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By O. A. Knight

THE suppression of the austenite-martensite transformation that can be brought about by the addition of certain alloying elements, such as manganese or nickel, to plain carbon steel has been known for a long time, especially since Guillet's investigation at the beginning of this century. The extent to which the critical range is lowered depends upon the percentage and nature of the special element added. First the Ar1 point is lowered gradually, then at a certain percentage a sudden lowering to about 300° C. occurs. The addition of still larger percentages of the alloy may result in lowering the Ar1 point to room temperature or below, in which case the steel remains austenitic at room temperature, especially after rapid cooling. The effect of alloying elements of this general type on the lowering of the transformation temperature is well illustrated by Sauveur(1)§ in his Fig. 281a, reproduced here as Fig. 1. This type of curve is characteristic of both manganese and nickel though it requires about 2 1/2 times as much nickel as of manganese to produce the same result. The influence of nickel in retarding the transformation of austenite into the lower transition constituents is due to its lowering of the critical range of the steel, which is also well illustrated by Sauveur(1) (after Osmond) in his Fig. 284, reproduced here as Fig. 2. Scott(15) presents a diagram illustrating the effect of manganese on the Ac3 and Ar3 points which is strikingly similar to the diagram above referred to in Fig. 2 concerning the effect of nickel.

Jan 1, 1934

By W. F. Hosford, E. W. Kelley

By testing polycrystalline specimens from textured plates which had Previously been used to provide materials for growing single crystals, it has been possible to relate the plastic anisotropy of textured materials to the deformation behavior of single crystals. The deformation studies have been conducted at room temperature on textured polycrystalline magnesium and binary Mg-Th and Mg-Li alloys. Variously oriented specimens of the textured materials were deformed in plane-strain compression and in uniaxial tension and compression. The stress-strain curves are similar in their general jorm of anisotropy and stress levels to those obtained on single crystals of the same alloys. The degree of anisotropy is lower, however, in the polycrystalline materials and correlates with the intensity of the basal texture. Yield loci for the textured materials appear reasonable in terms of the deformation mechanisms, and deviate sharply from the form predicted by the Hill analysis for aniso-tropic material. A N earlier study1 of single crystals has shown that magnesium and magnesium alloys with thorium and with lithium deform at room temperature primarily by basal slip, {10i2) twinning, and (1011) banding. The (10i1) banding mode is a combination of {10ll) twinning followed by (1012) twinning and basal slip within the doubly twinned material.2, 3 Magnesium with lithium can also deform by {1010)(1210) prism slip.1'4'5 Still other deformation modes have been reported for magnesium6-11 but these are considered to play a minor role in room-temperature deformation. In a polycrystalline material, plastic deformation must occur in the individual grains through the operation of one or more of the various deformation modes. Because the critical shear stress for basal slip is very low compared to the activation stresses for the other deformation modes,' basal slip accounts for much of the deformation in the polycrystalline aggregate. However, since there are only two mutually independent basal slip systems, and because five independent systems must be active for an arbitrary shape change in any material,'' modes other than basal slip must account for some of the strain. The deformation of textured magnesium, like that of other hcp metals, must be controlled by the same mechanisms observed in single crystals. In strongly textured material, the form of the anisotropy should be similar to that of single crystals, and the degree of anisotropy should depend on the intensity of the texture. EXPERIMENTAL PROCEDURE The anisotropy of deformation was investigated through the use of plane-strain compression tests, as well as uniaxial tension and compression tests. Materials. Test specimens were cut from the three textured plates of magnesium which had previously been used to provide material for single crystals.' These plates, furnished by Dow Chemical Co., had been reduced about 80 pct during the process of being hot-rolled to their final 1/4-in. thicknesses. The plates had the three respective compositions, pure magnesium, Mg-0.5 wt pct Th (0.49 pct Th by spectro-graphic analysis), and Mg-4 wt pct Li (3.84 pct Li by chemical analysis). Impurities other than iron were less than 0.0005 pct Al, 0.01 pct Ca, 0.001 pct Cu, 0.0006 pct Mn, 0.001 pct Ni, 0.003 pct Pb, 0.001 pct Si, 0.001 pct Sn, and 0.01 pct Zn. Iron was 0.001 pct in the pure magnesium, 0.002 pct in the Mg-0.5 pct Th, and 0.014 pct in the Mg-4 pct Li. The textures of the three plates were determined by X-ray diffraction utilizing only the reflection technique out to an angle of 50 deg from the sheet normal. The resulting basal pole figures are presented in Figs. 1, 3, and 5. Grain sizes in the plates were ASTM number 4 in the pure magnesium and number 7 in each of the alloys. Plane-Strain Compression Tests. Plane-strain compression specimens approximately $ in. thick by 4 in. wide by $ in. long were prepared for each of the three compositions. These specimens were prepared in a manner similar to that used for the single-crystal specimens of the earlier study.' All polycrystalline specimens were stress-relieved at 500°F for hr as the final step in their preparation for testing. The testing procedure was identical to that used for the single crystals, involving compression in a channel and using 2-mil Teflon film as a lubricant. The specimens were tested in six orientations of interest, these being the six combinations of the rolling, transverse, and thickness directions of the material serving as loading, extension, and constraint directions in the plane-strain compression test. Each of the six orientations was assigned a two-letter identifying code. These are combinations of the letters (thickness direction), R (rolling direction), and T (transverse direction) with the first letter signifying the loading direction and the second letter the extension direction. For example, ZR specimens were compressed in the thickness direction while extension was permitted to operate in the rolling direction of the textured material. To facilitate comparison of the present work with that of the single-crystal study1 the orientations used for single crystals are given in Table I along with the polycrystalline orientations that most nearly correspond. To insure reproducibility, at least three duplicate

