Search Documents

Established as a Division March 24, 1922 T C Frick, Chairman R B Gilmore, Past Chairman T A Atkinson, Vice-Chairman R C Earlougher, Vice-Chairman Glenn M Stearns, Treasurer Joe B Alford, Executive Secretary 800 Fidelity Union Building , Dallas 1, Texas

Jan 1, 1956

JOHN H. NELSON, Worcester, Mass.-At our plant we have done considerable work on notch-bar testing and are farther at sea now than when we started. So far, we have been unable to get the notch-bar test to be consistent with any other known test. Lately, I have been investi-gating the effect of the position of the notch-bar specimen in a, bar. To do this I took a 3, ½ in. square bar and quartered it, then heat treated the four quarters. Each of these pieces was again quartered and a specimen machined and notched. "In this way we would have notch-bar tests from the exterior to the interior of the bar. These were made of such lengths that it was possible to make four impact tests on each speci-men. Extreme care was taken in marking the position of these test speci-mens in the original bar. The notches were then cut with relation to position of the specimen in the original bar. The second notch was cut 90° from the first, and so on around the specimen. In this way, we have found that, with a 3 ½ in. bar of 0.4 or 0.5. per cent. carbon steel when properly heat treated, we could get impact values ranging from 15 to 100 ft.-lb. Just why this is the case we are unable to state; but it does appear to be a fact that along the outside of the original bar the notch-bar test seems to be low and increases toward the center, but it is not always consistent. For instance, we may have, on a single specimen; one notch-bar test giving us 15 ft.-lb. and another 100 ft.-lb. We have not found such inconsistencies in alloy steels. Alloy steel is consistently good or consistently bad. If it. is good, you cannot readily destroy the impact value, no matter what you do; if it is bad-that is, if it is a poor notch-bar steel-and you have sufficient latitude in your draw, you may correct it. In other words, if the hardness you are working to will allow you to draw to about 1050° F.(561° C.) or over and then quench this steel from the draw heat, you. can raise the im-pact value of the steel from about 4 or 10 ft.-lb. up to-40-or 50 ft.-lb: Just what occurs I do not know. There is evidently a critical-point in steels that have poor impact value, in the neighborhood of 1000 F. to 1050° F. (536° to 561° C.).

Jan 12, 1919

By W. L. Phillips

Stress-strain data are reported for sodium chloride, lithium fluoride, and magnesium oxide tested in compression at diffevent strain rates in the telrlperature range from 70° to 873°K. Quantitative equations are given for the stvain-rate dependence of the critical resolved shear stress and the initial rate of work havdening. The properties so determined are compared with results previously reported for metals. ALTHOUGH the effects of strain rate and temperature on the stress-strain characteristics of metals have been extensively investigated1,2 these effects have not been studied in detail in ionic crystals. In the only previous investigations on the effect of strain rate on the deformation of ionic crystals. Gilman and gohnston3 and Hulse and pask4 have shown that the yield stress of lithium fluoride and magnesium oxide at room temperature is proportional to the ninth or tenth root of the strain rate. CRYSTAL PREPARATION Lithium fluoride, sodium chloride. and magnesium oxide single crystals were purchased from the Har-shaw Chemical Co. The compression fixture and sample preparation have been described in detail previously.5 The detectable impurities in MgO were eight parts in 105 of Fe and six parts in 105 of Si; in LiF, six parts in 105 of Mg; and in NaC1, two parts in 105 of Fe and four parts in 10&apos; of Mg. The cleaved samples measured - 0.1 in. by 0.1 in. by 0.3 in. Prior to testing all samples were annealed at -0.8 of their melting point and cooled to room tempera- ture at 50 C per hr.&apos; Samples were strained at rates (<) of 0.1, 0.01, 0.002, and 0.0002 in. per in. per min. EXPERIMENTAL RESULTS Fig. 1 is a plot of the critical resolved shear stress a,. (extrapolation of slope of easy glide region to zero strain) of sodium chloride, lithium fluoride, and magnesium oxide tested at different strain rates as a function of temperature. In all crystals at all strain rates a, decreases with increasing temperature according to an equation of the type397 where uo is a stress constant, K is a constant, and T is the absolute temperature. The points in Fig. 1 are the average of six tests. It is evident that there is a break in the log 0,- temperature plots at a characteristic temperature T,. The constant K of Eq. [I] is dependent on strain rate, Fig. 2. The relationship

