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By E. J. MCOAUSTLAND

THE behavior of steel after overstrain and at moderate temperatures is fairly well known. It has been made the subject of much investigation, and our knowledge is clear and definite on many points. The ultimate raising of the elastic limit, after moderate overstrain, and the consequent lowering of the ductility, seem to be well established. It is also well understood that the immediate effect of overstrain is to lower the elastic limit, possibly to zero, but that if not interfered with, this limit will subsequently rise higher than before. The "tests after moderate temperature," reported in this paper, were undertaken to verify the above statements for the particular steel under investigation, and also to determine, if possible, the total time required for complete recovery from this state of overstrain. The behavior of overstrained steel at temperatures at or below 32° F. is not so well known. Tests made by Prof E. G. Coker, at McGill University,' show that steel, overstrained and subjected to cold, will remain in a state of overstrain for an indefinite period. I am not aware of any other published results of tests along this particular line. The effect of time and temperature on the recovery of steel from overstrain was made in 1902-3 the subject of sortie investigation in the laboratories of the College of Civil Engineering of Cornell University. A general plan was outlined in connection with the regular courses of instruction in testing of materials; but the press of routine work and the demands of the schedules on the time of the students were so great as to presage long delay in the completion of the work. Not much had been accomplished up to 1904-05, when Messrs. E. C.

May 1, 1906

By J. L. Gissy, G. H. Schippereit, J. B. Schroder

THE existence of mechanical anisotropy in hexagonal metals is well known.' One possible method of measuring the degree of anisotropy in a metal is to make hardness measurements on the different planes of a single crystal. So far as is known, no single-crystal hardness data have been reported in the literature for alpha titanium. To obtain an estimate of the variation in hardness with crystallographic direction in titanium, Knoop hardness measurements were made on single crystals of electrorefined alpha titanium obtained from the Bureau of Mines, Boulder City, Nev. The hardness of arc-melted ingots prepared from this material was 64 Bhn (1000-kg load, 30 sec). Crystals of sufficient size were mounted in epoxy resin with the basal plane exposed. They were then polished and etched to remove excess plastic resin and work-hardened surface material. The crystals were then examined by x-ray diffraction, using the back-reflection Laue technique to insure that the crystals were properly oriented and strain free. After Knoop hardness readings (100 or 200-g load) were taken on the exposed surface, the crystals were remounted to expose a prismatic face and the foregoing procedure was repeated. Hardness values for various orientations are listed in Table I. The data show a difference between the hardness of the basal planes and that of the prismatic planes, as anticipated. More striking is the hardness difference observed between different orientations of the indentor on the prismatic planes as shown in Table I and Fig. 1. All of the indentations shown in Fig. 1 were made with a 100-g load. The long axis of indentation A is parallel to the unique (c) axis of the crystal. The deformation marks visible around indentations A and C of Fig. 1 are probably slip traces of the (10.0) system reported by Rosi, et al. The greater hardness observed when the long axis of the indentor was perpendicular to the unique axis of the crystal (indention B) is probably caused by the opera-

Jan 1, 1959

By J. Avraamides

Many of the current methods for producing metallic silver particles having specific characteristics involve several steps, are time consuming and subject to contamination. The novel non-aqueous chemistry of silver and copper is used in a simple two step process capable of producing high purity silver powders of specific size and shape. The chemical basis of the process involves the manipulation of the equilibrium -- Cu(I1) + Ag [=]Cu(1) + Ag(1). The addition of at least 50% (V/V) acetonitrile (CH3CN) stabilizes both Cu(1) and Ag(1) ions in aqueous sulphate medium, and the metallic silver dissolves. Removal of the volatile nitrile by distillation reverses the equilibrium and silver powder is precipitated. The nature of the powder depends on the presence of additives such as gelatin, thiourea and polyacrylamide.

Jan 1, 1984

By Henry Louis

THE work performed by the Royal Commission on Mining Subsidence is likely to prove of permanent value, less perhaps for the conclusions it has reached and for the recommendations it has based upon these than for the admirable exposition which it affords of the law concerning mining subsidence and of the legal status of the person who has suffered damage by reason of such subsidence, as also of him whose working has caused the damage. The Commission was appointed by Royal Warrant in the middle of 1925 and delivered its final report in the middle of 1927. The terms of reference to the Commission were as follows: "To consider the operation of the law relating to the support of the surface of the land, and of buildings or works on or under the surface, by underlying or adjacent minerals; to enquire into the extent and gravity of the damage caused by subsidence owing to the extraction of minerals and the incidence of the resulting liability; and to report what steps should be taken, by legislation or otherwise, to remedy, equitably to all persons concerned, any defects or hardships that may be found to arise in existing conditions."