Jan 1, 1969

By Charles Meyer

The year 1955 was a busy one for mining geologists, for the expanding world-wide business activity kept the demand for mining products generally high, stimulating operators to develop local ore reserves and to expand their efforts to find new deposits. The uranium rush was still on, although probably past its maximum rate of climb. Prospecting was also stimulated by the increasing demand for rare metals, and this created new and fascinating targets for exploration. On the whole, it was a boom year when the prospector's chronic optimism found few repressions.

Feb 1, 1956

By E. M. Cox, T. Rosenqvist

IN a recent investigation, carried out at the Institute for the Study of Metals, the affinity of sul-phur for iron, copper, and manganese was studied over the temperature range 700" to 1300°C.' It was found that copper exhibits a rather high affinity for sulphur, especially at higher temperatures; and attention was called to the possibility that copper when present together with sulphur in liquid steel would tend to lower the chemical activity of sulphur and thus interfere with the desulphurization process. It was clear, however, that the data for the equilibrium between pure copper and pure copper sulphide (Cu2S) could not give any quantitative information about the effect of copper when dissolved in liquid steel. The present work is concerned with the activity of sulphur in the diluted range of the binary iron-sulphur system, and with the influence of small amounts of copper on this sulphur activity. This investigation is in principle based on the same method previously described for the binary metal-sulphur studies;1,2 namely, reaction with hydrogen to form hydrogen sulphide. The equilibrium ratio PH2s/Ph2 in the equilibrium gas mixture is, for a given temperature, directly proportional to the sulphur activity. The activity of sulphur in liquid iron has previously been studied by Chipman and Ta Li,3 White and Skelly,4 and recently by Sherman, Elvander, and Chipman.5 Morris and Williams6 have studied the effect of added silicon, and Kitchener, Bockris and Liberman,7 and recently Morris and Buehl,8 the effect of added carbon on the sulphur activity. In present day steelmaking processes the steel bath contains between 0.01 and 0.1 pct sulphur, and the copper content may be as high as 0.5 pct. The equi-librium gas ratio (H2S/H2) would, for such a low-sulphur content, be too low to be measured with the experimental technique we use. It has been shown by previous investigators that the H2S/H2 ratio is closely proportional to the sulphur content up to about 1 pct sulphur. The sulphur activity at very low-sulphur content can therefore be calculated by linear interpolation between 0 and 1 pct sulphur. In order to show the general trend with increasing sulphur content, the present work has been carried out to about 3.5 pct sulphur. As the effect of copper was assumed to be more a function of the Cu/S ratio than of the absolute copper content, the runs with copper were made for certain constant values for this ratio.

