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The suggestions of the members of the Institute are very much desired by the Committee on Nominations prior to deciding upon its nominations to fill the places of those officers who retire early in 1917. The Committee must make its final report to the Board of Directors early in October. The members are, therefore, asked to send in promptly their suggestions for Directors as well as for Vice-Presidents and President. The Committee hopes to hear from a large number of the members. The officers to be elected at the annual meeting in February, 1917, are: One officer, known as Director and President. Two officers, known as Director and Vice-President. Five officers, known as Director. The attention of members is called to Articles V and VII of the Constitution, and to By-Law XIII, which reads as follows: "The geographical districts to be considered by the Committee on Nominations shall be as follows, until otherwise ordered by the Board. District No. 1. New England, New York, and-New Jersey, excepting New York City and district, which is provided for in the Constitution. (N. B.-New York City and district is designated District 0.)

Jan 7, 1916

The suggestions of the members of the Institute are very much desired by the Committee on Nominations prior to deciding upon its nominations to fill the places of those officers who retire early in 1917. The Committee must make its final report to the Board of Directors early in October. The members are, therefore, asked to send in promptly their suggestions for Directors as well as for Vice-Presidents and President. The Committee hopes to hear from a large number of the members. The officers to be elected at the annual meeting in February, 1917, are: One officer, known as Director and President. Two officers, known as Director and Vice-President. Five officers, known as Director. The attention of members is called to Articles V and VII of the Constitution, and to By-Law XIII, which reads as follows: "The geographical districts to be considered by the Committee on Nominations shall be as follows, until otherwise ordered by the Board. District No. 1. New England, New York, and New Jersey, excepting New York City and district, which is provided for in the Constitution. (N. B.-New York City and district is designated District 0.) District No. 2: Pennsylvania.

Jan 6, 1916

By TRUMAN S. FULLER

THE GREAT INTEREST in decomposition and trans- formation, so evident in the study of alloys during the last two years, was reflected in the many papers on this subject, presented at the first session of the Institute of Metals, Tuesday morning. Dr. F. A. Thomson, of Montana State School of Mines, presented the first paper by C. Wilson, H. F. Silliman, and E. C. Little, "Rate of Precipitation of Nickel Silicide and Cobalt Silicide in the Hardenable Copper-nickel-silicon and Copper- cobalt-silicon Alloys." Dr. R. F. Mehl, in discussing this paper, stated that the title was somewhat deceptive, as it indicated that the rate of precipitation is determined; the method used is a measurement of electrical conductivity and hardness, neither of which is suitable for a quantitative measurement of rates of reaction or precipitation in the solid state. Hardness is also uncertain because it depends so much upon particle size. Of the various methods proposed for the study of rate of reaction and precipitation the evaluation of volume of reaction produced from the area of photomicrograph is the best.

Jan 1, 1933

By J. D. Meakin

J. D. Meakin (The Franklin Institute Laboratories)— In a recent paper Garofalo12 has shown that a number of experimental creep results can be represented by the empirical relation In this expression ? is the steady creep rate, s is the applied stress, and A is a constant at a given temperature; a and n are adjustable parameters. Garofalo has shown that Expression [6] approximates to a power function at low stresses and a simple exponential function at high stresses. Among the data used by Garofalo are the results we published for creep of copper." For these results we found that the best correlation was an exponential law with different parameters in the low-and high-stress region, respectively. That is, i = A exp qs where A and q have different values above and below a critical stress a,. In Ref. 13 are listed a variety of observations which support the proposal that different mechanisms are operative at stresses above and below a,, and it is not felt appropriate to repeat those observations here. The purpose of this note is to demonstrate that, although the representation used by Garofalo does fit the experimental data very well, this fit cannot be used to conclude that only one mechanism is rate-controlling. The argument is best made graphically and is illustrated in Fig. 9. The continuous curves 2 and 3 represent pairs of simple exponential functions which intersect at i = 10-5. The curve 2 closely resembles the copper results in that a change of slope of 2:1 occurs at i = 10-5; the two functions shown are in fact: e = 10-7 exp (1.150) and ? = 10-6&apos; exp (0.576s) For purposes of comparison, curve 3 represents two exponential functions with a change of exponent of 3:1 and curve 1 has the exponent 1.150 throughout. It is quite clear that a satisfactory straight-line fit is obtained on a Garofalo plot for all three curves. The curves represent processes which have either a single stress exponent or two ex- ponents in a ratio as high as 3:l. It must, therefore, be concluded that the ability to obtain a linear dependence between log i and log (sinh cyo) cannot be taken as evidence for a single activated process. In fact, to some extent the way the experimental points quoted by Garofalo lie about a best fit straight line on the log (sinh as) plot indicates that two processes are indeed occurring. This is seen in Figs. 7(c) and 8(c) of Ref. 12 where it is particularly evident that the experimental points deviate from the straight line in a manner similar to curves 2 and 3 of Fig. 9. It is, of course, recognized that the generally used exponential form is an approximation to the hyperbolic sine function which is not valid for exponents of less than 1.2, e.g., qs < 1.2. The only curve in Ref. 12 which is affected by this restriction is Fig. 6(b) where the deviation from a In ? vs s

