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By Walter J. Johnson

The coals in northern Wyoming and Montana are free-burning and non-caking and range from lignite to bituminous C in rank. Strip and underground mining are employed to supply railroad, utility, industrial, and domestic fuel. The market area includes Iowa, Nebraska, Minnesota, North and South Dakotas, Wyoming, Montana, the Pacific Northwest, and western Canada.

Jan 12, 1953

By R. J. De Angelis, J. B. Cohen, A. Nelson

In this note several recent results on twinning in copper shock-loaded with planar shock waves will be presented and the role of the twins in recrystalliza-tion will be discussed. The twinlike markings first observed in shock-loaded copper by smith1 were identified as twins by De Angelis and Cohen.2 This identification has been confirmed by others.3 In Ref. 2 it was also shown that there is an orientation dependence for twinning at low shock pressures, such that twins in a crystal loaded in [lll] form in the rarefaction or tensile wave but in

Jan 1, 1967

By J. O. Whiteley

IT is difficult to give a refining outline that may be followed for any and all combinations of the platinum metals; different combinations require different methods of attack. This paper does not pretend to go into all of the reactions of the metals of the platinum group, but will outline the commercial refining of platinum scrap. TYPICAL PLATINUM SCRAP As a concrete case, let us take 100 oz. of miscellaneous scrap, made up of jewelry scrap, dental scrap and laboratory ware. This lot will contain some platinum, palladium, iridium, ruthenium, rhodium, gold, silver and copper. The first problem is to get all of the metals in solution. If the scrap is principally platinum, palladium and gold, a treatment with aqua regia is the course to pursue; but if the scrap contains alloys high in iridium or ruthenium, aqua regia will act too slowly. In the case in hand, we are going to presume that we have scrap high in iridium and ruthenium, and proceed accordingly.

Jan 1, 1928

By J. R. Finlay

Every business man who has reached the age of forty, or perhaps even thirty, must know from his own experience that there are occasional periods of "good times'' and others of "bad times "-booms and panics. Those who give to business some complexion of science have invented a semiscientific name for these alternations-the business cycle-indicating that it is a normal phenomenon which by its own nature repeats itself. The longer one lives and the more one enlarges his own experience by the study of history, the more of these cycles he knows and the more disposed he becomes to take their recurrence for granted. If these alternations can be put into the category of common- places, why not treat them as such? We are in a sharp depression right now, why worry about it? Is there not a certain average value for business that can be depended upon in spite of depressions? By way of rejoinder one might answer that war is the great commonplace of history, but when we get into one we generally find it worthy of attention. In the present case, many a man has lost two-thirds of his income, and he is extremely nervous about finding it again. The Southern Pacific Railroad earnings have dropped 75 per cent in the past year; Pennsylvania, 60 per cent; United States Steel Corp., about the same. The drop in current earnings is

Jan 1, 1932

By Newell Alford

AT its meeting in the fall of 1937, the Executive Committee of the Coal Division considered the growing scarcity of young engineers entering coal mining with serious intentions. This scarcity was the cause of con-siderable alarm and a committee consisting of C. T. Hayden, E. A. Holbrook, C. E. Lawall and L. E. Young, with the writer as chairman, was appointed to gather factual data on the current trend. A questionnaire1 was designed and mailed to the heads of the 60 mineral technology schools listed by Prof. W. B. Plank in his article in September 1937.2 Replies were received from 46 institutions, not all from heads of coal-mining courses but all from men that at one time or another have had experience with some kind of coal-mining curricula and know current student impressions. Our committee is indebted to all of these gentlemen for their cooperation. Our committee hoped by this means to quickly reach the root of the trouble and make a set of comprehensive recommendations to the Coal Division for relieving the industry immediately from the growing dearth of youth who yearn for coal-mining careers, but the condition is more serious than at first diagnosed. We must now refer the question back to the Coal Division, with the recommendation that the Division get the industry's permission for still another major operation on its frame of mind. In addition to 10-year statistics on the first pay received by graduates in coal mining and other technical work, we requested enrollment data for 20 years from all schools with either mining engineering or mineral technology curricula. Nine leading questions were also plied, as shown in the Appendix. Every one of the answers was significant and inter-esting. Fortunately, we encountered positive frankness that was extremely helpful.

