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By V. O. Struebing, K. A. Johnson, F. H. Ellinger, C. C. Land

The system Pu-Ce-(Pu,Ce)Co2 has been investigated by thermal, micrographic, and X-ray diffraction methods. The principal characteristics of this system were found to be: 1) a "eutectic" valley extending across the phase diagram from the 6 Pu/Pu3 Co eutectic at 408°C to the 7 Ce/Ce24Co11 eutectic at 42Z°C, the maximum temperature in the valley being 443°C; 2) three ternary inter mediate phases, each having an appreciable mutual solid solubility for plutonium and cerium; 3) eleven four-phase equilibria comprising one eutectic, four peritectics, and six Class II reactions; 4) a pseudobinary section between the ternary phase A and the y Ce solid solution, and another such section between the 6 Pu solid solution and the 77 phase (Pu3 CO) containing cerium in solid solution. ALLOYS of plutonium that are completely molten at temperatures in the vicinity of 500°C are of interest for use in the liquid state as fast reactor fuels. Since exploratory work1,2 on Pu-Ce-Co alloys had indicated that a "eutectic" valley extended across the ternary system between the Pu-co[6 Pu/n (Pu3co)] and the Ce-CO[? Ce/? (ce24co11)] binary eutectics, thus allowing alloys of any plutonium concentration to be selected within the temperature limitation, the present investigation was begun for the purpose of accurately defining the "eutectic" valley. However, when the existence of three ternary intermediate phases and the consequent complexity of the liquid-solid equilibria were discovered, the investigation was expanded to cover the complete system, except for the corner between the isomorphous series PuCo2-CeCo2 and pure cobalt. 1) EXPERIMENTAL The purities of the alloy components are given in Table I. Alloy buttons, each weighing about 5 g, were prepared by arc melting the accurately weighed components (±0.1 mg) under a purified He-Ar atmosphere. Weight loss as a result of melting was usually less than 1 part in 1000; therefore, the buttons were not chemically analyzed. One half of each button was re-melted by induction heating in vacuo in a magnesia crucible and furnace-cooled, so as to produce a somewhat coarser microstructure than that of the rapidly cooled arc-melted button. About 20 g of each alloy to be examined by thermal analysis were remelted in vacuo in a tantalum crucible of the inverted thermocouple well type. The thermal, X-ray diffraction, heat treating, and micrographic methods used in this investigation were essentially the same as have been described in earlier reports.3,4 Two etchants for these alloys were found to be satisfactory: A) 8 (parts by volume) orthophosphoric acid, 5 ethanol, and 5 glycol; B) 7 tetraphosphoric acid, 36 water, and 57 2-ethoxyethanol. Etchant A was used at 5 to 6 v for 15 to 20 sec, and etchant B was used at 10 v for 10 sec. 2) THE LIMITING BINARY SYSTEMS 2.1) Plutonium-Cerium. The phase relationships of this system have been investigated by Ellinger, Land, and Cramer,5 and by Selle and Etter.6 The over-all agreement of their phase diagrams is good, but there are some discrepancies in the positions of some phase