Jan 1, 1964

By AIME AIME

AT the meeting on Engineering Education on Mon- A day afternoon E. A. Holbrook, of the University of Pittsburgh and chairman of the Committee, presided as chairman with W. B. Plank acting as vice- chairman. About sixty members of the educational fraternity were present. Dean Holbrook, after a few introductory remarks, introduced the first speaker of the afternoon, Charles Y. Clayton, who then presented his paper, "Why Do So Few Elect Metallurgy?" in which he stressed the fact that ,one of the things the study of metallurgy ,now needs is publicity and public education on what metallurgy is and &apos;does. Another thing he brought out is that the study of metallurgy has been looked on for many years merely as a branch of other departments. He gave tables showing past and present enrollment in the course of metallurgy in various schools.

Jan 1, 1930

By J. C. Bierlein, R. A. Dodd

Endurance strengths at 10&apos; cycles, fatigue-hardening rates, and endurance strength/0.2 pct proof stress ratios have been determined jbr a range of Cu(Ni), Cu(Si), and S.R.0. Cu(Au) solid solutions. Some douht is cast on simple cross slip models of fatigue hardening in view of opposite composition dependencies of hardening displayed by Cu(Si) and Cu(Au). The temperature dependencies of hardening also are the opposite of predictions made on the basis of a cross slip model. A correlation apparently exists between the fatigue strength/0.2 Pc~ proof s1.re.s~ ratios and rates of fatigue hardening. An increase in PS/PS due to alloying or temperature change is accompanied by a decrease in hardening rate, and vice versa. In recent years there has been much interest in the determination of the dislocation structure of fatigued metals and alloys. The accumulated evidence, e.g., Refs. 1 to 5, suggests that the structure may be dependent on the stacking fault energy, 7, of the fatigued metal in the same way that fatigue hardening rates have also been shown to apparently depend on u .6&apos; 7 The above research followed the various earlier theories relating crack nucleation to ease of cross slip, e.g., Refs. 8 to 131 so "ggesting that y may indeed be the parameter of principal significance in all facets of the fatigue process. However, comparatively little attention has been paid to correlating engineering fatigue data with observations of the above type. Certainly, it would be useful if potential engineering fatigue performance could be assessed from a knowledge of easily determined alloy properties, and the present research originated from this standpoint. TO investigate the widest Possible range of 7 would require the use of two solvent bases, e.g., aluminum and copper, but a reasonable coverage can be provided by copper-based solutions alone. Therefore, it was decided to work with Cu(Ni) and Cu(Si) solid solutions, the approximate stackillg fault energies of which are given in Table I. The y range extends from low, Cu(7.5 at- Pet Si), to moderately high in Cu(2-5 at. ~ct ~i) and two of the Cu(Ni) alloys. The values listed in Table I should be regarded as qualitative only, being derived as follows. Dillamore and smallman14 quote a value of 85 i 30 erg.cm-2 for the stacking fault energy of pure copper, based on an earlier value due to Howie and swannl5 corrected by Brown&apos;s formula.&apos;&apos; Since the ratios (alloy)h(pure copper) have been reported17,18 for Cu(Ni) alloys containing up to 30 pct Ni, approximate ) values for these alloys can be computed, and a rough estimate of 7 for Cu(50 at. pct Ni) obtained by extrapolation. The relatively low y value obtained in this way for Cu(50 at. pct Ni) coincides with the observation of Nakajima19 that the stacking fault probability is a maximum at this composition. Likewise, the y values for the three ~u(~i) alloys are estimates based on values given by Swann and Nuttingo corrected on the basis Of Brown&apos;s estimate that the true 7 values are probably 2.3 times greater than those originally computed. In addition to the above alloys it was decided to investigate short-range ordered (s.R.O.) CU(AU) alloys containing up to 25 at. pct Au. This last alloy has been shown to have a well-defined planar arrangement of dislocations when deformed,21,22 probably due to cross slip being restricted by the S.R.O. Engineering fatigue data was to be represented by the determination of endurance strengths, and these were to be correlated with fatigue hardening and mechanical property data. EXPERIMENTAL I, order to study the desired properties and property changes, the following alloys were prepared: Cu(2.5 at. pct Si), Cu(5.0 at. pct Si), Cu(7.5 at. pct Si), Cu(5.0 at. pct Ni), Cu(25.0 at. pct Nil, Cu(50.0 at. pct Ni), Cu(5.0 at. pct AU), Cu(15.0 at. pct AU), Cu(25.0 at. pct AU). The copper and gold were zone-refined, while the silicon was semiconductor grade. The nickel was of 99.95 p,t. purity.* All alloys were induction-melted in a *Kindly supplied by the International Nickel co. helium atmosphere, appropriate precautions being taken to avoid segregation in the Cu-Au series. Rod stock was obtained by rolling and swag,ng. A few Bridgman single crystals were grown for fatigue-hardening studies, but most material was machined into polycrystalline fatigue speciments of the design shown in Fig. 1, and into polycrystalline tensile and fatigue-hardening specimens of simple cylindrical design. All specimens except Cu(Au) were annealed; the latter were quenched from above T, to produce short-range order. A few of the quenched alloys were examined for long-range order by step-scanning over

