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By AIME AIME

DURING my senior year at college a professor said to his class that a student who failed to obtain a passing grade in that certain subject could not graduate with his class and that his diploma would be withheld until the failure had been removed. In that way for four years a diploma had been made to appear to us as the objective in attending college. We grew up to think that a diploma was the means of providing employment; consequently, a diploma could not be jeopardized and, heeding the professor's remarks, we resolved to put forth special efforts and make good. During one of our class periods this same professor digressed briefly from his prepared lecture in metallurgy and advised the boys to join a national technical society. He spoke with earnestness and sincerity. After class we students discussed those remarks. We concluded that the professor had not convinced us. We were already members of technical societies at school and saw no need of joining another. In fact, even up to that moment a society had never indicated to any of us that joining it had any relation to landing a job, and we were fully aware that joining another society meant paying out more money, for fees and dues, which money we then needed to buy food, clothes, and perhaps a new slide rule. Furthermore, we knew that joining a society was not part of the curriculum and, therefore, the diploma could not be withheld if we did not follow the advice. Our conclusion was that we would not join but would concentrate on our work that assured getting our diplomas.

Jan 1, 1936

By C. G. Dunn, F. W. Daniels, M. J. Bolton

Recent observations on grain boundary movements in sihcon iron have indicated the possibility of studying grain growth phenomena in two-grain specimens in which several variables affecting growth are readily controlled. These variables are (1) the energy per unit area (?) in the grain boundary, (2) the orientation relationship of the two grains, and (3) the radius of curvature (7) of the moving boundary. Ideally, one grain A should be a narrow rectangular parallelepiped adjacent to a second grain ß as shown two dimensionally in Fig 1. Such a two-grain group becomes unstable when one end of grain A is shaped according to the dotted line. Since the width w of grain A remains constant during growth of grain B, T should also remain constant. The other vari- ables mentioned above can be controlled in the preparation of each two-grain specimen.l,2,3 For a parLicular orientation of each grain, is not necessarily fixed; ? may also depend on the orientation of the grain boundary, but this may be controlled to some degree. The energy relationships for the gowth of grain ß may be derived from the more simple arrangement of two grains A' and B' shown schematically in Fig 2. Here B' largely surrounds A'. Assume these grains are oriented with a common plane parallel with the flat

Jan 1, 1950

[Trans. No. Place Date Vol. Page 1. Wilkes-Barre, Pa May, '71.. 1 3 2. Bethlehem, I's Aug., '71.. 110 3. Troy, N. Y Nov., '71.. 113 4. Philadelphia, PaFeb., '72.. 117 5. New York, N. YMay, '72120 6. Pittsburgh, Pa Oct., '72.. 125 7. Boston, MassFeb., '73.. 128 8. Philadelphia, Pa.*May, '73.. 23 9. Easton, PaOct., '73.. 27 10. New York, N. Y Feb., '74211] [ ]

Jan 1, 1925

By P. M. Robinson, J. S. LI. Leach

The heats of solution oj' indiurrr, tin, lend, nrzd tellurium have been calculated from the measured heat effects when mechanical mixtres of indium and telLuium tin and tellurium, and lead and tellurium were added to liquid bismuth. The results are in good agreement xith publislzed values.s for the separate sollction of each eleltzent in bismuth. The heats oj solution of cadmium and tellurium calculated from the rneasuved heat effects on adding trechanical mixtures of these elements do not ugree zc,itl the published values jbv the separate solution of each element. It is shown that at 623°K Ile interaction between cadmium and tellurium dissolved in liquid bismuth is strong enough to led lo preciPitation of solid CdTc. The heats oj- jor-mation of CdTe at 273" nd 623°K (1)-c crilculated fi-or the measured heat ejlfecls. The calcnlaled az'erage deviation from the Kopp-l\'ez?,zunrz rule fov solid CdTe is less than 0.06 cat per g-atom- C over this lertzperalure range. Tlze importance 0.f these oDserl.ations to the determination of heals of formation hy metal solution calorimetry is considered. LIQUID metal solution calorimetry is a convenient method for determining the heats of formation of solid compounds. In this technique the heat of formation is the difference between the measured heat effects on dissolution of the compounds and of mechanical mixtures of the components in the liquid metal.' The heat of solution of the mechanical mixture may be calculated from the measured heat effect. At infinite dilution of the solutes, this heat of solution is equal to the sum of the heats of solution of the separate components. If the heat of solution of one of the components is known, the value for the other can be derived; if both are known, they may be used to check the accuracy of the calorimetric technique. The heats of formation of the tellurides of cadmium, indium, tin, and lead have recently been measured by metal solution alorimetr. The heats of solution of indium, tin, lead, and tellurium at infinite dilution in liquid bismuth at 623"K, calculated from the measured heat effects on solution of the mechanical mixtures, are in good agreement with the published values. The heats of solution of cadmium and of tellurium calculated from the measured heat effect on solution in bismuth at 623'K of mechanical mixtures of cadmium and tellurium, however, do not agree with values estimated from the literature. 1) EXPERIMENTAL PROCEDURE AND RESULTS The Heats of Solution of Indium, Tin, Lead, and Tellurium in Bismuth. The heat effects were measured when mechanical mixtures corresponding to the compounds In,Te, InTe, In2Te3, In2Te5, SnTe, and PbTe were dissolved in bismuth. The calorimetric procedure and the method of calculation have been described elsewhere.' The heats of solution of the mechanical mixtures were obtained by subtracting the change in heat content per gram-atom of the sample between the addition temperature (273°K) and the bath temperature (623"K), (H623°K - H273°K)S, from the measured heat effects. The calorimeter was calibrated with pure bismuth. The reported values of the measured heat effects are based on (HGoK - ^273oK)Bi = 4.96 kcal per g-atom.3 The measured heat effects are found to be linear functions of the solute concentrations of the bath in the dilute solution range. The values, extrapolated to infinite dilution, are listed in Table I, together with the heats of solution of the mechanical mixtures calculated using the published values of (H 623°K - H273°k)s for indium, tin, lead,3 and tellrium. All the error limits quoted in this work represent the spread of values obtained. The heats of solution in liquid bismuth at 623°K of mechanical mixtures of indium and tellurium in four different proportions were determined. Values of the heats of solution of the two components were then calculated from the resulting four simultaneous equations: The heats of solution at infinite dilution of tin and lead in liquid bismuth at 623°K were calculated from the heats of solution of the mechanical mixtures of tin and tellurium and of lead and tellurium using the heat of solution of tellurium calculated above. These values of the heats of solution are listed in Table I1 together with some published values for comparison.