Jan 1, 1951

By H. D. Keiser

Minor industrial minerals included in this chapter are: the alum minerals, bromine, calcium chloride, epsomite and other natural magnesium salts, iodine, meerschaum, quartz, industrial crystals other than quartz, and nonfuel gases (air, helium, carbon dioxide). Alum Minerals The natural alums comprise a group of hydrated double sulfates, the most important of which are potash alum, KAI(S04)2.12H20, the "alum" of popular usage; ammonium alum, (NH4)AI(SO4)2, known mineralogically as tschermigite; and soda alum, NaAI(SO4)2.12H20. Kalinite, KAI(SO4)2.11H20, and mendozite, NaAl(SO4)2, 11H20, are fibrous monoclinic alums, distinct from the isometric species potash alum and soda alum.4 Alunite, KAI3(S04)2(OH)6, also known as alumstone or alum rock, has been used as a raw material in the manufacture of alum since early times. All the natural alums are highly soluble and occur as surface evaporation products in arid regions or in sheltered places. Potash alum, together with the other natural alums, commonly occurs as an efflorescence or crevice filling in argillaceous rocks and brown coals that contain disseminated pyrite or marcasite. The mineral is derived by the action of sulfuric acid, formed during the weathering of the sulfide, upon alkali-rich aluminum silicates. Ammonia alum is found chiefly in lignite or broad-coal beds and bituminous shales. Alunite is most commonly associated with acid volcanic rocks, where the rock has been largely altered and alunite formed owing to the presence of sulfuric acid solutions or vapors. Aluminum sulfate, which for most uses is the essential ingredient of alum, may be found in saline residues resulting from the evaporation of natural water and may be formed by the action of acid waters upon aluminous rocks. A deposit of natural potash alum occurs in an irregular network of veins associated with sulfur in rhyolite in Esmeralda County, Nevada, about 35 miles west of Tonopah and 10 miles north of Silver Peak. Alum was recovered at a plant operated on the property between 1920 and 1923 by crushing the ore to ¾ in., grinding to minus 80-mesh, and counter-current leaching; the resulting alum solution was then filtered and crystallized. Alunite was of much interest during World War I as a source of potash and during World War II as a source of alumina. The wellknown deposits at Tolfa, Italy, are veins in trachyte and have been the basis of alum manufacture there since the middle of the fifteenth century. Pure alunite is insoluble in water and in common acids, but if it is heated to 500°C it loses its water of hydration, and the residue consists largely of anhydrous potash alum, part of which is readily soluble in water or acids. If the heat is increased beyond 500°C, most of the sulfur combined with the alumina is released as oxides and the residue consists of potassium sulfate and alumina. Thus, either potash alum (and aluminum sulfate) or potassium sulfate and alumina may be made. In the

