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By L. A. Neumeier

A refinement of the tungsten-cobalt phase diagram is presented for compositions to 85 at. pct cobalt and for temperatures to the solidus. Preparation of alloys by powder metallurgy methods is described, and the results of studies made by a combination of techniques involving microscopy, X-ray diffraction, thermal analysis, and dilatometry are discussed. The existence of u-W6Co7 is confirmed (rhombohedral D85 structure). The W6Co7 phase forms periectically at 1,685'115° C by reaction of liquid with primary W; the peritectic melt is at 71 at. pct cobalt. The homogeneity range of u-W6Co7 extends to both sides of the ideal stoichiometric ratio, through a compositional range of about 5 at. pct. The compositional limits for u-W6Co7 vary slightly below 1,471°±5° C, the temperature of the eutectic reaction forming u-W6Co7 plus a. The eutectic composition is at 79 at, pct cobalt. The existence of WCo3 is confirmed (hexagonal D019 structure). WCo3 forms peritectoidally at 1,093°±5° C by reaction between a and u-W6Co7 and exists over a narrow homogeneity range of 0.5 to 0.6 at. pct. The solid solubility of cobalt in tungsten is low (maximum 0,9 at, pct cobalt) and results in contraction of the tungsten lattice. Tungsten is extensively soluble in a-Co at higher temperatures; the a-Co lattice is expanded by the presence of tungsten in solid solution. There was no indication of the formation of a o-phase nor of any intermediate phases other than WeCo7 and WCo3. The WeCo7 and WCo3 phases are compared with similar phases in other systems.

Jan 1, 1967

By G. L. Gates

The Bureau of Mines in cooperation with the City of Long Beach) Calif.) studied some physical factors effecting the deposition of barium sulfate scale in oil-well rotary pumps. Freshly formed barium sulfate was obtained by combining sulfate in sea water with barium from a barium chloride solution. The rate of scale deposition was measured quantitatively by weighing the pump impellers and diffusers. The results of the tests showed that coating the impellers with plastic significantly reduced the rate of barium sulfate deposition.

Jan 1, 1967

By Jr. Fish

As a part of a study of iron are resources in the Appalachians, 9 diamond drill holes aggregating 1,580.7 feet were drilled in a portion of the Butt Mountain area of northeastern Giles County, Virginia. Three hematitic sand-stone beds were intersected in the Clinton formation but only one was consistent in thickness and grade in all 9 drill holes. This bed averages 18.9 percent iron over an average thickness of 24 feet. The drill cores were logged and chemical analyses were made on 161 individual samples and 22 composite samples. Beneficiation studies were made of three composite hematitic sandstone samples each representing a separate bed containing 14.6, 19.8 and 20.0 per-cent iron. Major mineral constituents of the samples were hematite, quartz, and sericite.

Jan 1, 1967

By R. L. Hopkins

Some typical thiacyclopentanes and thiacyclohexanes were synthesized to provide reference compounds needed for the identification of sulfur compounds in crude oils. Two general methods of synthesis were employed: (1) cleavage of 2-alkyltetrahydropyrans with hydrogen bromide followed by the reaction of the resulting dibromoalkanes with sodium sulfide and (2) the catlyzed reaction of cyclic ethers or 1)4-or 1)5-alkanediols with hydrogen sulfide. Both methods produced mixtures of 2-alkylthiacyclopentanes and 2-alkylthiacyclohexanes with 2-alkyltetrahydropyran as the starting material. The structures of the reaction products were established by analysis for sulfur; desulfurization; gas-liquid chromatography (GLC); mass, infrared, and nuclear magnetic resonance (NMR) spectra; and an alternate synthesis. The synthesis of the cyclic sulfides contributed substantially to the identification of 10 members of this class of sulfur compounds in crude oil.

