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By Y. C. Liu, R. H. Richman

The effects of gel,manium and tin on the deformation and 9-e-crystallization textures of copper have been explored in detail with in the copper-rich terminal solid solutions. Addition of solute to copper produces a change in deformation texture from the copper type to the 70 :30 brass type. This transition has been measured quantitatively The types mid proportions of recrystal-lization components have been determined as a function of com-position, and correlation of recrystallization components with specific deformation components is discussed. On the basis of information available in the literature, it has been suggested that the effect of solute elements on the recrystallization texture of copper

Jan 1, 1961

A cooperative service for engineers and their employers under the direction of the American Institute of Mining and Metallurgical Engineers; American Society of Civil Engineers; American Society of Mechanical Engineers; and American Institute of Electrical Engineers, and with the cooperation in Chicago of the Western Society of Engineers, and in San Francisco of the California Section of the American Chemical Society and the Engineers Club of San Francisco. For information as to men available or positions open, address the nearest office.

Jan 1, 1923

By G. W. Imholz

The effect of new discoveries and development of other pools recently discovered is reflected in the increase in production from 586,000 bbl. during 1940 to 758,000 bbl. during 1941 in Coleman County. The States Oil Company's No. I Hudson, Coleman County, was the discovery well of the Silver field, with a total depth of 3540 ft.; initial production, 10,000,000 cu. ft. of dry gas and 60 bbl. of oil per day from the Gray sand, topped at 3482 ft. The first well drilled in the new Jim Ned field was the Merry Bros. and Perini No. I Greer, also in Coleman County. It had a total depth of 3937 ft. and an initial production of 152 bbl. of 42" gravity oil in 6 hr., through I-in. choke, from Gray sand encountered from 3909 to 3937 feet. J. E. Farrell's No. I Rose, Haskell County, was a new discovery, around which no additional wells have been drilled. Total depth was 3002 ft., plugged back to 2780 ft. to test an oil sand encountered from 2663 to 2685 ft., which when perforated with 76 shots at that depth was good for 85 bbl. of 40" gravity oil. In Fisher County, General Crude drilled its No. 12 Flanagan to a total depth of 6746 ft. After plugging back to 4578 ft. to test a sand encountered from 4515 to 4528 ft. it was abandoned as a dry hole. The top of the Ellenburger was reported as 6094 feet. Interest in Jones County continued unabated, largely through the development of the Wimberly pool in the southern part of the county, where five Cisco sands are producing. At present the pool has been defined on the south and the southwest. The structure has 170 ft. of closure; the lower limestone pays producing on top of the structure and the fist pay encountered, the Akard sand, producing on the flanks of the structure. Five deep wells were drilled in Stonewall County (H. and T.C. survey)—the Shell Oil Company's No. I-A Patterson, in block D, with a total depth of 6827 ft., dry and abandoned; the Shell Oil Company's No. I Rutherford, block I, with a total depth of 6239 ft., dry and abandoned; the Leader Oil Company's No. I Bilberry, block D, with a total depth of 5700 ft., dry and abandoned; Forest Development Company's No. 2 Boyd, block D, with a total depth of 4753 ft., dry and abandoned; and the Hunter et al. No. I Boyd, block D, total depth 4757 ft., dry and abandoned. J. E. Farrell drilled his No. I Tipton south of a well that produced from a Strawn sand for some time, to a total depth of 5202 ft., where it was abandoned. The well is in the southwest corner of sec. 43, block 19, T. and P. survey, Nolan County.