Jan 1, 1969

By R. S. McClellan

DURING the last year or so, with higher prices for gold and silver, many old properties in the West have come back to life. Almost every profitable producer in the old days has been considered, and the reasons for its shut-down investigated. If it seems likely that modern ore-finding, mining, and metallurgical methods, and S35 gold can again put the property on a profitable basis, someone can usually be found to back the venture. Methods of rejuvenation vary with the property, of course, but the following outline of what has been done with one group of mines in Idaho is fairly typical and may be suggestive to others. The Golden Chariot gold-silver properties, near Silver City, consist of seven old mines, working a vein system striking north and south, which had a productive length of some 3500 ft. The vein is a quartz-filled fissure with granite walls. Gold occurs in native, and with silver in the form of electrum which is the natural alloy of the two metals. Silver also occurs in a variety of sulfides. From 1064 to 1876, these old properties were worked intensively to an average depth of about 700 ft., through seven shafts which range in

Jan 1, 1934

By Philip D. Wilson

WHEN the United Nations win the war and the decision has been made to control future armament in the Axis countries, plans for the extent and operation of such control must have been prepared, to be ready to put into immediate execution. Such control to be effective must be premised upon complete military occupation of the two countries for a substantial period, with an arrangement at the end of such occupation for continued supervision of these industries into an indefinite future.

Jan 1, 1944

By V. C. Rogers

ALTHOUGH surveying at mining properties is fundamentally the same regardless of the method of mining, at Climax, due to the nature of the ground, the policy of advance development work, and extremes in climatic conditions, surveying practice has had to be revised to meet the specialized conditions of this particular type of mining operation. The company&apos;s mine is one of the largest underground properties in the United States. It has proved ore reserves of 275,000,000 tons, 60,000,000 tons of which have been broken. To date, 109,000 ft. of development drifting have been driven, as well as 40,926 ft. of development raising, 10,000 ft. of ventilation drifting and raising, 16,000 ft. of exploration drifting, and 206,000 ft. of diamond drilling. Normal production varies between 1.2,000 and 15,000 tons daily. Development work proceeds at a rate of 11/2 tons developed for every ton milled and with a development of 18,000 to 20,000 tons per day, the following crew is required to take care of mine and surface engineering

