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By C. Ernest Birchenall

TWO recent papers1,2 cite measurements of surface contour changes on copper which, when attributed to surface self-diffusion, can be interpreted to yield activation energies for surface self-diffusion that approach1 or exceed2 those reported for volume self-diffusion in the same metal.3 It is acknowledged2 that AS must be assigned much too large a value to be physically reasonable in order to make the theoretical Do's agree with the experimental values, if the jump distance is of the order of the interatomic distance. However, long jumps would probably lead to marked anisotropy on planes that consist of ridges and valleys (like (110) in fcc) whereas only mild

Jan 1, 1963

By D. B. Hunter, H. W. Rosenberg

The titanium-rich portion of the Ti-Pd system was investigated from 0 to 75 wt pct Pd by metallo-graphic and X-ray techniques. A 0 eutectoid occurs at 24 wt pct Pd and 1190°F. Two compoutzds are indicated in the region below 75 wt pct Pd, Ti,Pd and Ti2Pd3. The solubility of palladium its a titanium is low, probably less than 1 pct. In 1960 Rudnitskii and Birunl published a complete version of the Ti-Pd phase diagram. However, their work was in disagreement with the earlier literature in that they reported only one inter metallic compound, whereas three had been reported earlier. In view of these discrepancies, it was therefore necessary to redetermine those portions of the diagram of immediate interest. The following account describes our work on the system over the range of 0 to 75 wt pct Pd. MATERIALS AND METHODS Distilled titanium sponge and elemental palladium were used in the formulation of the alloys; the chemistry of these materials is detailed in Table I. The alloys were prepared as 10 to 50 g blended compacts that were melted into buttons by arc melting under gettered argon on a water-cooled copper hearth. Weighing of the ingredients before and after melting showed that negligible weight changes occurred. Therefore, no analyses were undertaken and the compositions of all alloys are nominal. All alloys were fabricated by hot rolling at 1700°F to 0.070-in.-thick sheet. Scale was removed by sandblasting and pickling in a 5 pct HF-35 pct HNO,, balance H20 solution. For metallographic examination, specimens were mounted after heat treatment transverse to the rolling direction, ground on silicon carbide papers of increasing fineness to 600 grit, and then electro-polished using a solution containing 600 ml me-thanol, 60 ml perchloric acid, 360 ml butyl cello-solve, and 2 ml "Solvent X". Unless otherwise specified, etching of alloys containing up to 42 pct Pd was carried out by swabbing with a 12 pct HN03-1 pct HF aqueous etch where a bright etch was required, or by a 1 pct hydrofluoric in saturated oxalic acid solution where contrast between phases was required. The Ti-52.8 Pd alloy was etched with a solution of 25 ml HF, 40 ml glycerine, 35 ml methanol, and 18 g benzalkonium chloride. For X-ray examination, 1/2-in.-square speci- mens of sheet were mounted flat in a standard 1-in. metallographic mount and ground and polished as above. X-ray diffraction was performed using a Norelco type 12045 Diffractometer, employing CuKa radiation with a nickel filter at 40 kv and 20 ma. Specimens were rotated about the sheet normal during exposure. Although this procedure did not remove the effects of sheet texture from the relative intensities, it had the advantage that oxidation or contaminants entering during preparation of powder samples could not confuse the patterns obtained. RESULTS AND DISCUSSION Fig. 1 illustrates the Ti-Pd phase diagram according to Rudnitskii and Birunl with the work of the present authors superimposed. Both interpretations agree that the system is of the 0 -eutectoid type with an extensive 0-phase field, and that the eutectoid temperature is just below 1200°F. There is also agreement that the solubility of palladium in a titanium is restricted. Our work would indicate that the a solubility of palladium is low, probably less than 1 pct. However, whereas Rudnitskii and Birunl place the eutectoid composition at 41 wt pct Pd, this investigation shows it to be at about 24 wt pct Pd. Moreover, this investigation confirms the existence of compounds at Ti2Pd and Ti2Pd3, whereas Rudnitskii and Birun report only a single Berthol-lide phase covering the TiPd to TiPd, range. Laves et a1.' and Wallbaum, whose work was summarized by Maykuth , reported the existence of Ti2Pd3 and TiPd, in addition to Ti2Pd. More recently, Nevitt and Downe~' have reported the structure of