Jan 1, 1942

By G. W. Imholz

The effect of new discoveries and development of other pools recently discovered is reflected in the increase in production from 586,000 bbl. during 1940 to 758,000 bbl. during 1941 in Coleman County. The States Oil Company's No. I Hudson, Coleman County, was the discovery well of the Silver field, with a total depth of 3540 ft.; initial production, 10,000,000 cu. ft. of dry gas and 60 bbl. of oil per day from the Gray sand, topped at 3482 ft. The first well drilled in the new Jim Ned field was the Merry Bros. and Perini No. I Greer, also in Coleman County. It had a total depth of 3937 ft. and an initial production of 152 bbl. of 42" gravity oil in 6 hr., through I-in. choke, from Gray sand encountered from 3909 to 3937 feet. J. E. Farrell's No. I Rose, Haskell County, was a new discovery, around which no additional wells have been drilled. Total depth was 3002 ft., plugged back to 2780 ft. to test an oil sand encountered from 2663 to 2685 ft., which when perforated with 76 shots at that depth was good for 85 bbl. of 40" gravity oil. In Fisher County, General Crude drilled its No. 12 Flanagan to a total depth of 6746 ft. After plugging back to 4578 ft. to test a sand encountered from 4515 to 4528 ft. it was abandoned as a dry hole. The top of the Ellenburger was reported as 6094 feet. Interest in Jones County continued unabated, largely through the development of the Wimberly pool in the southern part of the county, where five Cisco sands are producing. At present the pool has been defined on the south and the southwest. The structure has 170 ft. of closure; the lower limestone pays producing on top of the structure and the fist pay encountered, the Akard sand, producing on the flanks of the structure. Five deep wells were drilled in Stonewall County (H. and T.C. survey)—the Shell Oil Company's No. I-A Patterson, in block D, with a total depth of 6827 ft., dry and abandoned; the Shell Oil Company's No. I Rutherford, block I, with a total depth of 6239 ft., dry and abandoned; the Leader Oil Company's No. I Bilberry, block D, with a total depth of 5700 ft., dry and abandoned; Forest Development Company's No. 2 Boyd, block D, with a total depth of 4753 ft., dry and abandoned; and the Hunter et al. No. I Boyd, block D, total depth 4757 ft., dry and abandoned. J. E. Farrell drilled his No. I Tipton south of a well that produced from a Strawn sand for some time, to a total depth of 5202 ft., where it was abandoned. The well is in the southwest corner of sec. 43, block 19, T. and P. survey, Nolan County.

Jan 1, 1942

By S. J. Salat, E. E. Burton

The new Inspiration copper smelter, which introduced unique technological innovations to the copper industry, required a plant material handling system to match. The system has been designed to convey such diverse bulk materials as copper concentrates, copper precipitates, lime, limestone, silica, flue dust, and revert materials. The moisture content in the materials varies from bone dry to a maximum of 25%. Since the summer of I974 when the smelter went into operation, the material handling system ha provided satisfactory and dependable services.

Jan 1, 1981

By Charles H. Fulton

CHARLES H. FULTON, chairman, presided at the first session of the Mineral Industry Education Division on Wednesday morning. Reporting for the program committee, Edward Steidle, its chairman, pointed out that its function was not to arrange programs for meetings but to plan a program for the Division to follow in the development of its activities. This was appropriately followed by presentation and discussion of his paper, "Basic Trends in Mineral Industries Education," which, being available in printed form, was only presented in oral abstract. Jay A. Carpenter submitted interesting written discussion that was read, in his absence, by A. M. Smith. Most of the morning was devoted to the discussion of the paper, which was too extensive and ranged too widely to attempt to report in much detail. H. T. Mann, H. P. Hammond, Cadwallader Evans, C. H. Fulton, T. T. Read, D. F. McFarland and P. B. Bucky joined in the discussion, Mr. Hammond making a plea for more unification in mineral industry education, saying that in the study he made for the Society for Promotion of Engineering Education about 35 different curricula preparatory to work in the mineral industry were discovered to exist. He felt that most of the needs of the mining industry could he met by men who had had four years of engineering training of good enough basic quality to permit them to advance along special lines. However, there was apparently a growing demand, as reflected by the increasing number of candidates for the Master's degree in engineering, for men with more thorough training in the fundamentals.