Jan 1, 1967

By Roger L. Beals, George A. Tweedy

The results of the cyanide-operations, given in detail in the following paper, show the progress that is being made at the Minas del Tajo. The old pan-amalgamation process, in operation up to and including 1905, while paying a profit on high-grade ores, was no longer able to treat profitably the ores in sight at that time; hence an alteration in the process was imperative. The success of this alteration is eloquently expressed by the following data : Pan-Amalgamation. Cyanidation. 1905. 1905. " 1908. Tons treated,.... 51,387 58,983 69,200 Value per ton (U. S. currency),. $ 10.78 $8.39 $8.28 Extraction, per cent.,.. 65.00 88.56 87.45 Extraction, per ton,.. $7.00 $7.43 $7.24 Total cost, per ton treated, . 6.50 4.36 4.01 Profit, per ton treated,.. 0.50 3.07 3.23

Jan 1, 1911

By HENRY M. HOWEL

1. Introduction.-The first part of this papers treats of the causes and the restraining of piping in steel ingots; the second& considers the causes and the restraining of -segregation; and the third proposes certain precautions in engineering specifications concerning these two defects. Into their causes I have looked carefully, with the purpose of arriving at rational methods of restraining them, and at efficient ways of detecting. and measuring the harm which they cause, so as to benefit the public by reducing this harm at once effectively and with the least expense to the manufacturer, and therefore in the end with the least expense to the consumer. In Part I., I infer that the pipe is chiefly due to what I, call the virtual expansion of the outer walls of the ingot in the early part of the freezing. I find that the upper and smooth-faced part of the pipe probably forms while the interior is still molten, but that the lower, steep, and crystal-faced part probably forms in metal which is already firm. Of the five causes which may co-operate to limit the depth of the pipe, I find that three-blow-holes, sagging, and the progress of freezing from below upwards-are usually effective. I find that the pipe may be lessened by casting (1) in wide ingots,; (2) in sand molds, especially if these are pre-heated (this is rarely expedient); (3) at the tops instead of at the bottom; (4) slowly; (5) and with the large end up; (6) by the use of a sinking-head or other means of retarding the cooling of the top; (7) by permitting blow-holes to form; and (8) by liquid compression.) Most of these I consider in some detail, and in particular I dwell on the advantages of casting with the large end up, and I propose certain administrative arrangements to permit this.

Mar 1, 1907

By Irwin H. Cornell

BRIEFLY stated, the history of the St. Joseph Lead Co. is the story of how a group of men, working for ten years as officers without salaries and stockholders without dividends, developed a small mine in Missouri into what became a large and prosperous corporation. Their courage and faith in the scattered surface deposits of lead coupled with the management's engineering vision and sound financial judgment should prove an inspiration to present-day mining operators and investors. In 1717, John Law's company, known as "The Company of the West," was formed in France and letters patent were granted, for a period of 25 years by Louis XV, for exploration in the Mississippi River Valley. One of the underlying purposes of the expedition, headed by Mr. Renault and Mr. La Motte, a French metallurgist, was development of the lead mines in the area now known as Southeast Missouri.