Jan 1, 1965

[Trans. No. Place Date Vol. Page 1. Wilkes-Barre, Pa.*.. *May: '71.. 1 3 2. Bethlehem, Pa Aug. '71.. 1 10 3. Troy, N. I X Nov. '71.. 1 13 4. Philadelphia, Pa Feb. '72.. 1 17 5. New York, N. Y.*.... May, '72.. 1 20 6. Pittsburgh, Pa Oct., '72.. 1 . 25 7. Boston, Mass Feb., '73 1 28 8. Philadelphia, Pa.*.... May, '73 2 3 9. Easton, Pa Oct., '73 2 7 10. New York, N. Y Feb., '74.. 2 11] [ ]

Jan 1, 1925

By H. O. McLeod, J. M. Campbell

This paper presents the results of the data obtained in the first stage of a long-range study at high pressures of the system, vapor-hydrate-water rich liquid-hydrocarbon rich liquid. The data presented are for the three-phase systems in which no hydrocarbon liquid exists. Tests were performed on 10 gases at pressures from 1,000 to 10,000 psia. One of these was substantially pure methane, and the remainder were binary mixtures of methane with ethane, propane, iso-butane and normal butane. Several conclusions may be drawn from the data. 1. Contrary to previous extrapolations, the hydrocarbon mixtures tested form straight lines in the range of 6,000 to 10,000 psia which are parallel to the curves for pure methane, when the log of pressure is plotted vs hydrate formation temperature. 2. The hydrate formation temperature may be predicted accurately at pressures from 6,000 to 10,000 psia by using a modified form of the Clapeyron equation. The total hydrate curve may be predicted by using the vapor-solid equilibrium constants of Carson and Katz' to 4,000 psia and joining the two segments with a smooth continuous curve between 4,000 and 6,000 psia. 3. The use of gas specific gravity as a parameter in hydrate correlations is unsatisfactory at elevated pressures. 4. The hydrate crystal lattice is pressure sensitive at elevated pressures. INTRODUCTION Prior to 1950 many studies had been made of the hydrate forming conditions for typical natural gases to pressures of 4,000 psia.""'"'"" Most of these attempted to correlate the log of system pressure vs hydrate formation temperature, with gas specific gravity as a parameter. One of the more promising correlations was made by Katz, et al, which utilized vapor-solid equilibrium constants. The only published data above 4,000 psia are those of Kobayashi and Katz7 for pure methane to a pressure of 11,240 psia. In the intervening years, most published charts for the high-pressure range have represented nothing more than extrapolations of the low-pressure data, with the methane line serving as a general guide. The reliability of these charts has become increasingly doubtful (and critical) in our present technology as we handle more high-pressure systems. The portion of our high-pressure hydrate research program reported here was designed to: (1) investigate the reliability of existing charts; (2) obtain actual data on gas mixtures to 10,000 psia; and (3.) develop a simple hydrate correlation that was more reliable than those which simply used specific gravity as a parameter. Binary mixtures of methane and ethane, propane normal butane, or iso-butane were injected into a high-pressure visual cell containing an excess of distilled water. Hydrates were formed and then melted to observe the decomposition temperature of the hydrates at pressures from 1,000 to 10,000 psia. EQUIPMENT The equipment consisted of a Jerguson 10,000-lb high-pressure visual cell, a 10,000-1b high-pressure blind cell and a Ruska 25,000-1b pressure mercury pump. The visual cell was placed in a constant-temperature water bath controlled by a refrigeration unit and an electric filament heater. A Beckman GC-2 gas chromatograph was used in analyzing the gas mixtures after each run was completed. EXPERIMENTAL PROCEDURE After evacuating the gas system, the heavier hydrocarbon was injected into the high-pressure mixing cell to that pressure necessary to give the desired composition. This cell then was pressured to 1,100 to 1,200 psia by methane from a high-pressure cylinder. The mixing cell holding the gas contained a steel flapper plate and was shaken intermittently over a period of 15 minutes. After mixing, the valve to the high-pressure visual cell containing excess distilled water was opened, and the gas mixture was allowed to flow into the cell. The temperature in the water bath was lowered 10" to 15'F below the estimated hydrate decomposition point. As a first check, the temperature was increased at a rate of 1°F every six minutes to find the approximate point of decomposition. It was again lowered 1.5° to 5°F to form hydrates. The temperature was raised to within l° of the estimated decomposition point and then increased 0.2F every 10 to 15 minutes until the hydrates decomposed. This procedure was repeated at various pressures to obtain 7 to 13 points for each mixture between 1,000 and 10,000 psia. After completion of the hydrate decomposition tests, the gas mixture composition was analyzed with a calibrated gas chromatograph. These gas analyses have an estimated error of ± .1 per cent.