Jan 1, 1962

Arthur Yates, lecturer in the mining department of the Royal School of Mines, London, died at Blackpool, on Feb. 14, 1923, at the age of 47 years. My first acquaintance with him was made in 1902, when taking over the management of the Redjang Lebong gold mines in Sumatra, of which he was the responsible metallurgical officer. For that position he was well qualified by reason of his previous experience with the Rand Central Ore Reduction Co., in South Africa, and particularly by his early training with the Cassel Gold Extracting Co., owners of the MacArthur-Forrest patents, and the first commercial company formed to work the then recently discovered cyanide process; in this connection, Mr. Yates had the advantage of working under J. S. MacArthur himself. Our association in Sumatra was maintained for six years, when I left. Mr. Yates remained and was eventually promoted to the management of the neighboring Soelit mine. During those six years and in the close association inseparable from life in an isolated mining camp, the sterling qualities which made him so good a man were unmistakable: industry and interest in his work, patience with everybody, a quiet and unassuming demeanor. On the exhaustion of the mine to which he had been promoted, he returned to England in 1913. In 1914, the Mining Department of the Imperial College was fortunate in securing his services. Hardly, however, had he settled down when the war broke out and he spent some years in the Cleveland District promoting the efforts of the Government toward greater output. Returning to college in 1919, Mr. Yates met the full flood of Service students. The qualities which made him a man amongst men in the world made him a man among students in the college; a senior student if you like. But, unsuspected, a dread disease had fastened itself upon him, making itself felt for the first time during the summer course he was conducting in the South Wales coal field, in 1922. Against its relentless onset he opposed the bravest optimism, and when at last he realized that he was going under, and was in fact dying, his pronounced regret was that he was leaving the boys. In his death, at the age of forty-seven, staff and students in the Mining Department have experienced a great loss, that of a reliable friend, and their deepest sympathy goes out to the young widow and son in their irreparable loss. S. J. TRuBcott.

Jan 1, 1923

Arthur Yates, lecturer in the mining department of the Royal School of Mines, London, died at Blackpool, on Feb. 14, 1923, at the age of 47 years. My first acquaintance with him was made in 1902, when taking over the management of the Redjang Lebong gold mines in Sumatra, of which he was the responsible metallurgical officer. For that position he was well qualified by reason of his previous experience with the Rand Central Ore Reduction Co., in South Africa, and particularly by his early training with the Cassel Gold Extracting Co., owners of the MacArthur-Forrest patents, and the first commercial company formed to work the then recently discovered cyanide process; in this connection, Mr. Yates had the advantage of working under J. S. MacArthur himself. Our association in Sumatra was maintained for six years, when I left. Mr. Yates remained and was eventually promoted to the management of the neighboring Soelit mine. During those six years and in the close association inseparable from life in an isolated mining camp, the sterling qualities which made him so good a man were unmistakable: industry and interest in his work, patience with everybody, a quiet and unassuming demeanor. On the exhaustion of the mine to which he had been promoted, he returned to England in 1913. In 1914, the Mining Department of the Imperial College was fortunate in securing his services. Hardly, however, had he settled down when the war broke out and he spent some years in the Cleveland District promoting the efforts of the Government toward greater output. Returning to college in 1919, Mr. Yates met the full flood of Service students. The qualities which made him a man amongst men in the world made him a man among students in the college; a senior student if you like. But, unsuspected, a dread disease had fastened itself upon him, making itself felt for the first time during the summer course he was conducting in the South Wales coal field, in 1922. Against its relentless onset he opposed the bravest optimism, and when at last he realized that he was going under, and was in fact dying, his pronounced regret was that he was leaving the boys. In his death, at the age of forty-seven, staff and students in the Mining Department have experienced a great loss, that of a reliable friend, and their deepest sympathy goes out to the young widow and son in their irreparable loss. S. J. TRuBcott.

