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By E. R. Stover, J. Wulff

A tentative 870°C isothermal section, the solidus equilibria, and the solubility of Tic and graphite in the nickel solid solution have been determined with arc-cast specimens. Each of the Ni-Ti intermetallics forms two-phase fields with Tic; only Ti,Ni has a measurable solubility for carbon. A quasi-binary eutectic exists between Tic: and a titanium-rich nickel solid solution; ternary eutectics occur on either side, with TiNis or with graphite. Graphite is in equilibrium with a nickel solid solution containing a ratio of Ti/C which increases below the solidus. DURING the past decade, titanium-carbide cermets containing nickel or cobalt alloy binders have been widely studied for high-temperature and wear-resistant applications. Recent work has emphasized control of the carbide grain size and distribution2's and the thermal exparision match between the phases/ The present study was initiated to determine the phase compositions during the sintering or infiltration process, and during subsequent heating. Although the effects of additives and impurities in commercial compositions are important, it was necessary to consider first the pure ternary, Ni-Ti-C. Emphasis was placed on the nickel corner, since the nickel solid solution is the continuous phase in compositions having highest strength. Early metallographic work by Zarubin and Molkov- showed that solid solubility at either end of the section Ni-Tic is small. Edwards and Raine reported that nickel dissolves between 3 and 5 wt pct Tic at 1250° C, on the basis of microstructures of annealed, vacuum-melted powder mixtures. Although the solubility of nickel in Tic has not been measured, Tic formed by the menstruum process in liuid-iron solution contains as little as 0.06 wt pct Fe. BINARY SYSTEMS The most recent determinations of the three binary systems are summarized in Fig. 1. Titanium carbide (6) is predominant among the binary phases, and it melts above the boiling point of nickel. The Ni-C binary is based on separate liquid solubility' ) and solid solubilitylo measurements. The eutectic temperature, 1328OC, is taken from the solidus determination described below. However thermal analysis data by Morrogh and williams also show eutectic arrests in this vicinity in the absence of supercooling. The Ni-Ti binary is taken from the work of Poole

Jan 1, 1960

By Albert Sauveur

Some writers believe that when austenite transforms completely into pearlite on slow cooling through the thermal critical range, such transformation does not imply the formation of any of the so-called transition constituents: martensite, troostite and sorbite. Might it not be claimed with as much justification that when water freezes it does so suddenly, solid ice being obtained without passing through the intermediate stages of ice and water? Obviously, regardless of the speed of solidification, this would be erroneous. Before reaching the completed solid condition, this must of necessity pass through an unbroken series of stages when the system consists of mixtures of water and of ice, the former decreasing and the latter increasing in amount. Are not these "transitionV stages in the freezing of water similar to the transition stages occurring in the transformation of austenite into pearlite? To clarify, let us consider in Fig. 1 the mechanism of the transformation of eutectoid steel from its austenitic to its pearlitic condition as it cools slowly through its thermal critical range. It is generally admitted that this transformation is the result of two distinct phenomena: (1) the allotropic change of gamma iron into alpha iron and (2) the crystallizing out of solution of the carbide Fe3C. Whether this crystallizing of Fe3C implies also its formation is immaterial for our purpose. In other words, whether it is the carbon in atomic dispersion which is present in gamma iron or molecules of Fe3C has no bearing upon the matter to be discussed. The transformation of gamma iron into alpha iron cannot take place suddenly. It must of necessity be progressive, regardless of the speed with which it may take place. At A, for instance, there would be present AB gamma iron and BC alpha iron. The distance MN does not refer to falling temperature, but to the passage of time. It may be assumed that the transformation takes place at a constant temperature (the Ar321 point). In a similar way, the crystallization of Fe3C out of the austenite solid solution must be progressive as depicted between M and N. At A there would be present AB gamma iron, BC alpha iron, CD carbon dissolved in gamma and in alpha iron and DE Fe3C. This condition may be described according to individual preference as martensite or troostite. To sum up, can the metal pass from condition

