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By George F. Kunz

Jan 1, 1902

By G. R. Love, M. L. Picklesimer

Aboue 950°C the Nb-Zr system consists of a completely miscible bcc solid solution, commonly called the phase. Between 950 and 600°C, and between 20 and 85 pct Nb, the phase deconlposes, after sunciently long times, into two bcc solid solutions. The pct Zr alloys are conveniently descibecl with T-T-T (time-temperature-transformation) curves having a nose at about 2 hr at 700°C. The reaction rate varies only slowly with zirconium content and negligibly with oxygen contanzination; it is speeded up by a factor of 10 to 15 by 90 pct cold ulork and slowed dou by n factor oj 10 to 30 by a two-hundrecljold increase in grain size. Nb-r alloys with compositions between 40 and 85 pct Nb have been the basis for the majority of commercially important superconducting materials. In part because of their commercial promise, more is known about these alloys than about most other high-field superconducting materials. At the same time, there is considerable disputed or incomplete metallurgical information. For example, although Rogers and tkins&apos; indicate a monotectoid reaction at approximately 600°C and a two-phase 01 + 0, field extending between 20 and 85 pct Nb and to a maximum of 95OGC, erhout&apos; has reported that this entire region would be a single homogeneous B were it not for oxygen contamination. Again, although it has been shown that relatively short-time heat treatments in the vicinity of 700CZ significantly improve the ability of short wire samples to carry high currents in high magnetic fields at 4.2K, these observations have never been fully correlated with the structural change or changes occurring during the anneal. We intend to investigate in detail the effect of metallurgical variables, including heat treatment, on the superconducting properties of hard superconductors. To verify that our experimental techniques are valid and to establish a relative standard against which other materials may be measured, we feel it advisable to know the behavior of the Nb-Zr alloys under a variety of processing conditions. As an initial step toward this goal, we have determined in detail the kinetics of the transformations in Nb-Zr alloys. EXPERIMENT A number of problems had to be solved before beginning any fruitful work on the reaction kinetics in this system. While solving some of these problems, either by chance or by design, small amounts of information were obtained about alloys containing 40, 50, 60, 65, 67, 70, and 75 pct Nb, bal. Zr. In addition, a large range of grain sizes and a range of temperatures considerably greater than the range indicated by Rogers and Atkins phase diagram were examined. We will, however, report in detail only the results obtained for the Nb + 33 pct Zr and Nb + 25 pct Zr alloys at three grain sizes, two levels of oxygen contamination, and the temperature range 550 to 950°C. These data are most complete, but the other data are sufficiently complete to indicate the kind and magnitude of the variation of the transformation kinetics outside this range. The first and most difficult problem encountered in this inquiry was one of sample homogeneity. When Nb-Zr alloys are arc- or electron-beam-melted on a cooled copper hearth, solidification is sufficiently slow that there is appreciable coring in the cast structure and a large variation of grain size across the button thickness. Both these factors significantly affect the apparent reaction rate in the system. A two-step solution to the problem was attempted; an arc-melting and drop-casting technique has been developed by conald that greatly reduces the as-cast grain size and virtually eliminates coring segregation. Ingots made in this way exhibited no detectable (3 pct maximum) zirconium segregation. Before it was evident just how good this technique was, we attempted to supplement it with rather long-time, high-temperature annealing of the cast ingots. This annealing was carried out in evacuated and sealed (seal-off pressures < 1.0 x 106 torr) quartz capsules lined with tantalum foil at 1400 to 1450 C for 8 to 72 hr. There were two principal effects of this treatment: the grain size increased to a fairly uniform 150 p, and the surface and all grain boundaries near the surface acquired a film of a second phase, tentatively identified as an oxide (possibly additionally contaminated with silicon). There was no evidence that this 1400 C treatment had affected the zirconium segregation. High-temperature annealing was subsequently used only for grain-size control, but anneals of longer than 4 hr at temperatures greater than 1000°C were performed in dynamic vacuums (pressure no greater than 1.0 x lo torr). Any contamination resulting from these treatments was well below the limits of detection of our techniques. All samples, as cast, were cold-swaged to at least 85 pct reduction in area. The samples called cold-worked were tested as swaged. The minimum re-crystallization anneal for these alloys was about 12 hr at 1050 C; this produced an equiaxed grain diameter of about 4 to 8 P. Annealing for 4 hr at 1450°C produced a grain size of about 80 to 150 p; and annealing for 4 hr at 1650aC, close to the melting point of many of these alloys, produced a grain size of 0.5 to 1.0 mm. At all temperatures, the larger grain size was