Jan 1, 1960

By Charles Smeal, Robert J. Schafer, Max Quantinetz

Normally metal powders cannot be ground to sub-micron sizes because of welding and agglomeration phenomena. Through the use of selected grinding aids and grinding fluids, nickel and other metal powders have been ball-milled as fine as 0.1 It was found that certain inorganic salts are more effective grinding aids for metal powders than conventionally used surfactants. METAL and alloy powders are used to produce reagents, pigments, coatings, solders, brazes, and parts for industry by powder metallurgy techniques. They are also combined with refractory compounds to produce cermets and dispersion-hardened products. One of the interests at the Lewis Research Center has been to explore the potentialities of the dispersion strengthening process. Since the work of Ir-mann, many investigators have shown that the strength of dispersion-hardened products may increase with decreasing interparticle spacing.24 One approach to achieving small interparticle spacing is to combine fine refractory compounds and metal powders, preferably below 1 in size. In attempting to obtain fine metal powders, it was found that until very recently the best that could be obtained from commercial suppliers, particularly of ductile metals, was about 1.0 . Interest was therefore developed in providing finer metal powders for dispersion-hardening studies. Information obtained from the literature, from others working in the field, and from prior experimental work performed at NASA, led to a consideration of ball-milling as a technique to produce the desired materials. Some of the variables associated with ball-milling are the size, material, and nature of construction of the grinding container; the nature and amount of the grinding material and material to be ground; and the nature and amount of the grinding liquid and grinding aid, if employed, and the grinding time. In all ball-milling, welding and agglomeration can oc- cur as well as grinding. Because of the tendency of ductile metals to weld together, they are difficult to grind.5 The ultimate particle size obtained on grinding is generally the one at which the rate of grinding becomes equal to the rate of welding. To help delay welding and thus obtain smaller particle sizes, grinding aids are often employed. The principal objective of this investigation was to produce submicron metal powders by ball-milling the powders with selected grinding aids and grinding fluids. A secondary objective has been to attempt to explain the variations observed in grinding behavior by considering possible grinding mechanisms and correlating various parameters with grinding effectiveness. Three groups of ball-milling experiments were run; one in which the grinding aid was varied, a second in which the grinding fluid was varied, and a third in which the material being ground was varied MATERIALS, APPARATUS, AND PROCEDURE In the first group of experiments in which the grinding aid was varied Inco Carbonyl Grade B nickel powder initially 2.5 (all sizes refer to average particle size as measured by Fisher Sub -sieve Sizer) was used as the material being ground and 200-proof ethyl-alcohol as the grinding fluid. Surfactants, representative of typical organic structures, were selected as grinding aids. Inorganic salts used as grinding aids were chosen on the basis of the size and valence of their ions. Water soluble salts were used in order to facilitate their removal from the slurry after grinding. In the second set of experiments, grinding of the 2.5- Ni powder was tried in four different grinding liquids; water, cyclohexane, n -heptane, and methy-lene chloride. In this study seven grinding aids selected from those tried in the first group of experiments were employed. In the third group of experiments 200-proof ethyl alcohol was again used as the grinding fluid to mill Cu, Cr, Fe, Ag, and Ni powders of various initial particle sizes' All mill charges contained 300 ml of grinding liquid and 3000 g of 1/2 in. stainless steel balls. When inorganic salts were used as the grinding aid, 70 g of salt and 210 g of metal powder were employed, and with surfactants 6 g of grinding aid and 300 g of

Jan 1, 1962

By A. Donald Kelmers, Forest G. Seeley, B. Zane Egan

INTRODUCTION Coal ash, presently the fifth most abundant of the solid minerals produced in the United States, is expected to become the fourth most abundant by the end of this decade (1). The production of fly ash from the combustion of pulverized coal amounted to a total of 44 million metric tons (Mt) in 1977 and is expected to Increase to 91 Mt by 1985. Coal ash, which results from the Inorganic clay and mineral content of the coal, contains several elements and thus can be considered as a mined and crushed mineral resource rather than a waste material Furthermore, potential problems associated with fly-ash disposal ponds and the leaching of potentially hazardous elements through groundwater infiltration and/or rainfall provide additional incentive for processing fly ash for environ- mental control as well as for the recovery of certain metal values. Fly ash could provide an abundant domestic source of aluminum and several other metals Aluminum is now recovered from bauxite, and over 90% of this ore is imported since domestic sources are limited and cannot meet the U.S. demand There is a close relationship between the aluminum content of fly ash and the domestic consumption of this metal (Table 1).

Jan 1, 1981

By C. Schlumberger

LAST year the authors presented a paper that discussed the various electrical measurements they perform in drill holes, which they name "electrical coring."' The object of the present paper is to give a brief account of the points of scientific interest that have been elucidated by further field work and laboratory research, as well as the economic results that have been attained recently. The practical examples given in this paper are drawn, for the most part, from the field work performed in Russian oil fields during the years 1931 and 1932. This is due to the fact that, thanks to the comprehensive cooperation of the Russian geologists and scientists, the authors are allowed to make public a large amount of recent information. In other countries in which the authors are engaged in similar work, the competi-tion between private companies makes it imperative, for a considerable lapse of time, to avoid publication of the results obtained. The following points will be discussed successively, under sepa-rate headings: 1. Electrochemical phenomena in drill holes. 2. Stratigraphic correlations and tectonic studies. 3. Relations between the productivity of oil horizons and their electrical resistivity. 4. Location of coal seams. 5. Summary and conclusions.