Jan 1, 1967

By P. R. Swann, J. G. Parr

Quenched structures were studied in alloys containing up to 12.5 pct cobalt. The subsequent decomposition of a 10 pct cobalt retained-ß phase alloy was investigated using metallographic and X-ray diffraction methods. Hardness measurements also were made during the decomposition process. Precipitation of Ti2Co is by nucleation and growth; and an activation energy of 50,000 cal per mole was determined. The values of the coefficient ß suggest that the precipitate is pearlitic at temperatures between 450 and 475°C, and spheroidal between 500 and 525°C. THIS paper describes part of a series of invesligations into phase transformations in binary alloys of titanium with transition elements. The general approach is similar to that taken in work on titanium-iron and titanium-nickel alloys.' Previous investigators'' have established the titanium-rich end of the titanium-cobalt phase diagram, reproduced in Fig. 1. Orrell and Fontana' showed that alloys containing more than about 6 pct" cobalt quenched from the ß range, produced 100 pcl retained-p phase. The isothermal decomposition of alloys containing between 0.8 pct Co and 15.5 pct CO was investigated by the same workers in the temperature range 650 to 1000°C. They reported that these alloys transformed into a or Ti,Co depending on the cobalt content, but no quantitative data were given. In the work to be described a series of alloys containing 0.8 pct Co to 12.5 pct Co was examined in the quenched condition. The 10 pct Co alloy (the lowest cobalt content to retain 100 pct ß on quenching) was selected for further work on the tempering kinetics of the ß decomposition. Experimental Procedure Since our own melting equipment was not installed at the outset of this work, the Physical Metallurgy Division of the Department of Mines and Technical Surveys (Ottawa, Canada) prepared the alloys. These were made of Japanese sponge, (which when melted had a value of 103 DPH, using a 1-kg load), and electrolytically prepared cobalt. The al- loys, made up to contain 0.8, 1.6, 3.3, 5.8, 8.3, 10.0 and 12.5 pct Co, were homogenized by swaging into rods at 900°C. Filings were taken from the rods, and any iron chips from the file were separated magnetically. Size fractions of both plus and minus 200 mesh (about 75p) were shown by their constitution, after annealing just below the eutectoid temperature, to contain the same cobalt content. Consequently, it was permissible to use the —200-mesh fraction, knowing it to be representative of the rod composition. Quenching in argon was carried out in a newly designed furnace, whose features include (1) an Inconel furnace tube, (2) a positive pressure of argon maintained at all times in the furnace—even when a sample is removed or inserted. The furnace is shown in Fig. 2 and is described in the Appendix. The tempering processes were carried out on powder samples sealed in evacuated quartz capsules. Since the highest tempering temperature was 525OC, no protection against reaction with the quartz was necessary. (Tests were made on filings of iodide titanium and showed no hardness increase after equivalent heat-treatments.) A thermocouple was attached to the capsule, which was heated to the

Jan 1, 1959

By D. J. Schmatz

DISCUSSION OF RESULTS The qualitative correlation between low-temperature ductility and prior high-temperature creep strain in nickel obtained in this investigation confirms the result obtained on high-purity brass by Chen and Machlin. However, the quantitative effect is much smaller in nickel. Comparison can be made on the basis of a prior high-temperature strain that is a certain percentage of the total high-temperature elongation to rupture. In the research of Chen and machlin, the prior high-temperature strain of 1/2 pct equaled 8.5 pct of the total high-temperature elongation at rupture. For nickel, in our experiments, 8.5 pct of 21.2 pct equals 1.8 pct. For eh = 1.8 pct, the loss in ductility in percent equals x 100 = b.5 pct. That is, for equivalent bo Formation of Beta Manganese-Type Structure in Iron-Aluminum-Manganese Alloys D. J. Schmatz IRON-aluminum alloys have gained much interest in the past few years for use as a base material for elevated-temperature alloys because of their excel- high-temperature strain the loss in low-temperature ductility is 8.5 pct for nickel as compared to 60 pct for pure a, brass. It is also interesting to note the observation that in nickel the low-temperature fractures, even at the most extreme high-temperature pre-strain, were partly trans crystalline and partly intercrystalline. In the case of a brass, these fractures were completely intercrystalline. According to the data on the percent of the grain boundary area that is cracked, at 22 pct high-temperature elongation, about 12.5 pct of the grain boundary area does not carry load. Thus, the inter-crack areas are carrying a stress that is about 11 pct higher than the nominal stress. A simple model predicts that the overall elongation, which is primarily the elongation in the bulk of the specimen, will correspond to the nominal stress when the stress in the intercrack area equals the tensile strength. Quantitatively this model predicts the equation The form of this equation will agree with that found if the strain-hardening exponent, n, equals unity. Actually this model is too gross an approximation to yield good quantitative results. The question naturally arises as to whether in ordinary hot-working, such as hot-rolling, intercrys-talline cracks are introduced that affect the low-temperature properties. It appears that the answer is that such a possibility cannot be overlooked, if the hot-working induces tensile stresses at temperatures above the equicohesive temperature and if the material tends to be notch sensitive at low temperature. ACKNOWLEDGMENT This research was supported by the Aeronautical Research Laboratory, Directorate of Research, Wright Air Development Center, United States Air Force. REFERENCES lC. Zener: Fracturing of Metals, 1948, Cleveland, ASM. 'H. C. Chang and N. J. Grant: Mechanism of Intercrystalline Fracture. AIME Trans., 1956, voL 8, p. 544; lownal of Metals, May, 1956. 'E. S. Machlin. CreepRupt ure by Vacancy Condensation, AIME Trans., 1956, vol. 8, p. 106; lownd of Metals, February, 1956 'C. Chen and E. S. Machlin: On a Mechanism of High-Temper at ure Inter-crystalline Cracking, lownd of Metals, July. 1957. p. 829. Alloys lent oxidation resistance. Binary alloys of aluminum in iron are ferritic and consequently have poor hot strength. Alloys of iron-aluminum-manganese were made in an attempt to produce an austenitic alloy containing sufficient aluminum to retain the oxidation resistance of binary alloys of iron-alumi-