Jan 1, 1967

By A. Sauveur

In an important paper on The Critical Ranges of Pure Iron presented at May, 1913, meeting of the Iron and Steel Institute…

Jan 1, 1915

By Harold Linke

THE following article presents notes and data compiled and computed by the writer for use in the determination of: size and slope of mill launders, details of junction boxes and downspouts, and distribution of pulp. It also includes pulp formulas, volume of discharge through bushings, paths of discharging streams, banking of turns and curves. In the design of a concentrating mill, the draftsman usually considers launders to the extent of providing ample "head" for transmission of pulp from one department of the mill to another. The superintendent of construction aims to build his launders wide and deep, and on a slope steep enough to ensure positive flow. So launders are laid generally on too steep a slope, with the result that the repair gang works to maintain launder bottoms and sides against the erosive action of the conveyed pulp. To this end many kinds of liners have been devised: concrete, mastic, white iron, glass, rubber. True, the reduction of slope to the point where a pulp will flow with minimum wear, will minimize labor and expense; but when the desired slope is not predetermined, the millman hesitates to readjust his launder slopes by cut-and-try methods. To the end that the desired size and slope may be found readily, the writer has: (1) conducted experiments with pulps of different specific gravity, screen analysis and dilution; (2) gathered a few graphic data from standard reference works (such as Peele&apos;s Mining Engineer&apos;s Hand-book and Taggart&apos;s Handbook of Ore Dressing); (3) computed several tables; and compiled results that have proved dependable for Utah Copper ore. It is quite possible that the following tables and graphs may not be applicable to all ores, but it is hoped that they may prove helpful, even in slight degree, in alleviating a portion of the trouble and migraine of some other millman.

Jan 1, 1939

By David White

Jan 1, 1925

By AIME AIME

THE paper by C. H., Lieb on the "Economics of Oil-Producing Practice" (June issue, M. & M.) contains much food for thought. The engineers should be gratified that an executive with Mr. Lieb&apos;s. responsibility should recognize their standing in the industry. Yet after giving them that recognition, he proceeds to spur them on to greater accomplishments by pointing out that their job is only partly done and in some instances poorly done. The operating policies in this paper when applied to new pools with flowing wells are sound. Neither do I take exception to their application to pumping wells. But I do wish to comment on what lie says about price when applied to the many more wells that are approaching abandonment that is, the small producing wells. Mr. Lieb states in effect that higher prices would be detrimental from the long range viewpoint. I doubt that the present prices of crude will provide an ample return from the hundreds of thousands of small wells that have possibilities of substantial recovery by means of water-flooding, repressuring with gas, and air drive. Probably expenditure for experimental work can he justified, but at this time it must usually be considered as experimental. Recently I visited a property where it was estimated that $250,000 would be spent on a 160-acre tract for flooding purposes. The rate of r e t n r n and amount of profit at today&apos;s prices are uncertain. It can be argued that if this type of recovery is not economic with crude at $1 then it can he delayed as it is now possible to secure economically an ample supply of crude from our flush fields. But these old fields still retain large quantities of crude in a dormant state, and should not he abandoned per-