Jan 1, 1946

By Alexander Anderson

TABLES showing the drift and inclination of wells surveyed in the years 1924 to 28&apos; and in the year 1929&apos; have already been published. Each of these tables included a little over 1,000,000 ft. of rotary hole. In the year 1930 the table -shown-in . Fig. 1, comprising, the results of surveys .of 1,030,344 ft. of hole and representing 11,642 individual survey readings, was compiled. For that purpose we selected &apos;I only wells that had been drilled in California during that year. The footage of Fig. 1 differs from the two earlier tables in that the wells were all drilled in the year 1930. In the earlier tables, the footage shown was surveyed in the years designated, but some of the wells were drilled in earlier years.

Jan 1, 1931

By John V. Beall

TOO early spring may be the explanation for the poor turnout of mining and metallurgical engineer candidates at a large New York guidance conference, but it would be wiser to take a more serious view of this occurrence. Held a few weeks ago, the meeting was preceded by weeks of preparation and publicity in which many engineering societies participated. The meeting was the First Greater New York University downtown campus for splitting up anticipated to draw about 20,000 high school students from the New York area and environs. Seven of the theatres in the Paramount chain were avail- able to hold the audience for a panel program on career opportunities which was to be televised and piped into the theatres. Following the morning theatre session, students were to adjourn to the New York University downtown campus for splitting up into workshop sessions devoted to seventeen different branches-of the profession.

Jan 5, 1953

By Y. C. Liu

The orientation relationship between the dejormation and recrystallization textztres of binary Cu-P alloys of high phosphorus content was observed to he a ± 14-deg (110) rotation. According to the ori-ented-gvowth hypothesis, the same relationship should exist between a successfully flowing pain and the strained single-crystal matrix of alloys of corresponding composition. The orientations of thirty successfully growing grains were obtained in a Cu-1.0 at. pct P alloy. Both a conventional analysis and the more detailed analysis advanced in the present study demonstrate that the observed orientation relationship is not comparahle to that predicted by the oriented growth hypothesis. IT has been shown experimentally that the formation of recrystallization textures in metals may be explained on the basis of the oriented-growth hypothesis. This conclusion is based primarily on the results of cooperative experiments carried out by various investigators in aluminum. Beck and HU&apos; suggested that the orientation relationship between the recrystallization and deformation textures of aluminum is a 38-deg(111) rotation. A similar relationship, i.e., a 40-deg(111) rotation, was observed between the primary and secondary recrys-tallization textures.&apos; Since the secondary grains result from a process of selective growth, this naturally implies that the same mechanism is also responsible for the formation of the primary re-crystallization texture from the deformed matrix. Further evidence was provided by the experiments of Liebmann, Liicke, and Massing3 and Yoshida, Liebmann, and Lucke.4 They observed that grains which could successfully grow into strained aluminum single crystals invariably exhibited the same orientation relationships with their matrix. Thus, regardless of other opinions,5&apos;9 these results offered good evidence in favor of the oriented-growth hypothesis. In order to examine broader applications of this oriented-growth hypothesis, experiments should be carried out in metals other than aluminum. In a recent investigation on the recrystallization textures of binary copper alloys with phosphorus, arsenic, and antimony,7 it was found that the predominant recrystallization components were related to the deformation textures by a (110) rotation. The (110) rotational relationship is different from the (111) relationship generally proposed between the recrystallization and deformation components of other binary copper alloys. 1,8,9 Applying the observations made for aluminum, the oriented-growth hypothesis predicts that the orientation relationship of grains successfully growing into the strained single crystals of either one of these copper alloys should correspond to that observed in the textural study. Verification of this prediction would provide a critical test of general applicability of the oriented-growth hypothesis to the formation of recrystallization textures in fcc metals other than aluminum. The Cu-1.0 at. pct P alloy was selected in the

