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By G. C. Weaver, G. T. Harley

BEDS or lenses of potash and magnesium salts are found in a thick salt section (Salado) overlain by Rustler Red Beds in several members of which water is present and from one of which the refinery process water used by International is obtained. Most of the holes drilled are less than 1000 ft. deep, but some wildcat holes have exceeded 3000 ft. Cable or rotary tools are used to drill down to the salt. When samples of water are desired the cable rig is used, but when this is not necessary, and where caving material is present, the rotary rig has an advantage. The rotary rig has a further advantage in that only one machine is required to drill and core the entire hole, whereas the cable rig must be moved off to make way for the core drill. Casing is placed in the upper section of the hole as required to shut off water, and a 5 3/16-in. string is set in the top of the salt before coring starts. With the rotary rig drilling is often carried to the salt with no casing, as drilling mud seals off caving ground and water-bearing strata, and a string of 4-in, line pipe or 4-in. flush-joint casing is landed on top of salt. Several types of gasoline-powered core rigs have been used in the field and all recover a 2 1/2-in. core. More recently the Sullivan Model 37 rotary rig has been tried, and a Sullivan Model N has been adapted to use a rotary bit in the upper section. Core is recovered in 20 ft. sections with a double-tube core barrel, and the bit used is a bottom-discharge type set with diamonds. The drilling fluid must be a saturated brine to prevent solution and etching of the minerals present. Blowouts are apt to occur from nitrogen gas trapped under the several polyhalite beds, and some have been strong enough to blow the tools out of the hole. Core recovery is practically 100per cent. All holes are plugged after drilling, with cement through the salt section and opposite each water horizon, and mud through the remainder of the hole. Cores are carefully logged and preserved, and in sections containing potash and magnesium minerals they are quartered and analyzed. The correlation of ore beds between drill holes is briefly described.

Jan 1, 1946

Foreword—H. Foster Bain........................ 7 Officers and Committees......................... 9 PAPERS Growth of Metallic Crystals. By C. H. Desch...............13 Aluminum Castings of High Strength. By R. S. Archer and Zay .Teffries (With Discussion).............................35 Constitution of Alloys of Aluminum, Zinc and Tin and Aluminum, Zinc and Cadmium. By V. Jares.......................65 Exudations on Brass and Bronze. By W. B. Price and A. J. Phillips (With Discussion)..................•..........80 Preparation of Metallic Single Crystals and Twinning in Zinc and Zinc Single Crystals. By 0. E. Romig (With Discussion).............90 Plastic Deformation of a Zinc Single Crystal. By S. L. Hoyt (With Discussion) 116 Plastic Deformation of Coarse-grained Zinc. By C. H. Mathewson and A. J. Phillips (With Discussion)......................143 The Solidus Line in the Lead-antimony System. By E. E. Schumacher and F. C. Nix (With Discussion)........................195 Note on the Distribution of Energy in Worked Metals and the Effect of Process Annealing Temperature on the Final Annealing Temperature of Fine Copper Wire. By L. Zickrick and R. S. Dean (With Discussion)........207 Note on the Relation of Annealing Temperature to Conductivity of Copper Wire. Ry J. C. Bradley (With Discussion)..................210 Beryllium-copper Alloys. By W. H. Bassett (With Discussion)........218 Some Comparative Properties of Tough Pitch and Phosphorized Copper. By W. R. Webster, J. L. Christie and R. S. Pratt (With Discussion).....233 A Study of the 470" C. Transition Point in Cast 60:40 Brass. By Frances Hurd Clark (With Discussion).......................253 Strldy of the Heat Treatment, Microstructure and Hardness of 60:40 Brass. By Frances Hurd Clark (With Discussion)...............276 Corrosion and Physical Properties of Some Alloys of Aluminurn, Zinc and Tin. By N. 0. Taylor (With Discussion)..................302 Equilibrium Relations in Al-Mn Alloys of High Purity. By E. H. Dix, Jr., and W. D. Iieith (With Discussion)....................315 Deformation of an Aluminum Alloy by a Constant Load. By C. B. Sadtler and J. L. Gregg (With Discussion)....................336 Still Casting of Metals. By P. H. G. Durville (With Discussion).......343