Jan 1, 1931

By W. T. Hicks

Visual observation of the oxidation of columbium shows that the protective behavior noted previously in gravimetric work in the early stages of the reaction below 600°C and throughout the reaction at 640°C is associated with an adherent oxide. The fact that the oxide is seen to move outward from the metal at temperatures from 550° to 935°C implies that the reaction takes place at the oxide-metal interface throughout this temperature range. THE work described in this paper further clarifies the complex oxidation kinetics of Cb revealed, for example, by the continuous gravimetric studies of T. L. Kolski.1 Time-lapse motion picture studies reveal details of the reaction not provided by a study of the combustion products. EXPERIMENTAL PROCEDURE Cb specimens were prepared from material with the following typical analysis: 0, 0.03 pct; N, 0.002 pct; C, 0.006 pct; Ta, 0.04 pct; Fe, 0.01 pct; Ni <0.003 pct; and Cr <0.003 pct. Arc-cast ingots were swaged and cold rolled into slabs. These slabs were machined into blocks 7/16 by 7/16 by 7/16 in; 1/16-in. holes were drilled through the large face of the blocks for suspension. The samples were then de-greased and annealed 1 hr at 1200°C in vacuum. The sample was suspended by a platinum and Pt 10 pct Rh thermocouple inside a 1-in. quartz tube in a Kanthal wound furnace (2 in. OD by 4 in. long) equipped with windows 1/2 in. sq. A Cine-Kodak Special II 16 mm motion picture camera was trained on the sample through a Spencer microscope adjusted so that a magnification of X1.5 resulted on the film. Super Anscochrome film was used to record the events in color. Argon was flushed through the furnace while the sample came to temperature. The argon was then replaced by a stream of dry oxygen at 1 atm. Pictures were taken at the rate of eight per second for about 20 sec during the change of atmosphere. Then by use of a Stevens time-lapse device pictures were taken at the rate of four per minute starting within 1 min of the initial oxygen flow. In this manner continuous visual records of the oxidation of pure Cb

Jan 1, 1962

By Albert Sauveur

SOME writers believe that when austenite transforms completely into pearlite on slow cooling through the thermal critical range, such transformation does not imply the formation of any of the so-called transition constituents: martensite, troostite and sorbite. Might it not be claimed with as much justification that when water freezes it does so suddenly, solid ice being obtained without passing through the intermediate stages of ice and water? Obviously, regardless of the speed of solidification, this would be erroneous. Before reaching the completed solid condition, this must of necessity pass through an unbroken series of stages when the system consists of mixtures of water and of ice, the former decreasing and the latter increasing in amount. Are not these "transition" stages in the freezing of water similar to the transition stages occurring in the transformation of austenite into pearlite? To clarify, let us consider in Fig. 1 the mechanism of the transformation of eutectoid steel from its austenitic to its pearlitic condition as it cools slowly through its thermal critical range. It is generally admitted that this transformation is the result of two distinct phenomena: (1) the allotropic change of gamma iron into alpha iron and (2) the crystallizing out of solution of the carbide Fe3C. Whether this crystallizing of Fe3C implies also its formation is immaterial for our purpose. In other words, whether it is the carbon in atomic dispersion which is present in gamma iron or molecules of Fe3C has no bearing upon the matter to be discussed. The transformation of gamma iron into alpha iron cannot take place suddenly. It must of necessity be progressive, regardless of the speed with which it may take place. At A, for instance, there would be present AB gamma iron and BC alpha iron. The distance MN does not refer to falling temperature, but to the passage of time. It may be assumed that the transformation takes place at a constant temperature (the Ar321 point). In a similar way, the crystallization of Fe3C out of the austenite solid solution must be progressive as depicted between M and N. At A there would be present AB gamma iron, BC alpha iron, CD carbon dissolved in gamma and in alpha iron and DE Fe3C. This condition may be described according to individual preference as martensite or troostite. To sum up, can the metal pass from condition