Jan 1, 1936

By ELTCENE A. WHITE

WE are all interested in our ou7n lines of endeavor and consider ourselves the center of the universe. The farmer thinks he is the most important man because he feeds us. The doctor knows he is the real center because he keeps us well. The lawyer says that he is indispensable because he keeps the peace. The banker furnishes us a place to keep our money and tells us how to make proper use of it. The miner sags that without metals there would be no civilization. I think that my branch has sufficient interest and exhilaration. of accomplishment to fully occupy any man&apos;s mind and attention. Mining and metallurgy are as old as the human race. It did not have much, if any, importance in the stone age as there are not found remains of iron and copper, but in the bronze age, which was co-existent with the stone age, it came to the front. Iron and copper were the most important metals. Copper, as bronze, was known in ancient Egypt, I\~:IS important in Rome and other parts of Europe and in Asia; in South America among the Aztecs and farther North were the Mound Builders and the early inhabitants of Lake Superior. At a very early date the Egyptians conquered the Sinai peninsula for the sake of the copper produced there. The history of copper metallurgy can be compared to that of a flower. The seed is sown in darkness and in the Dark Ages the crude metallurgy of copper began. As the shoot comes up from the seed it may be compared to the age of alchemy; the branches of the plant can be compared to the Middle Ages; the flowering shoots to the 17th century, the budding to the 19th and the blossom to our own time from 1870 on.

Jan 1, 1930

By Robin O. Williams

AN investigation has been made of the Ni-Cr system for the purpose of elucidating certain points, namely the nature of aging in both terminal solid solutions and the nature of the phase diagram. Information pertaining to solubilities and precipitation has been obtained. Experimentation Five alloys, Table I, were arc melted in a cold copper crucible using electrolytic chromium and car-bony1 nickel, both dry hydrogen treated. These 100 g buttons were homogenized 24 hr at 1300°C in dry hydrogen and air cooled. Powders were prepared by filing or pulverizing and subsequent heat treatment was done in vacuum or helium using titanium chips as a getter. Powder of —80 mesh was filed from the 60 pct Ni alloy quenched from 1000°C and was sealed in silica under vacuum using a 250 °C outgassing. After aging as indicated in Table I1 the lattice parameters were measured on the quenched samples using the standard cos" 6 extrapolation. These parameters are considered accurate to roughly 0.0001A. In all cases chromium lines of 2.8812 ± 0.0005Å at 30°C were found. Drastic quenching from sufficiently high temperatures produced very sharp body-centered-cubic lines in the first four alloys without indications of transformations. Temperatures to 1250°C were used. Solid samples less than 1/16 in. thick were quenched in water without transformation and the powders could be adequately quenched in small helium filled thin wall silica tubing using a water quench. For those powder samples which were quenched from the two phase field the relative intensity of the body-centered-cubic lines and the face-centered-cubic lines were estimated and extrapolated to give the indicated solubility data in Fig. 1. The data for the two higher alloys were somewhat limited, the plotted points being the lowest temperature where no nickel phase was found. Neither filing, abrading, pulverizing, nor cooling to —190°C produced any new diffraction lines for solid samples quenched from the single phase region, nor did the character of the body-centered-cubic lines change Single phase body-centered-cubic powders likewise did not change on cooling to —190°C. Also, samples which had some precipitation due to inadequate quenching showed no additional changes under these conditions. The first change apparent by X-ray diffraction form samples quenched almost fast enough to prevent precipitation was the diffuseness of the body-centered-cubic lines, particularly on the low angle side, For slower cooling rates the diffuse face-centered-cubic lines appeared. Work on the large grained castings showed profuse streaking through some of the Laue spots while oscillating patterns showed broad body-centered-cubic and face-cen-tered-cubic lines as well as some new lines. For the 23.6 pct Ni alloy the new lines corresponded to 2.16, 1.96, and 1.86A and were more similar in character to the face-centered-cubic lines than the body-centered-cubic lines. Samples which were air cooled gave only face-centered-cubic and body-centered-cubic lines which were still broad. One pattern indicated that face-centered-cubic (111) plane was parallel to a body-centered-cubic (110) plane. For those samples which were examined by light microscopy there were details which were not resolved. However, varied and beautiful structures were obtained. Fig. 2 is of an alloy quenched in a helium filled silica tube from the single phase region and shows particles associated apparently with dislocations which are arranged in low angle boundaries. Finer, general precipitation has also taken place within the grains. Figs. 3 to 5 show the variety of structures produced in these alloys on continuous cooling. It appears that there are four distinct modes of precipitation as evidenced by these, figures. Annealing these structures at higher tem-peratures in the two phase field gives structures as shown in Fig. 6, which shows nickel plates in the chromium matrix which reprecipitated nickel on a much finer scale of the final quench. Lower annealing temperatures and shorter times naturally give finer plates of the nickel-rich phase. Samples of the first four alloys were annealed for appreciable times between 900º and 1250°C and gave structures like Fig. 6. The relative amounts of the two phases were measured and extrapolated to give solubility data as indicated in Fig. 1. The point at 1250°C was deduced from data of Oxx.1 These and most of the other samples were checked for ferromagnetism but none was apparent. In fact, it appeared that the magnetic susceptibilities were not more than three times that for paramagnetic chromium. Discussion In Fig. 1 it is seen that the solubility of nickel in chromium can be represented by a slightly curved line on the usual log X vs 1/T plot, These data are believed to be accurate to roughly 5 to 10º. There is only fair agreement with the data of Taylor and

