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By John W. Langley

In the summer of 1888 it was the fortune of the writer to present the subject of the desirability of establishing a set of samples of steel, which should be analyzed with extreme care, in order that they might become standards to which scientific and commercial analyses of iron and steel could be subsequently referred; also, that greater uniformity in the results of analyses might be brought about, since these standards would bear towards analytical methods somewhat the position which the original units of weight and length, the gramme and meter, or the pound and yard, preserved in Paris, London, and Washington, do to the mechanical arts. The plan met with hearty co-operation, with the result that com mittees were appointed in Sweden, Germany, France, England, and America, to receive the material and to see that the necessary au alyses were executed. In England, the British Association for the Advancement of Science appointed a committee, which subsequently published a plan

Jan 1, 1891

By John Branner

FIVE of the geologic horizons that yield oil in other parts of the world are represented in Brazil; namely, the Devonian, Carboniferous, Permian, Cretaceous, and Tertiary. Thus far, the first two have shown no, evidences of being oil bearing within Brazilian territory. Not enough exploring has been done to permit trustworthy comparisons of the relative importance of the Permian, Cretaceous, and Tertiary as oil-bearing horizons in this country. The most important, indeed almost the only, information available relates to the locations of the areas and to the structural features of the several horizons. The theories regarding the physical conditions under which these rocks were laid down, however, I regard of the utmost importance. PERMIAN Rocks of Permian age cover an enormous area in Brazil, extending from Rio Grande do Sul to Maranhão on the north, and to Matto Grosso on the west. These Permian rocks in many places are known to include oil-bearing shales and in some locations contain small veins of gilsonite. The geologic map of Brazil shows that the Permian area is widely distributed, but there is considerable doubt about 'the origin of some of the rocks:. Some of the lower Permian beds in southern Brazil contain marine fossils, but in Minas no fossils have as yet been found in them, and in Bahia, at only one locality have a few Permian plants been found. Indications of oil have been found in the states of São-Paulo, Paraná, and elsewhere farther south, but wells drilled in the Permian of São Paulo near the Morro do Bofete did not find oil. One well has been started, by the Brazilian government, in the Permian of Paraná near Marechal Mallet, close to latitude 26° south, but thus far oil has not been found.

Jan 6, 1922

By John C. Branner

Five of the geologic horizons that yield oil in other parts of the world are represented in Brazil; namely, the Devonian, Carboniferous, Permian, Cretaceous, and Tertiary. Thus far, the first two have shown no evidences of being oil bearing within Brazilian territory. Not enough exploring has been done to permit trustworthy comparisons of the relative importance of the Permian, Cretaceous, and Tertiary as oil-bearing horizons in this country. The most important, indeed almost the only, information available relates to the locations of the areas and to the structural features of the several horizons. The theories regarding the physical conditions under which these rocks were laid down, however, I regard of the utmost importance. Permian Rocks of Permian age cover an enormous area in Brazil, extending from Rio Grande do Sul to Maranhao on the north, and to Matto Grosso on the west. These Permian rocks in many places are known to include oil-bearing shales and in some locations contain small veins of gilsonite. The geologic map of Brazil shows that the Permian area is widely distributed, but there is considerable doubt about the origin of some of the rocks. Some of the lower Permian beds in southern Brazil contain marine fossils, but in Minas no fossils have as yet been found in them, and in Bahia, at only one locality have a few Permian plants been found. Indications of oil have been found in the states of Sa0 Paulo, Parana, and elsewhere farther south, but wells drilled in the Permian of SaO Paulo near the Morro do Bofete did not find oil. One well has been started, by the Brazilian Government, in the Permian of Parana near Marechal Mallet, close to latitude 26" south, but thus far oil has not been found.