Jan 1, 1947

By Walter Knox, J. D. Doherty

IN 1939, at the request of The Koppers Coal Co., the Koppers Company Research Department established a Stoker Coal Research Laboratory for the purpose of investigating the performance characteristics of stoker coals in typical domestic stoker installations. Fig. I is a photograph of part of the laboratory. The material in this paper deals with the performance of one coal in a single installation. Presented are details of this installation, mechanical characteristics of the stoker, and the results of a series of burning tests in which adjustments were systematically varied. SUMMARY OF RESULTS Mechanical Features I. A large percentage of the total power consumed by a domestic stoker is used to operate the gear case and motor (Fig. 3). 2. The power consumption per ton goes down with an increase in rate of coal feed (Fig. 4). 3. The automatic air control in this stoker showed advantages over manual control (Fig. 5). 4. The air velocities through the retort tuyeres were uniform around the retort, but varied between the rows of tuyere rings (Fig. 6). 5. The crushing of coal with this stoker increased the minus 1/8-in. from 1 1.6 per cent to 19.2 per cent. There was a noticeable segregation of coal as it came from the retort and distribution was not uniform (Fig. 7). 6. Measurement of air entering over the fire showed that with some not uncommon adjustments this air may he a high percentage of the total air supply (Fig. 8 and Table I). Operating Performance I. The removal of clinker was shown to give a period of poor performance characterized by a high fuel-bed resistance and a high percentage of carbon monoxide in the flue gases (Fig. 10). 2. The fuel-bed resistance was found to decrease as the fuel bed built up in a normal response to heat demand after a prolonged hold-fire (Fig. II). 3. With intermittent operation the burning rate was almost always less than the feeding rate. The wide variations were found to be greatly dependent upon the length of the On period and the length of the intervals between On periods (Fig. 12). 4. The maintenance of a low furnace draft led to less fly ash, better clinker formation, and higher efficiencies (Fig. I3). 5. The maintenance of a minimum of excess air also resulted in less fly ash, better clinker formation, and higher efficiencies (Fig. 14). GUIDING PRINCIPLES In planning the investigations, the following principles were adopted: Selection of Healing Equipment.-Use only standard models of stokers and furnaces representative of those widely used.

Jan 1, 1942

By Oscar A. Glaeser

INDUSTRIAL relations in the United States Smelting Refining and Mining Company's Western operations covers the field of personnel and labor relations, and the principal aims are to render service to the employes of the Company and to its operating departments. Accident prevention Safety is a primary function. A safety engineer is employed at each operation. The wholehearted support of Company officials, staff, and the working force has been most successful in preventing accidents. Constant vigilance has been combined with a policy of building safety into all operating activities whether these are in the construction of a new facility, the developmnt of a mining system, or the direction of the working force. That this policy has produced results is attested to by the fact that the accident frequency rate at the Company's major mining operations in Utah has been reduced approximately 75 per cent in the ten-year period ending Dec. 31. 1946.

Jan 1, 1948

By R. G. Davies

The activation energy for steady state creep above -500°C is observed to be independent of the applied stress although it varies from -67 kcal per mole at 2 at. pct Si to -100 kcal per mole at 11 at. pct Si due to changes in crystallographic order. The magnitude of the activation energy, by comparison with Fe-A1 alloys, indicates FeSi type of order in certain alloys. X-ray results confirmed the presence of FeSi type of order. It is proposed that dislocation climb is the rate controlling mechanism for all the alloys. It has been demonstrated that when a diffusion mechanism is the rate controlling process, the formation of a superlattice in brass,1 Fe3A1,2 Ni3Fe,3-5 and Feco6 1) increases the creep resistance, and 2) increases the activation energy for steady state creep. Furthermore, a study of creep in Fe-15 to 20 at. pct A1 alloys7 has revealed that as the alloy composition approaches the long-range order field, there is an increase in the activation energy for steady state creep which is thought to be due to an increase in short range order. Fe-A1 and Fe-Si alloys are similar in that they both form the DO3 superlattice in which aluminum or silicon atoms have only iron atoms as first and second nearest neighbors. There are, however, two important differences between the alloy systems: 1) The superlattice formation at -350°C commences at -10 at. pct si8 as compared to -20 at. pct Al,9 and 2) Fe-A1 alloys form a FeAl (B2 type) super-lattice where aluminum atoms have all iron first nearest neighbors even at 22 at. pct Al, but so far no similar FeSi superlattice has been observed. With the similarity between Fe-A1 and Fe-Si alloys in mind, alloys of iron with 2 to 11 at. pct Si were examined for variations with composition of the activation energy for steady state creep and of creep strength. The temperature range of greatest interest was above 1/2 TM (TM is the absolute melting temperature) where it is usually observed that diffusion is the rate controlling process. A subsidiary X-ray investigation of the Fe-Si system was undertaken in an attempt to define the position of the order-disorder boundary as a function of cooling rate. EXPERIMENTAL DETAILS a) Creep. Specimens whose gage length was 1.5 in. and with a cross-section 0.04 by 0.08 in. were strained in tension by a lever-arm arrangement, and the load was adjusted between each creep test to maintain constant stress. The apparatus and mode of operation have been fully described in a previous publication.7 As each test produced a creep strain of 0.25 pct, the variation in stress during the test was negligible. Creep strain was measured at the end of one of the alloy steel grips by a displacement transducer with the out-of-balance potential being recorded on a variable speed recorder. The full-scale deflection of the recorder could be varied in steps to give limits of sensitivity of between 0.1 and 0.001 pct creep strain. The alloys, Table I, were made available by the Metallurgical Department, National Physical Laboratory (N.P.L.), england,10 and by the Research Department, General Electric Co. (G.E.), Schenectady, N.Y. They were hot worked at -850°C, warm worked at 550° to 650°C, and recrystallized in vacuum at -750°C to give a grain diameter of -0.1 mm. All the alloys had a very low impurity content; those from the N.P.L., for which a complete analysis is available,&apos;&apos; show carbon less than 0.026 pct, manganese less than 0.006 pct, and oxygen plus nitrogen less than 0.0024 pct. b) X-ray Procedure. A General Electric XRD-5 X-ray set with a focussing lithium fluoride mono-chromator in the diffracted beam, and a pulse height analyzer to eliminate harmonic wavelengths of the cobalt radiation, was used to investigate the structure of several very fine grained (grain diameter <.01 mm) Fe-Si alloys after the following heat treatments: 1) Quenched from 700°C, 2) slow cooled from 650°C (-40°C per hr), and 3) very slowly cooled from 400° to 100°C (10°C per hr with a 24 hr anneal every 100°C). The method of obtaining the diffraction pattern over the range of 20 from 15 to 45 deg was to count for at least 100 sec every l/3 deg with a slit subtending 1 deg in 20 at the focus; the probable counting error was less than 2 pct.