Jan 1, 1933

MAJOR AWARDS JAMES DOUGLAS GOLD MEDAL 1960-Augustus B Kinzel "For outstanding contributions and inspiring leadership in the field of electrolytic and electrothermic winning of nonferrous metals and for his notable administrative ability " BENJAMIN F FAIRLESS AWARD 1960-Charles McElroy White "His ability, energy and determination in starting the top-pressure blast furnace and foresight in providing it with prepared burdens have created the world's dominant metal producer " HAL WILLIAMS HARDINGE AWARD 1960-Samuel H Dolbear "Eminent mineral consultant and engineer-first chairman, Industrial Minerals Division of AIME-first editor, 'Industrial Minerals and Rocks'-for the improvement and increase of industrial mineral knowledge "

Jan 1, 1960

EVERY forward-looking mining company realizes the need for employing graduate mining engineers so that there will be a supply of qualified men from which to draw for company officers, executives, and mine managers. The mining industry is competing today with numerous other fields of engineering for its supply of technical men, many of which are more attractive than mining because of better pay, living conditions, and well- regulated company training programs. The Ontario Mining Association and the mining companies of Ontario are conducting a postgraduate training plan which if adopted in the United States, might well encourage top quality men to study mining.

Jan 3, 1950

By R. Michael Craig

Mr. Juvkam-Wold's article is a timely and much needed presentation of the method of depressurization to reduce ground- water inflow into mine shafts. The article is very informative and discusses the effects of depressurization upon shaft inflows adequately. However, the article omits a discussion of another important benefit of depressurization: the reduction of potential for artesian burst or, as it is also called, floor heave. Confined aquifer systems (artesian aquifers) can contain water under several hundred pounds per square inch (psi) of pressure. For example, water levels at elevations of 455 m (1500 ft) or more above the top of the Westwater Canyon member of

Jan 1, 1984

Percussion drilling with tungsten carbide insert button bits ranks among the most significant advances in both underground and surface drilling in medium and hard rock formations. Getting top performance and life from these upfront components is not particularly difficult if one pays attention to the basics in operation and maintenance. For some reason, a few of the essential operating and maintenance steps for getting the most from these tools seem to have gotten turned around; instead of operating at the near optimum levels, some miners, in following myths or misunderstandings about them, are shortchanging their optimal utilization. Let's examine the two most harmful ones.

Jan 8, 1978

There were two official representatives of Foreign Governments as guests at the Chicago Meeting. One was Frederick Goransson, managing director of the Saudvikens Steel Works, who represented the Jernkonteret, the Iron and Steel In-stitute of Sweden, and who came to this country especially for our meeting. The other distinguished guest was Commander Toublet, who repre-sented the French Embassy. Commander Toublet delivered a most polished address at the Banquet, dealing with the felicitous relations existing between this country and France for the last 150 years. Com-mander Toublet was accompanied by Mrs. Toublet, who won the hearts of all the ladies present, whose guest she was.

Jan 11, 1919

United Engineering Trustees, Inc James L Head, '55, E C Meagher, '56, Gail F Moul¬ton, '57 Advisory Committee to Real Estate Committee Cleveland Dodge, Herbert Hoover, Paul D Merica The Engineering Foundation W M Peirce, '56, A M Gaudin, '58 Research Procedure Committee A M Gaudin, March '54 Engineering Societies Library Board Frank T Sisco, '54, E M Wise, '56, James L Head, ex officio Engineering Societies Personnel Service Board of Directors E J Kennedy, Jr, E H Robie