Jan 1, 1923

By John C. Branner

Five of the geologic horizons that yield oil in other parts of the world are represented in Brazil; namely, the Devonian, Carboniferous, Permian, Cretaceous, and Tertiary. Thus far, the first two have shown no evidences of being oil bearing within Brazilian territory. Not enough exploring has been done to permit trustworthy comparisons of the relative importance of the Permian, Cretaceous, and Tertiary as oil-bearing horizons in this country. The most important, indeed almost the only, information available relates to the locations of the areas and to the structural features of the several horizons. The theories regarding the physical conditions under which these rocks were laid down, however, I regard of the utmost importance. Permian Rocks of Permian age cover an enormous area in Brazil, extending from Rio Grande do Sul to Maranhao on the north, and to Matto Grosso on the west. These Permian rocks in many places are known to include oil-bearing shales and in some locations contain small veins of gilsonite. The geologic map of Brazil shows that the Permian area is widely distributed, but there is considerable doubt about the origin of some of the rocks. Some of the lower Permian beds in southern Brazil contain marine fossils, but in Minas no fossils have as yet been found in them, and in Bahia, at only one locality have a few Permian plants been found. Indications of oil have been found in the states of Sa0 Paulo, Parana, and elsewhere farther south, but wells drilled in the Permian of SaO Paulo near the Morro do Bofete did not find oil. One well has been started, by the Brazilian Government, in the Permian of Parana near Marechal Mallet, close to latitude 26" south, but thus far oil has not been found.

Jan 1, 1923

By Carl Heinrich

I HAVE read with particular interest that portion of the discussion by Anton Eilers referring to the high-lime (and also high-alumina) slags made by August Raht in 1881, while smelting the Horn Silver ores at Franklin, Utah. The two analyses of such slags, furnished by Mr. Raht to Mr. Eilers are: Horn Silver Slags Oxygen(b) Oxygen(b) Average of I and. II Slag I percentage Slag II percentage Oxygen Si02 33.9 18.1 .35.0 18.7 34.50 18.40 FeO 26.8 6.0 25.4 5.7 26.10 5.80 CaO 26.1 7.5 24.9 7.1 25.50 7.30 BaO 3.2 (a) 0.3 3.2 0.3 3.20 0.30 A1203 10.8 5.1 9.3 4.4. 10.05 4.75 100.8 37.0 97.8 36.2

Jan 10, 1916

Jan 1, 1970

By James R. Aggson, John C. Curran

In a cooperative research effort, the US Bureau of Mines Denver Mining Research Center and the Pittston Co. investigated floor heave ground control problems that have plagued underground coal mining of the Beckley coalbed in southern West Virginia. Floor heave is accompanied by a redistribution of stresses and loads that are associated with underground openings, causing roof and pillar problems. The floor and roof analysis techniques that were used in the USBM/Pittston investigation may have a wide range of applicability in the mining industry. Recommended orientations and geometries for mining operations are directed at floor problems, but may also enhance roof stability.

Jan 1, 1980

By Allen H. Rogers

THE need for coordinated effort on public problem by engineers has long been felt. Early in June there will assemble in Washington a conference composed of delegates from all the engineering organizations in the country. The call for this conference is issued by the Joint Conference , Committee of the four national societies as the completion of its work on the organization of a congress composed of delegates representing all the engineering organizations of the United States. The plan for this confederation was presented at a joint meeting of the administrative boards of the national founder societies on Jan. 23, 1920; and was unanimously approved in principle by that meeting. The work of the committee since that date has consisted in drafting a constitution of the organization to be presented at the conference for discussion and, after such amendments as may be adopted, acceptance.

Jan 1, 1920

By J. Kent Smith

VANADIUM is generally spoken of as a rare element; but, even in the light of our resources as known a couple of years ago, this description could be accepted in a qualified sense only. In fact, vanadium is very widely distributed, being a constituent of most clays, while even caustic soda has been shown to contain almost regularly a minute proportion of it, although the quantity in each case is so small as to render impracticable the extraction of the metal there from with profit. The opening-up of a large deposit of vanadium sulphide ore in South America has put a new phase on the commercial outlook of vanadium, the technical value of which for the improvement of steel has been proved by rigorous scientific investigation.

Sep 1, 1907

By Keats, J. L.