By Louis Huber

THE Liberty tunnels extend through a very steep hill in Pittsburgh (locally called Mount Washington) for a distance of slightly over a mile. The two tunnels parallel each other and are 59 ft. apart, center to center (Fig. 1). They are for vehicular traffic, and in each there is ample space for two lines of vehicles. Northbound traffic, towards downtown Pitts- FIG. 1.-NORTH PORTAL OF LIBERTY TUNNELS. NOTE THE WINDBREAK AT END OF EAST TUNNEL. burgh, is confined to the east tunnel and southbound traffic to the west tunnel. The South Hills residential district is separated from downtown Pittsburgh by Mount Washington, a steeply rising escarpment south of and adjacent to the Monongahela River. The Mount Washington district immediately south of the Monongahela River has been reached, for many

Jan 1, 1927

By Irvin Lavine

THE discovery of several large deposits of natural sodium sulfate (Glauber salt) in the northwestern part of North Dakota during the summer of 1934 might have been anticipated from a knowledge of the topography and geology of this territory and from the presence of natural C A N A D A FIG. 1.-LOCATIONS OF GLAUBER SALT DEPOSITS, NORTHWESTERN NORTH DAKOTA. North Lake (deposit No. 7) is not shown on this map. It is approximately 13 miles north of Miller Lake (deposit No. 3). sodium sulfate deposits in western Canada, which have been known for several years. In the northwestern part of North Dakota is a chain of shallow lakes, which continues northward into Saskatchewan. Over twenty million tons of Glauber salt has been proved present in these North Dakota deposits. (See Fig. 1.)

Jan 1, 1936

AT the meeting of the Board of Directors in March 1945, plans were discussed for a special General Meeting to commemorate, in an appropriate way, the founding of the Institute at Wilkes-Barre, Pennsylvania, in 1871. It was decided that seventy-five years of growth, progress, and achievement; of service to the profession, to the mineral industry in all its branches, and to society at large should be fittingly celebrated. Harvey S. Mudd, then President of the Institute, was authorized to appoint a General Committee on Arrangements as well as necessary working committees. On June 6, 1946, Louis S. Cates, as President, at a special meeting of the Pennsylvania-Anthracite Section at Wilkes-Barre, officially announced plans or a three-day meeting to be held at The Waldorf-Astoria, in New York City, September 16-18, 1946. Four major sessions to be addressed by eminent speakers had been-planned in some detail to constitute a "World Conference on Mineral Resources." The U. S. Department of State had dispatched a 1500-word airgram to all its diplomatic posts giving worldwide publicity to the scope and importance of the meeting; and formal invitations had been issued to more than 150 institutions in 40 foreign countries to send official delegates. These included scientific and engineering societies, educational institutions, and sundry government agencies connected with the mineral industry. However, about a month later it was found necessary to postpone the celebration. The reason was an unforeseen expansion in the requirements of the United Nations for hotel living space in New York to accommodate delegates to the meeting scheduled to start September 3; and, of course, U.N. delegates would be given priority. It was decided to postpone the Celebration-conference to the week beginning March 17, 1947; t6 devote the first three days primarily to the Celebration; and to follow it with the technical sessions, committee meetings, and other functions, that are regular features of the Annual Meeting. To accommodate the combined "show" it would be necessary to hold some of the Annual Meeting sessions at another hotel;