Jan 1, 1933

By John Birkinbine

Modern advances in practically all lines of industrial develo1)ment have occurred in such rapid succession, and have been accepted so readily as accomplished facts, that a retrospect surprises us, by showing how comparatively few of the acknowledged factors of improved conditions may be considered as old. While these advances have not been confined to any country, they have been more pronounced in some than in others, and nowhere more so than in the United States, the population of which, having multiplied nearly three-fold between 1870 and 1910, demanded a proportionately greater increase in materials, supplies, and manufactured products. It therefore appears desirable to discuss mainly conditions in the United States, as concrete evidence of industrial progress throughout the world. Looking backward for but three generations, me mar trace the introduction and developmerit of canal- and steamboat-narigation ; railroad-transportation; artificial illumination beyond that f'urnished by candles and animal-oils; quick communication by mail, and subsequently by telegraph or telephone; the manufacture of iron, beyond forms of small dimensions; the production and utilization of steel in large quantities; the economic use of mineral fuel, oil and gas, etc. The practical coincidence of the fortieth anniversary and the 100th technical meeting of the American Institute of Mining Engineers, offers temptation to recall and compare the conditions of milling and metallurgy in or about the years 1871 .and 1911. A complete résumé would cover phenomenal changes in mining-methods and equipment by which the output of individual exploitations has grown from scores to hundreds and even thousands of units in equal time-intervals. Extension of operations in depth and area, demanding machinery of great power and efficiency, high percentage of extraction, utilization of what

Jan 1, 1912

Reginald S. Dean (Manganese Extraction by Carbamate Solutions and the Chemistry of New Manganese-Ammonia Complexes, P. 55) was born in Rolla, Mo. and attended the Missouri School of Mines. Mr. Dean has worked as metallurgist with Western Electric Co. from 1920 to 1929 and with U. S. Bureau of Mines from 1929 to 1946 as chief metallurgist and assistant director, and has been a metallurgical consultant in Washington, D. C. since 1946. An AIME member, Mr. Dean has presented at least 50 papers before the society. Mr. Dean is a member of American Society of Metals, American Chemical Society and Electrochemical Society. C. O. Dale (Illinois Operations of the Eagle Picher Mining and Smelting Co., co-author with W. J. Rundel, P. 72) was born in Twin Bridges, Mont. and attended Montana School of Mines and received his B.S. in mining engineering in 1944. Mr. Dale was with U. S. Navy Air Corps. as an electronics technician and worked as an engineer with C. O. Dale & Sons, Anaconda Copper Mining Co. and with Eagle Picher Mining & Smelting Co. At present he is Wisconsin manager of Eagle Picher Mining & Smelting Co. The application of machinery to mining is of special interest to Mr. Dale. A member of AIME, Mr. Dale is on the Room and Pillar or Stope and Pillar Committee of Mining Subdivision for 1951 to 1952. Mr. Dale is a member of Montana Society of Engineers and Lions Club. Golfing, fishing and wood working are his hobbies.

Jan 1, 1952

By Richard D. Snouffer

Prime topics of conversation these days are the new concepts of rail haulage for bulk items such as iron ore, potash and coal. We have heard such ideas as the "integral train" and the "unit train" discussed frequently during the past two years at various AIME meetings, and progress reports have kept up a steady appearance in the technical press and in local newspapers. While no railroad has a complete "unit train" in service at this moment, one has 50 fast-discharge cars under construction and the Pennsylvania Railroad has experimented with radio-controlled motive power distributed at intervals throughout the train. To a great extent, however, the promise for greater efficiency and lower costs held out to industry by these new haulage methods is dependent not on greater speed or larger cars or more dedicated equipment alone but, rather, on the utilization of modern practices in the loading and unloading of rail cars. It is the purpose here to examine these two key steps and the up-to-date procedures and equipment they entail.