IN THE literature on the elimination of metalloids in basic open-hearth practice, there are a great many heats recorded in which excellent data on changes in slag and metal composition during refining are given, but in almost all of these heats either temperature data or weights and analysis of charge are unrecorded and observations on the physical charac- teristics of the slag are almost always lacking. With these points in mind, a test heat was made in which as complete as data possible on all the factors that affect the elimination of metalloids were obtained.

Jan 1, 1957

By H. R. Stahl

FIVE mills are operated in Southeast Missouri by the St. Joseph Lead Co.; these have a total rated capacity of 24,300 tons per day divided as follows: Federal, 12,000 tons; Leadwood, 4800 tons; Desloge, 3600 tons; Bonne Terre, 2400 tons; and Mine La Motte, 1500 tons. These concentrators are similar in a general way, differing mainly in size and type of equipment and in minor variations in flow sheet. No attempt is made rigidly to standardize procedure in the various mills in spite of a general similarity in the ores. Each mill may be regarded as a separate laboratory in which new ideas and changes may be tried. A generalized description of the process is given, noting important differences in procedure at the various plants. The concentration process may be divided into five main stages: dry crushing, wet grinding, desliming and classification, tabling, and flotation.

Jan 1, 1947

By W. J. Babyak

The habit planes for hydride precipitation in large grains of alpha zirconium and Zircaloy-4 were determined in specimens containing 161 and 136 ppm hydrogen, respectively. In zirconium, the hydride platelets precipitated on various pyramidal planes inclined to the basal plane at angles ranging from 10 to 50 deg and 75 to 90 deg. Hydrides were most frequent at inclinations of about 20 deg and 90 deg. In Zircaloy-4, hydride plates were inclined to the basal plane at angles vanging from 5 to 25 deg with the predominant inclinatioiz equal to 12 deg; no platelets were found near the prism plane position. In both zircoinium and Zir-caloy-4, hydrides were principally, but not exclusively, parallel to (1011) type planes. When the Zircaloy-4 gmins were subjected to tension stresses of 12,100 psi and 19,400 psi during hydride precipitation, the hydride habit was unchanged except that precipitation favored those habit planes which were inore nearly perpendicular to the stress direction. The stress-orientatioiz effect increased with the magnitude of the stress. THE hydride habit plane in a zirconium has been determined by several investigators. Langeron and Lehr1 in 1956 found platelets parallel to (1010) slip planes. In 1962, Westlake and Fisher2 confirmed these findings and showed that hydride precipitation on twin planes, as reported by Kunz and Bibb,3 was probably due to incomplete removal of worked metal from specimen surfaces. Secondary habit planes, ( 1011) and (1015), were also found by Westlake and Fisher under particular charging conditions where a hydride layer may have existed at the hydrogenation temperature. Most recently, walters4 and westlake5 again observed the (1010) habit exclusively in zirconium. Louthan and hgermans have reported that hydrides precipitate on various ( 101l ) and (112l) planes positioned 31.5 to 90 deg to the basal plane in Zircaloy-2. The present investigation was concerned with the hydride habit in Zircaloy-4 in relation to that in zirconium and the possible change in habit when precipitation occurs under stress. The latter consideration was prompted by the stress-orientation phenomenon originally reported by Marshall and Louthan.7, 8 I) EXPERIMENTAL Materials and Specimens. Chemical analyses of all materials are given in Table I. The zirconium specimen was a 1 by 4 in. section cut from wrought crystal bar that was hot-rolled at 790°C to 0.300 in. and cold-rolled to a final thickness of 0.095 in. All surfaces were mechanically polished and then chemically polished with a solution of H2O, HNO3, and HF (10:10:l by volume) prior to annealing. Grains as long as 0.25 in. were grown by thermally cycling the specimen three times (in 10-5 mm Hg vacuum) between 825" and 1000°C at approximately 125°C per hr. The specimen was isothermally annealed at 825°C for 24, 40, and 120 hr after each cy-