Jan 1, 1954

By John Henry Harden

WITH imperfect instruments it is impossible to make accurate surveys; the results are inaccurate maps, with their attendant consequences. The design of the writer is to describe an improved form of tripod head, and certain defects in an English transit and a miners' dial, with the method taken to remedy the defects of the transit. When the present transit superseded the surveyor's compass, there was one special objection brought against it, and with some show of reason ; namely, that the tripod of the compass with its ball and socket motion, allowed a quicker levelling-up (and, consequently, more work) than was possible with the transit. To this objection it was replied, that the ball and socket would not allow the instrument to be levelled with the same degree of precision that could be attained with the levelling screws, and that if time was sacrificed greater accuracy was attained. Nevertheless, it is a well-known fact that in this country, and especially in England, the compass or miners' dial holds its ground solely from its rapid adjustment. Ever since the introduction of the transit, efforts have been made to give to this instrument the same facility of levelling possessed by the compass or dial, and the same means have been tried, i. e., a . ball and socket motion, since a modification of this in some form was the only method that would answer. The upper part of a transit is, however, much heavier than the corresponding parts of a compass, and, therefore, requires more binding power, which cannot be ob¬tained with an ordinary ball and socket joint. It has been a study with instrument-makers to combine the facility of these two tripods -the quickness of the ball and socket with the steadiness and accuracy of the screws; but in all attempts in this direction the ball and socket of the compass has been literally followed, the entire stability of the instrument depending upon the friction of the ball in its socket. There is great need for a tripod that can be more easily manipulated than the present form, for it rarely happens that an engineer has a level surface on which to set his instrument, and very often

Jan 1, 1879

THERE can be little doubt in the mind of anyone of the great interest which has been provoked in the mining and petroleum industry by the com-paratively new geophysical methods of prospecting, after the sessions at this year's meeting of the Institute. Not only were the sessions very well attended but every¬one seemed most attentive. Although the discussion was somewhat limited in general, that may well be at-tributed to the newness of the subject. Two sessions on this subject were planned originally, but these gave insufficient time for the presentation of all the papers prepared and a third session was abso-lutely necessary. The first meeting dealt entirely with the gravity methods and was completed in the scheduled time owing to the fact that but two of the five papers listed were read. The second session was devoted to magnetic and electrical methods, the completion of which had to be carried over into the third period of geophysics. The first session on geophysical prospecting, and in-cidentally the first scheduled Institute meeting devoted entirely to this subject, was most appropriately opened by E. L. DeGolyer, the chairman of the session. It was through the efforts of Mr. DeGolyer that the first gravity work, as applied to prospecting, was under-taken in this country. Again most appropriately, the first paper presented was given by Donald C. Barton, who carried on the first work with the Eötvös torsion balance in America and aided materially in its development. A subject, the theory of which is so difficult to understand as it is generally presented, was so clearly illustrated and ex-plained by the speaker that even a novice could grasp the fundamentals. Dr. Barton, in showing actual re-sults obtained in torsion balance surveys with the in-terpretation of the sane and later drilling records, was free in stating that there are many limitations to the field in which this and the other geophysical instruments may be successfully employed. This paper called for considerable discussion relative to the application of the torsion balance to gravity surveys over various types of structures. During the course of this discus-sion a very important point was emphasized by the chairman, namely, that for successful application of any or all of the scientific methods of prospecting, a back-ground of experience is absolutely necessary to serve as a basis for further work. This can only be secured by contributions from the results of actual prospecting work.

Jan 3, 1928

By William Sellers

tested without knowing anything of their chemical composition. I had these pieces separately placed upon 10-inch bearings under a 7-gross ton lianlrner, a piece of 2½-inch round iron laid upon them as a fuller, and the hammer allotved to fall from 20 inches above the fuller, which, according to Haswell, gave a ldow of 67.75 gross tons. The pieces were then turned orcr, the fuller placed upon the convex surface, and the harnnler allowed to fall from 13 inches above the fuller, giving a blow of 58.46 gross tons. You will see that the rails do aot show ally bigrls of ruptnre, and their color at the points of torture prove them to have been absolutely cold when the test was made. I thirk these rails ought to be reasonably safe in the track. As you see by this piece of the head of one of these rails, I had it plarred, and then some teeth cut in it by a cold clrisel, and one-half of them pounded down with a hammer. The teeth of my rack did not break off. The analyses of these rails substquently made are: I. 11. Carbon,... 0.110 0.880 Silicon,..0.050 0.058 Phosphorus ,..0.086 0.082 Manganese,.. 0.042 0 840 In conclusion, I will say that Dr. Dudley's paper as a contribu tion to our knowledge of steel rails is valuable and interesting, but I protest against his conclusions king reoeived as manufacturing or comtnercial axioms. From its being presented in the form-of a report to the leading railroad of the country from one of its trusted officers, as well as from the tone of the concluding deductions, it is liable to be so received by railroad men. If any railroad com pany desires rails made under either of Dr. Dudley's formulas, and are willing to pay a price large enough to cover the loss in making them, dl and good; but so long as the rail makers are compelled to gwrrantee the wear of their rails for a given number of years, justice reqnires that. the composition of the steel from which these rails are made should be left to them. WILLIAM SELLERS, PHILADELPHIA: The very interesting paper upon the wear of steel rails that has just been read preseak the record of a series of investigations that are extreniely valuable, and the deduction that bas been drawn from the results noted seems to be unavoidable; the tests, however, to which it is proposed steel rails shall be subjected hereafter, with a view to determine their quality, sllould