Jan 1, 1938

By Chikaosa Tanimoto

INTRODUCTION The committee on Rock Mechanics, Japanese Society for Civil Engineers, has been discussing 'soft rock engineering in Japan' and presented several papers concerning dam, tunnel, bridge and slope constructions to International Symposium on Weak Rock, Tokyo 1981. This is the summarized paper based on References of Okamoto et a1 (1981), Iida et a1 (1981), Working Group on Tunneling-JSCE (1981), Working Group on Bridge Foundations-JSCE (1951) and Kikuchi et a1 (1981), which can convey general view on engineering experiences with weak rocks in Japan. From the point of view to the origin and/or distinctive physical properties, weak rocks in Japan may be classified into (1) sedimentary, (2) weathered, (3) low welded-pyroclastic and (4) fractured ones. Their typical characteristics are summarized in the following section. Concerning dam foundations on soft rock, several hundreds have already been constructed and, at present, nearly one hundred are under construction or at planning stage. These dams, almost without exception, have some problems such as site selection, material selection for fill-type and concrete dams, design of dam and its foundation, and construction procedures, requiring special ingeneous and cautious measures to cope with the local geotechnical difficult situations. In tunneling, for the decade of 1970s, the number of tunnels in soft rock either completed or under construction was at least 160, including Seikan Tunnel of 53.9 km long, Nakayama Tunnel of 14.8 km long and so on. Most of these tunnels are distributed in the northern half of Mainland, consisting of a basement of Paleozoic strata and Plutonic rocks, overlayed by Neogene Tertiary formations which include large

Jan 1, 1982

By Stanley W. Sundeen

2.3-1. Introduction. The subject-"Preliminary Evaluation of Coal, Metallic and Industrial Mineral Deposits for Surface Mining'-seems at first glance to be definitive and not likely to be misinterpreted. Nevertheless, there are widely divergent opinions as to what is meant by "preliminary" and even as to what is meant by "evaluation." Some definition and qualification is necessary in order to provide a readily recognized basis for discussion. Evaluation evokes the idea of organizing extant data and judging its significance especially in the economic sense. It also may evoke the concept of the physical processes of acquiring the data that will characterize the deposit such as the geologic mapping, drilling, etc. Castle (5) considers that evaluation may embrace psychological aspects wherein human traits as, for example, over optimism might cause the evaluator to overlook obvious project weaknesses. In this chapter, evaluation is discussed primarily from the viewpoint of economically appraising a project from data available at a given point in time. The qualifying adjective "preliminary" is not easily defineable. In fact, some kind of evaluation proceeds, if not continuously, intermittently over the full span of exploration and early stages of development of a deposit. Bailly (1) comments: "Sometimes, before starting exploration in new areas or countries for a given commodity, we establish models to define what minimum combinations of re- coverable grade and tonnage are needed to give the minimum acceptable rate of return established by corporate policy. Then, before starting physical exploration in any target area we try and guesstimate optimistically what best 'geometry-grade-tonnage' can be expected. If these are acceptable in light of above minimum combinations, exploration is started as soon as funds are appropriated for the target area.''

Jan 1, 1968

By R. E. Reed-Hill, W. H. Hartt

The "(3034) " twin lamellae in magnesium have been reexamined using electron microscope replicas. The double twinning sequence (1011)- (1012) for these lamellae has been reconfirmed. Evidence is presented showing that the irrational habit of these twins is probably the direct result of a need to accommodate the second-order twinning shear. This accommodation vesults in both an external shear in the matrix and an internal shear in the lamella. A model is presented which accounts for the experimental obseruations. HCP metals are generally characterized by strong textures in which the basal planes of the grains tend to be aligned parallel to the rolling direction in sheet or plate and to the axis of wires and rods. Since these directions are normally those in which finished products may be subjected to uniaxial tensile stress, these textures effectively place the crystals of magnesium objects in orientations unfavorable to both basal slip and {1012) twinning, the easily activated deformation systems of this metal. However, when magnesium crystals are deformed near room temperature by a tensile stress nearly parallel to the basal plane, another mode of deformation can occur.',2 This is _a double twin which forms first by twinning on {loll), followed by retwinning on (1012). The resulting twin lamellae are of considerable interest. First, they can be responsible for "brittle fracture''; when a tensile stress axis lies in the basal plane, because the reoriented crystal structure of a lamella is well-aligned for slip while the parent crystal is not. Extensive internal deformation may thus occur while the matrix is still almost undeformed. This deformation can produce a ductile rupture running the length of the twin.3 Complete failure of the specimen may then oc-cure by the spreading of cracks from one twin lamella to another, or by the movement of a crack into a grain boundary and then along grain boundaries. Since the the volume fraction of these doubly twinned elements is normally very small, the fracture may be classed as brittle, although the fracture mechanism is, of itself, essentially ductile. It is quite probable that the ductility transition, normally observed4 in magnesium at or slightly Obove room temperature, is closely associated with these second-order twins. The detailed relationship of these twins to fracture in single crystals will be the topic of another paper. The present paper is concerned with a second important aspect: the irrational habit of these double twins that falls close to {3034), or approximately 7 deg away from the primary (10il) twin habit. There is good reason to believe that this habit results directly