Jan 1, 1958

By J. A. Hren, C. M. Wayman

RECENT investigators have noted anomalous behavior in the electrical resistivity of vanadium below room temperature. Rostoker and Yamamoto1 in studying the vanadium-oxygen system hypothesized that the body-centered-tetragonal phase existing from 15 to 34 at. pet O at approximately 800°K was really a low-temperature allotrope of vanadium that was stabilized by oxygen. In measuring the electrical resistance of cold-swaged vanadium rod over a range of temperatures, a small discontinuity was observed at approximately 240°K, supporting their notion of allotropy. However, the magnitude of the observed discontinuity was extremely small. Loomis and Carlson2 in studying the ductile-brittle transition in vanadium also made resistance measurements and reported a discontinuity near 200°K. More recently, White and Woods3 showed that the electrical resistivity from room temperature to approximately 100 °K was not linear and at variance with the Bloch-Griineisen law. Instead of finding a discontinuity, they observed a deviation from linearity below 200°K. In discussing their results they pointed

Jan 1, 1961

By E. H. Dix

The success of the Charpy impact test in the steel industry has led those interested in aluminum alloys to investigate the possible application of this test to aluminum and its alloys. In this paper are set forth the results of a few preliminary tests made at the Lynite Laboratories of the Aluminum Manufactures, Inc. In order to study more thoroughly the significance of the Charpy test, slow-bending tests have been made duplicating the arrangement of the impact machine. Tests have been made on both notched and unnotched specimens of a series of copper-aluminum alloys. Apparatus The standard American-made Charpy impact machine delivering a blow of over 200 ft.-lb. was much too large to test aluminum-alloy specimens of the same type used for steel, so that it was necessary either to adopt a larger specimen or to have a special light-weight hammer made. Since there is no known relation between specimens of different sixes, even though geometrically similar, it was decided to adhere to the 10 by 10 mm. specimen. Accordingly, Sauveur and Boylston, the American makers of the machine, were asked to construct a special light-weight pendulum adapted to their standard machine, this pendulum to have one-tenth the capacity of the standard. The writer wishes here to acknowledge his indebtedness to Mr. H. M. Boylston for the personal interest and care exercised in constructing this pendulum. The machine with the light-weight hammer in place is shown in Fig. I. It is mounted on a concrete foundation with the concrete covering the flange on the base of the machine. Vibration is further prevented by four 5/8-in. (15.8 mm.) foundation bolts. The large standard hammer shown against the wall was also used for some of the unnotched bars that required more than 20 ft.-lb. to rupture. When the light-weight hammer was received, it was carefully cali-