Jan 1, 1963

NEW YORK SECTION ALLEN H. ROGERS, Chairman, H. C. PARMELEE, vice-chairman, FOREST RUTHERFORD, Vice-chairman, W. S. DICKSON, Secretary, 71 BROADWAY, NEW YORK, N. Y. J. E. JOHNSON, JR. F. T. RUBIDGE, Treasurer, P. G. SPILSBURY A meeting of the New York Section was held at The Machinery Club on Friday evening, Oct. 4, 1918, The Chairman, Allen H. Rogers, presiding. The CHAIRMAN.-MOST of us, I suppose, have been affected more or less by The request of The Fuel Administration that we leave our automobiles standing in The garages on Sundays. We shall all be interested in hearing about The situation that has called forth This, request, and The Oil Administrator, Mr. Requa, has kindly come from Washington to Tell us about it. MARK L. REQUA.-I am very glad To Tell you about the oil problem during This war period. The United States is supplying by far The greater part of all The petroleum products consumed in Great Britain, France and Italy. In addition To This, we have had To supply a marked increase in our domestic consumption, not only of The refined products, but of fuel oil as well. The combination has put a strain on The oil industry, which it is very difficult To meet. The oil companies, being under contract, had no option as To who should get Their oil first, and They were delivering pro rata To everybody; manufacturers of furniture were getting oil with The same regularity as Those who were making aeroplanes or munitions, and The oil companies felt that something should be done. The first order with which I had. anything To do was The priority list for The delivery of fuel oil. That list contained 12 classifications, beginning with bunker fuel and railroads, and you will realize The complexity of The situation when you hear that munitions plants are in class 11. The priority list held during The winter, but transportation became so bad, because of The number of ships that were Taken for trans-Atlantic use, that some of The oil companies were not able To deliver more Than about 60 per cent. into class 5, and nothing beyond that point. To add To the Troubles, the Tank-car mileage fell off. The average for 1917 was about 36 miles per car per day. in January, 1918, it dropped To about 8 miles, and it must have been nearly zero in The early part. of February. Because of The extremely severe winter, furthermore, pipe lines were not delivering anywhere near Their normal capacity. A new priority list has recently been promulgated, introducing a few slight changes. Natural gas has been brought under its provisions, and it has been extended To include The Pacific Coast, which was not considered necessary last winter. The situation in The gas industry is not satisfactory; it is estimated that There will be a decrease of 10 To 20 per cent. in The quantity of natural gas available This winter, as compared with last winter.

Jan 11, 1918

[Separates of all the Pamphlets published within the last three years (starting with No. 1469) are available, with few exceptions, at Institute headquarters. Separates of all the Technical Publications are also available. All the papers are on file in public, university and technical libraries, and when so indicated in the list, may be found either in the TRANSACTIONS or in the special volumes issued by the Institute.] METAL MINING TRANS. PAMPHLET VOLUME NUMBER TITLE AUTHOR MEETING AND PAGE* -1033 Relation of Air Pressure to Drilling H. W. Seamon New York 66,743, 766 Speeds of Hammer Drills Feb., 1921 1034 Time Factor in Depletion of Mines J. W. Roberts New York - 66,711 Feb., 1921 1 1035 Calculation of Ore Tonnage and Grade J. E. Harding New York 66, 117, 122 from Drill-hole Samples- Feb., 1921 1038 Discussion of Papers Presented in 1920 1041 Run-off and Mine Drainage - H. N. Eavenson New York 66, 624, 630 Feb., 1921 1043 The Health of the Underground Worker A. J. Lanza New York Feb., 1921 1045 Dust-ventilation Studies in Metal D. Harrington New York 66, 272, 282 Mines Feb., 1921 1046 Discussion of Papers Presented at New York Meeting, 1921 1072 Breakage and Heat Treatment of Rock- B. F. Tillson New York 66,758 drill Steel Feb., 1921 1073 Discussion of Papers Presented at New York Meeting, 1921 1076-M Analysis of Some Drill-steel Tests F. B. Foley New York - 66,789 Feb., 1921 1077-M Application of Magnetic Analysis to C_ W. Burrows New York 66,796 Root Drills Feb., 1921 1078-M Heat Treatment of Rock-drill Steel G. H. Gilman New York 66,779 Feb., 1921 1080 What is the Ideal Drill Steel? F. H. Kingdon New York 66,807 Feb., 1921 1081 Rock Drill Steels, etc. W. T. Ober New York 66,814 Feb., 1921 1082-C Underground Mine Development, Its J. B. Dilworth Wilkes-Barre 66, 715, 721 Definition and Valuation Sept., 1921 1084 Drill Steel from Hollow Ingots P. A. E. Armstrong New York 66,809 Feb., 1921 1088 Authors&apos; Replies to Recent Discussion 1092 Heat Treatment of Rock Drill Steel A. E. Perkins New York 66,811 Feb., 1921 1096-M Octagonal Ventilation Shaft of Davis- J. L. Bruce Wilkes-Barre 66, 252, 268 Daly Copper Co. Sept., 1921 1100-C Determination of Electrical Equip- G. Bright Wilkes-Barre 66, 580, 605 ment for a Mine Hoist Sept., 1921