Jan 1, 1968

By E. R. Borcherdt

METHODS and equipment are subject to study in the Butte district at all times in order that advantage may be taken of any new developments that might serve to increase efficiency and lower costs. Detailed time studies of each operation involved in the entire mining process have been of invaluable assistance in analyzing the individual operation for possible improvement. In other words, the fact that a practice has been in vogue for many years does not exempt it from change provided an easier and cheaper method can be found. EXPLORATION Ore occurs in the Butte district in such manner that structures must be drifted on, no matter how small or unimportant they appear when intersected by a crosscut. Parallel structures also add to the crosscut requirements. This prospecting work, which formerly was done entirely by drifting and crosscutting, is now being supplemented by diamond drilling, to aid in greatly decreasing the amount of waste. In long-shot prospecting, or in second or third class prospecting, where the chances of developing commercial ore are not very great, diamond drilling is of particular value. In prospecting where chances of encountering commercial ore are certain or where crosscuts can be used later for haulage or ventilation, drilling obviously is not applicable. Improvement in drilling machines and bits has contributed greatly to the present success of diamond drilling. STOPING For many years square-set filled sloping was the principal mining method used in the Butte district. Later timbered and untimbered rill stopes were used, also some horizontal cut-and-fill sloping where both ore and walls were particularly strong. Because of the amount of timber required for square-set stoping, and the relatively low production per scope unit, experiments with horizontal cut-and-fill scopes were begun in ore bodies of which many had fairly weak walls. It was felt that increase in the speed of the stoping operation, followed closely by filling, to avoid weight being produced by permitting ore and walls to remain insufficiently supported over comparatively long periods, would maintain the walls and backs in safe condition without the use of timber and without ore dilution from wall slough. Cycles of drilling, scraping ore, and filling were devised, which have materially increased stope production and decreased timber consumption, so that both stope labor and supply costs were lowered appreciably without materially affecting grade control. In the larger mines of the district, where wide veins favor this stoping method, half of the total production is now being mined by horizontal cut-and-fill stopes (Fig. I). The increase of the filling rate demanded by the increased stoping rate was the greatest obstacle encountered in the accelerated stoping operations. Finally this problem was solved by replacing the time-honored method of transferring filling waste by small cars, which were hoisted or lowered in the auxiliary shaft, by a transfer

Jan 1, 1941

By R. L. Klueh, W. W. Mullins

During the course of a study on the periodic precipitation (Liesegang phenomenon) of water vapor bubbles in solid silver, some interesting observations were made concerning the formation and growth of these bubbles. Under certain conditions it was found that the bubbles which formed in the single crystals led to the formation of large blisters ad cracks, and when poly crystalline specimens were used grain boundary cracking was observed. These two phenomena were examined in some detail, and it was found that an important step in the formation of the blisters and grain boundary cracks was the impingement of neighboring bubbles. DURING the study of Liesegang precipitation in solid silver,' some interesting observations were made concerning the formation and growth of water vapor bubbles. The bubbles were formed by annealing oxygen-saturated silver in hydrogen. Because of the similarity of this phenomenon to the hydrogen embrittlement of tough pitch copper,' it is known in the literature" as the hydrogen embrittlement of silver. In some respects it appears that the hydrogen embrittlement of silver is similar to the processes of hydrogen attack of steel5 and blister formation.' Hydrogen attack results from the high-temperature reaction of hydrogen with dissolved carbon or carbides in the steel to form methane (usually at grain boundaries). Blister formation occurs in steel and other materials as a result of hydrogen produced by corrosion, pickling, and so forth. Because of these similarities, some speculations were made concerning these other processes. EXPERIMENTAL PROCEDURE Water vapor bubbles were formed in 99.999+, 99.99+, and 99.9 pct Ag by annealing in a partial pressure of oxygen (pq) until saturated and then in a partial pressure of hydrogen (pH,). The hydrogen diffuses into the silver and reacts with the dissolved oxygen to form water vapor which precipitates in the form of bubbles. The specimens were then sectioned, silver-plated, mounted in cold-setting plastic, ground and polished through a preliminary polishing, and finally chemically polished.' The bubbles were visible without etching.