Jan 1, 1921

By Peter Tegart

The discovery of gold in the Toodoggone River area is credited to Charles McClair who mined placer deposits in 1925, reportedly valued at $17,500. After he and his partner went missing in 1927, efforts to relocate their workings resulted in the formation of Two Brothers Valley Gold Mines Ltd. in 1933, in which the legendary Grant McConachie (first president of CP Air) played an active role. This was the age when the prospector first utilized the airplane to reconnoitre remote areas. What greeted the observer from the air was an area rich in orange and yellow colours characteristic of gossans formed by the oxidation of sulphides. However, Samuel Black, a Hudson Bay Company fur trader, had also noted in his diary as early as 1824, the unusual and many gossanous colours in the headwaters of the Finlay River. These gossans, coupled with white limestone bluffs and the presence of placer gold, attracted the first reconnaissance of the area by Cominco in 1929. Cominco was ever active in remote areas at this time. They staked and worked several base-metal showings hosted by limestone at the margins of intrusive stocks. These early workers also obtained erratic high gold assays from chalcedony float samples found in creeks draining into the Toodoggone River. However, because the samples gave inconsistent assays, no concerted effort was made to locate their source. Except for the occasional horse-supported prospecting party of the late 1940s and early 1950s, the area did not receive much attention until 1968. Work until this time focused on the base metal lead-zinc showings which contained attractive silver credits. Gold was not an attraction because of the set price established by the US government. The late 1960s saw the northward expansion of porphyry copper exploration into the Toodoggone. A program of gossan soil sampling (gossans which had attracted the early workers) was carried out by Kennco Explorations (Western) Ltd. in 1966-1967. They analysed for base metals in the field, using a cold extraction method. The Kemess copper- gold prospect was staked as a result of anomalous copper values from this early geochemical program. In 1968, Kennco continued the program of silt traversing and field geochemical testing. The samples were further subjected to multielement analysis consisting of copper, molybdenum, lead, zinc, cobalt, nickel, and silver at Kennco&apos;s North Vancouver laboratory. Several anomalous creeks, high in combinations of copper, molybdenum, and silver, were outlined. Some initial soil grids were also established. The fall of 1969 saw the return of Kennco prospector Gordon Davies and geologist Bob Stevenson to check out a well-defined molybdenum, scattered copper and silver anomaly in soils from a grid on the Chappelle claims. The subsequent analysis of several selected quartz felsenmeer floats yielded one assay which ran in the order of 0.25 kg/t (8 oz per st) gold and 2.2 kg/t (70 oz per st) silver. Subsequent trenching on the Chappelle claims exposed the source of float in a 4- m (134) wide vein of high grade gold-silver mineralization. These results led quickly to the realization that the district had precious metal potential. Subsequent exploration in the period 1969-1974 by Kennco resulted in the discovery of most of the gold and silver occurrences on the Chappelle and Lawyers properties. Several other gold and silver occurrences were found in this district by Cordilleran, Cominco, and Sumitomo, working the district during this period. Conwest optioned the Chappelle in 1973 and explored underground by adit entry as part of a one-year program. In 1974, Du Pont of Canada Exploration Ltd. optioned the Chappelle claims and in March 1980, using reserves developed on the A vein, placed the Baker mine into production at a rate of 90.7 Vd (100 stpd). The Amethyst zone on the Lawyers property, 8 km (5 miles) north of Chappelle, was found in 1973 by Kennco using continued, persistent followup prospecting of silver silt geochemical anomalies. A silt anomaly in the order of 3.4 ppm silver occurred in a stream flowing 300 m (984 ft)