Jan 1, 1881

By Garth M. Crosby

Hugh E. McKinstry (Professor of Geology, Laboratory of Mining Geology, Harvard University, Cambridge, Mass.) Pre-Cambrian age for the Coeur d'Alene mineralization, as indicated by isotope studies and recently discussed by Silverman, Long, and Kulp' would explain some features of the mineralogy of the district that have long been a puzzle. In the Silver Belt, especially in the Sunshine mine, lead-zinc min erali zation passes downward into tetrahedrite ore. Although commercially speaking this is a rich silver zone, the silver is, quantitatively, a mere impurity amounting to a small fraction of 1 pct. In effect the zonal change is from lead-zinc down into copper mineralization—-the usual zonal change that occurs in many districts. In the Burke-Mullan portion of the district, on the other hand, lead-zinc ore does not pass downward into copper mineralization of the Sunshine type. Instead, pyrrhotite appears in depth while the tenor in lead and zinc declines. The change occurs at increasingly greater depth away from the Gem stocks, deepening irregularly by some 3000 ft within two to four miles. As noted by Crosby, biotite, grunerite, and garnet appear in the deep zone. The marked difference between this apparent zonal change and the more nomal change to a copper zone is quite explainable if already existing pre-Cambrian veins have been locally metamorphosed by a Tertiary intrusive. The chief obstacle to this explanation is the evidence that mineralization cuts Laramide intrusives, but evidence on this point is conflicting as indicated by Crosby's observations and summary. This is not the first instance of a problem in determining the time-relationship of mineralization to a spatially associated intrusive. At the Noranda mine veins of chalcopyrite extend into a diabase dike which apparently cuts the ore, although Price2 concludes that the ore is later. However, at the Normetal mine diabase of a similar dike is thought3 to intrude the orebody but is cut by stringers of chalcopyrite. In the Sullivan Mine, B. C.,4 galena follows a fracture in a larnprophyre dike which, itself, cuts the main orebody. In the Sudbury district dikes of olivine diabase are clearly younger than the nickel ore, yet where they cut the Creighton orebody they contain stringers of chalcopyrite. In the laboratory, Hawley5 has developed veinlets of sulfide (chalcopyrite) it] silicate gangue by heating specimens of ore in a stream of H2S at 410 °C. From this and other evidernce. it seems clear that sulfides can be transferred from one site to another — at least through short distances — at temperatures well below their melting points. It would seem then that even if sulfide Mineralization in the Gem stocks can be shown unequ ivocably to be later than the intrusive the possibility of "remobiliza tion" need not be more than local. Thus the zonal relationships are quite in accord with a pre-Cambrian age for original deposition of the lead, zinc, copper, silver, and uranium in the Coeur d'Alene district. REFERENCES 1. A. Silverman, A. Long, and J. L. Kulp: Discussion of: The Gem Stocks and Adjacent Orebodies, Coeur d'Alene District, Idaho. Mining Engineering, May 1960, pp. 470-471; AME Trans., 1960, vol. 217, p. 117. 2. Peter Price: Geol. & O. D. at the Home Mine, Noranda, Quebec. Can. Inst. M & M Bull 263, 1934, p. 108; also,Trans. CIMM 1939, pp. 108-140. 3. w. L. Brown Nometal Mine in structural Geology of Canadian Ore Deposits, Montreal, 1948, p. 690. 4. C. O. Swanson and H. C. Gunning: Geology of the Sullivan Mine. Can. Inst. Mining & Met. Trans. vol. 48, 1945, p. 653. 5. J. E. Hawley: Heat Effects on Sulphides and Possible Applications. Univ. Toronto Studies, Geol. Ser. No. 46, 1941, p. 34.