Jan 1, 1969

By J. R. Thoenen

THE consensus of opinion in the published literature on. Grecian magnesite is that it has been formed by alteration of the serpentine, which in turn was itself a product, of metamorphism from the original olivine intrusion. The general opinion seems to be that the magnesite was formed by descending waters heavily charged with CO2. Inasmuch as this opinion is held by engineers far better qualified than I to speak authoritatively on this subject, I hesitate to dispute that theory. However, certain occurrences coming under my observation do not, to me at least, seem to-entirely substantiate this theory. LOCATION Most of the Grecian magnesite comes from the Island of Euboea, although more recently some deposits have been opened on the mainland near the City of Saloniki, which prior to the war was Turkish. The island, comprising a state or province in the Greek political structure, is roughly 110 miles long and varies from 10 to 30 miles in width. It lies off the east coast of the Greek peninsula in the AEgean Sea with its long axis extending in a northwest-southeast direction. It is separated from the mainland by a long narrow arm of the sea known as the Atalanti Canal. Chalkis (Halkis), the capital on the west coast of the island, is the northern terminus of a branch of the state-owned railway and is connected with the mainland by a single-span, movable, highway bridge, roughly 150 ft. long.

Jan 1, 1928

By Earl F. Hanson

Fires in heavily timbered mines are disastrous, involving danger to both life and property. Some mines have been completely ruined or so heavily damaged that reopening them would not pay. Though few mines are entirely free from danger of fire, the risk is minimized by proper care and good design of plant. The Tintic Standard mine is at Dividend, Utah, in the famous Tintic mining district, about 60 miles south of Salt Lake City. The development of the mine was begun in 1907 by the late Mr. E. J. Raddatz and his associates. From the beginning, the work was hampered by high rock temperatures and the presence of high concentrations of rock gases such as carbon dioxide and nitrogen. Development work was carried on with great perseverance for nine years, and resulted in the discovery of ore in 1916. The total production of the Tintic Standard mine to Jan. 1, 1936, amounted to 1,664,388 tons of ore, having a gross value of $61,996,719. General Layout of the Mine The No. 2 shaft, which is the main working shaft of the Tintic Standard, is within the main orebody and is connected with the five other shafts. Their respective positions with respect to the No. 2 shaft are as follows: North Lily, 2770 ft. northwest with drift connections on the 700 and 900-ft. levels; No. 3 shaft, 670 ft. east connected through the 700-ft. level; Eureka Standard, 4550 ft. south, connected on the 900-ft. level; No. 1 shaft, 1470 ft. southwest, with connecting drifts on the 900 and 1250-ft. levels; Eureka Lilly, 2000 ft. southwest, with connecting drift and raise through the 1250-ft. level. The Tintic Standard orebody consists essentially of one continuous oreshoot extending from the 600-ft. level to the 1450-ft. level, with a cross-sectional area of approximately 70,000 sq. ft. at both top and bottom, reaching a maximum area of 215,000 sq. ft. between the 1100

Jan 1, 1937

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 Edward Sampson, Allan B. Griggs