Jan 1, 1929

By Elmer W. Pehrson

NINETEEN FORTY-SIX was an eventful year for the mineral industries. Perhaps the most significant development was the socialization of industry in Great Britain, initiated in 1945 but carried to fruition in the coal industry in 1946. On Jan. 1, 1947, management of the coal industry will be vested in a National Coal Board, responsible to the Ministry of Fuel and Power. A sum of £164,660,000 has been provided to compensate private owners for assets transferred to the Board. The British coal industry has been a problem for many years. Production has declined to a point where serious shortages of fuel for domestic needs have developed. Exports have dwindled to a small fraction of the previous trade. Costs have increased greatly, and quality has deteriorated. The industry's physical plant has not kept pace with the rapidly mounting wage scales in recent years. Some claim that the best and most accessible coal reserves of Britain are heavily depleted. The industry has been harassed by difficult labor problems, including bad morale among the workers and a shrinking labor force.

Jan 1, 1947

Geological and Natural History Survey of Minnesota, Minneapolis, Minn W. H Emmons, Director A list of publications will be sent upon application Orders for publications should be addressed to The University of Minnesota Press, Minneapolis, Minnesota The Geological Survey of Minnesota has a record of long and useful service Some of the papers published have been outstanding in their field A series of 24 Annual Reports, covering the years 1872 to 1895-98, inclusive, was issued, of which 16 are still available at a price. More important however, are the six volumes of Final Reports, in which is collected the material presented in the earlier Annual Reports. All the strictly geological papers are found in four of the volumes of the Final Reports. vol 1 (1872-1882), principally geology by counties, 2 (1882-1885), same as 1, 4 (1896-1898), same as 1, 5 (1898-1900), Structural and petrographic geology Prices for each volume, leather $3, cloth $2 50, excluding postage, unless other directions accompany the order, volumes of the Final Reports will be sent express collect. A series of Bulletins has been issued, of which a few are out of print. Considering only those available, and of greatest interest, they are: Bulletin 5, Natural gas in Minnesota, by N H Winchell (1889), 50 cents, 6, Iron ores in Minnesota, their geology, discovery, development, qualities and origin, by N H Winchell and H V.

Jan 1, 1933

By Hiland G. Batcheller

HISTORY shows that the nation which makes the most steel is the most likely to win wars. Today the course of war shows that the nations which get there first with the most steel of the right kind will be the ones to win. Not only the most steel, mind you, but the right kind. Adequate production, which was enough for victory before the days of totally mechanized warfare of 1943, must now be accompanied by still better quality as well as more effective distribution. Further, both production and distribution must be flexible enough to permit rapid shifts from one weapon to another for use in varying elements in varying geographical areas. Thus the problem of making enough steel of the right kind at the right time in the face of changing requirements dictated by experience has been and will remain highly complex. This does riot permit us to ease our restrictions on nonessential use. War is a complex business, like the job of making steel for war. Each time we solve one problem, another pops its head up. Yet we are making some progress.

Jan 1, 1943

By W. D. B. Motter

DURING the early development of blasting with liquid oxygen explosives the trend of experimentation was towards increasing the effectiveness of the explosive. Its characteristic of becoming inert after evaporation of the oxygen content made a strong appeal from the standpoint of safety, especially with missed holes. It later became apparent, however, with practical use of this explosive, that LOX lacked certain other safety characteristics. As its effectiveness was increased, it became more subject to detonation by impact. The object of this paper is to show the steps taken by one operating company to achieve greater safety in the large-scale handling of liquid oxygen explosives.

Jan 1, 1933

By Herty, C. H.