Jan 1, 1961

SMALL things are customarily moulded in two ways (unless they have undercut parts which hold them in the moulds); that is in clay, or with natural or which artificial earthern powder made in halves in either wooden boxes or bronze frames. This also depends on whether the object is larger or smaller. Now if you wish to mould with moist clay, you must grease your relief with oil or pig fat; apply a dusting of charcoal, ashes, or cuttlebone on it; or gild or silver it dry with gold, silver, or tin foil. Then, first make with moist and somewhat firm clay a plate as, thick and large as can conveniently hold your relief, and carefully set the latter halfway into this and let it dry. Then, greasing or dusting it again, make the other half. When both are well dried, take out your relief and at the top make its gates and vents. If plastering is needed, do it. Finally, bake the halves, fit them together, and tie them well, as you wish, using the procedure that I taught you in the discussion of brass. But if one has to make a large quantity of works of one kind, he should for the sake of convenience use the method with powder [120] because it is short and requires less time and expense. Therefore if you wish to do this, you need to have several pairs of bronze frames or wooden boxes, higher than half the relief that you wish to mould, and of convenient length. On a flat board always keep half of one of these frames full of powder that has been slightly moistened for moulding, as I told you, so that by pressing with the ends of the fingers and with the hand it holds together as well as possible. Level it off with a cutting tool and when leveled put a flat board over it and turn it over. Turn it on to a dusting of ashes so that it will not stick, dust it on the other side, and remove the excess by blowing it off Then mould the thing that you wish to mould, pressing it halfway in once or twice, always taking it out and putting it back again. Then the other frame is fitted in its place and filled with earth by pressing and squeezing it carefully. Then it is leveled off on the outside with a sharp tool as you did with the other part, and then one of the parts of the frames is lifted up with the point of a knife or some other tool and,

Jan 1, 1942

By M. Prats

This paper presents a method for obtaining the correct values of the breakthrough sweep efficiency of the staggered line drive, taking into account the proper shape of the breakthrough streamline. Results obtained were different from those previously published, which were obtained by using an inexact shape of the breakrhrough streamline. INTRODUCTION In Section 9.31 of Muskat's' The Flow of Hotnogeticous Fluids Through Porous Media, it is stated that in a staggered line drive flood "the streamline of highest average velocity [is] the line of centers between input and output wells" (see Fig. I). Muskat used this concept to determine the relationship between the breakthrough sweep efficiency and the geometry of the staggered line drive pattern. Although it is clear from symmetry considerations that the breakthrough streamline passes through the midpoint between input and output wells, it is equally clear, as shown in Fig. 239 of Ref. 1, that the breakthrough streamline is not represented very well by the straight line joining the input and output wells. Therefore, it is desirable to determine the proper relationship between the breakthrough sweep efficiency and the pattern geometry by using the proper shape of the breakthrough streamline. METHOD OF SOLUTION It was found that the effect of the geometry of the staggered line drive on the breakthrough sweep efficiency can be investigated easily by making use of the method developed in Ref. 2. With this method, it can be shown that the general complex potential for the staggered line drive, which can be considered as a rectangular five-spot, is given in the coordinate system of Fig. 1, by O(z) = In cn(z\m) = +(x,y) + i $(x, y) . (1) where z = x + iy, +(x, y) is the potential distribution and $(x, y) is the stream function. The function cn (zm) is a Jacobian elliptic function of parameter m and has simple zeros at z,. = (2n + 1) K + 21iK and simple poles at z, = 2nK + (21 + 1)iK. Thus, the complex potential behaves like a(z) = ln(z - zr.) in the neighborhood of the production wells and behaves like a(z) = - ln(z - Z,) in the neighborhood of the injection wells. Since (z - z1.v) = rll.ei, we note that the potential + has the proper logarithmic behavior near the two wells, while the stream function $ varies with the angle, decreasing clockwise around the production well and increasing clockwise around the injection well. The functions K(m) and K'(tn), related by K(m) = K'(m,), where m + m, = 1, are known as the complete elliptic integrals of the first kind. By use of other properties of the Jacobian elliptic functions, the general stream function distribution for the staggered line drive can be obtained from Eq. 1: From the Jacobian elliptic function values, sn(0lm) = 0 dn(O(m) = cn(0jm) = 1, and f[K'(m)Iml = 03, it follows that the stream function given by Eq. 2 satisfies the proper symmetry conditions near a production well P located at [K(m), 01 and an injection well I located at [0, K' (m)]. That is, the line IOP in Fig. 1 is a streamline with value G (0. 0) = -0. and the straight lines connecting I and P to the point [K(m), K' (m)] is a streamline of value $[K(m), K' (m)] = -7/2. Similar symmetry conditions are obtained near other wells. It should be nuled that for m = m1, = 0.5, Eq. 2 reduces to the stream function distribution of the regular five-spot given in Ref. 7. SHAPE OF THE BREAKTHROUGH STREAMLINE It is apparent, from symmetry considerations, that the breakthrough streamline ($,) passes through the point [K(m)/2, K' (m)/2]. Its value there is so that the shape of the breakthrough streamline $,, is given by