Jan 1, 1926

By James R. Finlay

SOMETIMES the American Institute of Mining and Metallurgical Engineers appears to be a strictly technical society, and if so my paper should deal with the technical operations of finding and producing gold. But I have not been engaged in practical gold mining since 1910. What I have been doing mainly for the last 25 years is to try to figure out what the income of a mine-gold, or any other-would be worth to an investor. So I have been in contact with gold mining, in one way or another, for some 42 years. I say that with a purpose. In that time the industry has been through one of its cycles. The value of gold mines is very dif¬ferent at different points in one of these cycles. For this reason the cycle of gold mining is a highly practical study. The cycle of gold is a more or less rhythmical change in its value or purchasing power measured in the grand average of other commodities, which is the same thing as its price. Taking the price of gold in 1897 as a stand¬ard, a dollar at that time declined to 55c. in 1913, to 26.8c. in 1920, and since then it has risen to 47.4c. in 1930 and to about 64c. in 1932. It is worth about 21/ times as much now as it was in 1920, but less than two¬thirds as much as in 1897. When this change is applied to the value of a gold mine still greater differences are evident. The cost of producing gold is of course measured in labor and other commodities, and as that cost goes down the margin of profit measured in the gold itself increases. Thus a mine which might make only 10 per cent profit in 1920 on its gross output may easily make 25 per cent now. The stockholder gets 2 ½ times more gold that is worth 2 1/2 times as much in purchasing power, therefore the real value of his holding has risen by the one factor multiplied by the other, giving him 61/4 times as much goods or services as he had in 1920.

Jan 1, 1933

By T. C. Russell

The Conda phosphate mine, eight miles north of Soda Springs in Caribou County, Idaho, was opened up by the Anaconda Copper Mining CO. in 1920. Except for brief periods, during the 20&apos;s and early 30&apos;s, the mine has maintained a continuous production, and 2,100,000 short tons of phosphate rock have been shipped to the company&apos;s phosphate fertilizer manufacturing plant at Anaconda, Mont., or to independent processing plants on the Pacific Coast; a small tonnage of the rock has been shipped to the Hawaiian Islands. The Phosphoria formation on the Conda property consists of two, commercial-grade phosphate beds separated by 147 ft of black to brownish colored phosphatic calcareous shales interbedded with softer mudstones, clays, and occasional narrow seams of oolitic phosphate. The main lower phosphate bed in the series averaging 7.1 ft in thickness, is called the "foot-wall bed," which lies coriformably on the Wells limestone formation, the 1atter often containing irregular bands of chert. The upper or " hanging-wall bed" of phosphate rock averaging 7.2 ft in thickness, is overlaid by thick quartzite beds, locally called the " Rex chert" member in the upper portion of the Phosphoria formation. (Fig 1.) There are two anticlines on the property with axis striking approximately parallel to the mountain range beneath which extensive development on phosphate rock has been conducted in the past, and is now in progress. The phosphate beds have been eroded to a large extent from the tops of these anticlines, leaving at least three well-pronounced outcrops of the phosphate beds exposed within the boundaries of the Anaconda Copper Mining Cornpany&apos;s properties. At present, mining operations in the Conda No. 3 mine are confined to the two phosphate beds along the east flank of the easternmost anticline, where the dips on the beds vary from 50° to 60° east, thereby affording favorable conditions for the sublevel mining system now in use. Mining operations formerly were confined to the footwall or lower oolitic phosphate bed because of its higher phosphate and vanadium contents (32 pct P²O5 and 0.29 pct V2 O 5); this bed averages 7.1 ft in thickness. The oolitic portions of the upper bed were of satisfactory grade, but the shale and clay partings (Fig 2) diluted the mined rock and could not he separated economically by selective mining or by sorting. Experiments in beneficiating this rock were carried on for a number of years. Recently, a simple washing process was adopted, which gave a satisfactory grade of concentrates and a high recovery of P² O5. In 1947 it was decided to expand Anaconda&apos;s production of treble superphosphate and phosphoric acid by approximately 90 pct. This rock will be obtained from the footwall and hanging-wall beds, and the rock from the hanging-wall bed will be benefici-ated at -Anaconda.l In order to take advantage of the previous development on the 500 secondary haulage level, short crosscuts will be driven at approximately 950 ft intervals from the existing lateral drifts through the hanging-wall shale beds. From the inner end of each crosscut, short lateral drifts will he driven in both directions, so that four working raises can he put up on the dip of the phosphate bed at proper intervals along each of the lateral drifts. The mining operation on the footwall bed at Conda