Surveying of many holes drilled by the U. S. Bureau of Mines in the Metaline district has shown surprising deviations. The holes start in the Ledbetter slate (Ordovician) and pass into the underlying gently dipping Metaline limestone (Cambrian) at varying depths, locally in excess of 1000 it. All holes start vertical, but one had deflected as much as 35° at a depth of only 300 it. One hole was found to be deflected 70' at a depth of 1000 ft. These deviations were not indicated to the drillers by any action of the rods or machines. Analysis of the survey data in the light of the observed geology indicates that the holes deviate most in the Ledbetter slate and scarcely at all in the Metaline limestone. The upper part of the "limestone'" in most holes is a massive rock strongly altered by hydrothermal action and essentially homogeneous. The slate is only obscurely bedded but has a cleavage, varying from slight to strong, which is unrelated to bedding. Drill holes have deflected to become nearly perpendicular to the cleavage. Several plans and cross sections are submitted showing the behavior of various holes. Introduction The Metaline district of northeastern Washington has received much attention recently and has promise of becoming even more important as a source of zinc than at present. Exploration has been conducted largely by deep diamond drilling, and in the course of this work it was found that holes became seriously deflected. This paper deals with the nature and causes of these deflections. The district lies along the Pend Oreille River in the northeastern corner of Washington, about loo miles north of Spokane, 9 miles from British Columbia, and 15 miles from Idaho. Three mines are now in operation and for a number of years have furnished a considerable production of zinc and lead. The ore contains zinc and lead in a ratio of about 31/2 to I, and occurs in the upper part of the Metaline limestone of Cambrian age, the upper member of which, where unaltered, is a rather pure limestone. This is overlain by Ledbetter slate of Ordovician age. Ore has formed by replacement of limestone, commonly 100 to 200 ft. below the slate, in areas of gentle dip, resulting in extensive tabular ore bodies. In and near ore, limestone has been intensely altered to granular dolomite and fine-grained quartz, which, where it predominates, forms "jasperoid." As part of their war program, the Geological survey and Bureau of Mines of the U. S. Department of Interior have been cooperating in an investigation of the district. The exploration by the Bureau of Mines in 1943 and 1944 was conducted largely by deep diamond drilling in which as much as 1000 ft. or more of Ledbetter slate was penetrated before the ore-bearing Metalin-2 limestone was reached. During the course of this drilling it was found that holes were seriously deflected while traversing the Ledbetter slate.

Jan 1, 1949

By J. B. Austin, R. L. Rickett

MEASUREMENTS Of the rate of decomposition of austenite at constant temperature are commonly represented by plotting the percentage transformed on linear coordinates against time on either a linear or a logarithmic scale, a method that yields a curve that in shape resembles an integral sign (Fig. 1). A graph of this kind is not always convenient because extrapolation to the beginning or end of the transformation, or even interpolation, may be uncertain unless there are a large number of observations, which seldom happens; furthermore, the degree of consistency of a set of measurements is difficult to judge from such a curve. It is desirable therefore to find some mode of plotting, or even better to find a standard variety of graph paper, that gives a straight line instead of the integral shape. The straight line has many advantages; the number of readings required to fix the position of the curve is greatly reduced, interpolation is easy and rapid, extrapolation can be carried out with greater confidence and, finally, the consistency of the measurements is readily estimated from the scatter of the points. The last advantage is particularly valuable when the data are obtained by direct microscopic examination alone, because they are influenced by the skill of the observer in estimating the relative size of areas, possibly also by undetected inhomogeneity of the specimen. A search for ways of representing the observations as a straight line yielded two methods which are described in this paper. The paper also includes an account of some interesting relations brought to light in applying these methods to the available experimental data. Usually the best way to derive such a method of plotting is to base it on established principles of chemistry and physics, as has been done, for example, for the temperature variation of the equilibrium constant of a chemical reaction. But so little is known of the mechanism of the decomposition of austenite, and so little is available in the way of well established background for changes of this kind, that it is simpler to rely upon purely empirical means. The general plan therefore is to study existing data with a view to finding some function of the direct observations that will