Jan 1, 1927

By F. H. Wilson, R. M. Brick

WITH the papers of Palmer and Smith1 and of Burghoff and Bohlen,2 published in 1942, understanding of the problem of the development of ears on deep-drawn brass cups was brought to the point where, from a practical standpoint, producers of brass sheet could keep earing under control. However, these very practical results raised questions concerning the reasons for the observed behavior. Since plastic deformation is fundamentally a function of crystallographic slip, these reasons must be considered in the light of the textures to be found in the annealed sheet. Various attempts have been made to interpret the mechanism of ear formation by correlation with the preferred orientation and the anisotropy of the sheet. However, none of these has satisfactorily explained why ears are usually found in the rolling and transverse directions for copper but at 45° to these directions for brass. This paper offers additional data on these two related subjects and has been divided into two sections. The first section provides a survey of the recrystallization textures of brass as affected by annealing temperatures and prior reductions, and an account of the earing behavior which accompanies these textures. The second section reports new data on the anisotropy that accompanies a characteristic texture for brass and endeavors with partial success to establish the factors that account for the difference in earing behavior between copper and brass. EARING BEHAVIOR OF BRASS Review of Textures The recrystallization texture of severely rolled brass was first reported by Bass and Glocker.3 The preferred orientation to which this texture, obtained from metal annealed at 500°C., was most akin was (113)[112]. This texture has been confirmed by Bauer, von Göler and Sachs;4 Brick;* Brick, Martin and Angier;6 and Cook and Richards7 who, in general, used annealing temperatures under 500°C. Bass and Glocker3 also reported the recrystallization texture at 850°C. to be the same as at 500°C. They analyzed their textures by means of single photograms obtained with white radiation. The photograms for both temperatures are reproduced in their paper, and there is a strong similarity between the two. However, for the latter temperature, the number of spots registered on the film was remarkably large for the grain size to be expected, and the authors made no mention of using a technique that would integrate a large enough area of the specimen to produce so many spots. The only other attempt to determine textures resulting from high temperature

Jan 1, 1945

By Joseph W. Leonard, T. S. Spicer

INTRODUCTION Reasons for Thermal Drying The continuing increase in the percentage of minus %-inch coal produced as a result of the increased use of mechanical mining methods has, over the years, tended to shift considerable portions of the work of producing saleable coal to the fine coal cleaning section of the preparation plant. Because a given weight of fine coal will contain substantially greater surface area than an equivalent weight of coarse coal, it follows that, when subjected to wet cleaning processes, the fines will absorb and retain consider- ably more moisture than coarser fractions. Increased moisture pickup in the finer sizes complicates fine coal cleaning since beneficiation may not be limited to the removal of ash and sulfur but often must be expanded to include the additional step of thermal drying to remove excessive moisture. Thus, water which provides the medium for cleaning fine coal is in itself detrimental and, like ash and sulfur, reduces coal quality. Removal of surface moisture by drying is done for one or more of the following 1 reasons: (1) To avoid freezing difficulties and to facilitate handling during shipment, storage and transfer to the points of use; (2) to maintain high pulverizer capacity; (3) to reduce heat loss due to evaporation of surface moisture from the coal in the burning process, thus increasing heating efficiency; (4) to improve the quality of coal used for special purposes, such as in the production of coke, briquettes, and chemicals; (5) to decrease transportation costs; and (6) to facilitate dry coal-cleaning processes. Because benefits to coal transportation and utilization are the most common reasons for thermal drying, the following sections will examine these areas in greater detail. Benefits to Transportation Initial benefits from drying are the reduction of shipping costs from the mine to the point of utilization since more coal can be concentrated into a given weight of product when worthless moisture is removed. Non- combustible~ such as water and mineral matter in railroad shipments of coal are billed the same as coal at $3.32 per ton, according to the recent average costs. Savings of 10 to 20 dollars from drying on the shipment cost of each 50 to 60 tons of coal contained in a typical railroad car is common. Savings on coal shipments from individual mines which result from coal drying can be expressed in terms of hundreds of thousands of dollars and more each year. For example, a reduction of shipping charges of only 5 percent on one million tons per year would mean a savings of 166,000