Jan 1, 1985

By John I. Yellott

SINCE the days of Newcomen and Watt, when men first sought to turn the energy of fuels to useful purposes, coal-generated steam has supplied most of the power needed for both stationary and mobile applications. The low efficiency and large water requirements of the nineteenth century steam-power plant caused many engineers to turn their thoughts toward more direct means of converting heat into power. As far back as 1791, John Barber secured an English patent on a combination&apos; which he might well have called a "gas turbine." He proposed to generate procducer gas from coal or charcoal, to burn it under pressure in air obtained from a reciprocating compressor, and to drive a turbine wheel with the resultant hot combustion products. With the optimism characteristic of the inventor, he hoped that the turbine would not only operate his compressor but also perform useful work. There is no record that Barber ever built his machine, but if he had done so he would have learned that useful power can result from such a combination only when both turbine and compressor are highly efficient and when the temperature of the gas entering the turbine is not far below 1000°F. Hot-air prime movers continued to attract attention, and both Stirling in England and Ericsson in America2 built reciprocating engines that operated with some success upon coal-heated air. The internal-combustion engine, burning liquid fuels, supplanted the hot-air type, and, for the first time, challenged the supremacy of both the steam cycle and its familiar fuel, coal. LIQUID FUELS COMPETE WITH COAL As the increasing use of the automobile multiplied the demand for gasoline, the supply of residual fuel increased rapidly, and heavy oil declined in price to the point where it became competitive with coal. First in the marine field and later in stationary plants in areas adjacent to refineries, oil began to be widely used. Oil&apos;s greater convenience and higher heating value per pound of weight or per cubic foot of bunker space have caused it to take over much of the marine field. The introduction of the highly efficient diesel engine, capable of burning a fuel that is cheaper than gasoline, again threatened the position of coal, for the operating costs of the diesel became directly competitive with those of coal- burning equipment. In isolated power plants and smaller marine installations, the diesel provided the medium by which oil again successfully invaded fields formerly dominated by coal. The diesel engine, provided with an

Jan 1, 1946

By LESTER H. WOOLSEY

IT IS doubtful whether anything new can be said upon this subject and, therefore, it is with considerable hesitation that l prepare this paper. On account of my recent connection with the Department of State as its law- officer, perhaps I will be pardoned if I discuss this subject briefly from the point of view of that branch of the Government. , I cannot, of course, speak for that department, since I have-no connection with it at-present, but it may be helpful if I set down certain* of the factors which in my opinion and from my experience have a bearing on this international problem. With oil-burning ships, motor vessels, motor vehicles, airplanes-all consuming, astonishing quantities of petroleum or petroleum products; with the United States having within its borders only 12 per cent. of the petroleum resources of the world, and consuming about 70 per cent. of the world&apos;s output; with the more enterprising nations wide awake to the necessity ; of obtaining and preserving as large a share as possible of the oil resources extant ; the &apos;problem is peculiarly and in a, very practical sense an international one.

Jan 1, 1921

By R. A. Matuszak

This paper discusses the major portion of the hoist (drag or crowd) system and it shows how static control accomplishes its major aims. In 1959, the first truly static control for Ward-Leonard equipped electric excavators was designed, developed and placed in service. The control system, originally intended only as a more modern electronic type of alternate to the proven rotating amplifier control system has since proven to be much more. When they conceived the original system, the designers had much more in mind than simply replacing the rotating amplifier with one that had no moving parts. The long range plan, which started with the initial system consisting of an SCR (silicon controlled rectifier) preamplifier and magnetic amplifier power amplifier, called for eventually, a control system low in cost and maintenance, relatively simple in design and extremely reliable. The plan also included the elimination of as many of the shortcomings of the rotating system as possible. No small accomplishment, when it is considered that the rotating control system had been, with only minor modifications, the standard of the industry for 20 years. The final step in the original design plan called for the eventual development of an amplifier that could be used as one of the basic building blocks of the future. DEVELOPMENT RESULTS Since the successful unveiling of the first static control system, continuous development has resulted in a slow, but sure progression along the path described by the original plan. The first version of the new control corrected one of the shortcomings of the rotating system by removing the necessity of operator anticipation. This was accomplished by making the system faster in response so that the operator noticed virtually no delay between his movement of the master controller and that of the machine. Thus, after the operator became familiar with the operating characteristics of the machine, he was able to become more relaxed while digging. The natural result of this accomplishment was higher production. All of the subsequent versions of this new control were even faster than the initial design. Although it was not distinguishable by the operator, the further increase in response resulted in large gains in the limiting of transient torque peaks applied to the machine while digging. Also, a more effective control of the torque and power peaks was obtained when plugging the motion being controlled to a stop. (Plugging is the use of the Ward-Leonard ability to regenerate power and absorb energy from the load to

