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By T. S. Fuller

THE work of D. J. McAdam1,2 at the U. S. Naval Engineering Experiment Station, Annapolis, Md., on what has been called by him "corrosion fatigue" has focussed the attention of the engineering profession in general, and of those interested especially in the study of corrosion in particular, on the importance of making tests which will indicate as nearly as possible what can be expected from a given material in service. Pitting is unquestionably the chief agent operating so tremendously to reduce fatigue limits, but in the light of previous work3, 4, 5, 6, 7, 8 it is fair to assume that absorbed hydrogen resulting from the action of the corroding medium upon steel may, under certain conditions, have a perceptible influence. The experiments described in this paper deal more precisely with stressless corrosion, or "prior-corrosion fatigue, "9 and have been carried out to test such an assumption, to segregate, if possible, the effect of pitting from that of absorbed hydrogen, and although very preliminary in nature they indicate results which are striking.

Jan 1, 1929

By Donald J. Drinkwater, M. C. Fuerstenau

Many important contributions to the more fundamental aspects of mineral processing have been made this past year. Mular1 researched the flotation characteristics of pure zinc oxide and also samples that had been doped with Al+++ and Cu++. Correlation of the response of pure zinc oxide to oleate flotation with a calculated zpc (from solution equilibrium) suggests that adsorption of oleate ion is coulombic in nature. Doping the sample with Al+++ (which will make the ZnO more n-type) had a marked effect on the maximum value of pH at which 50% recovery was obtained at constant collector addition. That is, when 0.5 mole percent Al+++ was added, the pH for 50% recovery was reduced by about four units. Treatment with Cu++ was found to have little effect on the flotation response of zinc oxide, even for additions of one mole percent. Since the zero points of charge of the Al+++ doped powders were not measured, it was not possible to correlate flotation data of these samples directly with charge phenomena.

Jan 2, 1966

By T. S. Fuller

The work of D. J. McAdam, Jr.1,2 at the U. S. Naval Engineering Experiment Station, Annapolis, Md., on what has been called by him "corrosion-fatigue" has focussed the attention of the engineering profession in general, and of those interested especially in the study of corrosion in particular, on the importance of making tests which will indicate as nearly as possible what can be expected from a given material in service. Pitting is unquestionably the chief agent operating so tremendously to reduce fatigue limits, but in the light of previous work3, 4, 5, 6, 7, 8 it is fair to assume that absorbed hydrogen resulting from the action of the corroding medium upon steel may, under certain conditions, have a perceptible influence. The experiments described in this paper deal more precisely with stressless corrosion, or "prior-corrosion fatigue,"9 and have been carried out to test such an assumption, to segregate, if possible, the effect of pitting from that of absorbed hydrogen, and although very preliminary in nature they indicate results which are striking.

Jan 1, 1929

By T. S. Fuller

The work of D. J. McAdam, Jr.1,2 at the U. S. Naval Engineering Experiment Station, Annapolis, Md., on what has been called by him "corrosion-fatigue" has focussed the attention of the engineering profession in general, and of those interested especially in the study of corrosion in particular, on the importance of making tests which will indicate as nearly as possible what can be expected from a given material in service. Pitting is unquestionably the chief agent operating so tremendously to reduce fatigue limits, but in the light of previous work3, 4, 5, 6, 7, 8 it is fair to assume that absorbed hydrogen resulting from the action of the corroding medium upon steel may, under certain conditions, have a perceptible influence. The experiments described in this paper deal more precisely with stressless corrosion, or "prior-corrosion fatigue,"9 and have been carried out to test such an assumption, to segregate, if possible, the effect of pitting from that of absorbed hydrogen, and although very preliminary in nature they indicate results which are striking.