Jan 1, 1947

THE 143d* meeting of the American Institute of Mining and Metallurgical Engineers was held in New York, Feb. 19-22, 1934. It consisted of the annual business meeting, 45 technical sessions at which 217 papers were presented (more than ever before), two sessions of the Board of Directors, two meetings of Section delegates, three formal lectures, luncheon Monday, Tuesday and Wednesday for members and guests, three group dinners and five group luncheons, eight committee meetings, the annual reception and dinner dance, an informal dance, a smoke-dinner and the annual meeting of the Woman's Auxiliary. Attendance showed an improvement over the previous year, as follows: Total, 1534 in 1934, and 1475 in 1933; dinner dance, 543 and 426; smoker-dinner, 425 and 394; informal dance, 295 and 250; women's registration, 160 and 133; luncheons, 1034 and 734. The Coal Division held a general session and three sessions on Coal classification. It also met jointly with the Committee on Ground Movement and Subsidence. At the general session, John B. Dilworth presented a report of the Committtee on Methods of Valuing Coal Proper- ties and R. H. Sweetser a report of the Committee on Evaluation of Coal for Blast-furnace Coke. C. B Huntress, Executive Secretary of the National Coal Association, was the principal speaker at a luncheon on Monday, at which Eli T. Conner, Chairman of the Division, presided H. N. Eavenson, newly elected President of the Institute, and Edward W Parker, Secretary-Treasurer, of the Anthracite Institute, also spoke. The Executive Committee of the Division met Tuesday afternoon. The Sectional Committee on Classification of Coal met on Thursday morning and the Technical Committees on Scientific and Use Classification of Coal on Thursday afternoon. The Committee on Mining Methods held two general sessions, one for presentation of a half-dozen interesting papers on strictly mining subjects, the other on Aerial Transportation. It also participated jointly in a session on ground movement and subsidence with the committee of that name and the Coal Division The Institute's Standing Committee on Aviation had its inception at the session on Aerial Transportation

Jan 1, 1935

THE 144th* meeting of the American Institute of Mining and Metallurgical Engineers was held in New York, Feb. 18 to 21, 1935. It consisted of the annual business meeting, 45 technical sessions at which 216 papers were presented (approximately the same number of sessions and papers as at the previous annual meeting), two sessions of the Board of Directors, three meetings of Section delegates, two formal lectures and two addresses, luncheon Monday, Tuesday and Wednesday for members and guests, six group dinners and eight group luncheons, ten committee meetings, the annual reception and dinner dance, an informal dance, a smoker-dinner and the annual meeting of the Woman's Auxiliary. Attendance was generally greater than for the two preceding meetings; the statistics follow (figures are in the order 1935-1934-1933); total registration, 1609-1534-1475; dinner dance, 577-543-426; dinner-smoker, 490-425-394; informal dance, 279-295-250; women's registration, 179-160-133; general luncheons, 1132-1034-734. The Coal Division held two general sessions on Monday and a symposium on coal-mine ventilation on Tuesday morning. The Committee on Bituminous Planning, Edward Steidle, chairman, presented a report at the Monday morning session. C. B. Huntress, President of Appalachian Coals, Inc., was the principal speaker at the luncheon on Monday, at which Eli T. Conner, Chairman of the Division, presided. Mr. Huntress was preceded by Howard N. Eavenson, President of the Institute, who spoke briefly. The Sectional Committee on Classification of Coal met Wednesday afternoon. A feature of the meeting concerning three Divisions-Iron and Steel, Institute of Metals, Petroleum-was the symposium on Use of Metals in the Petroleum Industry, Thursday morning and afternoon. Five of the papers presented at this symposium have been published in METALS TECHNOLOGY'. Another feature, of general interest, was the Tuesday morning session in the Auditorium, devoted to Federal Government and Mineral Industries. Dr. C. K. Leith delivered the principal address, on "A, Mineral Policy for the United. States." . The Institute of Metals Division held technical sessions Tuesday afternoon and Wednesday. morning and afternoon and on Thursday

Jan 1, 1936

By R. E. Somers

THE Appalachian field is notable for four tests drilled in recent years to depths of over 7000 ft. and for one commercial gas well at 6822 ft. The latter is the Ligonier well and produces from the Oriskany FIG. I.-NATURAL GAS PRODUCTION OF PENNSYLVANIA AND WEST VIRGINIA. sandstone. Together with several other comparatively deep tests, these holes were drilled in search of natural gas, to make up for the decline in production of the field. The production curve of Pennsylvania FIG. 2.-EAST WEST SECTION OF APPALACHIAN FIELD. (AFTER ASHLEY AND ROBINSON, PENN. G. S.) and West Virginia from 1907-21 is given in Fig. 1 to illustrate the heavy decline from the peak of 1917. This diminishing supply has also been shown by Moyer,1 on the basis of decreasing rock pressures.