Jan 1, 1923

By Fred Wise, C. W. Wark

THE Getchell mine, a comparatively recent gold discovery, is in the old Potosi mining district, Humboldt County, Nevada. All ore is mined from open pits using Diesel shovels and gasoline trucks. Two types of ore are mined, oxide and sulphide. Oxide ores are siliceous or shaly; sulphide ores either gougy, siliceous or shaly. In mining, the sulphide ore is segregated into hard and gougy ore, because the gouge must be dried before it can be crushed. The oxide ore is not segregated. GENERAL METALLURGY The oxide ore is the leached outcrop that overlies the sulphide ore body. All of the iron and arsenic sulphides found in the sulphide ores have been thoroughly oxidized. The sulphur and arsenic have been leached out while the iron is present as hematite and limonite. The oxide ore is amenable to direct cyanidation, and although no visible free gold is present it is released at a comparatively coarse grind. The sulphide ore is more refractory, since the gold is all of micron size and some of it is locked in fine sulphides. It has been established microscopically that the free gold is coated with an impervious shell, which is probably some form of iron compound. The sulphide ores contain from 1.5 to 2 per cent of arsenic, which is present as orpiment and realgar with minor amounts of arsenopyrite. The orpiment and realgar are of a later mineralization than the gold and are barren. Roasting and washing of the sulphide ore prior to cyanidation is necessary to eliminate the arsenic, to alter the gold coating from an insoluble form to a soluble form, and to release the gold associated with the fine sulphides. Washing the ground calcine in weak sulphuric acid, trona, or hot water are beneficial in the order named, but to date the water is the best from an economic standpoint. Metallurgical tests as well as plant practice indicate that a certain amount of gold cannot be recovered even by going beyond economic practices. On this basis metallurgical results are viewed in the light of an optimum tailing rather than a percentage of extraction. MILLING PRACTICE Crushing (Fig. 1).-There are three primary ore bins, one each for oxide ore, gougy sulphide ore, and hard sulphide ore. In front of each bin a substantial yard is maintained, which makes it possible to stockpile 2500 tons of oxidized ore, 1000 tons of hard sulphide ore, and 1000 tons of gougy sulphide ore. The bins are fed by a 60-hp. caterpillar bulldozer from the stockpiles. Fig. 1 shows the method and

Jan 1, 1940

By AIME AIME

NOT a few physical metallurgists started their profession- al careers as chemists or physicists, only to surrender later to the attractions of metallurgy. The present Institute of Metals Chairman varied this more usual sequence in hat his first love was electrical engineering, when as a recent graduate he served on the staff of the General Electric Co., of Schenectady. Soon turning to metallurgy as a more interesting field, he was metallurgist and then chief engineer of the Wads- worth Watch Case Co. from 1920 to 1927. Since 1927 he has been with the International Nickel Co. at the Bayonne, N. J., research laboratories where he is staff adviser.

Jan 1, 1940

By AIME AIME

AMERICAN INSTITUTE OF MINING ENGINEERS. Vii MEMBERS&apos; PRIVATE RECEPTION ROOM. A separate room in the suite occupied by the American Institute of Mining Engineers on the ninth floor of the United Engineering Society Building, has been equipped with furniture and telephone extension for the use of members of the Institute who desire temporary private office accommodations. In order that the benefit of this arrangement shall not be restricted to a few members only, the length of time of continued occupancy is limited, and applications will be considered in the order of their receipt. A small fee will be required for the use of this room.

Jan 9, 1907

By S. A. Ford

I WOULD like to call the attention of our Bessemer steel manufacturers to a few facts in regard to the action of the manganese in. the Spiegel with the oxide of iron in the blown iron. The oxygen is united with the iron as a magnetic oxide, as Gautier asserts, and this oxide is reduced to a protoxide by one-atom of the manganese uniting with one atom of the oxygen of the magnetic oxide of iron. This oxide of manganese and the protoxide of iron thus formed unite with the silica which has been formed by the oxidation of the silicon in the pig iron. Mr. Snelus and others

Jan 1, 1881

By Murray F. Hawkins, Marion L. Kimmel

sage&apos; appears to have been the first (1933) to design a rolling ball viscosimeter for the express purpose of measuring the viscosity of oils with natural gas in solution, i.e., under reservoir conditions. In 1940 Hocott and Buckley&apos; further refined the rolling ball instrument in both design and method of operation, and their instrument, known as the Humble type, was the forerunner of present day viscosimeters used in petroleum production and research laboratories. They also initiated the technique of charging the viscosimeter with a sample directly from a bottom hole sampler. In 1948 the committee on engineering research 01 the Petroleum Division of the AIME in Part 3 (1) of

Jan 1, 1955

CANADA, which appears to be growing into one big mining camp, may soon be the background for another impressively large iron ore development. And again it will be Fenimore Iron Mines who will be the motivating force. Dr. J. A. Retty, Fenimore president, who was one of the important figures in the development of Labrador iron deposits, predicts a great future for property on the west coast of Ungava Bay in deep northern area of New Quebec. Fenimore properties consist of a 200 sq mile concession in addition to several hundred claims over about 112 miles along the Labrador trough, mainly in the Ungava Bay region.