Jan 1, 1968

By R. R. Vandervoort

The creep behavior of Nb(Cb), Ta, Mo, and W was determined under conditions of constant atomic dif-fzisivity, constant stress to elastic modulus ratio, and nearly equivalent grain size, and the steady-state creep rates obtained from these tests were correlated with calculated stacking fault energies for the metals. These results, in conjunction with similar data for several fccMetals,13 suggest that stacking fault energy may influence the creep strength ofbcc metals. The interrelationship between steady-state creep rate, subgrain size, and stacking fault energy was examined. It was found that the subgrain size for a given creep stress, increased as stacking fault energy increased, but that this relationship did not cormpletely account for the effect of stacking fault energy on creep rate. The crystallography and energetics of stacking fault formation in bcc metals has been discussed by a num-ber of authors,1-5 and impurity stabilized stacking faults on (112) planes have been observed in Nb,6,7 w,8,9 Fe,] and V" by transmission electron microscopy. However, a crucial question is whether or not stack-ing faults influence the mechanical strength of bcc metals. Potentially, stacking faults could increase strength by reducing the mobility of the partial dis-locations bounding the fault, by acting as barriers to slip dislocations, and by retarding the climb of dislo-cations during high-temperature deformation. The objective of this study was to seek a correlation be-tween creep strength and stacking fault energy for several bcc metals; namely, Nb, Ta, Mo, and W. The creep behavior of most polycrystalline metals and alloys at high temperatures and moderate stresses can be described by the following relation:11,12 im=Af(s) where i, = minimum creep rate, A = constant, j(s) = a function involving metallurgical structure, a = applied stress, E = average elastic modulus at the test tempera-ture, w = constant (equal to 5 for most pure metals), D = diffusion coefficient. One factor in the structure function F(s) which sig- R. R. VANDERVOORT, Member AlME is Research Metallurgist, Process and Materials Development Division, Chemistry Department, Lawrence Radiation Laboratory, University of California, Livermore, Calif. Manuscript submitted February 28, 1969. IMD nificantly affects the creep resistance of fcc metals is stacking fault energy, and creep rate has been shown to vary directly with stacking fault energy to the 3.5 power." In the latter investigation, four fcc metals of widely different stacking fault energies (Ag, Cu, Ni, and Al) were creep tested at a constant stress to modulus ratio of 1.21 x 10-4, at a constant diffusivity of 2.7 x 10-12 sq cm per sec, and at nearly equivalent grain sizes of about 0.7 mm. The creep data were then correlated with stacking fault energies. In the present study, a similar procedure was followed. All materials used in this work were consolidated by powder metallurgy techniques. Impurity contents in the as-received materials are listed in Table I. Chemical analyses showed that no measurable contamination of the test specimens occurred during pretest annealing treatments or creep testing. Specimens with a gage section 0.75 by 0.125 by 0.050 in. were creep tested in tension in a vacuum of less than 10-9 torr. Deformation at temperature was measured by tracking fiducial marks on the gage section of the specimen with an optical comparator. Optical deformation measurements also permitted observation of the macroscopic characteristics of the deformation Table I. Typical Specimen Impurity Content, ppm Nb Ta Mo W C 45 10 155 6 O 185 30 4 10 N 30 6 3 2 H 5 I 1 <1 als 3 10 2 15 Ca <5 I3 5 Cr 5 <3 10 <5 Cu 10 50 2 15 Fc 10 10 150 35 Ni 2 150 20 <5 Si <I0 1 3 <10 Ta 100 Ti 10 8 1 Zi 15 50 1 3 Table II. Test Conditions for Constant Stress-Modulus Ratio of 6 X 10.&apos; and Constant Diffusivity of 2.7 X 10-12 sq cm per see, and Grain Size Values for the Given Pretest Annealing Treatments Literature references Pretest Annealing for E and D Treatment Stress, Temperature, ___"&apos;Values__ Grain Tempera-Metal psi "C E D Size, mm ture, .C Time hr Nb 745 1525 14 15 to 17 0.83 1650 I Ta 1220 1770 18 19.20 O.91 1800 I Mo 1975 1630 18 21 0.77 2200 I W 2140 2265 18 22 040 2400 5

Jan 1, 1970

Seattle offered sunny, dry weather to about 2500 mining men who assembled September 10 to 14 for the 1961 American Mining Congress. The impact of snappy sessions on national mineral policy, state of the industry and foreign competition (to name only a few) was somewhat overshadowed by enthusiasm of conventioners for salmon fishing. This lordly fish, which mysteriously runs to its hatching place to spawn and die at this time of year, was not cooperating with the anglers in Puget Sound. However, this did not prevent consuming ample amounts of the deliciously prepared Quinault salmon at the "Potlatch" celebration.