Jan 1, 1960

By F. W. Warnaars

The Los Bronces copper deposit is located on the west side of the Andes Mountains in central Chile about 54 km (34 miles) northeast of Santiago. The deposit consists of a hydrothermal breccia complex that was emplaced in the western part of an earlier porphyry copper mineral system. This system exhibits propylitic, sericitic, silicic to potassic hydrothermal alteration with disseminated and stockwork copper-molybdenum sulfide mineralization over an area of about 12 km2 (5 sq. miles). The Rio Blanco Mine, about 800 m (0.5 miles) east of Los Bronces, is an underground block caving mine located in the central part of this system. The mineralization at Rio Blanco is characterized by one of the highest primary copper grades known for porphyry copper systems. Present mining at Los Bronces is from an open pit located in the northern part of a hydrothermal complex that is composed of at least seven different copper-bearing tourmaline breccia pipes. Together these pipe form one large contiguous body about 2 km (1.2 miles) long and 0.7 km (0.4 miles) wide at the surface. This body crops out at elevations of between 3.5 and 4.1 km (2 and 2.5 miles) above sea level. Each breccia pipe has a characteristic shape, matrix, type and degree of mineralization and alteration. Quartz, tourmaline, specularite, anhydrite, pyrite, chalcopyrite, sericite, chlorite, and rock flour are present in significant quantities in most breccia matrices. The clasts consist mainly of quartz monzonite, andesite, and minor amounts of quartz latite porphyry. The seven different breccia pipes are identified, from oldest to youngest, as Ghost, Central, Western, Infiernillo, Fine Gray, Anhydrite, and Donoso. The breccias coalesce, interfinger, or display gradational contacts. In places they form sharp contacts with each other and with the surrounding intrusive or volcanic host rocks. Early breccias are disrupted or cut by subsequent breccia events. Explosive emplacement was followed by collapse after the release of hydrothermal pressures. The Los Bronces breccia complex has sharp contacts with the surrounding intrusive stock and andesites. These contacts dip inward on the north, west, and south margins. The eastern contact is nearly vertical and/or dips slightly outward and suggests a westward tilting of the body of about 15° after emplacement. The breccia complex is not fully explored at depth, but is known to extend at least below the 3 km (2 mile) elevation in its central eastern part, about 1 km (0.6 miles) below the highest breccia outcrop. Primary copper sulfide minerals are most abundant in the Donoso and Infiernillo breccias where the matrix consists mostly of tourmaline, quartz, sulfides, specularite, and/or chlorite with minor amounts of rock flour, sericite, and clay. The volume of the matrix material is mostly smaller than in the other breccias. Secondary enrichment enhanced the primary copper grade in the southern two-thirds of the Los Bronces breccia complex and in much of the surrounding porphyry system. Primary grades of 0.3% to 0.5% copper have been enriched to approximately 0.9%. This enrichment may extend from surface outcrops to a depth of more than 500 m (1, 640 ft) in more permeable parts of the breccia complex. A leached and oxidized capping of variable thickness covers a large part of the enriched layer and exceeds 300 m (984 ft) at one location. The shape and depth of the enrichment blanket and the capping suggest that the enrichment process is still active.