Jan 1, 1957

By P. R. Sahm, T. V. Pruss, D. A. Gandolfo

Cb 3 Sn powders were hot-pressed to estahlish densi-fication conditions and assess the possible use of such compacts in multiphase structures with ceramic or magnetic inclusions. Superconducting transition temperatures, Tc, were measured as a function of powder particle size, pressing temperature, and second-phase admixtures. The highest transition temperatures were found in coarse powder (5 to 500 u) compacts and were only weakly depended on pressing temperatures up to 1200°C. Fine powders (below 5 p), however, both single-phase CbsSn and Cb3 Sn-composites, showed a stronger dependence on hot-pressing temperatures. While Al2 O3 phase admixtures did not affect T, much more, a Pronounced T, degradation was observed upon the addition of ferrimagnetic Fe2 Mno. 5 Zno.5 O4 powders. Likewise, critical current densities, Jc, at 4.2° K were lowered appreciably in the ferrite doped samples, whereas the neutral A1203 inclusiow gave slightly improved Jc values. MULTIPHASE structures in electronically active materials have recently gained in interest as pointed out by Galasso in a review article.' In superconductors the most widely reported group are eutectic alloys which have been mostly investigated with respect to the proximity effect.2"4 In addition, "artificial eu-tectics", for example in the form of mercury-vycor glass sponge5 or fine niobium wires imbedded in a copper matrix,= have been prepared to attain higher critical fields and critical current densities. The idea was to enhance flux pinning phenomena by second-phase inclusions or ho1es. 7 Flux pinning should also be possible by the introduction of insulator inclusions into a superconducting matrix. Ceramic-metal combinations are most easily produced by hot pressing (= pressure sintering), as it permits an almost unlimited selection of material combinations. Cb 3 Sn has been prepared by vapor phase growths or in the form of thin films. Large compacts must be sintered,1° however, and normally present difficulties. At temperatures below 1350°C insufficient densities are obtained and at higher temperatures the loss of tin due to dissociation upsets the stoichiometry. Hot pressing is a natural approach to circumvent the problems, since one can obtain satisfactory densities despite low sintering temperatures. This work was mostly concerned with establishing conditions to hot press Cb3 Sn and Cb3 Sn multiphase structures (= composites), because no data are presently available, and to evaluate these with respect to their transition temperatures. However, a few measurements on critical current densities were also carried out, in particular to assess the value of ferrimagnetic inclusions. I) EXPERIMENTAL PROCEDURE The experimental procedure involved the preparation of feed material and powders, hot pressing, and evaluation of the resulting ingots. As no attempts were made to synthesize Cb3Sn from the elements during hot pressing, feed material had to be produced. For this purpose, a stoichiometric Cb-Sn powder mixture was compacted into a 3-cm-diam ingot (80,000 psi) and then inserted into a quartz tube and evacuated. Rf heating was employed. Above the tin melting point (230°C) liquid tin was forced out of the ingot, but was pulled back by capillary action after approximately 0.5 hr of continuous pumping at 700°C. Thus, it appears that evacuation at this temperature caused desorption of impurity gas creating wetting surfaces which, later on, favored alloying at relatively low temperatures. After a presintering period of 17 hr at 800°C, the quartz tube was tipped off and sealed into another such larger-diameter tube which, in turn, was connected to a pump system. This configuration permitted a temperature treatment at 1400°C, carried out for 65 hr, without collapsing of the glass walls or unfavorable chemical interaction of Cb3Sn with the quartz. The resulting material was