Jan 3, 1924

By AIME AIME

ACCORDING to M. Perogordo y Lasso, professor in the School of Mines, College of Engineering, National University of Mexico, what is known a. the "co- operative system" was started there on Feb. 1, 1929. On Jan. 1, 1792, the Real Seminario de Mineria was opened in Mexico City and had much success. Later, the name was changed to Colegio de Mineria. When other branches of engineering were introduced it was known as the Escuela Nacional de Ingenieros, and finally, with the reorganization of the University the

Jan 1, 1929

By T. lkeda, R. S. Montgomery. A. Hara

Actual test specimens used in the previous laboratory wear investigation,' were fully characterized and the data is given in Table 1. Most of the carbides tested could be placed into groups of similar mean grain size. When the wear rates of the members of these groups were plotted as functions of their hardnesses, a family of curves resulted; curves for groups containing data from larger grained composites were at lower wear rates at the same hardnesses. Most specimens tested showed only A-1 porosity (ASTM Standard designa-

Jan 1, 1971

By George M. Humphrey

It is indeed a pleasure for me to have this opportunity to discuss with you a subject which I find infinitely interesting and intriguing - namely, world-wide iron ore supply and demand. We will be examining the following: (i) current iron ore production and requirements; (ii) the major ore producing countries; (iii) the seaborne iron ore trade; (iv) ore grades or types; and (v) future requirements. For those who may not be familiar with the iron ore mining industry, it may be useful to know at the outset that our industry has been plagued with overcapacity for the past seven years. The optimism which prompted substantial expansion of productive capacity in the early to mid-1970's has unfortunately proved to have been unfounded. I shall begin by describing where we are today as well as a little about how we got there. In the latter regard, it's not so much that historical knowledge will solve any of the industry's problems or provide clairvoyance with regard to the future. Rather it's a feeling on my part that some knowledge of the past will provide a useful perspective capable of enhancing our analysis of future trends. At the time of writing, the most recent year for which we have definitive world-wide iron ore production and consumption statistics is 1980. In that year the world consumed approximately 859 million metric tons of iron ore to produce approximately 510 million metric tons of primary iron consisting of 502 million tons of pig iron and 8 million tons of sponge iron. Crude steel production for the same period attained a level of 719 million metric tons. Because it is possible in today's world to produce steel without consuming iron ore simply by melting scrap, the key statistic insofar as iron ore demand is concerned is primary iron production. In 1980 the ratio of iron ore consumption to primary iron production was 1.68:1.00. The comparable ratio over the past seven years has varied from 1.63 to 1.87 and averaged 1.72:1.00. All the same, as a practical matter crude steel production and iron ore consumption tend to parallel one another closely, and for the time being a good rule of thumb is that to produce an average ton of crude steel requires 1.20 tons of iron ore. Let's turn our attention now to the regions where the 859 million tons of iron ore necessary to support 1980 world-wide iron and steel production were produced. Not surprisingly, most of the ore was produced in the same region where it was smelted. In round numbers 65% of the world's iron ore production is currently consumed in the same general region as it is produced, while 35% enters the seaborne trade and is transported in ocean vessels to a more remote consuming area. Approximately 85% of the world's seaborne iron ore trade is directed to the Western European and Japanese markets, both of which are almost entirely dependent on off-shore sources for their mammoth iron ore requirements. The following tabulation lists, in order, the twelve leading iron ore producing countries in 1980 as well as their percentages of total and free-world production; in addition their export potentials are presented. As a group these countries accounted in that year for 89% of world-wide production which stood at 871 million tons. Leading World Iron Ore Producing Countries [ ] One will first note that world iron ore production is dominated by the top four producers - namely, the U.S.S.R., Brazil, Australia and the U.S.A. - which together accounted for nearly 60% of total 1980 production. Of these four major producers the U.S.A. and the U.S.S.R. produce almost exclusively for consumption in their own regions, whereas Australia and Brazil produce primarily for the seaborne export trade. In fact Australia and Brazil accounted for about 50% of all seaborne iron ore trade in 1980! It is also interesting to note that Australia, Brazil, the U.S.A. and Canada accounted for nearly 60% of free world iron ore production in 1980. Once again the importance of Australia and Brazil shows itself, with their share alone of free world production reaching 35%. As has already been noted, a significant 35% of the world's iron ore production in the year 1980 was