Jan 1, 1964

By E. P. Sadowski, R. J. Raudebaugh

A study of micro structural characteristics of a 30 pct Cr, 42 pct Ni, 26 pct Fe alloy has been correlated with its behavior in creep and rupture tests at 1400°, 1600°, and 1800°F. Nitrogen pickup observed at 1600" and 1800°F was associated withfissur-ing of specimens prior to fracture. IN studying the high-temperature characteristics of a nominally 30 pct Cr, 42 pct Ni, 26 pct Fe alloy certain anomalies were observed, namely: The alloy had greater stress rupture and creep strength at 1800" than at 1600° F for time periods beyond 550 hr. As placed in test, this alloy was nonmagnetic. After test, some specimens were found to be fairly magnetic. The gain observed in magnetic response was not solely a function of time and temperature of testing. This is a report of the observations and a recounting of the results of studies made in an attempt to explain the behavior of the material under investigation. MATERIAL AND PROCEDURE All test material was taken from a production size heat of an experimental alloy melted and processed using commercial practice and having the following percentage composition: C Fe Cr Ni Ti 0.05 25.83 30.13 41.59 0.41 Al Mn Si S Cu 0.42 0.75 0.45 0.011 0.34 The material was tested in two conditions, namely mill-annealed and grain-coarsened. Mill annealing, which consisted of heating to about 1900° F in a continuous furnace for about 30 min and air cooling, gave a grain size of ASTM 8 and finer. To produce the grain-coarsened condition, mill-annealed material was soaked for 2 hr at 2050°F in a laboratory furnace and air cooled. This resulted in an ASTM grain size of 4 to 5. Rupture tests were carried out at 1400, 1600, and 1800° F in accordance with ASTM procedures. In tests where only rupture life and elongation at fracture were determined, specimens of 0.252 in. diam and 1 in. gage length were used. In tests where creep curves were obtained, specimens were of 0.375 in. diam and 4 in. gage length. Several of the tests under relatively low stress were discontinued short of rupture. Three low-stress tests are still in progress at this writing. Structural changes which occurred during testing were determined from examination of the tested specimens by light microscopy and X-ray diffraction. Diffraction pattern recordings were made with a diffractometer using copper radiation on samples heavily etched in a picric-hydrochloric

Jan 1, 1960

By Earle C. Waite

THE Industrial Minerals Division this year held no individual sessions of its own except the business meeting Tuesday afternoon. One session was held jointly with the Society of Economic Geologists, one with the Milling Methods Committee, and two with the Society of Economic Geologists and the Mining Geology Committee. At all of these meetings the attendance was better than usual and the Tuesday afternoon session, with nearly 400 present, probably set a new record for the Division. Joint sessions seem extremely popular when papers of mutual interest are presented. On Monday afternoon, mica was the predominating subject. The North Carolina mines provided most of the information presented, although the discussion brought out similarities with the New England mines. B. C. Burgess particularly stressed the fact that with the existing curtailment of mica from India it is necessary to get the most mica in the shortest time from the mines in this country. He said that the Colonial Mica Corp. hopes to have 1000 mines operating in the near future. This seems a great number, but when one considers that these mines employ from 3 to 28 men, mostly nearer the low figure, the output of each mine is relatively small. Although the price of mica is from six to ten times the prewar price, the yield of 8 to 150 lb. of mica per ton of raw ore does not provide high returns to the producer.

Jan 1, 1943

By AIME AIME

TWO technical sessions, an excursion through the Midwest refinery and a smoker, marked the first day of the meeting of the Petroleum Division at Casper, Wyo., on Aug. 28. Ninety-nine members and guests registered and there was an excellent attendance at &apos;all functions. The -local committee under the general chairmanship of J. C. Lindsay, general manager of the Western Pipe Line Co., had made every possible arrangement for the convenience and comfort of the visiting members and the Program Committee under E. L. Estabrook, vice-chairman of the Petroleum Division, had brought together a most interesting series of technical, papers. The meeting centered mainly on the various features of the Salt Creek field but there were also contributions from the technology of production in California, the Mid-Continent, and the Texas fields. The opening session was called to order by Mr. Estabrook at the Townsend Hotel on Friday morning. The members and visitors were welcomed appropriately by Ex-Governor B. B. Brooks, president of the "Rocky Mountain Oil and Gas Association, who recalled the changes that had taken place as Casper, a frontier cow town, became a thriving oil metropolis. F. Julius Fobs, chairman &apos;of the Petroleum Division, responded and then took the chair. He introduced H. Foster Bain, Secretary of the Institute, who expressed the regret of those members members who found it impossible to stop over en route to Salt Lake City and his own pleasure at meeting with the Division in the field. Following these introductory ceremonies the technical session began with a "Sketch of the Geological Formations of Central Wyoming," presented by J. G. Bartram of the Midwest staff. It was brief and to the point and contributed greatly to the easy under¬standing of the succeeding papers by those unfamiliar with the region. The talk was illustrated by a large scale columnar section -and a copy of the excellent, geological map of the State recently issued by the U. S. Geological Survey.