Jan 1, 1931

ALABAMA. Aldrich, Aldrich, W. F. Anmston, Noble, A. E Bessemen, Abbott, C E, Fergusson, V Birmingham, Aldrich, T. H, Aldrich, T. H, Jr, Bowron, J, Burbidge, T A, Collord, G L, Crockard, F H, Davis, F H, Dimmick, F. D., Hiller, E., Johnson, G R, Ludwig, C P., McCormack, G B., McCrery, Peters, R , Jr , Phillips, W B, Ramsay, E ,Shook, A. M Car bon Hall, Pill, J R Emsley, Williams, E P Gadsden, Hudson, J B , Helena, Squire, J Holt, Shook, J W. Huntnnlle, Moss Lehigh, Toulmin. Rock Run, Garvin, J. M. Sheffield, Miller, D I Tusscaloosa, McCausland, E J , Woodward, Woodward, A. H

Jan 1, 1910

By J. Leja, N. Sheikh

The stability of lead ethyl xanthate precipitate in aqueous environment of different pH (4.5 to 10.5) and at temperatures 25°C-60°C was investigated. Dissolution leads to a wide variation of pH, xanthate, and lead ions concentration in solution and to a deposition of solid products of reactions. X-ray diffraction patterns of these solids enabled identification of Pb(OH)3, PbCO3, and PbS as constituents of the remaining undecomposed Pb(EtX)1, together with some unidentified compounds (which give rise to intensive peaks with d values of 2.82A and 1.71A, and numerous peaks of lesser intensity).

Jan 1, 1974

By R. R. Klimpel Discussion by C. C. Harris, L. G. Austin

C. C. Harris (Columbia University) — The authors &apos; have presented relationships for the random division of a magnitude into r + l parts taking account of the order of selection. Interpreting their model in comminution terms, their Eqs. 7, 9 and 11 refer to the one-dimensional case; that is, to the subdivision of a long thin rod at random. It is assumed that the fragments may be indefinitely small. Real materials, however, are limited in the degree of subdivision which can be attained through the intervention of practical restrictions. One in fine grinding is the depletion of microflaws as material becomes finer. Another is the

Jan 1, 1969

NEW MEMBERS. The following list comprises the names of those persons who became members during the month of October, 1913: Members. BARNES, KENNETT F., Secty Granby Min. & Smelting Co., St. Louis, Mo. BILLINGSLEY, PAUL, Geol 526 Hennessy Bldg., Butte, Mont. BLANCHORD, RALPH C., Geol 3 Lombard St., London, England. BOYLE, ALBERT C., Jr., Prof. of Min. and Met., University of Wyoming, Laramie, Wyo. BRADFORD, JULIUS S., Min. Engr Chiksan Mining Co., Chiksan, Korea: CLEMES, ALFRED W., Min. Engr P. 0. Box 6,88, Moronic, Ariz. COPELAND, DURWARD, Met Cia. Estamifera de Llallagua, Bolivia, So. America. CRAWFORD, JOHN, JR., Mgr Noble Elec. Steel Co., Heroult, Shasta Co., Cal.

Jan 11, 1913

By K. D. Hester, A. C. Anderson

The Elliot Lake uranium deposits are contained in a pebble conglomerate which is similar throughout the basin. This paper compares the solid-liquid separation circuits of two nominal 3000 T/d acid leach uranium concentrates treating Elliot Lake ore. One concentrator employed rotary vacuum drum filtration for solids removal and washing, the .other used counter current decantation in torque arm thickeners. Capital and operating costs, operation and maintenance, and metallurgical performance of the two solution recovery methods are compared and contrasted. A recent development, removal of the sand fraction ahead of C.C.D. and separate sand washing in hydraulic cyclones, is also discussed.

Jan 1, 1973

NEW MEMBER, The following list comprises the names of those persons who became members during the period Mar. 10 to Apr. 10, 1915: Members ADAMS, Louis WINFIELD, Supt., Rolling Mills, Lehigh Plant, Bethlehem Steel Co., So. Bethlehem, Pa.. ALLEN, ARTHUR WATTS, Mine Mgr Rodeo, San Juan, Argentina., BALL, EDWIN MARCOTTEL, Mine Supt., Ishkooda. Mines, Care Tenn. Coal, Iron & R. R. Co., H.F.D. 1, Birmingham, Ala. BOLN, CHARLES A., Oil salesman 135 S. 2d St., Philadelphia., Pa. BOYD, DAVID F., Naval Officer Navy Department, Washington, D. C. CAPERTON, GEORGE HENRY Charleston, W. Va. COGGESHALL, GEORGE W., Chem. Engr., Institute of Industrial Research, Washington D C