Jan 1, 1969

By J. B. Cohen

EARLY investigators1-4 reported that additions of beryllium to silver caused embrittlement. The in-termetallic phases which are now known to exist5,' were not known at the time. Solidification appeared to occur by a simple eutectic reation.4,7 (The primary beryllium-rich phase appeared globular, when the liquidus temperature was near the melting point of pure beryllium, and angular when the liquidus was much lower; in discussion of Sloman's work,4 it was suggested that this difference was due to an intermetallic compound which was not revealed by the polishing technique.) In the investigation reported here, it was found that if the compounds now known to exist were avoided, certain beryllium-silver alloys containing large amounts of the primary beryllium phase possessed sufficient ductility to be cold formed. Alloys containing 14 and 20 at. pct Ag were prepared from vacuum-cast beryllium containing 1.0 to 1.2 pct impurities and silver, 99.99+ pct pure. The elements were melted together by induction in beryllia or alumina crucibles under argon at less than 1 atm pressure. The cooling rate was adjusted by regulating the temperature of the melt and by reducing the power to zero without stopping the water flow in the induction coils, which were in contact with the crucible. Ingots were about 0.75 in. in diam with a grain size of 0.12 to 0.25 in. Microscopic investigation of transverse or longitudinal sections of an ingot cast from a temperature well above its melting point showed that, in general, the compounds did not form, presumably because of rapid cooling; the alloys consisted of beryllium-rich particles in a silver-rich matrix as shown in Fig. 1. A eutectic structure was not observed, probably .due to the low beryllium concentration of the eutectic composition and eutectic divorcement. Within a given grain, the small globules of the primary phase were all oriented in the same direction, as indicated by examination under polarized light; the orientation varied from grain to grain. This suggested that the globules were branches of the same dendrites. If cooling was too slow, a third constituent was observed in the microstructure; because it formed around the primary beryllium-rich globules it was Fig. 1—Ag-Be alloy, 18.6 at. pct Ag, as-cast. Bright field illumination. Etched with an aqueous solution of NH,OH and H2O2. X500. Reduced approximately 21 pct for reproduction. probably the 6 compound. A thin ring around an ingot often contained this constituent. When this compound was present in large quantities, or the silver segregated so that large regions occurred with the beryllium-rich globules in contact, sections from the ingot were brittle. When the compound was initially absent, it was possible to carry out reductions in thickness of 50 pct by cold rolling with only limited edge cracking; failure did not occur until reductions of 80 pct. A typical cross section after cold rolling is shown in Fig. 2. After simple bend tests, microcracks were found; these apparently were difficult to propagate in the two-phase structure, as the specimens continued to behave in a ductile manner after the cracks appeared. Similar cracks would probably be closed during rolling. It is apparent in Fig. 2 however, that the primary beryllium particles undergo extensive plastic deformation. Hardness values of the alloys indicated that some work-hardening occurred during cold working. Fig. 2—Ag-Be alloy, 18.6 at. pct Ag, reduced 83 pct in thickness by cold rolling. Bright field illumination. Etched with an aqueous solution of NH,OH and H2O2. X500. Reduced approximately 21 pct for reproduction.

Jan 1, 1961