnesium, and the balance zinc of 99.99 per cent

Jan 1, 1932

By E. B. Hunt, T. M. Geffen, C. R. Stewart, V. J. Berry

Laboratory data .show that the gas-oil ratio performance of non-uniform porosity limestones produced by solution gas drive is sensitive to producing rate and to fluid properties. Nan-uniform porosity limestones are those for which laboratcry solution and external gas drive tests yield considerably different relative permeability ratio characterislics. The oil recovery performance by solution gas drive depends directly on the number of gas bubbles formed. Laboratory rates of pressure decline, which are 100 to 10,000 times greater than normal field rates. cause the formation of an unusually large number of gas bubbles. This results in abnormally high oil recovery efficiencies. Since it is impractical to reproduce the number of bubbles formed under field conditions, laboratory solution gas drive data on non-uniform porosity limestones are therefore not directly applicable to field operations. However, certain laboratory data can be used to make a conservative estimate of field performance. The concepts presented in this paper indicate the possibility that increased field oil recoveries may he obtained from non-uniform porosity limestones by rap- idly reducing reservoir pressure for a short interval of time. It has yet to be established that significant improvements in oil recovery from such reservoirs can he realized by varying the pressure decline rate within limits possible in the field. However, the possibility that recovery may be increased in this manner warrants further study. INTRODUCTION Limestone reservoir rocks can be divided into two general classes according to the nature of their pore space. One class has a comparatively uniform pore system composed mainly of voids between grains of the rock (intergranular type porosity). The other class, in addition to having intergranular porosity, has a secondary pore system composed of combinations of solution cavities, fractures, etc., and is considered to have non-uniform porosity. It has been shown in a previous publication' that the laboratory measured gas-oil flow behavior of uniform type porosity limestones is essentially the same for a test simulating a field solution gas drive as for one simulating an external gas drive. For non-uniform porosity type limestones a significant difference in gas-oil flow behavior was found. More efficient behavior was

Jan 1, 1955

By Harry V. Welch

Early in the development of the art of metallurgy, it was noted that a distinct difference existed in the character, collection possibility and health hazard of the "smoke" from lead furnaces and those from copper plants. Zinc-plant fumes, although not so detrimental to health, were closely allied in nature to those of the lead works. In Cottrell plants, there are sufficiently distinct differences in operation and amount of construction between those for lead and copper to justify their consideration under separate headings; therefore, while the application of the process at copper-reduction works was covered by the writer some two years ago in the Transactions1,† this discussion will confine itself more distinctly to "fume" collection. General information on the process has been presented in numerous articles and by many authors: Cottre112, Schmidt3, Bradley4, Anderson6, Labbe6, Shiga7, Rathbun8. "Fume" may be defined as material, metal or nonmetal, elemental or compound, evolved as a vapor from a furnacing or chemical reaction and condensing, chilling or reacting within the gas stream to yield a solid form, and in this definition liquid particles are solids in a sense as distinguished from gases or vapors. Such condensed particles are of minute form, on the order of "smoke," and, for example, on the order of a few hundredths of 1 micron (1 micron = 1/25,000 in.) to perhaps 3 microns, with agglomerates, in relatively small proportions of many particles. Metallurgically typical fume products are lead compounds, oxides, carbonates and sulphates; elemental zinc, more commonly encountered as a fume particle of zinc metal with a surrounding "skin" of zinc oxide; arsenic, both metal and oxide and some of its more complex salts such as added sulphates as found in flue dusts; antimony, more particularly its oxide forms; and elemental sulphur, sometimes a troublesome product, in Dwight-Lloyd sintering-plant fumes. These products, particularly the elemental or lower oxide forms, have relatively appreciable vapor pressures at the existing operating temperatures as reported by Welch and Duschak9, Ingold10, Johnstonll, Millar12,13.

Jan 1, 1937