Three distinct processes take place during the conversion of iron ore to steel. First: the raw ore is reduced to metallic iron in the blast furnace and during this reduction certain constituents are dissolved in the iron, either through the solution of a solid into a liquid phase, as in the case of carbon, or by reduction of an oxide existing in the slag to the metallic element of that oxide, with subsequent solution of the metallic element in the iron. Thus by the process of solution and reduction, a pig iron results which contains about 4 per cent carbon, 1 per cent silicon, 1 to 2 per cent manganese, 0.1 to 0.4 per cent phosphorus, and 0.03 to 0.10 per cent sulfur. To obtain a sufficient yield of iron from the ore it is necessary that the reducing process be carried as far as possible, with the result that the impurities mentioned accompany the reduced iron. Second: to convert this iron into steel it is necessary to oxidize a part of the iron in eliminating the impurities to the extent desired for the particular product being made. In eliminating these impurities by oxidation a certain amount of iron oxide (FeO) dissolves in the steel. This dissolved FeO reacts with the metalloids, except sulfur, and to eliminate them to the desired extent it is necessary to leave a considerable amount of FeO in the metal. The reaction of iron oxide with silicon, manganese, and phosphorus results in the formation of the oxides of these elements. The oxides enter the slag and the extent of elimination of the elements depends on certain equilibria between the slag and the metal. The reaction of FeO with carbon results in the formation of the gases CO and CO, which, after saturating the metal, pass into the furnace gases. Third: after the iron has been purified to the desired extent as far as the elements listed are concerned, it is necessary to deoxidize the bath to remove the FeO, which is the vital factor in gas formation as the steel solidifies.

Jan 1, 1957

By Franklin Moeller

Considering the really short time that has elapsed since hydro-metallurgical processes of extracting copper from ores have been extensively developed, and the large scale on which this method is practised at Ajo, the successful operation of the plant must excite the admiration of every visitor. The application of the mechanical unloader to the purpose for which it is employed at Ajo is but an extension of the use for which it was originally designed, some 20 years ago, for unloading iron-ore vessels at the lower lake ports. At a time when the maximum output of a single machine, with men shoveling the ore into buckets, did not exceed 40 tons per hour, G. H. Hulett invented and constructed a mechanical unloader with a bucket of 10-ton capacity. This machine was of the steam hydrauIic type, and it is still in operation after nearly 20 years of service. Several more machines of the same type were built, but the difficulties of power transmission, and the rapid development of electrical machinery, soon led to the adoption of electrically operated machines, and practically all of the later installations have been thus equipped. This electrically operated unloader has proved so well fitted for the work that the design of the lake boats has been practically revolutionized, with special view to the ease and rapidity of unloading. It is now possible to unload a 12,000-ton vessel with four machines in a little over 2 hr. This has necessitated an increase in the capacity of the machine, and the largest yet built handles an average load of 17 tons, with a possible maximum of 20 to 21 tons. The Ajo excavator is somewhat simpler in design than the iron-ore unloader, in that it is not provided with a larry. In the unloader, the iron ore, picked up by the bucket, is delivered to a larry or transfer car which runs in the lower chord of the bridge; the larry then delivers the ore either into railroad cars, standing on several parallel tracks, or into the stock pile, thereby saving the time that would be required for the bucket to make the trip. At Ajo, the bucket delivers the tailing

Jan 1, 1920

By Robert S. Shoemaker

Recently we read a short article which stated that Marcona Corp. was studying the use of 25,000-hp autogenous grinding mills for an iron ore project in Alaska. As if that weren't enough, they were going to dispense with the primary crusher and feed run-of-mine ore to the grinding mills which were to be driven by wrap-around seven-cycle motors. We see also that Bougainville Copper Co. will be grinding 90,000 tpd of ore in only eight 4250- hp ball mills. At Bougainville too, their float section will be the first large one to be completely equipped with the new 350-cu ft flotation cells. After a half century of relatively peaceful growth in the minerals industry, we are now seeing almost exponential advances in both equipment and plant size. At the same time, we are seeing a constant blending of hydro and pyrometallurgical techniques and processes into minerals beneficiation until the sample grind-'em-up-and-concentrate-'em plant is becoming a rarity.

Jan 1, 1970

By John W. Padan, John E. Crawford

Beginning with a small but positive participation in undersea mining, the Bureau of Mines continues its active investigations into this potentially tremendous field. The Bureau began its active role in undersea mining in September 1963, with a small task force of three dedicated scientists and a secretary, establishing headquarters at the old Tiburon Naval Net Depot about seven miles up the coast from San Francisco. The past months have been both busy and productive. With 22 Federal agencies involved in oceanography, it logically was the intent of Congress that the Bureau of Mines undertake research concerned only with the technology of marine mineral production and utilization. The Bureau has maintained this purpose in its activities at Tiburon, for while institutes, universities, the Navy and other Government agencies have developed exceptional programs in the fundamental science of the oceans, commonly called oceanographic research, little has been done toward advancing man's ability to exploit the ocean floors other than by drilling for oil and gas and sulfur.