Jan 5, 1953

Although the meeting of the Institute in St. Louis Will not occur until September, 1917, the committee in charge is already making attractive plans, and we append hereto a tentative skeleton program which will give some notion of the opportunities that will be offered: St. Louis is situated in the midst of. a district which contains not only a great many interesting examples of mining, but also all types of industrial manufacture of interest to members of the Institute, and it affords abundant opportunities to visit and see these plants. Further announcement will be made from time to time as the committee&apos;s plans take more permanent shape. .

Jan 2, 1917

By H. V. Fairbanks

Efforts were made to determine the amount of increase in the drying rate which could be obtained through acoustic treatment of ultra fine coal under various conditions, and to test the feasibility of using a rotary kiln and multitiered vibrating screens as a means for continuous drying of coal fines. Introduction of acoustic energy during the rotary kiln experiments increased the drying rates from 10-40%, depending upon the experimental condition. The use of a drying assembly consisting of multitiered vibrating screens produced better results than the rotary kiln and has definite possibilities of providing an effective means of drying coal fines in relatively large quantities.

Jan 1, 1973

By Gordon Fletcher

Pacific Rim countries currently have plans to import about 100 Mt/a (110 million tpy) of steam coal by 1990. Due to its close proximity, Powder River Basin coals offer a long term economic and dependable source of supply to the Pacific Rim. In existing boilers, Powder River Basin coals can be blended with Australian, South African, or Canadian coals. For new units, Powder River Basin coals are very competitive on a total evaluated cost basis. The advantages of using Powder River Basin coal include: assurity of supply, consistent coal quality, stable labor force, and attractive mining economics. (NOTE: PAPER NOT RECEIVED IN TIME FOR PUBLICATION.)

Jan 1, 1982

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons.) The governing body of the Imperial College of Technology, London, S. W. (Royal School of Mines), will shortly proceed to the appointment of a Professor of Metallurgy. This important Chair has been filled in the past by such eminent metallurgists as John Percy, Sir William C. Roberts-Austen, and others. Inquiry has been received at the office of the Institute for an engineer to examine a mica, deposit in one of the New England States. The position of converter blower at. a side-blow Bessemer steel casting plant is vacant.

Jan 4, 1913

By William B. Plank

STATISTICS just released by the American Society for Engineering Education and given in the table, show that the total current enrollment of 200,227 in the 220 engineering schools of the U. S. and Canada represents a gain of 9.8 pct over a year ago, while the mineral engineering enrollment in the U. S. of 9826 shows a gain of only 4 pct in that field. The spurt in the mineral group shown last year is thus slowed down to less than one half of that in the whole engineering student body. Last year, it was growing more rapidly than the whole engineering group.

Jan 5, 1954

By W. R. Toeplitz

H. N. Ghenn.*—It has been established that the accuracy obtainable from any precision machine is a function of the wear resistance, maintenance and closeness of fit of the bearings, hence I would like to ask Mr. Toeplitz how these oil-less bearings compare with cast iron or babbitt or similar materials when used on precision machinery. Could these bearings be used, for example, on a grinding machine in which work must be held to a tolerance of plus or minus 0.000025 inch? W. R. TOEPLITZ.—The metal-powder bearings can be held to very close tolerances and are used in place of cast iron and babbitt on precision machinery.

Jan 1, 1945

By A. Long, A. Silverman, J. L. Kulp

Garth Crosby has written an excellent geologic description of the deposits surrounding the Gem stocks in the Coeur d&apos;Alene district. The ore deposits in the area of the Gem stocks may hold the key to the age and mineralization history of the entire Coeur d&apos;Alene district. A recent isotopic study of the Coeur d&apos;Alene district in this laboratory illustrates that a classical geologic interpretation of these deposits, with its implications for the whole district, may lead to erroneous conclusions. For this reason it seems pertinent to submit a summary of these results and an interpretation of the mineralizing history of the Coeur d&apos;Alene districts.