Jan 7, 1963

By G. C. Broadhead

THE lead district of Southeast Missouri covers an area of over 3000 square miles, including Maries County on the west, Jefferson on the east, Franklin on the north, and part of Madison on the south, or parts of ten counties. A general section of the rocks of the southeast part of this region would be about as follows, numbering from the top 1. Sandstone (the second of Missouri geologists), - 20 feet. 2. Cbert beds-beds of passage below, - 125 feet 3. Magnesian limestone, chert, and quartzite, - 100 to 300 feet 4. Lower magnesian limestone, - 100 to 150 feet 5. Gritstone and lingula beds, - 50 feet 6. Ozark marble beds, - 5 to 20 feet 7. Sandstone and conglomerate, - 5 to 90 feet 8. Porphyry, Archaean. 9. Granite, The thickness is approximate, for it is not possible to obtain the correct thickness of the various beds. No. 1 may be seen as de¬tached outliers or loose masses of a hard sandstone or quartzite, and is found on the hilltops in the southern part of Madison County, in like topographical position in Reynolds County and the western part of Washington County. No. 2 consists of alternations of chert, clay, and quartzite. It is the formation which contains most of the limonite deposits of Central and Southern Missouri. In Reynolds County shafts have pene¬trated it 75 feet. Outcrops there and in Madison would indicate it to be at least 125 feet thick. Fossils obtained in various places prove it clearly to be of the age of the calciferous sandrock of the New York system, and Nos. 1 and 2 may also be referred to the age of the second sandstone of Missouri. No. 3 consists chiefly of thick beds of ash, drab and flesh-colored magnesian limestone, both coarse and fine-grained. These beds, where they occur, in Washington, Jefferson, and the southern part of Madison Counties, contain a good deal of quartz in drusy cavities. In Washington County the limestones are beautifully ramified by a system of connected drusy cavities generally lined with minute quartz crystals arranged in botryoidal and mammillary forms, and called u mineral blossom " by the miners. This is the lead-bearing rock of Washington County, but in the southern part of Madison it does not appear to be galeniferous. It is also undoubtedly the equivalent of

Jan 1, 1877

By Edward Keller

ALTHOUGH the subject matter contained in this paper is presented under a new title, its writing was induced by the work of S. Skowronski and K. W. McComas.1 A discussion of the latter is here combined with the presentation of new and independent data. The physical constants quoted by the authors of that paper, such as melting and boiling points, as also the chemical reactions of the substances involved, are so well established that the numerous confirmatory experiments and their application to metallurgical conditions leave little or no room for criticisms. On the contrary, they will greatly aid to dispel any lingering skepticism as to possible considerable losses of copper accruing when the metal is melted in the presence of its own and, probably, other chlorides and when no provision is made for the recovery of volatile products. Exception may be taken, to some degree, to that part of the work under the caption Melting Drillings of Copper Mixed With Sodium Chloride. These experiments should have been extended in order to make the implied reactions clear and the results convincing. The latter are stated to be, "that when sodium chloride is present above certain minimum quantity relative to copper some of it is found to volatilize in the melt while another part reacts with the metallic copper to produce the volatile cuprous chloride, and that When smaller quantities of sodium chloride are present the reaction is complete and all chlorine is found to have volatilized as cuprous chloride." Metallic copper and sodium chloride are mentioned as the sole reagents in this chemical process, acting, according to the authors, in a neutral atmosphere of carbon dioxide. The chemist, quite naturally, will inquire into the formula according to which that reaction takes place and find that it would present itself as follows: 2Cu + 2NaC1 = 2Na + Cu2Cl2 It would appear that the truth of this formula will be challenged and a more rational explanation of the reaction sought. Apparently, carbon dioxide is neutral relative to metallic copper in its molten state; whether it remains neutral in the presence of sodium chloride is quite another question. Does it not at that high temperature become an oxidizer and do not the conditions of the reaction change to those expressed in the following formula? 2Cu + 2NaCl + 2002 = Na2CO3 + CO + Cu2Cl2

Jan 9, 1919

By G. C. Broadhead

The lead district of Southeast Missouri covers an area of over 3000 square miles, including Maries County on the west, Jefferson on the east, Franklin on the north, and part of Madison on the south, or parts of ten counties. A general section of the rocks of the southeast part of this region would be about as follows, numbering from the top: 1. Sandstone (the second of Missouri geologists),.... 20 feet. 2. Chert beds—beds of passage below,...... 126 " 3. Magnesian limestone, chert, and quartzite,. .. 100 to 300 " 4. Lower magnesian limestone,......100 to 150 " 5. Gritstone and lingula beds,....... 50 " 6. Ozark marble beds,........5 to 20 " 7. Sandstone and conglomerate,. .. .. 5 to 90 " 8. Porphyry, Archæan 9. Granite, The thickness is approximate, for it is not possible to obtain the correct thickness of the various beds. No. 1 may be seen as detached outliers or loose masses of a hard sandstone or quartzite, and is found on the hilltops in the southern part of Madison County, in like topographical position in Reynolds County and the western part of Washington County. No. 2 consists of alternations of chert, clay, and quartzite. It is the formation which contains most of the limonite deposits of Central and Southern Missouri. In Reynolds County shafts have penetrated it 75 feet. Outcrops there and in Madison would indicate it to be at least 125 feet thick. Fossils obtained in various places prove it clearly to be of the age of the calciferous saudrock of the New York system, and Nos. 1 and 2 may also be referred to the age of the second sandstone of Missouri. No. 3 consists chiefly of thick beds of ash, drab and flesh-colored magnesian limestone, both coarse and fine-grained. These beds, where they occur, in Washington, Jefferson, and the southern part of Madison Counties, contain a good deal of quartz in drusy cavities. In Washington County the limestones are beautifully ramified by a system of connected drusy cavities generally lined with minute quartz crystals arranged in botryoidal and mammillary forms, and called " mineral blossom " by the miners. This is the lead-bearing rock of Washington County, but in the southern part of Madison it does not appear to be galeniferous. It is also undoubtedly the equivalent of