Jan 10, 1961

By Spencer S. Shannon

This chapter is concerned with the uses, geology, exploration, evaluation, preparation for markets, and future of 90thorium and 39yttrium, along with 14 rare-earth elements. The rare-earth metals or lanthanides were divided into three categories by Berzelius. The cerium subgroup is comprised of 57lanthanum, 58cerium, 59praseodymium, 60neodymium, and 62samarium. 61Promethium does not occur naturally. The terbium subgroup includes 63europium, 64gadolinium, and 65terbium. The remaining lanthanides are placed in the yttrium subgroup. Strictly speaking, yttrium is not a rare earth. Because the properties of yttrium resemble those of heavy rare earths, its name has been used as a designating adjective. The yttrium subgroup includes 66dysprosium, 67holmium, 68erbium, 69thulium, 70ytterbium, and 67lutetium. Rare-earth elements, especially those of the same subgroup, tend to occur together rather than in discrete minerals.

Jan 1, 1975

By Carl Zapffe

THE object of the Bradley process is to free manganese oxide from its associated gangue and separate the contained iron oxide by dissolving the manganese and precipitating it from the solution. &apos;The fundamental features of the process are : making. both 1 a manganese ore and an iron ore; effecting a separation of manganese .and. iron by means of selective roasting; leaching- the manganese from the roasted ore by using &apos; ammonium sulfate; precipitating the manganese by using the ammonia gas generated during leaching; fixing the precipitate by oxidizing with air; breaking down and reforming the ammonium sulfate, so that daily very little additional ammonium sulfate beyond that originally charged into the system is required; washing the manganese precipitate and the iron-silica residue and evaporating the liquor to conserve the dissolved salts in the moistures of these two products and &apos;to reduce the sulfur content,; drying the precipitates; magnetic wet-concentration of the iron-silica residue; sinteriny the manganese-and .the&apos; iron-concentrates.

Jan 1, 1929

By Harold Margolin

The Ti-Al system certainly merits the investigative attention it has been receiving and this latest contribution by Blackburn is therefore to be welcomed. The titanium-rich end of the phase diagram shown here, as well as the diagram by crossley,17 Clark et a1.,18 and Tsujimoto and Adachi,29 reveal no other intermediate phase than Ti3A1, although a previous work by Ence and Margolin20 had reported an additional intermediate phase. Since then, Buerger Precession pictures of single crystals of 10.5, 11.5, and 12.5 wt pct A1 were made at New York university21 and the extinctions were found to be typical of a D6h a Ti structure. Some superlat-tice spots and/or streaks suggesting the presence of an Mg3Cd structure, i.e., Ti3Al, were also found. Since these specimens had been quenched from the y region20 and had revealed a Ti, it was concludedz1 that y does not exist and the structures interpreted as m + y could not be so considered. The absence of normal two-phase behavior in these structures had been indicated in the paper. Accordingly, the two-phase region y + 6 becomes a + Ti3Al and there is some agreement between the results of Blackburn and of Ence and Margolin20 as to both shape and existence above 900°C of an a + Ti3Al field. Crossley 17 proposed that Ti3Al is a line compound which decomposes congruently at 900°C. It is difficult to discount entirely the fact that clear two-phase structures, varying in amount with position in the two-phase field, could be detected above 900°C by Ence and Margolin.20 Precipitation during quenching could not have been so regular and the twin-phase syndrome17 does not apply. The heat treatment and quenching technique was essentially the same as was used by Crossley, whereas Blackburn, who used a rapid quenching procedure, also showed a two-phase a + Ti3A1 field above 900°C. If the two-phase field exists above 900° C, it is easy to picture a two-phase field which could account for the data of Crossley below 900°C without invoking a line compound existence of Ti3A1. All that would be necessary would be an 0 + Ti3Al/Ti3Al boundary which curved sharply to higher aluminum contents below 900° C. It is clear that the controversy must be solved by techniques which obtain data at elevated temperatures without quenching. It is conceivable that the difference in width of the a + Ti3N fields reported by Blackburn and by Ence and Margolin is due to the longer annealing times used by the latter investigators. The criterion for establishment of equilibrium in our work20 was the