Jan 1, 1929

By Charles D. Russell, L. H. Jenks, W. J. Leas

A detailed description is given of an experimental method for determining relative permeability of porous media to gas. Results are presented for natural and synthetic cores. The experimental data for two and three phase systems are compared. The reproduci-bility of the equilibrium gas saturation ii demonstrated and the effects due to a variation in rate of gas flow are discussed. An attempt is made to correlate total permeability and rock textural factors with relative permeability to gas. Capillary pressure curves obtained simultaneously with the relative permeability curves are shown to be equivalent to those obtained in conventional displacement cells. INTRODUCTION The advances in petroleum reservoir technology during the past decade have made increasingly apparent the desirability of a simple, rapid, reliable metliod for obtaining relative permeability data on small cores. Such data are needed in order to study fluid mechanics in porous media and for the more refined reservoir behavior prediction calculations now under development. The early experimental work in this field was done by Wyckoff and Botset1 who measured relative permeabilities for gas-liquid mixtures flowing through

Jan 1, 1950

By G. M. Ellis

When developing a mineral processing facility, the mining company management and engineering staff should have some knowledge of the construction industry in order to work with the contractors involved as a team. Of course, the situation varies with the nature of the project and its size, but relations among owners, engineers, and contractors always will be enhanced if the mining company has a knowledge of three construction industry facets: (1) the makeup of a construction company, (2) the functions performed by its staff, and (3) the various types of contracts and tendering procedures available. There are several options open to a company wishing to bring a new mine into production from the grass roots, depending upon corporate structure, capabilities, and financial strength. A company that already employs a substantial engineering staff may elect to manage and perform the design requirements itself, and may handle some or even all of the actual construction work. But in cases where bank financing is required, the loan is often dependent upon adequate professional construction help being used.

Jan 1, 1978

By H. M. Chance

The iron-ore deposits of the Hartville district are located near the new town of Guernsey, about 100 miles north of Cheyenne. The writer has been familiar with them since 1887, having visited the district several times for different clients— his last examination having been made in November and December, 1897. The deposits extend in a general N.E.-S.W. direction from a point in Section 33, Range 65 W., Township 28 N., on the west side of Whalen cañon, through Sections 4, 5, 6, 7 and 8 of Township 27 N. in the same Range, and over into Sections 1 and 12 of Township 27 N., Range 66 W. General Characteristics. The ore is a remarkably pure red hematite, extremely low in phosphorus, and carrying a small percentage of silica, as shown by analyses given below, and similar in many respects

Jan 1, 1901

By Clarence Zener

[ ] THE present investigation started in an attempt to understand certain details of the decomposition of austenite, and of the effect of alloying elements thereon. As the investigation proceeded it became apparent that not only these details, but all the general features of austenite decomposition, could be understood in terms of fundamental physical principles. Since the direct applicability of these physical principles has not been previously recognized, it was decided to incorporate the original results of the investigation into a review of the general subject of the kinetics of austenite decomposition. This review constitutes the present article. An extended summary of the results is given on pages 27 to 30. This article, which deals with the kinetics of phase transformations, may appropriately be considered as a sequel to two recent articles1,2 from this laboratory on the equilibrium relations in medium alloy steels.

Jan 1, 1946

By Alden B. Greninger

The study of mosaic structure of crystals1 has been confined until recently to the field of theoretical physics. Crystallographers, in general, have neglected the subject, although X-ray crystallographers constantly make use of formulas for intensities of X-ray reflection as modified by mosaic structure. Work on mosaic structure has centered chiefly on the task of proving or disproving the secondary-structure theory of Zwicky,² and very little attention has been paid to the visible imperfections of crystals. A. Goetz has been responsible for most of the supposed experimental confirmations of Zwicky's theory.3 On the other hand, Smckal,4 and Orowan,5 among others, maintain that there is neither theoretical nor experimental evidence to substantiate Zwicky's secondary structure. Lately the subject has been intensively investigated by Buerger,6 one of whose recent papers led to a symposium on mosaic structures.'

Jan 1, 1935

By Alden B. Greninger

The study of mosaic structure of crystals1 has been confined until recently to the field of theoretical physics. Crystallographers, in general, have neglected the subject, although X-ray crystallographers constantly make use of formulas for intensities of X-ray reflection as modified by mosaic structure. Work on mosaic structure has centered chiefly on the task of proving or disproving the secondary-structure theory of Zwicky,² and very little attention has been paid to the visible imperfections of crystals. A. Goetz has been responsible for most of the supposed experimental confirmations of Zwicky's theory.3 On the other hand, Smckal,4 and Orowan,5 among others, maintain that there is neither theoretical nor experimental evidence to substantiate Zwicky's secondary structure. Lately the subject has been intensively investigated by Buerger,6 one of whose recent papers led to a symposium on mosaic structures.'