Jan 1, 1967

By R. T. Sorensen

Bench-scale and continuous testing were performed to adapt the anionic process for flotation of calcium activated silica to the fine-grained hematitic-goethitic jaspers from the Marquette range, Michigan. These ores typically contain about 35 percent Fe and require grinding to about 80 to 100 percent minus 400 mesh to insure an adequate liberation of gangue from the iron oxides. A method for removal of troublesome slime fractions without excessive iron loss, by first dispersing the quartz and then selectively flocculating the iron oxides, was evolved in the laboratory and successfully accommodated to pilot plant practice. The efficiency of the flotation process was improved with respect to both reagent usage and concentrate grade and recovery by using the selective flocculation-desliming technique as a pretreatment. The benefits of the combined desliming-flotation procedure were most evident in pilot plant processing. The best tests on two ores yielded recoveries of about 84 percent in concentrates containing 65.1 percent Fe and 4.8 percent SiO2 and 66.2 percent Fe and 3.9 percent SiO2, respectively. These results are in comparison to recoveries about 10 percent lower than the above to concentrates containing 63.9 percent Fe and 6.6 percent SiO2 in the one instance, and 63.6 percent Fe and 7.2 percent SiO2 in the other, obtained by flotation without the prior desliming treatment.

Jan 1, 1967

By Ernest A. Curth

The Bureau of Mines studied pressure changes in coal pillars by using encapsulated hydraulic pressure cells to measure relative changes in stress developed during mining. The data indicate that (1) abutment stresses were detected when the pillar line is within 42 to 100 feet, (2) vertical pressure increases as coal is mined in the pillars, (3) at first pressure is higher at the edge of the pillar than in the core, but as mining progresses, the higher pressure is measured in the core of the stump, and (4) in the two instances where lateral pressures were measured, they remained lower than the vertical pressures during pillar extraction. The data also indicate that the mean vertical pressure increase, 6P, in a pillar is roughly related to the percent of pillar extracted, A, by the empirical parabolic equation

Jan 1, 1967

By Maurice Deul

A special short-term research project was initiated to develop plant design parameters for treating mine waters to yield an effluent acceptable for discharge into streams and a sludge amenable to effective and economic disposal. Neutralization was investigated to provide simple and direct treatment of ferruginous acid waters using lime; coarse limestone, and limestone followed by lime. Limestone treatment was accomplished using a small cement mixer as a simple reactor to provide abrasive agitation of limestone and mine water. Results from tests with nine mine waters encompassing a wide range of iron and acid concentrations showed that coarse limestone, one of the cheapest neutralizing agents known, is potentially useful for treating mine water discharges. However, process variables must be defined more completely before the practical applications and limitations of the process can be fully established. In all the tests a pH of >7.2 was obtained ultimately with limestone. Reaction time to reduce the iron content below 7 ppm in the water was dependent on the original ferrous iron concentration. For waters with high ferrous iron content, treatment with limestone followed by lime rapidly produced an acceptable treated water, Sludges with good settling and handling characteristics resulted when limestone was used for neutralization either alone or with subsequent treatment. Reaction rates are expressed graphically as pH change and iron depletion curves; characteristic solids settling curves are shown. The temperature dependency of ferrous iron oxidation was verified.

Jan 1, 1967

By W. S. Sanner

Seven samples were analyzed from the major reserves of the Bottom Red Ash bed, Northern anthracite field. The data show variations in thickness and geo-logic structure and in the amount of coal that can be recovered. Recovery of market-grade (less than 17 percent ash) coal is high for all samples, ranging from 76 tp 95 percent in the 3-1/4-by 9/16-inch sizes. The occurrence of coal containing less than 5 percent ash varies from 19.5 to as much as 57.5 percent. Crushing the coarse sizes to minus 9/16 inch increased recovery of market-grade coal in six of seven bed samples. Crushing released sufficient impurities to cause substantial increases in yield of coal containing less than 5 percent ash for all samples. Analyses of the float coal indicate that the quality of coal is comparable for all samples.