Jan 1, 1983

By S. A. Braley

THE first commercial production of bituminous coal in the United States was in 1820, and formation of acid in the areas from which the coal was removed began at that time. Thus it is 130 years since the development of mine acid began. The coal operator has had to deal with the acid water produced in his mines, and his losses from corrosion of pumps and equipment have been tremendous. Other industries and the public have been forced to spend large amounts for their water requirements because of the acid discharge from the mines. There are many contradictions in the literature on this subject probably because of variations in the analytical procedures followed and differences in the methods of calculation and reporting. The opinions previously expressed may be summarized as follows: The production of mine acid has been looked upon as a simple chemical reaction wherein the oxygen of the air has reacted with pyrite to produce ferrous sulphate and free sulphuric acid. This reaction appears in many chemistry texts and generally has not been considered worthy of further study. Since the measurement of hydrogen ion concentration or activity was developed and expressed in terms of pH, indicator and instrumental methods for pH determination have become readily available, making it natural to think of it as a measure of acid content. Special purpose analytical methods applicable to potable waters, sewage effluents, and boiler waters, based in general upon the determination of what may be regarded as impurities, have been applied to more concentrated solutions constituting mine discharges, without reference to the fact that these specialized procedures had been developed to serve as operating guides for water-treatment plants. It has been assumed that the pounds of acid deliv- Table I. Showing pH and Titratable Acid of Varying Concentrations of Ferrous and Ferric Sulphates Ferric Ferrous ion Acldfty Ion Acidity (Fe+++) ppm CaCO3 We++) ppm CaCOa ppm PA equiv. PPm pH equiv. 11.200 1.80 30,000 11,200 3.98 20,000 5,600 2.01 15,000 5,600 4.15 10,000 2,800 2.21 7,500 2,800 4.41 5,000 1.120 2.48 3,000 1,400 4.68 2.500 560 2.60 1,500 140 5.00 250 280 2.65 750 28 5.00 50 112 2.81 300 56 3.07 150 28 3.38 75 ered by a mine was roughly a constant varying with the number of acres mined, and that the concentration of the acid in the drainage was inversely proportional to the volume of flow. Increased flow was thought to result in a dilution of the acid produced. When the Sanitary Water Board of the Commonwealth of Pennsylvania established a fellowship at Mellon Institute, the first approach to the problem was to review some of the chemical reactions involved and their relation to acid production. Since the sulphates of iron were among the principal constituents of coal-mine drainage, the first studies were based upon solutions of chemically pure ferrous and ferric sulphate. These are both neutral salts, that is, the iron and the sulphate are equivalent, but they produce acid reactions in water solution because as salts of strong acids with weak bases, they hydrolyze to form acid solutions. Solutions of each salt, of varying concentrations, were prepared and the pH, titrable acidity and iron and sulphate

Jan 1, 1952

Jan 1, 1944

Jan 1, 1957

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Jan 2, 1967

Jan 1, 1949

Jan 1, 1913

By Charles R. Keyes

PAGE. I Introduction,........674 11. Occurrence............ 676 III. Geology of Death Valley BoRate-Region,....677 1. Surface.Relief ......677 2. Geologic Formations,....680 3. Geotectonics,..684 IV. FURnace Canyon Deposits..686 1. General Features..686 2. Geologic Structure..688 3. Ores.....690 4. Typical Section ...691 V. Lost Valley Deposits...693 VI. Mojave Desert Deposits..693 1. Distribution....693 2. Geologic Structure ........694 3. Ores............ 696 VII. Santa Clara Valley Deposits .699 1. Distribution....699 2. Geologic Structure..700 3. Ores.....700 VIII. Ventura County Deposits..701 IX. Geologic Occurrence of Borax .701 1. Original Sources...701 2. Solfataric Borax...702 3. Lacustrine Borax...703 4. Marsh Borax....703 5. Terranal Borax...704 X. Chemistry of Natural Borates.... 705 1. General Considerations.....705 2. Composition of Saline Waters...706 3. Solubility of Components....707 4. Time-Element in Water.Concentrations . 707 5. Effect of Temperature.....708 6. Effect of Pressure......709 XI. Occurrence of Other Commercial Salines,.... 709 I. Introduction. A complete transforrnation has taken place in the borax industry during the year 1908. A most remarkable factor in