Jan 1, 1935

By J. W. Axelson

CRUSHING has always been a major operation in the chemical and metallurgical industries, yet little is known about the theory of crushing, and today, the design of crushers is still based almost entirely on empirical knowledge and accumulated practical experience. In view of the increasing national need for the economic working of poorer grades of ores, the lack of a fundamental under- standing of this unit operation hardly presents a satisfactory situation. Basic investigations of crushing have been concerned mainly with three phases of the problem, 1-the mechanism of the fracture process itself, 2- the particle size distribution of the crushed product, and 3-the relationship between the energy input and the amount of new surface produced. Probably adequate information on these phases will be required for a comprehensive understanding of the process of crushing. A bibliography covering these phases will be given as well as a review of the work done in recent years at the University of Minnesota on the relationship between the energy input for crushing and the amount of new surface produced.

Jan 12, 1951

By G. E. Mellor, R. E. Lippoth, T. B. Faddies

The Trixie mine is located in the East Tintic Mining District. Since production began in 1970 over 450 000 tonnes of ore grading 239 grams of silver, 6.9 grams of gold, and 1.2% Cu have been mined from veins in Cambrian Tintic Quartzite. Detailed geologic mapping and extensive sampling are essential for compiling the data base required for efficiently developing and mining known reserves as well as planning exploration and development work. Although the basic techniques used by the geology group at the Trixie were developed many years ago, the reduced activity in underground precious metal mining in the U.S. have made these techniques less familiar to many presently active geologists. The increased activity in precious metals search and exploration again offer cause for the application of these techniques as a prerequisite to efficient exploration, development and production.

Jan 1, 1984

[based on o report by HUBERT E. RISSER] There is a tendency among laymen to relegate America's coal industry to Pennsylvania and West Virginia, completely overlooking-or unaware of- the vast reserves, both those developed and those untapped, situated in the 1.4 million square miles between the Appalachians and the Rockies. At the 1965 AIME Annual Meeting, Hubert E. Risser, Principal Mineral Economist of the Illinois State Geological Survey, presented an interesting picture of the wealth of mineral fuels occurring in that area. In his talk entitled "Trends in Mineral Fuels in the Central United States", Mr. Risser underscored the fact that "more than half of the nation's known reserves of each of the three major fuels-oil, gas and coal-lie within the Central area." The highlights of his speech, with emphasis on the coal situation, are excerpted below.

Jan 6, 1965

By L. J. Trilli

RECENT studies have indicated that there may be considerable difference in the cleanliness of the central pipe cavity of open top ingots. It has been speculated that some of this difference arises becausk of reactions that occur during reheating in the blooming mill soaking pits. In this respect, it has been recognized that an oxide coating or flow of slaggy material in the cavity could inhibit welding during hot rolling and thus reduce the amount of sound product which may be obtained. This note is intended to summarize some observations on the structure of a split ingot top which may be useful in describing a mechanism whereby the shrinkage cavity could be oxidized during reheating. A 221/2x241/2 in., big-end-down, test ingot was secured from a routine production heat. The chemical analysis representing this ingot is as follows: 0.08 pct C, 1.04 pct Mn, 0.062 pct P, 0.315 pct S, and 0.02 pct Si. The deoxidation practice used on the heat from which the experimental ingot was

Jan 1, 1957

By Rollyn P. Jacobson

The town of Pacific, in Jefferson County, Mo., is 27 miles west of St. Louis. Since the area lies entirely on the flood plain of a cut-off meander of the Meramac River, it was considered a likely environment for accumulation of commercial quantities of sand and gravel. Excellent transportation facilities are afforded by two major railways to St. Louis, and ample water supply for washing and separation is assured by the proximity of the river. As a large washing and separation plant was planned, the property was evaluated in detail to justify the high initial expenditure. An intensive testing program using both geophysical and drilling methods was designed and carried out. The prospect was surveyed topographically and a 200-ft grid staked on which electrical resistivity depth profiles were observed at 130 points. The Wenner 4-electrode configuration and earth resistivity apparatus* were used. In all but a few cases, the electrode spacing, A, was increased in increments of 1% ft to a spread of 30 ft and in increments of 3 ft thereafter.