Jan 1, 1964

By A. H. Daane, B. J. Beaudry

The uranium-antimony system has been investigated by metal-lographic, therma1, and X-ray methods. There are four intermediate phases present: USbz and U,Sb, which undergo peritectic decomposition at 1355°and 1695OC, respectively, and USb and UPSbs which melt congruently at 1850"and 1800°C, respectively. There is a eutectic between U4Sbs and USb which melts at 1770°C. USb,, UsSb4, and USb are line compounds while U4Sbs has a solubility range of approximately 1.5 at. pct at 1770°C. Single crystal studies of the cmpo,und U.,SbS show it to have a hexagonal unit cell with a, = 9.268A and c, = 6.201b;. The solubility of uranium in liquid antimony increases from 0.1 at. pct at 650°C to 1.5 at. pct at 900°C. The solubility of antimony in a, P, and y uranium is approximately 0.02, 0.1, and 0.05 at. pct respectively. IN nuclear reactors, uranium has been used mainly in the form of solid-fuel elements of the pure-metal or uranium-rich alloys. However, in attempts to overcome some of the difficulties inherent in solid-fueled reactors, reactor concepts hive been proposed in which the fuel would be a liquid metal, such as a solution of uranium in another metal. The liquid-metal fueled reactor (LMFR) designed by the Brook-haven National Laboratory of the U.S. Atomic Energy Commission is an example. Fuel for this reactor is a solution of approximately 800 ppm enriched uranium in bismuth.&apos; To design such liquid-fueled reactors, a background of information on the solubility of uranium in various metals is obviously necessary. The present study was undertaken to pro- vide information for such purposes, and in addition, to study the uranium-antimony system as a whole. A preliminary literature search showed that some work had been done previously on uranium-antimony alloys, but no attempts had been made to make a complete study of this system. The solubility of uranium in antimony was studied by Cammack and Bridger&apos; up to 950°C and by Hayes and Gordon up to 900&apos;-C. Their data are plotted in Fig. 1. Ferro, in an X-ray structure study of some uranium-antimony compounds, found USg to be tetragonal with a, = 4.2724 and c, = 8.471A, U3S4 to be b.c.c. with aO = 9.095A and USb to be f.c.c. with a,= 6.191A. Colani reported the compound UsSba; however, work by Ferro and by this Laboratory showed that this compound does not exist. foote&apos; reported several intermediate phases in the uranium-antimony system, but did not identify them. Greninger&apos; re-ported finding an intermediate phase in a 5 at. pct Sb

Jan 1, 1960

By K. A. Gschneidner, O. D. McMasters

DgIel-ential thermal, nretallographic, and X-ray paramzetric methods were used to establish the Yb-Pb phase dingram. The terminal solid solubilities in the system are less than 0.2 at. pct. Lead additions lower the 792°C transformation tewzperature of pure ytterbiun~ at 787°C by means of an inverted peritectic veaction. Ytterbium additions raise the 327oC melting point of lead to 329°C by means of a perilectic reaction. Three intermetallic compounds Yb2Pb, YbPb, and YbPb, melt congruerttly at 1246", 1116o, and 740°C. respectively. YbsPb3 forms by a peritectic reacliorz at 1250°C. YbzPb crystallizes in the PbCh (C23) type structure and the orthorhombic latliceo constants are a, = 7.478. bo = 5.225, aud C0 = 9.549A. YbsPbs crystallizes in the hfnsSi3 (D8a) type structure. The hexa~nal lattice constants for this phase are a, = 9.325 and co = 6.92d. YbPbl crystallizes in the cubic AuCU3 (Ll2) type structure with a: = 4.8628 + 0.0008A. YbPb is diwrorphic with the structure change occurring al 507°C upon healing. The crystal structures of the two forttzs were not determined. Eulectic reactions occur at 5.1 at. pct Pb and 769oC, 41.5 at. pct Pb and 1086oC, and G8.0 at. pct Ph and 717°C: RELIABLE information concerning the alloying behavior of most of the rare-earth metals is scarce. A systematic study of the rare earth-lead alloy systems now in progress is an effort to supply such information. Determination of the phase diagram of the Yb-Pb alloys is the first step of this study. Variations in the valence of normally divalent ytterbium may be studied by comparing the characteristics of the Yb-Pb alloys to those of the trivalent rare earth-lead and of the divalent alkaline-earth-lead systems. Of particular interest are the melting temperatures of the intermetal-lic compounds since these are known to be high relative to the melting points of the constituent metals. Crys-tallographic and magnetic susceptibility data for the rare earth-lead alloys are to be included in the comparative study. Results from this and subsequent investigations should provide a better understanding of alloy formation. EXPERIMENTAL PROCEDURE Materials. The major impurities in the ytterbium and lead used in this investigation are listed in Table I. The lead was obtained from Cominco Products, Inc., and was specified to be 99.99 pct pure. The ytterbium was prepared in this laboratory by the lanthanum reduction of the oxide followed by a distillation of the ytterbium. Alloy Preparation. The alloys were prepared by