Jan 1, 1910

By J. M. Boutwell

PAGE I. Introduction,.......541 II. General Geography,......542 III. General Geology,......544 1. Sedimentary Rocks,..... 544 2. Igneous Rocks,...... 545 3. Areal Geology,.......546 4. Structural Geology......547 IV. General Character of Ore-Deposits,...548 V. Genesis of the Disseminated Ore in Monzonite,.... 549 1. General,........549 2. Character and Occurrence,... 649 3. Genesis,....... 550 4. Superficial Alteration.....553 5. Conclusion......553 VI. Genesis of the Ore in Fissures,...553 1. Character........... 553 2 Occurrence......554 3. Deposition...... 556 4. Transporting Agent....555 6. Immediate Causes of Deposition..556 6. Superficial Alteration....564 7. Conclusionl ..... 565 VII. Genesis of the Copper-Ore in Limestone...... 566 1. Character......566 2. Occurrencel .....566 3. Deposition......567 4. Relation of Fissures.....569 5. Relation of Intrusives,...571 6. Superficial Alteration....575 7. Conclusion......578 VIII. Periods of Ore-Deposition....578 IX. Dates of Mineralization.....579 X. General Conclusions.....580 I. Introduction. The object of this paper is to present a concise statement on the genesis of the copper- and lead-deposits of the Bingham

Jan 1, 1906

By Charles W. Carter, Alfred H. Bell

In 1943, Illinois produced 82,256,000 bbl. of oil, or 5.5 per cent of the total for the United States, and ranked sixth in the nation in oil production. This represents a decline of 23 per cent from 1942, when the total Illinois production was 106,ggo,o~~ bbl. and Illinois ranked fifth. The daily average production for 1943 was approximately 225,000 bbl. Daily averages by months were as follows: Jan......... 238,000 July......... 218,000 Feb......... 240,000 Aug......... 216,000 Mar......... 237,qoo Sept........ 220,ooo Apr......... 230,000 Oct......... 220,000 May....... 221,000 Nov......... 223,000 June......; . 222,000 Dec......... z18,ooo This shows that most of the decline during the year took place between March and May, and that for the last eight months of 1943 production has been essentially steady. This means that there has been enough production from new wells drilled to balance the natural decline of the Older wells. The trends of drilling and production are shown in Fig. I and Table 3.

Jan 1, 1944

By Alfred H. Bell, Charles W. Carter

In 1943, Illinois produced 82,256,000 bbl. of oil, or 5.5 per cent of the total for the United States, and ranked sixth in the nation in oil production. This represents a decline of 23 per cent from 1942, when the total Illinois production was 106,ggo,o~~ bbl. and Illinois ranked fifth. The daily average production for 1943 was approximately 225,000 bbl. Daily averages by months were as follows: Jan......... 238,000 July......... 218,000 Feb......... 240,000 Aug......... 216,000 Mar......... 237,qoo Sept........ 220,ooo Apr......... 230,000 Oct......... 220,000 May....... 221,000 Nov......... 223,000 June......; . 222,000 Dec......... z18,ooo This shows that most of the decline during the year took place between March and May, and that for the last eight months of 1943 production has been essentially steady. This means that there has been enough production from new wells drilled to balance the natural decline of the Older wells. The trends of drilling and production are shown in Fig. I and Table 3.