Jan 1, 1950

By M. D. Banus, M. B. Bever, A. K. Jena

The heals of formation at 78", 195, and 273°K of the ternary compound h3SbTe2 based on the elements and based on the binary compounds In Sb and [inTe have been measured. The heats of formation at these temperatlcres of the binary compounds In Sb and In Te based on the elements have also been determined. Heal contents and free energies of the three compounds have been calculated from 0° lo 80I)°K. The free energies of joyrrzalion, heats of formations, and entropies of formation at 298°K have also been calculated. The results shown that the tertnary compound is metastable with vespecl to InSh and ln Te below 696 °K. bul is slable above that temperature. The weaker bonding of results in a positice entropy of formation which with incrensirzg temperature makes increasing negative conlvihtclions to the free energy and above 696°K renders the compound slable. THE ternary compound In3SbTez occurring in the quasi-binary system In Sb- In Te&apos; forms on cooling at 829°K by a peritectic reaction.&apos; Observations at 673" and 573 K have shown that this ternary compound decomposes slowly into the binary compounds InSb and1n~e.l&apos;&apos; It has not been possible to analyze the metastable behavior of the ternary compound because up to the present time data on its thermodynamic properties have been lacking. Some information on the binary compounds, however, is available. The heat of formation of InTe at 273°K and its free energy at 673°K are kn~wn.~&apos;~ The heats of formation of InSb at 78", 273&apos;, 298", and 723°K have been measured5-&apos; and its heat capacity between approximately 12" and 300"Kg9l0 is also known. In the investigation reported here the heats of formation at 78% 195% and 273°K of the ternary compound In3SbTez have been measured. The heats of formation of the binary compounds InSb and InTe at these temperatures have been obtained by combining new calorimetric results with previously published data. The heat contents and free energies of the three compounds at various temperatures from 0" to 800°K have been calculated. Against the background of this information, the metastability of the ternary compound will be discussed. 1) EXPERIMENTAL 1.l) Preparation of Specimens. The materials used consisted of the elements indium, antimony, and tellurium, the binary compounds InSb and InTe, and the ternary compound In3SbTez. The elements, obtained from American Smelting and Refining Co., had a nominal purity of 99.999+ pct. The compound InSb was Cominco semiconductor grade; the compound InTe was prepared from the elements by melting under a vacuum of 10-h m Hg followed by slow cooling. Three batches of specimens of the compound In3SbTez were used. One batch was prepared by melting appropriate amounts of the elements in an evacuated and sealed Vycor tube. The melt was held at approximately 100°K above the liquidus for about 8 hr, shaken repeatedly, and quenched into a mixture of ice and water. The specimen was annealed in vacuum at 760°K for 4 weeks. In preparing a second batch, a mixture of the component elements was melted and quenched in water. The resulting ingot was powdered. The powder was pressed into pellets, which were annealed in vacuum at 748" to 773°K for 4 weeks. A third batch was prepared in the same manner as the second, except that the starting materials were InSb and InTe rather than the elements. Metallographic examination of samples of the three batches and X-ray diffraction examination of a sample of the second batch did not reveal evidence of microsegregation or a second phase. The results obtained with the three batches showed no systematic differences. 1.2) Calorimetry. The calorimetric method has been described in detail." Samples of the compound In3SbTez, mechanical mixtures of InSb and InTe in the proportion of 1:2, and mechanical mixtures of indium, antimony, and tellurium in the proportion of 3:1:2 were added to a bismuth-rich bath at 623°K in a metal-solution calorimeter. These additions were made from 78°K (liquid nitrogen), 195°K (dry ice and acetone), and 273°K (ice and water). The heat effects of the additions were measured. The difference in the heat effects of the additions of a compound and the additions of the mixtures of its constituents, adjusted for differences in the concentration of the bath, is the heat of formation of the compound. In the concentration range not exceeding 1.5 at. pct solute, the heat effect of the additions was a linear function of concentration. The heat of formation refers to the temperature from which the additions were made, namely, 78", 195", or 273°K. Several calibrating additions were made in each calorimetric run. The calculated heat capacity of the calorimeter and hence the calculated heat effects of the additions of samples depend upon the values adopted for the heat contents of the calibrating substance. In this investigation bismuth at 273°K was used and a value of 4.96 kcal per g-atom was taken for (HGZ3"k . 2) RESULTS AND DISCUSSION 2.l) Heats of Formation. The heats of formation of the ternary compound In~SbTez from the component elements indium, antimony, and tellurium and from