Jan 1, 1982

By J. L. Taylor, Pol Duwez

THE present knowledge of the Ti-Al system is limited to the portion of the diagram extending from pure aluminum to the intermetallic compound TiAl3' A preliminary investigation of the titanium-rich Ti-A1 alloys revealed that the solubility of aluminum in titanium is quite extensive and that the transformation temperature of titanium is raised by alloying with aluminum. From an X-ray diffraction study of alloys containing up to 75 atomic pct Al (TiAl3), the phase boundaries at 750°C were located as follows: the a titanium solid solution extends from 0 to about 36 atomic pct Al, a two-phase region exists from 36 to 46 atomic pct Al, and an intermediate phase of varying concentration extends from 46 to 62 atomic pct Al. The purpose of the present paper is to describe the crystal structure of this new phase. The alloys were prepared by melting in a helium arc furnace on a water-cooled copper plate, using a furnace essentially the same as that described in ref. 2. The titanium metal was of the iodide type furnished by the New Jersey Zinc Co., and a piece of pure aluminum (99.99 pct) was obtained through the courtesy of the Aluminum Co. of America. After melting, the samples, weighing approximately 5 g, were sealed in evacuated fused silica tubes and homogenized for 4 hr at 1000°C. The specimens were then held for 10 days at 750°C and rapidly cooled to room temperature. Filings were then taken from each sample, sealed in evacuated vials, annealed at 750°C for 4 hr, and rapidly cooled to room temperature by quenching the vials in water. Powder diffraction patterns were obtained with a 14.32 cm diam camera, using K copper radiation filtered through a nickel foil. Structure Determination The X-ray diffraction patterns of the alloys containing 46, 50, 55. 60, and 62 atomic pct Al were identical, except for a slight shift in the positions of the reflections. The alloy containing 55 atomic pct Al was chosen far structure determination. The powder pattern contained 37 reflections and the a, doublets were well resolved in the back-reflection range. The relatively small number of reflections and the sharpness of the pattern were considered as an indication of a simple atomic arrangement in a relatively small unit cell of high symmetry, and an attempt was therefore made to solve the structure without single crystal work. A satisfactory fit was found on a large scale Hull-Davey tetragonal chart for an axial ratio of approximately 1.45. All the reflections were readily indexed and the tentative unit cell dimensions were computed to be a - 2.81 kX, c - 4.07 kX, and c/a = 1.448. The indices (hkl) and the values of d and sin2 A are given in Table I. The agreement between observed and computed sin2 is quite satisfactory. Once the unit cell was known, the details of the structure were readily found. First, it is obvious that the number of atoms per unit cell cannot exceed two, since more than two atoms would lead to a density greater than that of pure titanium. The next logical step is to assume that the two atoms occupy the corner and center of the cell. If this assumption is correct, the structure may be described as follows: space group D1, - P 4/mmm; one titanium atom in a: 000; one aluminum atom in d: 1/2 1/2 1/2: and no extinctions. Assuming this structure to be the correct one. intensities were computed by means of the usual equation: sin2 0 cos 0 where F is the structure factor; 8, the Bragg angle. and p, the multiplicity factor. The calculated values of intensities are compared in Table I with the visually estimated intensities. The agreement is quite satisfactory and the structure is therefore confirmed. The crystal structure of TiAl just described is the same as that of AuCu ordered. The AuCu ordered