Jan 5, 1915

Coal Division Industrial Minerals Division Minerals Beneficiation Division Mining, Geology and Geophysics Division Council Will Mitchell, Jr, Chairman (MBD), Kenneth L Cook, Vice-Chairman (MGGD). Edward L Clark (MGGD), Raymond B Ladoo (Ind Min Div), Sandford S Cole (Ind Mm Div), Norman L Weiss (MBD), C T Hayden (Coal), H F Yancey (Coal), Clayton G Ball (MED), P De Bruyn (MIED), Arnold Buzzalini, Secretary, AIME, 29 West 39th Street, New York 18, N Y Mining Branch Advisory Committee Will Mitchell, Jr, Chairman, Grover J Holt, J B Morrow, J L Gillson, Edward G Fox, S S Cole, Roger V Pierce, Norman L Weiss. H C Weed. J R Van Pelt

Jan 1, 1956

By P. D. Hunt, B. Tani, M. G. Chasanov, R. Schablaske

The Zn-Vphase diagram was studied by thermal. metallographic, X-ray, and sampling techniques. Three ternary phase equilibria were observed: Mutual solid solubilities in vanadium and zinc appear to be negligible. The liquidus line is retrograde from 670° to 756°C. 1 HE only information in the literature relating to the Zn-V system was a study of corrosion of vanadium by liquid zinc&apos; and an examination of the effectiveness of zinc coatings in protecting vanadium-base alloys from oxidation at high temperatures.2 Establishment of the Zn-V phase diagram was undertaken as part of a study of transition metal solubilities in liquid metal solvents. Chemical, metallographic, thermal, and X-ray diffraction analyses were used to determine the diagram. MATERIALS AND EXPERIMENTAL PROCEDURES Vanadium (99.86 pct) in the form of powder and small chips was employed. Stick zinc (99.99 pct; major impurities: 10 to 15 ppm Pb and 20 ppm Cu) was used in the liquidus determinations and thermal analyses; zinc powder (98.80 pct) was used to prepare intermediate compositions. The liquidus lines were determined by chemical analysis of filtered samples of the saturated melts. The apparatus and sampling techniques were similar to those described by Martin, et al.3 The entire metal sample was dissolved to preclude analytical errors due to segregation on cooling. Vanadium was determined amperometrically, using iron (11) as the titrant,4 to an estimated accuracy of 1 pct. Standard techniques of thermal analysis were employed to examine alloy specimens contained in alumina crucibles under helium. Heating and cooling rates were about 1°C per min. At least five heating and cooling cycles over the range 420° to 700°C were performed for each of two Zn-15 pct V alloys. A Zn-0.2 pct V alloy was used in the determination of the eutectic temperature. The separation of intermediate phases from zinc-rich alloys was carried out by selective leaching with ammonium nitrate solutions. For further investigation of intermediate phases 1/4 in. diam powder compacts were prepared by pressing at 80,000 psi and were annealed in argon at 415" to 450°C for 10 days. Larger quantities of intermediate phases were prepared in sealed tantalum capsules heated in a rocking furnace. Temperatures were determined to an estimated accuracy of 0.5°C with a Pt/Pt-10 pct Rh thermo-