Jan 1, 1944

Jan 1, 1965

By C. A. Meissner

The; following is a further discussion of the paper of James Qayley, " The Application of Dry-Air Blast to the Manufacture of Iron " (Trans., xxxv., 746), with special reference to his supplementary paper (Bi-Monthly Bulletin, No. 4, July, 1905, pp. 797 to 819), and to the paper of J. E. Johnson, Jr., " Notes on the Physical Action of the Blast Furnace " (Bi-Monthly Bulletin, No. 5, September, 1905, pp. 1111 to 1146). Mr. Gayley's paper has been discussed also by E. Windsor Richards, R. w. Raymond, E. H. Saniter, W. J. Poster, H. M. Howe, V, Pendred, B. H. Thwaite, James Gayley and Alexander Pourcel (Trans., xxxv., pp. 1022 to 1042), Joseph W. Richards (Bi-Monthly Bulletin, No. 4, July, 1905, pp. '703 to 718); T. W. Robinson (Bi-Monthly Bulletin, No. 4, July, 1905, pp. 788 to 796); C. B. Dudley, R. W. Raymond, J. E. Johnson, Jr., W. F. Mattes, James Gayley, David Baker, John Birkin-bine and F. E. Bachman (Bi-Monthly Bulletin, No. 5, Septem-

Jan 1, 1907

By Howard R. Keil

CARLTON mill in the Cripple Creek district, 45 miles southwest of Colorado Springs, Colo., has been in operation for approximately three years, treating the custom sulpho-telluride ores formerly handled by the Golden Cycle mill in Colorado Springs. At the new mill the pyrite-telluride flotation concentrates have been roasted, prior to cyanidation, in a Dorrco FluoSolids reactor, which has proved capable of yielding calcine readily amenable to cyanidation. Incoming ores are crushed at Carlton to 5/8 in. and sampled in 30 to 75-ton lots before the individual lots are mixed in the fine ore bin. The composite ore then goes to the grinding circuit. Classifier overflow from the grinding circuit is treated by flotation to produce a concentrate containing approximately 85 pct of the values in 5 pct of the weight. The flotation concentrate goes to the FluoSolids reactor prior to cyanidation. Cyanide solution values are recovered by zinc dust precipitation. Flotation tailings are thickened and cyanided, the values from this part of the circuit being recovered from solution by activated carbon.

Jan 12, 1954

The Ural Mountains, which were formerly the dividing line between Asia and Siberia, area chain of low mountains, the highest peaks reaching only a little over 5000 ft. The country has been much eroded and the mountains now appear as rounded hills. In the central and northern parts turf swamps abound. The range is covered with forests except at the extreme southern end. The trees are mostly pine. Birch grows on cut-over areas, but never to large size. The rivers are small or the fall is slight, so no large water powers are available. A series of rivers with a north and south course, and which are navigable for long distances, furnish cheap transportation during the summer months. Railroad communications are very insufficient. The first active exploitation of the mineral wealth was initiated by Peter the Great, who sought iron and copper for use in his wars against the Swedes. He selected a blacksmith named Demidoff to supervise operations and gave him rights to most of the Ural and to the Altai. The Nijni Tagil Estates are still in the possession of the Demidoff family. The original large grant was subsequently subdivided through inheritance and marriage, but the Ural is still a country of very large estates, some of them held as leases only and some of them by actual ownership.

Jan 6, 1919

By David D. Rabb

Under the auspices of the Atomic Energy Commission, the Lawrence Radiation Laboratory of the University of California analyzed an experiment to provide information as to whether the chimney of broken rock produced by a deeply buried nuclear explosive could be "drawn" by conventional techniques. Since many low-grade disseminated ore-bodies occur in a granite media, the experiment took place in a granodiorite-quartz monzonite intrusive porphyry in the Nevada Test Site as a follow-up to the Department of Defense's Hardhat detonation in February 1962. For emplacement of the nuclear device, a 12 ¼ - in. pilot hole was reamed to a diameter of 44 in. and a depth of 950 ft in one pass using a Hughes multiple-cluster rotary bit. It was then cased to 36 in. ID. The center of the explosive device was located 938.85 ft below the collar. The yield of the device was predicted to be 5 kilotons, or an equivalent of 5000 tons of TNT; the yield was later confirmed by chemical means to be 5.4 kilotons.

Jan 3, 1964