Jan 1, 1953

By D. E. Trout, W. R. Hibbard

Previous investigations have shown that the cold rolling textures1n2 and the drawn wire textures3 of copper change their secondary components after the addition of about 1 pct aluminum and 5 pct zinc, but do not change after the addition of as much as 30 pct nickel. However, few data are available on compression textures. Barrett4 reports from unpublished work with E. L. Layland that compression rolled copper develops a texture which is predominately (110) in the compression plane with a secondary spread to (113) and weaker spread to (100) as shown in Fig 1. However, 70-30 alpha brass similarly treated develops a texture again predominately (110) in the compression plane and with a weak secondary spread to {113} but with moderate (111) secondary intensities illustrated in Fig 2. Experimental Procedure Specimens of the compositions shown in Table 1 remaining from a previous investigation3 were annealed to a grain size of 0.090 mm average diam and machined to cylinders 0.20 in. diam and 0.20 in. high. Cylinders were compressed 90 pct reduction in height between lubricated steel blocks in a tensile machine. Glancing X ray photo-grams using copper K-alpha radiation were taken at an angle of 0 degrees to the compression surface. (111), (002) and (220) rings were analyzed to define the textures shown in Table 1. The results are in agreement with Barrett4 as to types of textures and are essentially in agreement with previous work1,2,3 as to the effects of composition. In the wire study3 it was reported that the 4.99 pct zinc alloy had a brass-type texture, while the data in Table 1 indicate a copper-type texture for compression. The wire specimen of the 4.99 pct zinc alloy was re-examined by X rays and it was established that the [loo] component still exists in the wire axis. Therefore, Table 2 of Ref. 3 is in error and should indicate a double [ill], [loo] copper-type texture for this alloy. This correction results in complete consistency with regard to compositional effects, namely that copper and its alloys containing up to approximately 1 pet aluminum, 5 pct zinc and at least 30 pct nickels develop a copper-type texture and more concentrated copper-aluminum and copper-zinc solid solution alloys will form a brass-type texture. Summary Compression textures developed in copper and its alpha solid solution alloys of aluminum, nickel and zinc are essentially the same types as those re- ported by Barrett4 with compositional effects occurring at approximately the same percent additions as previously reported for rolled sheet182 and drawn wire.3 The Scovill Manufacturing Co., Waterbury, Conn., furnished the copper and brass alloys, performed certain chemical analyses and supplied laboratory facilities where needed. References 1. Brick, Martin and Angier: Tram. A.S.M. (1943) 31, 675. 2. Dahl and Pawlek: Zlsch. Melall. (1936) 28, 266. 3. Hibbard and Yen: Trans. AIME 175, 126. Melals Tech.. Feb. 1948, TP 2334. 4. Barrett: Structure of Metals, mc- Graw-Hill (19421, 386.

Jan 1, 1950

US 4,195,426-Manganese nodules are recovered from relatively great depths on the ocean floor using a self- propelled remote-controlled vehicle having a V-shaped tubular structure with a system of crawlers at its apexes. Underneath each side of the V-shaped structure is a scraping system for gathering nodules and directing them into a tubular conveying system for elevation to the surface ship. A given area of sea bed is fully mined in a single pass of the vehicle. V. Banzoli, V. Di Tella, and P Vielmo, assigned to Tecnomare, SPA. Apr. 1, 1980. 5 pp. 137-60) Filed. 3-31-78 (892,197). Priority: Italy, 4-1-77 (84119A/77).

Jan 1, 1982

By J. F. Kemp

PAGE I. Introduction,.......269 11. Topogmphical Features,.....270 III. Geological Relations of the Mineralized Area,.272 1. Structural Features,.....272 2. Occurrence of the Copper,....274 3. Granite-Contacts,.......274 IV. Descriptions of the Rocks,.....274 1. Granite,........274 2. Limestone,.......276 3. Porphyritic Eruptions,.....278 (a) Quartz-Porphyry,.....278 (b) Trachyte-Porphyry,.....280 V. Contact Phenomena,......285 1. Comparative Immunity of the Limestone, . 285 2. Contact Phenomena in the Quartz-Porphyry,.... 285 3. The Form and Distribution of the Ore-Bodies,290 VI. Method of Deposition,......293 I. Introduction. The White Knob copper-deposits are situated about three miles south of Mackay, on the Salmon River branch of the Oregon Short Line Railroad, in Custer county, Idaho. An outline-map of this district is given in Fig. 1. The deposits have been known and spasmodically worked for many years, and a total of over 3.5 miles of tunnels, shafts and other workings has been driven with a view to their development. These extensive excavations have exposed the deposits sufficiently to permit a careful geological examination. The peculiar features which give special interest to this paper are the branching, tree-like form of the ore-bodies; the absence of zones of secondary enrichment in the partly oxidized pyritic deposits, and the fact that while the deposits are associated in a general way with the contact of an eruptive rock with limeetone, which it penetrates, the garnetization has taken place not in the limestone, as is the usual case, but in the igneous