By George B. Holderer

The relation between man-hours of labor and production may be correlated for any industry, and already it has been widely used in piecework studies. It is not in general use as yet for recording labor efficiency of an enterprise or an industry. An exception to this is the Cement Institute, which tabulates the man-hours used in each operation and thus gets the total man-hours per barrel of cement. The writer knows of one steel company that keeps a complete record of man-hours for every operation from mining the ore to finishing the product. No doubt many others find the information useful, and such a study could be of value to the mineral industries.

Jan 1, 1937

By P. F. Richardson, J. L. Perisho, W. J. Roe

Handling and transport of coal during the winter months can be a severe problem. The inability to unload frozen coal from rail cars produces serious economic and logistic problems due to transportation delays, rail car shortages, and demurrage on the rail cars. One method of dealing with the problem of unloading frozen coal has been to spray freeze conditioning agents onto the coal before it is loaded into rail cars. Both water soluble and oil based formulations have been used as freeze conditioning agents. The water soluble treatments generally contain a polyhydroxy alcohol, such as ethylene glycol, or salts of alkaline earth metals, such as magnesium chloride and calcium chloride, as freeze point depressants. The oil based treatments consist principally of hydrocarbons, such as No. 2 oil or diesel fuel. The authors' tests have shown significant differences in the effectiveness of these freeze conditioning agents, depending on the particular coal substrate being treated. These differences correlate with the coal porosity and inherent moisture of the substrate. In general, the greater the porosity of the coal, the smaller the effect of the freeze conditioning agents. Coal porosity has a greater impact on water soluble freeze conditioning agents than oil based products. The authors investigated the pore structure of a variety of coals using mercury intrusion. Findings were related to the effectiveness of different freeze conditioning agents as measured by unconfined compression strength tests. In general, coals with a large number of very small pores (between 0.05 µm and 0.03 µm) do not respond as well to freeze conditioning chemicals.

Jan 1, 1986

By James M. Townsend

INTRODUCTION The first stage in planning any mining venture is to determine whether the reserves are of sufficient quantity and quality to warrant commencement of mining activities. In addition to total reserve values a modern mining operation requires information on possible support problems, various pillar sizes, and an estimate on recoverable reserves. To achieve this goal in U. S. coal mines, up-to-date computer methods have been applied to existing ground control technology to provide the mining engineer with a reasonably accurate method of determining such figures. The purpose of this paper is to present a mine planning suite comprised of three computer programs, CONTUR, RESERV-COAL and RAMPLAN, created to accomplish this task. These programs were developed at VPI under the sponsorship of the Office of Coal Research (now Energy Research and Development Administration), and are currently available to the mining industry. A basic assumption in the construction of the CONTUR program is that a coal seam is variable in nature. The data available to the mining engineer comes from randomly spaced points, namely boreholes and sampling points, on outcrops or in adjacent mines. These randomly spaced data points are used in the CONTUR program to estimate numerical values at evenly spaced grid points and to provide approximate contour plans. Given the necessary gridded data, RESERV-COAL calculates raw and clean coal tonnages and then provides breakdown on the quantity of coal within specified ranges of ash, sulfur, BTU and reject. RAMPLAN (Rock Mechanics Applied to Mine Planning) also uses gridded data to calculate mining dimensions and estimate recoverable reserves, thereby