Jan 3, 1965

By C. W. Davis

THE name fuller's earth, which was derived from its early use in "fulling" or removing grease from woolen goods, is a term that is generally considered to designate mineral matter, containing hydrous aluminum silicates of the clay group, which has a high capacity for removing colors from oils, whether of animal, vegetable, or mineral origin. Fuller's earths are usually dried and may be "tempered" by heating or may be treated with water or reagents to improve their efficiency. For our purpose the term "acid-treated earths" will include those products from the partial decomposition of mineral water -by acid which are equal to or more efficient than an untreated fuller's earth from Quincy, Fla., when used in bleaching mineral oil by the "contact" process. In general, the contact process for treating oils consists of heating and agitating a mixture of oil and finely divided adsorbent, the latter being subsequently removed by filtration. The term "adsorbent" is used because, although there has been a great deal of controversy over the mechanism of removal of impurities from oils by mineral matter, there is no doubt that adsorption, which involves the surface of the solid, plays a major part.1 The properties that make fuller's earth useful in the treatment of petroleum products by "percolation" and in the purification of edible oils by the contact process have long been studied, but the comparatively recent adaptation of the contact process to the bleaching of petroleum products has made desirable the further investigation of fuller's earth and other, adsorbent earths.

Jan 1, 1929

By A. U. Seybolt

A FEW copper-zinc-base alloys meet die-casting requirements reason- ably well, although improvements are desired. Aluminum bronzes, high-tinbronzes and some copper-nickel-zinc alloys can be die-cast, accordingto Herb,1 but seldom are because of such factors as higher melting ranges and greater cost than certain of the brasses. Fox2 has summarized the copper-base die-casting alloys that were in commercial use in 1937 and has given the effects of different alloying constituents. Table 1 gives some of the properties of these alloys as reported by Fox. TABLE 1. Commercial Die-casting Brasses a Constituent Yellow Brass Low-silicon High-siliconb Brass Brass Nickel Silver Composition, Per Cent Cu 57-59 63-65 80 -81.5 42.0 Zn 40-42 33-35 13.5-16.0 41.0 Sn 0.5-1.5 Si 0.75-1.25 3.75-4.25 Pb 1.0 Ni 16.0 Properties Tensile, lb. per sq. in.. 55,000-60,000 65,000-70,000 85,000-95,000 85,000-95,000 Yield, lb. per sq. in.d.. 30,000-35,000 35,000-40,000 65,000-70,000 65,000-72,000 Elong., per cent in 2 in . 15-20 20-30 8-12 10-20 Brinell hardness 120-130 120-130 160-180 160 Specific gravity 8.47 8.50 8.15 8.45 Properties reported by Fox.2 b Trade name of Brastil, Doehler Die Casting Co., similar to Webert Alloy, 3,4 American Brass Co., and Tombasil Alloy,5 Ajax Metal Co. c Trade name Tinicosil, Titan Metal Manufacturing Co. Melting point (liquidus) of the yellow brass is given by Herb' as 1650° F., of the high-silicon Brastil (with 4.5 to 5 per cent Si) as 1600° F., and of the nickel silver as 1675° F. d Criterion not stated.

Jan 1, 1939

Who's Who in Mineral Engineering - The 1978 Membership Directory of the Society of Mining Engineers of AIME

Jan 7, 1978

By AIME AIME

CORROSION of tanks, pipes and other equipment in the oil fields is becoming worse as the production of high- sulfur crudes in the Texas panhandle and west Texas areas increases. It has been estimated that .in certain fields of that State one tank out of every five has to be replaced every year because of the high sulfur content of the crude. One suggested method for combating tank corrosion is the use of .materials which have a high resistance to the corrosive action of hydrogen sulfide and high-sulfur crudes; aluminum is one of these materials. As a result, the United