Jan 5, 1960

WE vote this month without knowledge of either major presidential candidates&apos; position on mineral problems. Too long have we kept our own counsel, turned our backs on the public. Certainly we must formulate policies upon which we may unite in industry council, but implementation of these by legislative bodies requires popular understanding, if not support. The earth and its resources are the province of the miner and the farmer but beyond this, and the basic need of the economy for both, the similarity ends. In this election year the disparity between the poll strength of these two fundamental callings is apparent. While both candidates have found it essential to incorporate a farm plank in their platforms, mining has been neglected as not being a basic issue. If this gives the mining fraternity the advantage of voting objectively, it also leaves the general public in the dark as to the attitude of the candidate on a basic issue. It is an issue on which depends the future of the nation, but, unfortunately, the public is not aware of its own vital stake in mining. Thus election time brings with it a fresh example of the evils of automatic lawn sprinkling-a long standing peeve of ours. Back in the days of the hand-held sprinkling hose in the intimacy of the twilight the mining man had the opportunity to unburden himself on the problems of mining to his neighbor who might be a doctor, lawyer, or accountant. With the encroachment of mechanized sprinkling, yet another forum for the indoctrination of the layman into the significance of mining has disappeared. Familiarizing your neighbors with mining in the lawn sprinkling societies of yesteryear was the individual&apos;s contribution to public relations for mining. The corporations can use educational advertising in popular magazines as is practiced by such companies as Kennecott. The AIME can play an important part by providing career guidance information on the mineral industries. We offer the suggestion to the American Min¬ing Congress, that the splendid exhibitions of mining machinery featured in alternate years for metal and coal mining, respectively, might be opened to the general public one night during the week of the show. Newspaper publicity would add greatly to the public&apos;s interest in such an opportunity. Power for the public is considered a vote-getter and no candidate has neglected to make his stand on this subject. Is the price of the kilowatt in the home of greater importance to the voter than the price of the metal durable goods which he purchases every year? Not really, but the voter thinks so. Mining has as much sales appeal as &apos;potatoes or kilowatts if presented in the proper way. We suggest that a little hand lawn sprinkling by the right people in the right places would produce an abundance of publicity which would give Mr. and Mrs. American something new to expect from their representatives-a vigilance over the flowering of their mining industry.

Jan 1, 1952

By Joseph J. Becker

RECENTLY the "oriented growth" hypothesis of recrystallization textures has been receiving considerable attention. According to this view, "whenever a new generation of grains is growing in a highly oriented matrix . . . one may assume . . . that from among available nuclei of a great variety of orientations those with suitable orientation relationship with respect to the matrix have by far the highest rate of growth (oriented growth) and will, therefore, predominate."&apos; This statement includes primary recrystallization of single crystals and of polycrystalline materials showing strong deformation textures as particular cases. While the phenomenon of oriented growth undoubtedly does operate, and may be of importance in coarsening or secondary recrystallization, the writer feels that its extension to primary recrystallization is a different matter. Several aspects of this phenomenon may be pointed out which are difficult to rationalize on the basis of oriented growth. In recrystallizing deformed single crystals of alpha brass, Maddin, Mathewson, and Hibbard2 found that the twin composition planes of the recrystallized grains were parallel to the three operative slip planes they observed, and not to the fourth octahedral plane. The writer&apos;s current work seems to indicate further that when only one or two slip systems can be seen to operate, the recrystallized grains are aligned only with those slip planes actually observed. This behavior could hardly be accounted for by oriented growth, because on the latter basis the recrystallized texture of a deformed single crystal should certainly have the same symmetry as the crystal itself. Growth rates could not be expected to distinguish between crystallogra- phically equivalent directions, unless the presence of a visible slip system vastly increases the growth rate in the appropriate direction. This seems unlikely. These relationships were observed by the writer only when considerable care had been exercised before annealing to etch away the effects of cutting out the centers of tensile specimens with a jeweler&apos;s saw and to etch off the ends of compression specimens. When these.precautions were not taken, nu-cleation inevitably appeared to occur at the saw cuts or at the ends, and the resulting orientations never showed a [111] rotation but appeared quite random. The provision of many nuclei of many orientations did not enhance the correlation, but destroyed it. Recrystallization textures are sometimes strongly dependent on annealing temperature, which would imply that the anisotropy of growth rates is a suddenly varying function of temperature. This might be regarded as unlikely. Recrystallization textures can be strongly dependent on the degree of deformation. If textures are to be explained by selective growth from among nuclei of all orientations, it is difficult to see how the recrystallization process could have any dependence whatever on the manner or degree of deformation. It is felt that the above points should be considered before the oriented growth hypothesis is applied to primary recrystallization, with the necessary complete divorce of the mechanism of recrystallization from the details of the deformation process. References 1P. A. Beck and H. Hu: Reply to discussion of their paper on Recrystallization Texture and Coarsening Texture in High Purity Aluminum. Trans. AIME, 188, 1057; Journal oF Metals (Aug. 1950) TP 29083. &apos;R. Maddin, C. H. Mathewson, and W. R. Hibbard, Jr.: The Origin of Annealing Twins in Brass. Trans. AIME, 185, 655; Journal of Metals (Sept. 1949) TP 26763.

Jan 1, 1952