Jan 1, 1977

By Donald W. Barnett

U.S. environmentalists have tended to oppose all new energy developments. Their efforts may be counterproductive because opposition to, say, offshore oil directly leads to the continued use of other energy sources that may have a higher social cost. Rather than attempting to eliminate all pollution from energy production, which would be prohibitively expensive, one should minimize the social cost of energy production for the given demand. Linear programming is used to rank various oils (California State and O.C.S., Gulf of Alaska, Prudhoe Bay, Athabasca tar sands, oil shale and certain foreign crudes) in terms of their social desirability. The objective is to minimize the cost of supplying the California market, subject to resource, sulphur and oil spill constraints. Social desirability is indicated by the inclusion of the oil in the optimal solution and the size of the associated shadow price. the larger the shadow price, the greater the benefits of increased production. The more negative, the greater the cost associated with forcing consumption of that fuel. The environmental shadow prices indicate the size of the trade-off between a particular environmental standard and minimum cost. The trade-offs can be surprisingly large. any reasonable spill standard can be achieved by changing the development pattern. Generally, the further offshore, the smaller is the environmental degradation, but the more expensive is the oil. Foreign oils can be economically and environmentally inferior to domestic oils. Crude from the California O.C.S., San Joaquin Valley end Prudhoe Bay appears a valuable resource, while the Gulf of Alaska, synthetic and foreign crudes appear marginal to submarginal.

Jan 1, 1977

By J. J. Egan, A. B. Kinzel, W. Crafts

Advances in the production of quality steel have emphasized the need for greater knowledge of the amount and distribution of oxygen in the steel. Control of inclusion content and quality is largely dependent on such knowledge. While many analytical methods have been devised for the accomplishment of this end, few are without serious limitations in accuracy, convenience, or skill required in application. Usually at least two methods are necessary to determine total oxygen and constituent oxides. Because of the great importance of this problem and the specific interest in the application of such methods of analysis, the various procedures were carefully reviewed at the Union Carbide and Carbon Research Laboratories, with the view of developing a method free from the limitations mentioned above. Intensive experimentation finally led to an improved iodine extraction analysis described by Cunningham and Price.1 After this had been thoroughly checked from the standpoint of the analytical chemist, it was rechecked from that of the metallurgist. This involved preparation of a number of small heats of varying composition with determination of total oxygen in the molten metal by the alumina method2 and an analysis of the solidified material without the aluminum addition by means of iodine extraction; the oxides of iron, manganese, silicon and aluminum also being determined by the iodine analysis. The report of this work constitutes the subject of this paper. The Iodine Method Fundamentally the iodine method is well established. It is based on the procedure first described by Eggertz3 and depends upon the fact that iron, manganese, silicon and aluminum, as well as the metallic constituents of the pertinent sulfides, carbides and nitrides of these metals

Jan 1, 1933

By D. Turnbull, A. M. Turkalo

It is well known that if copper that has been severely cold-worked by rolling (70-98 pct) is heated to high temperatures a small number of large grains are formed at the expense of the fine grained structure that appears upon primary recrystallization. Dahl and Pawlek,' Cook and Mac-Quarie,2 Ward,3 and Boas and Bowles4 have studied this phenomenon in copper. It has been reported as taking place with measurable velocities in the temperature range 700-1080". Boas and Bowles have reported that the time necessary for the transformation is of the order of days at 700°C. According to Ward3 the number of secondary grains which appear in OFHC copper decrease with increasing perfection of cubical alignment after primary recrystallization; also the perfection of cubical alignment increases with decreasing grain size prior to the final reduction. In this investigation two heats, A and B, of especially high purity copper (99.999 pct) supplied by the American Smelting and Refining Co., were used. The behavior of samples prepared from the two heats was qualitatively very similar providing that the grain sizes established prior to the final reduction were about the same. We observed that in specimens prepared from bars which were relatively coarse grained prior to final reduction secondary recrystallization took place at a rapid rate at temperatures as low as 500°C. This is about 200-300°C lower than the temperature necessary to obtain fairly rapid transformation in OFHC copper. A 0.22 in. thick rectangular bar of lot B was cold-reduced 60 pct by straight rolling and given a penultimate annealing treatment at 250°C. Following this it was cold-reduced 90 pct and heated to various temperatures in the range 450-1040°C. The specimens were about 8 mils thick

Jan 1, 1950