Jan 1, 1938

By T. R. Graham, R. S. Dean. J. R. Long

Although considerable information has been published concerning manganese additions to the aluminum bronzes, these data refer principally to the two-phase alloys containing 8 to II pet aluminum, with some incidental information on the single-phase alpha solid solution alloys. Straussl gives an excellent review of the literature on aluminum bronzes up to 1927 and a bulletin2 of the Copper Development Association brings the bibliography up to 1938. The most extensive work on manganese addition is that of Rosenhain and Lantsberry,3 who investigated alloys ranging up to 10 pct aluminum and up to 10 pct manganese, and presented data on the physical properties of sand-cast, chill-cast, and several wrought alloys. The greater portion of the work, however, concerns alloys ranging from 7 to 10 pct aluminum in the cast condition and sheds little light on the properties of wrought single-phase alloys. Corson4 notes that alloys containing 10 pct manganese and 4 pct aluminum are not hardenable by heat-treatment, while one with 15 pct manganese and 5 pct aluminum can be hardened, but he gives no tensile data on it. In fact, no systematic study of the properties of single-phase wrought alloys containing substantial amounts of manganese has been reported. It should also be noted that most of the investigators worked with alloys containing significant amounts of iron and silicon, and that these impurities, whether intentionally added or accrued from the raw materials used in the preparation of the alloys, may be expected to have a direct bearing on the resultant properties. In the work on alloys made with electrolytic manganese, the Bureau of Mines has undertaken an investigation of the copper-manganese-aluminum system for the purpose of establishing the constitution and properties of high-purity alloys. In a recent paper6 the authors reported a metallographic investigation of the alpha solid solution area and the adjoining fields of the copper-manganese-aluminum system up to 50 pct manganese. This study established the alpha-phase boundaries at 50" temperature levels from 400' to 850°C. It was found that the addition of manganese to copper-aluminum alloys decreases the solub%ty of aluminum in the alpha phase (Fig I), curving the boundary toward the copper-manganese base line. The greatest change occurs in the first 20 to 25 pct manganese, which decreases the solubility of aluminum to approximately 4 pct. With larger amounts of manganese the alpha boundary tends to parallel the copper-manganese binary. At 13oo'F and higher,

Jan 1, 1947

By R. S. Dean. J. R. Long, T. R. Graham

Although considerable information has been published concerning manganese additions to the aluminum bronzes, these data refer principally to the two-phase alloys containing 8 to II pet aluminum, with some incidental information on the single-phase alpha solid solution alloys. Straussl gives an excellent review of the literature on aluminum bronzes up to 1927 and a bulletin2 of the Copper Development Association brings the bibliography up to 1938. The most extensive work on manganese addition is that of Rosenhain and Lantsberry,3 who investigated alloys ranging up to 10 pct aluminum and up to 10 pct manganese, and presented data on the physical properties of sand-cast, chill-cast, and several wrought alloys. The greater portion of the work, however, concerns alloys ranging from 7 to 10 pct aluminum in the cast condition and sheds little light on the properties of wrought single-phase alloys. Corson4 notes that alloys containing 10 pct manganese and 4 pct aluminum are not hardenable by heat-treatment, while one with 15 pct manganese and 5 pct aluminum can be hardened, but he gives no tensile data on it. In fact, no systematic study of the properties of single-phase wrought alloys containing substantial amounts of manganese has been reported. It should also be noted that most of the investigators worked with alloys containing significant amounts of iron and silicon, and that these impurities, whether intentionally added or accrued from the raw materials used in the preparation of the alloys, may be expected to have a direct bearing on the resultant properties. In the work on alloys made with electrolytic manganese, the Bureau of Mines has undertaken an investigation of the copper-manganese-aluminum system for the purpose of establishing the constitution and properties of high-purity alloys. In a recent paper6 the authors reported a metallographic investigation of the alpha solid solution area and the adjoining fields of the copper-manganese-aluminum system up to 50 pct manganese. This study established the alpha-phase boundaries at 50" temperature levels from 400' to 850°C. It was found that the addition of manganese to copper-aluminum alloys decreases the solub%ty of aluminum in the alpha phase (Fig I), curving the boundary toward the copper-manganese base line. The greatest change occurs in the first 20 to 25 pct manganese, which decreases the solubility of aluminum to approximately 4 pct. With larger amounts of manganese the alpha boundary tends to parallel the copper-manganese binary. At 13oo'F and higher,