Jan 1, 1967

By William R. Hardwick

Present information indicates that a copper deposit can be safely fractured with a nuclear explosive and the copper successfully recovered by the in-situ leaching method. The process is not yet at the stage where it can be presented t ) the mining industry as a technique proven in all its aspects, but it is a method with high success potential. Unknown factors must be evaluated by a full-scale test before the economics or the extent of the use of the method by the mining industry can be predicted. Preliminary calculations indicate that the cost of fracturing a copper deposit nuclear explosives may range from l.8 to 55.2 cents per ton or in some case: less than a cent per pound of recoverable copper. Copper may be recovered at less cost than by conventional methods. Deposits with 4 pounds of recoverable copper may be economic and production from a deposit may begin in less than half the time required for conventional methods.

Jan 1, 1967

By Robert W. Ageton

Optimal planning for mining the deep, lead-zinc-silver deposits of the Coeur d'Alene mining district, Shoshone County, Idaho, could be facilitated by a knowledge of the magnitude and direction of the pressure acting in the virgin rock. The distribution of primary stresses should be considered in order to prevent possibly destructive mining-induced stress concentrations. This particular investigation was concerned with determining stress in a zone 4,000 feet below the surface and known to be ender stress concentrations due to mining operations. Disking of the stress-relief cores obtained in a vertical down hole permitted qualitative evaluation from visual observations; the results indicate that a high lateral stress existed at the time the measurements were made. Stress-ellipsoid determinations gave a compressive principal stress of -13,000 psi oriented about N 45° W and nearly horizontal, a compressive principal stress of -11,000 psi oriented about S 45° W and abut 60° off the vertical pointing away from the vein, and a compressive principal stress -5 -7,000 psi oriented N 45° E and about 60° off the vertical, pointing toward the vein. Subsequent to the overcoring stress-relief drilling, a rock burst occurred about 100 feet northwest of the test site.

Jan 1, 1967

By A. W. Deurbrouck

This Bureau of Mines report describes the preparation characteristics of the significant coalbeds from which samples could be obtained in Upshur County, W. Va. One of the 14 samples collected was of metallurgical quality as received, 6 could be sufficiently upgraded to provide acceptable products, and 7 could not be upgraded to metallurgical quality because of their high sulfur contents.

Jan 1, 1967

By Bernard Porter

The rate of the heterogeneous reaction between reactor-grade yttrium and lithium fluoride in lithium fluoride-yttrium fluoride mixtures was measured using a quartz spring balance. At 950° C the magnitude of the rate of reaction is 10-5 grams of yttrium/cm2-sec. The heat of activation for the reaction is 38.3 kilocalories per mole of LiF. A surface-controlled mechanism is proposed in which LiF is adsorbed on the yttrium metal surface. An activated complex is formed when additional LiF reacts with the adsorbed LiF-metal site. The activated complex then decomposes to the products) which are lithium metal and YF3. The importance of the reaction in the electrowinning of yttrium metal from fluoride electrolytes is discussed.

Jan 1, 1967

By Robert H. Merrill

This Bureau of Mines report summarizes the design and tests of a gage that will simultaneously measure the deformation of a borehole along three diameters 60 degrees apart; the measurements are in a single plane normal to the axis of the borehole. The inherent errors in measurement are considered together with the problems associated with the use of the gage in the relatively severe environments in and around mine openings. These problems were treated in the design and tests of the gage and the results establish that the gage can be used to satisfactorily is determine estimates of the stresses in rock.

Jan 1, 1967

By Stephen D. Cramer

The objective of the present studies was to develop thick adherent and coherent coatings of platinum and palladium on refractory metals and other substrates of industrial and engineering importance. Existing platinum and palladium electrolytes were modified to make them suitable for the electrodeposition of thick deposits. The optimum operating conditions for these electrolytes were established. Pretreatment procedures for columbium, copper, graphite, molybdenum, nickel, stainless steel, tantalum, titanium, tungsten, vanadium, and zirconium substrates were studied. New pretreatment procedures for columbium, molybdenum, stainless steel, tantalum, tungsten, and nickel were developed. The internal stress and hardness of selected electrodeposits were measured. The effects of heat treatment upon the properties of electrodeposits were studied.