Jan 2, 1955

By Lyall Zickrick

EXPERIMENTS of previous investigations have indicated that calcium-copper alloy, when used as a deoxidizer for molten copper, results in a sound copper casting of good physical and electrical properties. Bradenberg and Wiens1 have obtained successful results in casting sound copper using calcium for deoxidizing. Masing2 has obtained deoxidized copper of high density and high conductivity by use of calcium. Pratt,3 in 1907, patented the use of calcium for the deoxidation and degasification of, copper. Schumacher, Ellis and Eckel 4 in 1929, conducted a series of experiments on deoxidizing copper with calcium. They concluded that so long as there is only a small percentage of residual calcium the mechanical and electrical properties of the copper deoxidized are not impaired; and the deoxidation is thorough. For this investigation, a, copper-calcium alloy high in calcium and 10 variously deoxidized copper ingots were prepared. The investigation concerns itself with the casting properties and structure of these variously deoxidized ingots, their working and annealing characteristics, and the resulting physical and electrical properties of the worked materials.

Jan 1, 1932

By B. G. Langston, R. D. MacDonald, F. M. Stephens

WITH the development of uranium ores that contain substantial amounts of acid-consuming compounds, the alkaline leach has become an attractive method for extraction. Considerable work has been done on both atmospheric and pressure-leaching with aqueous solutions of sodium carbonate and sodium bicarbonate as the lixiviants.1,2,3 For the treatment of uranium-bearing limestones and other high-lime (CaO) ores, the sodium carbonate leach has proven attractive because it avoids the high reagent consumption incurred by the reaction of sulfuric acid with lime. In addition, the corrosion problems with sodium carbonate are negligible as compared with those encountered in the acid-leach system. The sodium carbonate leach, however, does not yield as high an extraction of the uranium as the acid leach and is not attractive for economic reasons when treating ores that are high in sulfates or sulfides.

Jan 9, 1957

By C. Willard Hayes

One of the most productive iron-ore districts of the southern Appalachians lies in the vicinity of Cartersville, in northwestern Georgia, where the ore-deposits are so directly related to the stratigraphic and structural features of the region that a description of its geology possesses economic as well as scientific interest. Stratigraphy.—The area shown on the accompanying map, Fig. 1, occupies the southeastern portion of Bartow county, Georgia. It is about equally divided between the older crystalline and metamorphic rocks which occupy the Piedmont plateau and Appalachian mountains on the east, and the Paleozoic formations which occupy the Appalachian valley on the west. The line separating these two groups of formations enters the mapped area near the northeastern corner, and, pursuing a somewhat irregular diagonal course, leaves it, as shown on the map, near the southwestern corner. This line marks

Jan 1, 1901

By Freeman Bishop

This year the metal mining industry is in for some difficult decisions as the nation struggles to control inflationary pressures resulting from higher production costs and a money-squeeze policy. Re- clouding these problems will be campaign oratory as Congress seeks reelection. Charges will be hurled back and forth between a Republican White House and a Democratic Congress. Inflation and Vietnam will be the big one. Hut pollution i. coming on strong. President Nixon has formed a new Council on Environmental Quality although he already had named a similar unit within his Cabinet six months ago. Both are charged with bringing 1.0 bear all of the Federal Government's talents on the focal points of antipollution measures The biggest task will be to find out how many different "units" are currently mixed up in these efforts.

Jan 1, 1970

By F. R. Morral

HOT-DIPPED heat-treated zinc coatings on sheet steel were examined with X-rays. The phases identified were compared with those listed in the modern literature of the zinc-iron system. The zeta (FeZn13) phase is shown to correspond to the phase found by Schueler (1925) in heat-treated zinc coatings. An investigation was undertaken to determine the phases present in hot-dipped FIG. I.-SYSTEM IRON-ZINC ACCORDING TO J. SCHRAMM.11 heat-treated zinc coatings on steel sheets and wire. This kind of coating on wire was studied some years ago by Schueler1 by microscopic and chemical methods. He reported a new phase, FeZn10. Later, Clark and Stillwell,2 using X-ray crystal analysis, identified a new phase in ordinary galva-nized wire, which was assumed to be the FeZn10 phase.

Jan 1, 1940