Jan 1, 1947

By Walter O. Snelling

In the course of some experiments more than five years ago, made for a totally different purpose than the investigation of the oil used, I placed a small quantity of a transparent yellow lubricating oil in a bomb-like vessel and heated it to a relatively high temperature. At the end of the experiment I removed the oil from the vessel and was amazed to find that instead of bearing any resemblance to the oil which I had put in, it now had the appearance of ordinary crude oil. The green color by reflected light and the rich red-brown by transmitted light were so unmistakable as to at once lead to further investigation. I subjected the material to fractional distillation, and the surprise which I experienced at the appearance of the oil, changed to amazement when I found that it yielded, on distillation, 15 per cent. of gasoline and 30 per cent. of burning oil, and that its constitution resembled crude oil quite as much as did its appearance. Furthermore, the gasoline and kerosene distillates which it yielded were of a clear water-white color, entirely without treatment with acid or alkali, and were entirely free from the odor familiar in "cracked" petroleum distillates. The result of this experiment was quite too remarkable to be credited without further confirmation, and I at once filled the vessel with some of the same oil that I had used before, and again heated to about the same temperature that I had previously used, and for the same period of time. Upon opening the vessel and removing the contents I found, not the material resembling crude oil that I had obtained before, but apparently only the same oil that I had put in, somewhat darkened in color, but nevertheless far different in appearance from the material obtained in the previous experiment. Evidently some condition existed in the first experiment that had not existed in the second test, and here began a series of tests in which I sought by the change of one variable after another to arrive at the identical conditions which must have existed in the first experiment. Only the fact that the bottle of heavy oil used in the first test was still in its place,

Jan 1, 1915

By John Peperakis, James Quigley

IN 1950 Kaiser Steel Corp. acquired control of the Utah Fuel Co., a pioneer Utah coal concern owning large reserves of high volatile coking coal near Sunnyside, Utah, and large reserves of coal elsewhere in Utah and Colorado. Kaiser Steel later disposed of the noncoking quality reserves included in the property and over the past six years has developed a group of three fully modernized mines and a central preparation plant at Sunnyside. This plant is geared to furnish 1.6 million tons per year of low ash coking coal to the byproduct coke ovens at its steel plant at Fontana, Calif., and to its beehive oven coking plant at Sunnyside. General Problems: Topographic and physical conditions under which Utah coals are found differ from those in most bituminous coal districts of the eastern and central states. Utah coal seams lie under deeper cover, generally at steeper pitches; consider- able distances are burned along the outcrop and back from the surface of the outcrop. Usually the coal seams lie high up on escarpments, accessible only through deep narrow canyons or long rock tunnels and tramways. The topography at Sunnyside is particularly rough, with great changes in cover over the coal in relatively short horizontal distances. This is due to the cliff-making sandstones of the cretaceous Mesa Verde group, the coal-bearing measures being in the Blackhawk formation. The thick massive Castle Gate sandstone of the Prince River formation overlies the coal-bearing rocks and is suspected to be the chief cause of roof control problems.

Jan 10, 1957

By Ralph W. Bailey, William B. Price

During the past three or four years, the fabricators of silicon-bronze alloys have endeavored to induce users of phosphor bronze to use instead the silicon-bronze alloys, claiming that the silicon bronzes are superior to the phosphor bronzes for switches and springs, or where high fatigue resistance is desired. This paper gives the results of tests comparing several phosphor bronzes with a 3 per cent silicon bronze and a copper-nickel-tin alloy (Adnic), all processed by the Scovill Manufacturing Co. So far as the authors are aware, sheet-metal fatigue tests have not been made on any of the alloys included in this report, except on one phosphor bronze, material C, Table 1, which was tested by Townsend and Greenall1. Endurance Limit The majority of fatigue tests are designed to determine the endurance limit of a material. The number of repetitions of stress that will serve to establish an endurance limit varies with different materials. For ferrous materials, H. F. Moore2 has shown that stresses that do not cause failure up to 10,000,000 stress cycles will not cause failure up to 100,000,000 (and sometimes to 1,000,000,000) cycles. Thus an endurance limit for ferrous materials can be determined with a minimum of 10,000,000 stress cycles. For nonferrous materials, no such generalization holds. R. R. Moore3 has shown that for manganese bronze and elektron metal, 13,000,000 and 28,000,000 cycles, respectively, will serve to determine an endurance limit, while certain duralumin specimens gave no indications of having reached an endurance limit up to 400,000,000 stress cycles. J. B. Johnson6 showed that an endurance limit for duralumin was not found by tests running up to 500,000,000 cycles. H. F. Moore2

Jan 1, 1937