Jan 1, 1968

One of the best known of the early mining districts of Nevada was that at Eureka, where gold was first produced in 1864. While the most productive period for the district was during the early 1900s, production was maintained until World War II. During this time it is said that the Eureka district produced as much as $200 million from over 3,200 km (2,000 miles) of tunnels and workings. The Windfall Mine was discovered in 1902; and a 100 ton cyanide plant was operated there during the periods 1907 to 1912 and 1932 to 1940. Since 1974, however, Windfall Venture has been operating a unique heap leaching facility on the site of the old Windfall Mine. Gold at the Windfall occurs primarily in the Cambrian Hamburg dolomite which has been "sanded" and in which the original cementing material has been destroyed. The gold is micron sized and is accompanied by anomalous amounts of arsenic and mercury; however, the ore is low in base metals which distinguishes it from the typical Eureka district ores. Mining the ore causes it to break down into very fine sizes, approximately 50% minus 150 microns (100 mesh). Conventional heap leaching by spraying proved to be impossible; and extensive test work on alternate methods, aided by the United States Bureau of Mines, was conducted using 9 m (30 ft) high columns and then large tonnage heaps. The leaching procedure adopted was to build 10.6 m (35 ft) high heaps on a 50 mm (2 in.) asphalt pad covered with a layer of gravel for drainage assisted by perforated pipe drains and gravel-packed sumps. A berm is constructed around the top of each pad and cyanide solution is allowed to “pond” on top of the heap. The resulting percolation is at the rate of 24 liters per sq m per hr (0.6 gal per sq ft per hr), a figure about 2.4 times the average used in other heap leaching operations. The dolomite furnishes its own protective alkalinity and no lime or caustic is used in the solution which contains 0.4 kg per mt (0.8 lb per st) of NaCN. Pregnant solution from the heaps averages about 0.7 g Au per mt (0.02 oz per st) with a cyanide content of about 0. 2 kg per mt (0.4 lb per st) and a pH of plus 9. Addition of NaCN brings the pH of the leach solution up to 11 to 12. Carbon adsorption of the gold was originally done in six enclosed columns mounted in a trailer but five conventional columns have been substituted as the size of the operations has increased. Carbon stripping is with hot caustic, cyanide and 10% ethanol solution. The

Jan 1, 1981

By Severn P. Brown

Search for ore continued at a feverish pace-as can be attested to by anyone who has tried to arrange for extensive diamond drilling. The stakes are high, and so is the cost as was indicated by Selco Exploration Ltd. when they announced discovery of base metal sulfides at Uchi Lake in northwestern Ontario. It was apparently their first commercial find after 15 years of exploration at a cost of more than $10 million. For the first time in many, many years the big exploration news has come from east of the Mississippi River. In January, the New Jersey Zinc Co., in an unusually worded press release, stated that they had made a major zinc discovery of 13-50 million tons of ore averaging 5-10% Zn. New Jersey&apos;s holdings are said to embrace 500 sq mi. The ore was discovered in eastern Tennessee in the upper part of the Knox dolomite of early Ordovician age. Reportedly the mineralization is at depths of 900 to 2000 ft. Currently about 20 diamond drills are working the area for New Jersey. At least nine other major companies are prospecting the region, which now includes parts of Kentucky. Five hundred thousand acres are said to be under lease. Greatest activity is clustered around Carthage, Tenn. In Missouri, the St. Joseph Lead Co. announced plans to develop a new mine in the Brushy Creek area of the "New Lead Belt." copper and zinc concentrates will be by-products.