Jan 1, 1929

By G. H. LeFevre

THE Metal Sales Department, with offices in New York, is responsible for the sale of the Company's products, with the exception of gold and coal. At present the department handles the sales of lead, zinc, silver, antimonial lead, , cadmium, bismuth, arsenic trioxide, and tellurium; gold is shipped direct to the United States Mint and coal is marketed by United States Fuel Company's own sales organization. The department keeps in close touch with the metal markets and collects information on marketing conditions, which it makes available to other departments of the Company. The electrolytic lead produced at the U. S. S. Lead Refinery, Inc., is a high-uality product marketed as corroding grade under the "U. S. S.-ELECTRO" brand. It is largely sold to manufacturers of paints, pigments, lead oxides, and storage batteries.

Jan 1, 1948

By AIME AIME

I am happy to welcome you to the twenty-third conference of the National Open-Hearth Committee, and our joint conference with the Blast Furnace Committee, of the American Institute of Mining and Metallurgical Engineers. It is appropriate that, for our fifteenth year anniversary, we should meet in the hotel and the city where this Open-Hearth Committee was inaugurated in 1925. At that first meeting, only a handful of men from a number of steel companies met to discuss ways and means to start a movement to improve the practical and metallurgical technique of open-hearth operations among independent manufacturers, as the United States Steel Corporation had carried on for many years.

Jan 1, 1940

By AIME AIME

COMMITTEES. CANAL ZONE.-Col. George W. Goethals, U. S. A., Chairman; Lt.-Col. H. F. Hodges, U. S. A. ; Lt.: Col. D. D. Gaillard, U. S. A. ; Lt.-Col. William L. Sibert, IT. S. A. ; H. H. Rousseau, U. S. N.; Col. W. C. Gorgas, U. S. A.; Maurice H. Thatcher ; Joseph Bucklin Bishop ; Lt.-Col. Charles F. Mason, U. S. A.; S. B. Williamson ; Major Eugene T. Wilson, U. S. A. ; Edward Schildhauer ; Henry Goldmark ; Edward C. Sherman ; W. G. Comber ; W. B. Corse ; J. A. Walker; Joseph A. Le Prince; J. A. Smith ; Lt. Frederick Mears, U. S. A. HAVANA.-V. T. Polledo, Chairman; Diego Lombillo Clark, Jose Primelles, J. R. Villalon, Jose Artola, J. Ducassi, Luis Morales, Enrique Montonlieu. ENTERTAINMENT ON SHIPBOARD.-William L. Saunders, Chairman; Mr. and Mrs. S. D. Warriner, Mr. and Mrs. Thomas Robins, Mr. and Mrs. George.D. Barron, Mr. and Mrs. R. B. Watson, W. E. Greene. GENERAL MANAGEMENT. .Joseph Struthers, Chairman; Albert E. Vaughan. There were ten sessions of the Institute held for the presentation and discussion of, technical or professional papers. Eight of these sessions were held on the steamer while en route, and two in the ball-room of the Hotel Tivoli, at Ancon, C. Z. Mr. David W- Brunton, President of the Council, presided at all the sessions, except the sixth, at which Mr. Charles Kirchhoff, past President, occupied the chair. The following list includes the papers presented in oral abstract by the authors: First Session., October 24. The Summit Hill Mine-Fire, by W. A. Lathrop, Philadelphia, Pa. Mine-Fire at the Calumet and Hecla Mine, No. 8 Shaft., by S. D. Warriner, Wilkes-Barre, Pa. Fire in the Big Lick Stope, Lykens Valley and Williamstown Colliery, by R. V. Norris, Wilkes-Barre, Pa. Mine-Fire in the Hecksherville Valley, Schuylkill Field, Pa., by W. J. Richards, Pottsville, Pa.. Fire in the Monarch Mine, near Rock Springs, Wyo., by S. A. Taylor, Pittsburg, Pa.

Dec 1, 1910

By Oliver Bowles

EACH year the broad diversified field of industrial minerals offers a panorama of new and interesting developments that not only concern the welfare of the industries themselves but have a more or less direct influence on the lives of citizens at large. Thus, the home life of multirudes may be affected by new building units that transmit light through walls instead of windows, by illuminated processed marble lighting fixtures and decorations, by the vast impetus given to thermal insulation Ly .mineral wool, expanded vermiculite, and related products, and, more remotely, by fireproof rugs and drap-

Jan 1, 1937