Jan 1, 1908

By D. F. DeSante, A. S. Tetelman

MICROCRACKS are often introduced into commercial metals during fabrication processes such as swaging, cold rolling, deep drawing, and welding. These microcracks act as strain concentrators and may be capable of causing premature catastrophic failure of a component or weld. The present investigation was undertaken to determine whether high-temperature annealing treatments may be capable of reducing or negating the detrimental effects of such existing microcracks. Internal microcracks, ranging from 0.1 to 0.85 mm in length and averaging 0.23 mm, were introduced into polycrystalline Fe-3 pct Si tensile specimens (0.155 mm grain size) by the cathodic charging of hydrogen.1'2 The typical appearance of such microcracks and their associated strain patterns (made visible by the technique of dislocation etch pitting3) is shown in Fig. 1. The stress fields of the dislocation loops formed during plastic relaxation stabilize the microcracks so that, when the internal hydrogen pressure is removed: the microcracks stay open, rather than disappear as perfectly elastic cracks would be expected to do.' As shown in Fig. 2, such stopped microcracks cause a 36 pct decrease in the macroscopic cleavage fracture strength at -196°C.

Jan 1, 1969

By Henry Howe

FIG. 1 shows a volute aging break which developed spontaneously in a hardened and tempered steel helmet between 19 and 38 days after it had been tested ballistically. A similar break, shown in Fig. 2, developed spontaneously in a similar helmet about 40 days after the ballistic testing. In this case the rupture occurred abruptly and with a loud report. The path of rupture in this second case, though much the less regular, is the more interesting of the FIG. 1. FIG. 2. two, in that it is an approximation to two parallel volutes centered at the point of impact of the projectile, just below D. Several weeks later, after the photograph for Fig. 1 was taken, a similar doubling of the volute crack occurred in this helmet, starting from the end of the eyelash crack near A and spreading thence to the left contra-clockwise for about ½ in. The negatives from which these pictures are made have not been touched up in any way, save writing the letters on them. In both cases the trajectory of the bullet was normal to the initial surface at the point of impact, and in both the helmet passed the ballistic

Jan 2, 1919

By Roy Moore

THE Tom Reed Extension and Big Jim mines of United Eastern Mining Co. are situated in the Oatman district, Mohave County, Ariz., about 28 miles southwest of Kingman, the nearest railway point. Articles descriptive of the mine surface plant, mill construction, and plant operations have been written by Otto Wartenweiler1, the designing engineer; Wheeler 0. North,2 when he was assistant general manager for the company, and Earle M. Bagley, mill superintendent.3 The last article covers average costs for the full time the mill was operated. The geology of the mines is described by F. L. Ransome4 of the United States Geological Survey. Production was started in January,. 1917, and the known orebodies were exhausted in May, 1925, showing a life of seven years and five months. On account of the comparatively short life and the fact that stoping operations were confined to two orebodies, little experimenting was done with mining methods. The two orebodies were in what is generally called the Tom Reed-United Eastern vein, which occupies a fault fissure having a normal displacement of several hundred feet. Seven or eight very productive ore shoots were mined along this vein in a distance of 1 ½ miles, the two worked by the United Eastern being 1 mile apart. The maximum dimensions of the Tom Reed Extension ore shoot were height, 750. ft.; length, 950 ft.; thickness, 48 ft. The vein structure varied from a solid quartz-calcite filling to a series of parallel stringers separated by andesite. From this body, 511,976 tons of ore were mined. (Fig. 1.)

Jan 1, 1928