Jan 1, 1968

By G. M. Ikeda, J. G. Sibakin

An investigation was carried out to determine the variables affecting the coiling temperature of strip in the 56-in. hot strip mill. After statistical treatment, equations have been derived to determine the temperature drop between mill and coiler for both full spray (top and bottom) and top spray only practices. The individual influences of each variable in the temperature drop were derived for both practices. Limitations of the present practices were shown and adjustments in cooling for increased rolling speeds were suggested. A method of estimating the required number of sprays, their spacing, pressure, etc., to achieve a desired temperature drop is developed. MAXIMUM finishing temperature of a hot strip mill is mainly determined by the rolling speed, gage, and the temperature of the bar entering the mill. This finishing temperature may be limited by the maximum admissible coiling temperature in cases when either the cooling facilities on the runout table are not adequate or, more generally, when the cooling capacity of the runout table and the production capacity of the continuous mill are out of balance. Some time ago, the balance between these two factors was not considered detrimental to production. Recently, a new drafting schedule was introduced which increased the production rate, the entry temperature, and hence the finishing temperature. Thus, the restriction of the maximum specified coiling temperature became an important factor for many of the thicker gages. An investigation of the factors determining the coiling temperature may be, therefore, of considerable importance. A brief description of the available equipment will be a useful illustration of the techniques and methods used for this investigation. The 56 in. continuous hot strip mill is composed of six 4-high stands each containing two 221/2-in. diam work rolls and two 45-in. diam back-up rolls. Either of the last two stands can be used as the finishing stand. Which stand is used is dependent on the total percentage of reduction to be taken over the whole train, i.e., on the entry thickness and the final gage. The characteristics of these last two stands are given in Table I. Table I. Operational Characteristics of Nos. 5 and 6 Stands No. .5 NO. 6 Maximum voltage GOO 600 Power, hp 30(10 W00 I normal, kilonmp 4.35 3.73 Rpm of motor and rolls ISO 15 0 ITS to 300 Spettl ot strip, fpm 333 6 to 376T.2 103) to 2062 The speed of the finishing stand varies with the amount of reduction, strip width, and the exit gage. Finishing speeds in general use for varying gages are shown in Table 11. These speeds may change with an increase or decrease in the entry temperature of the strip. Even though the maximum speed of No. 6 stand is shown as 2062 fpm, this has so far never been attained,

Jan 1, 1957

By Edward H. Robie

PROBABLY nowhere in the United States or its possessions is mining development more active at present than in the Philippine Islands. Only a few years ago only one company was of any importance, the Benguet Consolidated. Now, five companies are paying dividends, five others have reached the producing stage, some seven others may produce this year, and a score or so are being actively developed. Gold production in 1933 was valued at about $8,000,000, last year at about $11,000,000, and this year an output valued at about $17,000,000 is envisaged. At the beginning of 1934 about 1750 tons of ore was being milled daily; at the end of the year, the tonnage was approximately 3400. In 1933 there were only thirteen Institute members in the Philippines; a year ago there were 27, and now there are 46. About fifteen thousand amen were employed in the mining industry last year, with mine payrolls amounting to $3,500,000. An immense amount of new machinery has been required. One difficulty has so far hindered gold-mine development to some extent-lack of adequate power. Each company therefore finds it necessary to generate its own power, and for this purpose diesel engines are generally adopted.

Jan 1, 1935

By B. D. Lichter

The lattice parameters of zirconium and zirconium-oxygen solid solutions (hcp) were determined from measurements of back-reflection X-ray photograms obtained at 29°C using a symmetrical focussing camera. The following linear equations between parameters (c,a) in angstrom units (10-8 cm) and atom ratio (m) of oxygen to zirconium were obtained: c = 5.14764 + 0.2077m a =3.23168 + 0.1099m. The linear equations given are valid over the range 0 to 5 at. Pct 0. The accuracy of individual parameter measurements approaches the limiting accuracy determined by the spectral broadening of the incident characteristic radiation, and exceeds the accuracy of previously reported values. THE present work was undertaken in order to determine the lattice parameters of zirconium-oxygen solid solutions with an accuracy that allows quantitative determination of oxygen in zirconium. The results indicate that this is possible if very careful measurements are made, since the parameter change is only a few hundredths of a percent per at. pct 0.1, 2 In the present investigation the desired accuracy was achieved with large-grained samples using a back-reflection focussing camera and maintaining good temperature control during exposure. In addition a digital computer was used for calculation of the parameters by means of an analytical extrapolation.37 Suitable diffraction photograms were obtained from large-grained samples by using a modification of the technique described by Graf and Monteil.5 This consists of simultaneous rotation and oscillation of the specimen about two mutually perpendicular axes during exposure. Whereas, normally the upper limit of grain size is about 50 µ for useable diffraction photograms, this technique allows extending the upper limit of grain-size to exposure of a single crystal. EXPERIMENTAL Preparation of Alloys for X-ray Diffraction—Zir-conium, designated as hafnium-free, Westinghouse "Grade 1," was swaged from l/2-in.-diam crystal bar to 3/8-in.-diam rods. Substantially all of the hydrogen was removed from the zirconium by annealing at 1200°C in a high dynamic vacuum. The rods were then swaged to 0.2 in. diam without intermediate annealing, and 2 in. lengths were cut for alloying with oxygen. Samples for chemical analysis were taken from portions of the rods between each 2 in. length. Chemical analysis of the dehydroge-nated zirconium is given in Table I. Commercial tank oxygen (99.5 pct 0) was condensed in a liquid nitrogen-cooled trap, and part of the condensate was slowly reevaporated into 5-liter storage flasks. Nitrogen remained as a reactive impurity, and the calculated maximum increase in nitrogen content after a 5 at. pct 0 addition to zirconium was 50 ppm by weight. However, chemical analyses of several of the prepared alloys indicated that the maximum increase in nitrogen content was 10 ppm. The storage flasks, a Sieverts-type gas burette and manometer, and associated traps, pumps, and pressure gauges were connected through a glass high-vacuum manifold to comprise the gas addition system. A fused silica tube, connected to the mani-