Jan 1, 1963

By J. H. Swislzer

TWO-LIQUID miscibility gaps have been found to exist in both the CaO-SiO, system above 1705 and the Cr,03 system above 2200"c. Glasser and 0sborn3 studied the extension of these miscibility gaps into the Ca0-Si0,-Crz03 ternary system and reported that the two-liquid region is not present at temperatures below the monotectic temperature of 1705°C in the CaO-SiO, system. The present authors, in connection with other work on surface-tension measurements and foam stabilities in the same ternary system,4 observed that the miscibility gap exists at temperatures as low as 1600°C. A brief experimental study was devoted to deter- mining tie-line positions in the two-phase region. The technique used was to obtain a separation of phases at 1600°C, then to quench-in the high-temperature phases and obtain a chemical analysis of each phase. It was necessary to take special precautions in obtaining a phase separation because of a tendency toward emulsification of the two liquids. The procedure followed is described in the schematic drawing in Fig. 1. A small platinum crucible containing several pinholes on its sides was placed inside a larger platinum crucible. An excess of Crz03 was placed in the outer crucible, together with a prefused binary CaO-Si02 mixture, and the Cr203 was allowed to diffuse through the pinholes and saturate the same binary CaO-SiOl mixture in the smaller crucible. After equilibration at 1600°C, the inner crucible contained only the lighter liquid (liquid A) saturated with Cr203. The outer crucible contained layers of both liquids. Experimental data were obtained by analyzing the entire contents of the inner crucible and only the bottom layer of the larger crucible (liquid B). The upper layer of the outer crucible was not suitable for chemical-analysis purposes because dispersions of the second phase sometimes were found in the samples. The technique is described in more detail in Ref. 4. The same method was used by Grieveson and urkdoan&apos; to study a miscibility gap in sulfate-ferrite melts, where the liquids were difficult to separate because of similarities in density. In addition to the phase-separation experiments, a few others were conducted to obtain information

Jan 1, 1964

By F. S. Buffington, Morris Cohen

THERE is little quantitative information available concerning the effect of applied stress, in both the elastic and plastic ranges, on diffusion kinetics. Accordingly, a program has been undertaken to determine the rate of self-diffusion in high purity iron, with the specimens subjected to stress during the course of diffusion. Results are reported here for body-centered cubic iron at a diffusion temperature of 890°C. The iron used was 99.97 pct Fe, the principal impurities being 0.002 pct C, 0.008 pct 0, and 0.02 pct Si. The surface-decrease method of self-diffusion analysis was employed, and Fe55 Mn x-radiation, 2.9 years half-life) was the tracer element. Details of specimen preparation and equipment are given elsewhere.&apos; Disks of the high purity iron, % in. diam x 1/4 in. thick, were annealed at 890°C for 18 hr in dry hydrogen to produce large grains of a ferrite. The faces of the disks were then surface ground, and possible grinding stresses were relieved by annealing at 890 °C for 45 min in vacuum. A layer of radioactive iron 0.00186 cm thick was electroplated on one face of each disk. The self-diffusion coefficient was calculated from the ratio of the radiation intensities emanating from each of these faces, as measured before and after diffusion.&apos; The heating was carried out in a vacuum furnace (10-5 mm Hg) controlled to ±1.5°C. The specimens were loaded in compression between two quartz disks during the diffusion runs by means of a lever system operating through a vacuum seal. Thus one quartz disk was pressed directly against the radioactive face of the specimen, minimizing the vapor loss of radioactive iron. Steady-state creep occurred in all instances where permanent deformation could be detected, but the specimens did not exhibit appreciable transverse barreling until natural strains of 0.2 to 0.3 were attained. Essentially, the diffusion took place under uniaxial stress. The plastic strain in each case was obtained at the diffusion zone by measuring the diameter d there before and after the run: e = 2 In — do Let Du equal the self-diffusion coefficient which would have prevailed at the given temperature if no stress had been applied. This was calculated from the temperature-dependence equation which had been previously determined: —59,800 D, = 6.2 exp ( I sq cm per sec* [I]

Jan 1, 1953

By S. W. Zanolli

The history of labor relations in the coal industry of the United States is a study of its collective bargaining. This study of collective bargaining is largely the history of the United Mine Workers of America and its contractual relations with the various coal mining employers who have produced this country&apos;s coal over the years under a free enterprise system. There have been other unions in the picture from time to time and some coal miners have mined coal without representation by any union. Even today some 25% of the nation&apos;s coal is produced outside of the collective bargaining relationship with the UMWA. However, more than 100,000 coal mine wage employees - well over 75% of the total in the industry - are covered by labor agreements negotiated for them by the UMWA. Practically all of these work in bituminous mines.