Jan 1, 1970

By J. B. Morrow

AMONG the most notable of Canada&apos;s many contributions to the personnel of the mining industry in the United States is J. B. Morrow, born in Halifax, Nova Scotia, April 9, 1886. Soon after completing his schooling at Dalhousie University in 1906 he emigrated to Arizona and Kew Mexico, via Cobalt and Larder Lake, Ontario. After preliminary experience in sampling and mucking he was employed by the Phelps Dodge Corp., first as chemist at the Copper Queen smelter, then, in 1908, with the Corporation&apos;s Stag Canyon coal branch at Dawson, N. M., in various capacities fro111 chemist to coke oven and coke department superintendent, and finally as general outside superintendent. While with Phelps he had some contact with the late Dr. Douglas, of whose industrial methods he has always been a great admirer.

Jan 1, 1937

By Frank C. Kelton

It is perhaps not widely realized that extraction and saturation processes carried out on oil well core samples alter the properties of these samples to varying degrees. On the other hand it is felt by some that quick-freezing of core samples increases their permeability and porosity significantly. Accordingly, laboratory tests were carried out on 49 pairs of horizontally adjacent samples in order to differentiate between the effect of quick-freezing per se on permeability and porosity of the samples, as distinguished from the effect of the identical saturation treatment on permeability and porosity of the companion samples. Also, additional field data were obtained on comparison of frozen vs unfrozen companion samples. LABORATORY INVESTIGATION OF FREEZING us SATURATION EFFECTS Procedure The samples used in these tests were two-cm cubes cut in horizontally adjacent pairs from cores from eight Gulf Coast and Mid-Continent wells, which cores had not previously been frozen. These samples were extracted with carbon tetrachloride, dried, and air permeabilities run in the conventional manner. They were then evacuated and saturated with brine of 25,000 ppm sodium chloride content, and porosities determined by gain in weight. The samples were partially desaturated by evaporation down to an average brine saturation of 68 per cent. One sample from each pair was quick-frozen by covering with dry ice after wrapping in a single layer of paper, and allowed to remain frozen for about two hours; the companion sample from each pair was not frozen. After thawing the frozen sample, all samples were immersed in tap water overnight in order to leach out most of the brine. Air permeabilities were re-run, and the samples were again saturated with brine to determine a second porosity value. For purposes of averaging of data, the samples were grouped according to four permeability ranges, from 0 to 10, 10 to 100, 100 to 1,000, and 1,000 to 3,840 md. Average permeability and porosity changes for the frozen vs the unfrozen adjacent samples are shown in Table 1. Discussion As may be seen from Table 1, the averages of the per cent permeability increases for the quick-frozen samples ranged from 3.8 to 12.9 per cent among the four permeability groups. The average changes among the four groups of unfrozen companion samples ranged from a decrease of 0.2 per cent to an increase of 9.3 per cent. There was no particular correlation of these changes with magnitude of permeability; however, the increase for each group of frozen samples paralleled the increase for the corresponding unfrozen samples. The differences between the two sets of values are believed to be a valid indication of the effect of the quick-freezing in itself, since the treatment of the two samples in each pair was identical except for freezing. The permeability changes which are strictly the result of the quick-freezing are shown in the sixth column of Table 1. These range from a decrease of 0.9 per cent to an increase of 4.0 per cent; the overall weighted average is 1.2 per cent, as compared to an average increase of 6.8 per cent caused by the saturation treatment of the samples not frozen. The average porosity changes are in general smaller than the changes in permeability, and range from a decrease of 2.3 per cent to an increase of 3.3 per cent. The overall weighted average change ascribed to the quick-freezing is 1.0 per cent of porosity. Many factors can contribute to the changes in permeability and porosity observed when subjecting cores to the simple processes used in these tests. Such are: hydration and swelling of clay, adsorption of ions, changes in surface structure and wettability, expansion and compression effects due to ice formation, shrinking and cracking, leaching of salts and colloids, displacement of particles resulting in either blocking or enlarging of pore openings. Whatever particular mechanisms are involved. however, it is apparent not only from this study but also from other investigations in the literature&apos; not directly concerned with quick-freezing, that the effects produced by commonly used extraction, saturation and drying techniques may be of considerable magnitude The results of this study indicate that for the particular samples and techniques used, such effects are of the order of five to six times the effect of quick-freezing. insofar as changes in permeability are concerned. It may be argued that these samples might not include extremely shaly material where the effect of freezing upon permeability may be much greater. However, had such material been available for these tests, it would undoubtedly have been very susceptible also to alteration by the extraction and saturation treatment used. To investigate this point further, the individual sample data were re-grouped according to the magnitude of the average per cent permeability increases for the pairs of samples, irrespective of permeability. The results