Jan 1, 1961

By R. G. Davies, R. H. Richman

Several techniques, X-ray diffraction, transmission electron microscopy, conventional, metallography, and mechanical property measurements are combined to investigate decomposition in the suPersaturated solid solution Fe-27 at. pct Be. The following sequence of structures for aging temperatures below 400°C is established: massive short-range order, pseudo-FeBe (L2o) order, Fe3Be (DU3) order, sinusoidal modulation of composition, general or continuous precipitation, and discontinuous or cellular precipitation. In addition to this sequence itself, several features of the individual stages are noteworthy; for example, when coherent modulations occur, their development is parallel to (100) everywhere in the specimen apparently without incubation, and both the wavelength and the composition amplitude of the modulations increase with aging time. Two types of discontinuous reaction are observed, depending upon the aging temperature. At low temperatures (<550°C) the boundary-nucleated variety of discontinuous precipitate predominates; but at higher temperatures (>600°C) the crystallographic variety occurs instead. Hardness and flow-stress measurements clearly reflect the quoted structure sequence. Some qualitative aspects of the structure changes and of the relationship between mechanical properties and structure are discussed. BERYLLIUM in solid solution markedly strengthens iron.&apos;" A recent study demonstrated that not only were supersaturated single crystals of Fe-27 at. pct Be very strong, but they deformed primarily by mechanical twinning.3 Such behavior, coupled with the decrease in solid solubility of beryllium in a Fe from about 33 at. pct at 1165°C to about 10 at. pct at 500°C4 as shown in Fig. 1, leads naturally to questions about property changes with aging in this system. In 1929 roll,1 and later Seljesater and Rogers,5 reported that useful increases in strength could be obtained by aging quenched Fe-Be alloys, but it was not until quite recently that any of the details of precipitation in these alloys were studied. Richman6 observed that both an Fe3Be superlattice (with a DO3 crystal structure the same as Fe3A1, illustrated in Fig. 2) and a modulated structure preceded the appearance of a discrete second phase in the 20 at. pct Be composition. Here, a modulated structure refers to a periodic composition fluctuation within one crystal, while its lattice remains coherent. Subsequent work on a Fe-Be alloys by Heubner7 and von Heimendahl and Heubner8 confirmed the existence of the modulated structure, although only an FeBe (L20) ordered structure was detected (also shown in Fig. 2). Both Rich-man and Heubner corroborated the large increases in hardness during aging reported earlier, but other mechanical properties were not examined. Since modulated systems are encountered relatively infrequently, the influence of coherent modulation upon mechanical properties is not well-known. With the accumulation of information about age-hardening systems, it has become clear that many precipitation reactions cannot always be described by the concept of heterogeneous nucleation at some lattice discontinuity followed by diffusional growth. Rather, complex sequences involving prior "preparation" of the matrix are quite common; that is, a transition structure occurs in the parent phase, instead of in some "nucleus" form. Delineation of such subtle sequences appears to be a worthwhile step toward the understanding of solid-state precipitation. Since not many structural progressions of comparable nature have been reported, the objectives of the present survey are to identify and elucidate the various

Jan 1, 1967

By J. van Lookeren

In the case of a reservoir where the oil underlies a large gas cap and overlies bottom water, production can be inzproved considerably if wells are perforated below the water-oil contact rather than opposite the oil-bearing section. The theoretical arguments for this improvement, which in some cases may be tenfold, are supported by experimental evidence. INTRODUCTION Reservoirs frequently consist of one sand body containing an oil layer underlying a thick, gas-bearing section and overlying bottom water (Fig. 1). Wells in such reservoirs are customarily opened up opposite the oil-bearing interval or, rather, opposite the lower part of this interval (Fig. 2). More often than not, it is inefficient or prohibited to blow off large quantities of gas with the oil. This im-psses a severe limitation on the drawdown, which results in low oil-production rates. Because of the small difference in specific gravity between oil and water, the latter will easily cone upwards, so that the production of water together with the oil is not prevented by this completion method. In such a situation wells should be opened deeper, in the originally water-bearing zone. The gas can be shut off by not perforating over the upper part of the interval (Fig. 3) or by a tubing hung close to the bottom of the interval (Fig. 4). Initially much water will be produced, but when steady-state conditions have been established (as depicted in Figs. 3 and 4) larger drawdowns are permissible than in a conventionally completed well, and correspondingly higher oil-production rates will result. Water cuts are only slightly higher because of the small effect of gravity on the water-oil flow distribution. CALCULATIONS The ratio of improvement has been estimated by means of approximate calculations. The completion depicted in Fig. 4 is the most convenient basis for these calculations. By postulating that vertical flow gradients can be disregarded, the Appendix shows that the well-known Dupuit formula can be obtained except for some complication due to the presence of two fluids rather than one. The Appendix makes the reasonable assumption that, for suitable boundary conditions, the oil layer occupies a constant fraction of the total fluid height throughout the reservoir. The oil- and water-production rates can thus be related to the liquid levels in the borehole as follows:

Jan 1, 1966