Jan 12, 1972

[A AALSETH Earl P (M 51) Consult Geol Engr 2019 Eldorado Dr, Billings, Mont ABADIE Henry G (M 43) Asst to. Supt of Oper Long Beach Oil Dev Co 925 Harbor Plaza, Long Beach 2, Calif. ABBET Waldo (A 56) Asst Diet Oper Supt Sun Oil Co P 0 Box 66, Stowelt, Tex ABBOTT Clifton T (A 60) Apartado 677, Maracaibo, Venezuela ABBOTT Fred E Jr (M 59) Abqaiq Diet Mgr Arabian American Oil Co Dhahran, Saudi Arabia ABBOTT J L (M 56) Partner Pritchard & Abbott 1010 Ft Worth Natl Bk Bldg, Fort Worth 2, Tex ABBOTT Richard H (J 51) Partner Abbott & Howard 422 W Hermosa, San Antonio 12, Tex ABBOTT William G (M 50) Div Mgr Rice Engrg &. Operating Inc Box 1142, Hobbs, N. M. ABDERHALDEN Ronald R (J 59) Prod Engr Continental Oil Co Box 100, Carml, 111]

Jan 1, 1961

At Black Lake, Quebec, Lake Asbestos of Quebec Ltd., a wholly-owned subsidiary of American Smelting and Refining Co., has opened a $36-million mining and milling operation which will produce about 100,000 tons of asbestos fiber a year and add 7 pct to the Free World&apos;s supply. The orebody once lay beneath Black Lake, and readying the ore deposit for open pit mining meant removing about 37 million cu yd of overburden- 30 million cu yd by dredging and pumping, and 7 million by power shovels and trucks. The enormous amount of material to be dredged, control of drainage during dredging, the need to cope with drainage problems in the area and to provide for flood control to replace the regulating effect of the lake, posed unusual engineering challenges and required tremendous capital investment.

Jan 1, 1959

The phosphate pebble-bearing matrix in the Florida Phosphate Pebble Field has physical properties which make it readily adaptable to hydraulic transportation methods employing solids-handling pumps and pipelines. The abundance of water available, a practically flat terrain, low costs per ton-mile, and beneficiation of the matrix by agitation while being pumped have contributed to the popular choice of hydraulic transportation. Phosphate pebble mining in Florida, begun in the 1860&apos;s, first used high pressure water and solids-handling pumps for overburden removal about 1900. Removal of the average 25 ft of overburden was followed by hydraulic mining of the matrix, with 6-in. and 8-in. pumps handling 50 to 100 cu yds per hour being moved along the floor of the pit as they were advanced toward the face being undercut and slurried by hydraulic guns.

Jan 3, 1961

By C. Feng, C. Elbaum

AN investigation of the fracture plane of titanium, containing 0.5 wt pct to 1 wt pct 0, was recently carried out by fracturing large-grain specimens in a tensile jig at room and liquid air temperature. The experiments were carried out on strip specimens 3 to 5 mm wide, 2 mm thick and about 100 mm long. The specimens consisted of several grains, each occupying the entire cross section of the strip and extending over a length varying from 5 to 20 mm. These specimens were prepared by a method described elsewhere.&apos; The identification of the fracture plane was possible in twelve of approximately thirty crystals investigated. In some cases severe local distortion took place near the fracture and prevented identification of the fracture plane. On, at least, three occasions the fracture propagated in a helicoidal

Jan 1, 1959

Weston Portable Electrodynamometer The Weston Electrical Instrument Co. of Newark, N. J., believes that problems hitherto considered impossible of solution in the designing of portable electrodynamometers have been solved in its new models. The voltmeter, Model 341, is an instrument&apos; of precision adapted to use on alterating- or direct-current circuits, guaranteed to an accuracy of 0.25 per cent. full-scale value either on direct or alternating-current circuits of any frequency to 133 cycles per second and commercial frequencies even as high as 500 cycles per second with very slight error. The polyphase electrodynamometer, Model 329, is accurate to 0.5 per cent. under the same conditions.; Double ranges are furnished in all instruments of this model. All current ranges can be used for 100 per cent. overload indefinitely without introducing error in Models 310 and 329.

Jan 12, 1915