Jan 1, 1925

By J. D. Price, W. M. Bertholf

In preparing a paper on coal washing in Colorado and New Mexico, it is difficult to refrain from entering into a discussion of the historical aspects of this subject, for the story of coal washing in these states goes back well into the last century. This phase of the subject could well make a complete paper in itself, and of necessity this present discussion must be limited to current operations. Therefore, we are taking into consideration only those washing plants which have operated for some period during the years of 1947 and 1948.

Jan 1, 1949

By James A. Crookston, William D. Fitzpatrick

Committee C-8 of the American Society for Testing and Materials defines "Refractories" as "Material, usually nonmetallic, used to withstand high temperature," and it defines the term "Refractoriness" thus, "In refractories the capability of maintaining the desired degree of chemical and physical identity at high temperatures and in the environment and conditions of use." The ability to withstand high temperatures is critical to classifying a material as a "refractory." However, as the foregoing definition of "refractoriness" implies, the refractory material may be subjected to and is expected to resist not only high temperatures but a variety of other destructive forces incident to its use. These include abrasion, impact, thermal shock, chemical attack, and high level loads at high temperatures. The various industrial applications of refractories represent an infinite variety of combinations and degrees of severity of these destructive forces, including high temperatures. Naturally, such a variety of application conditions leads to a need for a wide variety of refractory products to satisfy those conditions. The number of refractory products available is great enough that some form of classification is necessary to a discussion of refractories. Refractories may be classified in several ways, but the most suitable one is based on their general compositions and to lesser degrees on their physical condition and distinctive properties. The primary types of brick include aluminosilicate brick (fire clay and alumina), basic brick (magnesia and chrome ore, alone and in various combinations), silica brick, insulating brick, and special refractories (carbon, Sic, ZrO,, zircon, borides, and nitrides). Brick are, of course, preformed and are usually heat treated at high temperatures before use, but are in some instances unburned and/or chemically bonded, including the relatively new class of tar-bonded magnesia and/or dolomite brick. In addition to preformed refractories, another broad category includes the so-called specialty refractories, which are usually made in the same types as itemized for brick-bonding mortars and high temperature cements, hydraulic setting castables or refractory concrete, plastic firebrick, and ramming mixes. Refractory grains, such as fire clay and high alumina calcines, dead-burned magnesite and periclase, and dead-burned dolomite are also considered refractory products. Brick are also classified on the basis of physical dimensions, as standard sizes and special shapes. The standard sizes are those which are of definite shape and design and are designated as 9 x 4 ½ x 2 ½ in. and 9 x 4 ½ x 3 in. straights and series. All other brick of non- standard sizes are referred to as special shapes. These come about as a result of a particular need for a given furnace or for a particular application.

Jan 1, 1975

By A. C. Fieldner

IN the Wall Street journal for March 1, 1941, was a tabulation of the construction under way or under negotiation by thirteen iron and steel companies for a predicted increase in annual coke production of 3,165,600 tons. That even this figure was short of the mark is indicated by other plans, then being considered, for a later expansion of 2,610,000 tons additional. Considerable progress has already been made on thin program, for approximately 500 new ovens were put in operation in 1941. and well over 200 should be completed in 1942. These figures include a number of units that replace older and obsolete equipment.

Jan 1, 1942