Jan 1, 1969

By Charles W. Schwartz, Subash Kolluru

INTRODUCTION Creep of rock in situ, like most rock mass behavior, will be largely governed by the behavior of the natural discontinuities -- bedding planes, faults, and joints, in particular, Several past studies have investigated various aspects of the time-dependent deformation of rock discontinuities; examples include Amadei and Curran (1980), Engelder and Scholz (1976), Johnson (1975), Kaiser and Morgenstern (1979), Solberg et al. (1978), and Wawersik (1974). These studies have provided much insight into the general phenomenon, but they have also produced some inconsistent conclusions and left many unanswered questions. This paper will attempt to shed some light on one of these questions: What is the influence of stress level on the creep of unfilled rock joints? The discussion will follow a two-part approach to the problem: (1) laboratory creep experiments on small scale jointed specimens, (2) a simple theoretical mechanism to explain, at least in qualitative terms, some of the results from the experimental program. EXPERIMENTAL PROGRAM Uniaxial creep tests were conducted on intact and jointed samples of a specially formulated gypsum plaster "synthetic rock." Synthetic rock materials have several advantages over natural rock for long-term creep testing: (a) higher creep rates, (b) lower strength and therefore lower loading requirements, (c) simpler specimen preparation, and (d) more controlled and consistent properties. Gypsum based plasters have been used previously in studies of short-term strength and deformability of jointed samples (Patton, 1966; Einstein and Hirschfeld, 1973). Furthermore, Williams and Elizzi (1977) demonstrated that natural gypsum, at least, creeps in a manner similar to that of most other creep-susceptible natural rocks.

Jan 1, 1982

By John Wellington Finch

INVESTIGATIONS by the Bureau of Mines of deposits containing strategic minerals were authorized by what has become known as the Strategic Materials Act (Public No. 117, 76th Congress, Chapter 190. 1st Session). A later act providing an appropriation for the first of four years through which the investigations are to be conducted was signed on Aug. 9, 1939. No time has since been lost as seven field projects already are being vigorously prosecuted, and two others no doubt soon will be in course of execution. Project engineers were at their stations within two days after funds had been made available. Crews have been hired; equipment and supplies have been purchased; 5 bids for diamond drilling have been obtained and the drilling has started base camps have been established: ground has been cleared; and several thousand feet of trenching, test-pitting, and sampling have already been done. At the Reno Experiment Station of the Bureau, a special metallurgical laboratory has been provided to make assays, analyses, and tests upon samples of ores from all projects under investigation.

Jan 1, 1939

By D. J. McAdam

Results of investigation of corrosion-fatigue of metals at the U. S. Naval Engineering Experiment Station, Annapolis, Md., have been discussed by the writer in several recent paper~.1,2,3,4 In those papers references were also given to the work of Haigh in 1917.= Efforts by the writer to obtain a better understanding of some of the factors involved in corrosion-fatigue finally developed into a general investigation of the effect of time and cyclic stress on corrosion of metals. Corrosion-fatigue of Metals As described in the papers mentioned, rotating-cantilever specimens, conically tapered so that the stress is nearly uniform over a length of about 1.5 in., were subjected to simultaneous fatigue and corrosion. For this purpose a stream of water was diagonally applied so as to sweep the specimen from the outer to the inner fillet and surround the stressed surface with water. The fresh water is a calcium carbonate water, the composition of which has been given in a previous paper.2 The salt water is Severn River water having a saline content about one-third that of sea water. The previous papers described results obtained with ferrous and non-ferrous metals. The experiments showed that even slight corrosion simultaneous with fatigue may cause failure at nominal stresses far