Jan 1, 1967

By Webster S. Anderson

The design, development, and testing of hydraulic props to provide a lightweight, high strength, recoverable unit is described. Modifications in design incorporating threaded components resulted in the development of a lightweight hydraulic prop fabricated from aluminum alloy tubing. This new design facilitates interchange and replacement of component parts, and the physical properties of the material are not changed as they are when welding is required. The new prop is 65,000 pounds and has a maximum load capacity of a lower weight-to-load capacity ratio than the hydraulic props now available.

Jan 1, 1967

By John Ward Smith

Oil-yield data are presented for core samples from Colorado Corehole No.1, drilled by the Bureau of Mines and the Atomic Energy Commission in a previously untested oil-shale area near the northern edge of Colorado's Piceance Creek Basin. Continuous oil shale 2068 feet thick, averaging 18.41 gallons of oil per ton of shale and representing 1.8 billion barrels of oil per square mile, occurs at the core site.

Jan 1, 1968

By M. O. Magnuson

As part of an experiment in the restoration of lands strip-mined for coal, revegetation studies were conducted at three backfilled strip-mine sites in north-central Pennsylvania. The sites were subdivided into plots that were given varying amounts of lime and fertilizer. In tests conducted cooperatively with State and Federal agronomy experts, the plots were then planted with a variety of trees, shrubs, and grass-legume mixtures. Initial tree and shrub survival was not appreciably affected by lime and fertilizer applications where the spoil pH was above 4.5. Of 14 species of trees and shrubs tested, Norway spruce, black locust, Japanese larch, pitch pine, and white pine were the hardiest. The ground-cover percentage of grass-legume mixtures in the second growing season was substantially increased by using lime and fertilizer. Mixtures comprised partly of fescue were the most satisfactory.

Jan 1, 1968

By T. N. Rushton

Rate minima are encountered in the reduction of magnetite with hydrogen. In a certain temperature zone, the reaction rate decreases with rise in temperature. This is inexplicable by classical kinetic theories; neither is a transition in reduction mechanism suitable for interpreting the observed behavior, This anomaly can be fully explained by hypothesizing two species of chemisorbed hydrogen with different adsorption coefficients and activation energies for adsorption. Competition between two energetic states of adsorption occurs with temperature rise, with the low energy state predominating below the anomalous temperature zone and the high energy state above it. The presence of two possible adsorption sites appears to be characteristic for oxidic adsorbents.

Jan 1, 1968

By R. S. Fowkes

Jetstream pressure distributions and coal cutting rates were determined for a number of nozzles and under different operating conditions. The jetstrearn pressure distribution data were fitted to an assumed curvilinear equation by the utilization of a numerical least-squares technique with the aid of a digital computer. Subsequent manipulation of the approximation equation showed that the total force of the jetstream, rather than its maximum pressure or total kinetic energy per unit Lime, was the most significant quantity affecting the coal cutting rate. A shorter method for assessing the ability of a nozzle to cut coal was found.

Jan 1, 1968

By R. J. Leary

This investigation was conducted to determine the effects of various rare-earth metal addition practices upon the macrostructure and the pattern of sulfur distribution in steel ingots. Heats of plain carbon steel were melted in a 1-ton, basic electric-arc furnace. Melts were treated with mixtures of rare-earth silicides, aluminum, and cryolite either in the furnace before tap or in the ladle after tap to determine the effects of this form of rare-earth treatment upon ingot macrostructure. Steels thus treated with rare earths in the furnace were characteristically free of the gross subsurface nonmetallics which typically result from conventional rare-earth treatments. Steel treated in the ladle showed only a few such nonmetallics, and practical techniques were developed for eliminating most of these. Results showed that furnace deoxidation was controlled by the concentration ratio of rare earths: aluminum. During casting, deoxidation was controlled by the concentration of rare earths. Oxygen contents equivalent to vacuum ladle degassing resulted from air-melt furnace treatments with the rare-earth mixtures described. Rare earths in steel inhibited the onset of equiaxed grain formation during ingot freezing, and also virtually prevented interdendritic segregation of sulfides.

Jan 1, 1968