Jan 1, 1953

By M. C. Udy, P. C. Rosenthal

THE use of minute boron additions to steel has been given considerable attention in recent years. Comparisons made between boron-free and boron-containing heats of otherwise identical analysis have indicated, beyond a doubt, the potent effect of boron for increasing hardenability. The actual hardenability increase has been expressed as a multiplying factor, or in terms of the percentage of other alloying elements boron might replace, The present study presents the results of a systematic survey of. the use of boron as an addition to two types of alloyed steels and as a replacement for various percentages of molybdenum in these steels, Both cast and wrought steels of the two basic compositions were prepared. Molybdenum, because of its scarcity at the time the investigation was started, was selected as the element to be replaced by boron. Attention was also given to the effects of boron on other properties of the steels, particularly their notched-bar toughness, to investigate other advantages or limitations of this element as an alloy addition. EXPERIMENTAL WORK Steels Investigated The two basic compositions used in this survey of boron as a replacement for molybdenum are given in Table I. The cast steels were higher than the wrought steels in silicon content to improve the casting quality. [ ] Each of these base steels, both cast and wrought, was made with molybdenum contents of o, 0.10, 0.20, 0.30, or 0.40 per cent, the total comprising 20 steels. In addition, each of these 20 compositions . was prepared with boron additions in amounts of 0.0015, 0.003, and o,006 per cent as ferroboron; and in amounts of 0.002 and 0.005 per cent as two com¬mercial intensifier alloys, designated alloys A and B. The boron-treated steels totaled 100, and the entire series 120, Test Procedure Each steel was melted as an individual heat in a 50-lb., magnesia-lined induction furnace. Ingot iron scrap or mixtures of ingot iron and steel scrap were used for melting stock. Deoxidation was carried out in the furnace with o.10 per cent aluminum. The aluminum addition was

Jan 1, 1946

By Leroy U. Gardner

EVERY reader of this paper is well aware of the fact that the prolonged inhalation of large amounts of free silica dust results in fibrosis of the lungs, and that other inorganic dusts, except those of asbestos and the mineral poisons, are thought to be relatively harmless. But probably few have had opportunity to visualize the effects of silica, asbestos and other minerals upon living tissues. The ideal demonstration would be based upon sections of lungs from human beings that had inhaled com- parable concentrations of different dusts for a unit period of time. Such material is generally difficult to obtain and in some instances is of questionable value because the subject has been exposed to more than one kind of dust. A demonstration could be prepared from the lungs of animals. However, so many months or even years are required to complete the exposure to each kind of dust that enough material has not been accumulated. For a general survey of the action of different types of dust, I am therefore compelled to use the tissues of animals that have been injected with suspensions of dust particles. The injection method offers certain advantages. The quantity, the particle size and the state of dispersion can be controlled with sufficient accuracy so that the tissue responses to different minerals can be accurately compared. The method insures contact between the tissues and the mineral particles; protective mechanisms, which may prevent the inhalation of certain types of foreign body, never come into play. If the pathway of injection be one that minimizes nonspecific injury, the tissue responses may simulate those produced by inhalation but they develop somewhat more rapidly. It should always be remembered that injection methods merely demonstrate the capacity of various kinds of minerals to provoke reaction in the tissues; whether the same substances are inhaled from atmospheric suspension and accumulate in the lungs in dangerous quantities can be demonstrated only by inhalation. The reactions that I shall discuss first took place not in the lungs but in the liver. For the purpose in hand this is quite immaterial for we are merely seeking to discover whether these minerals are capable of produc-

Jan 1, 1938