Jan 1, 1968

By Thomas E. Leontis

INTRODUCTION THE importance of magnesium alloys in the manufacture of aircraft engines has been realized for many years. A concentrated effort has been exerted in the laboratories of the Dow Chemical Co. to develop magnesium-base alloys with improved properties at elevated temperatures whereby greater advantage can be taken of the inherent lightness of these materials. In an earlier publication,1 attention was called to the superior tensile properties and resistance to creep of cerium-containing magnesium alloys at temperatures up to 700°F. More recently, additional data on magnesium-cerium alloys have been furnished by Murphy and Payne.2 The present paper deals with the mechanical properties of sand-cast magnesium alloys containing zinc, at temperatures up to 500°F. The study includes binary Mg-Zn† alloys containing up to 10 pct zinc and several ternary and some polynary alloys based on the Mg-1Zn,†Mg-3Zn, Mg-4.4Zn, Mg-6Zn, and Mg-10Zn binaries. The compositional variation in the tensile properties, hardness, and creep at room and elevated temperatures, and in the electrical conductivity at room temperature has been determined. The results of these tests show that many zinc-containing magnesium alloys exhibit resistance to creep at elevated temperatures significantly higher than that of present commercial magnesium alloys, but lower than that of alloys of the magnesium-cerium type. In addition, they have high tensile properties at room and elevated temperatures and high conductivity. This combination of mechanical properties and conductivity indicates that these alloys should be given serious consideration for commercial applications involving exposure to temperatures higher than those to which present commercial magnesium alloys can be taken safely. LITERATURE The properties of sand-cast magnesium alloys containing zinc as a principal alloying element have not been investigated very extensively, especially at elevated temperatures. The following remarks, which are confined to sand-cast alloys, will serve as a summary of the most important references on this phase of magnesium metallurgy. The first recorded determination of the tensile strength of binary Mg-Zn alloys as a function of zinc content was reported by Aitchison.3 Similar studies, including the measurement of elongation and hardness, have been performed by Gann and Winston,4 Dumas and Rockaert,5 Haughton and Prytherch,6 and by Spitaler, the last being reported by Beck.7 A slight superiority in the tensile strength of chillcast Mg + 8 Zn alloy over the sand-cast alloy was noted by Maybrey 8 That alloys of magnesium containing 5 to 12 pct zinc

Jan 1, 1948

By R. H. Fillnow, D. J. Mac

IT has been demonstrated that alloys in systems structurally analogous to steel undergo reactions during heat treatment similar to those of steel, and yet very little work has been done on such systems, particularly from the standpoint of isothermal transformation. The literature shows that most of the isothermal work has been done on copper-alu-minum alloys.'-3 One paper has been reported on a eutectoid copper-silicon alloy,' and one on iron-nitrogen alloys.' There are no published reports of previous investigations on the isothermal transformation of a eutectoid beryllium bronze. At least two papers have been reported on isothermal age-hardening phenomena in beryllium-copper alloys of lower beryllium content.5,6 No information on eutectoid transformations in this alloy is given in Rimbach's book, "Beryllium." ' This paper reports the results of an investigation on the isothermal transformation characteristics of a eutectoid beryllium bronze. Materials Used and Procedure The eutectoid beryllium bronze used in this investigation was centrifugally cast at the Ampco Metal Co., Inc.. Milwaukee. Wis. A master beryl-lium-copier alloy, purchased from the Brush Beryllium Co., was used to make the beryllium addition to the copper. The alloy was melted under a protective carbon cover and Centrifugally cast into a graphite mold preheated to 920°F. Some trouble with segregation of beryllium in the melt was encountered but was eliminated by violent stirring during melting and pouring. Since very thin .specimens were used for the various heat treatments, only one casting of the four prepared was necessary for the complete isothermal study, thus eliminating any discrepancies caused by a change in composition. The analysis of this casting was 94.035 pct copper and 5.965 pct beryllium. A slight trace of iron was found. The castings were sawed into specimens approximately 3/32 in. in thickness. The specimens were first given an "austenitizing" heat treatment at 788°C, well within the single phase beta region, in a vertical tube furnace. The specimens were then quenched individually into an adjacent molten salt bath and held there for a definite time, after which they were quenched into water at room temperature. Temperature was held to ± 2°C in the salt bath. No homogenizing treatment was given the specimens other than the soak at 788°C. Despite the fact that this was a cast alloy, no evidence of segregation or coring was found in the microstructure of any specimen, either as cast or as heat-treated. Upon completion of the heat treatment, the speci-mens were subjected to metallographic examination

Jan 1, 1951

Prof. Henry M. Howe, New York, N. Y. (communication to the Secretary*):—The results presented in Mr. Mathewson's paper are of very great interest. Perhaps the most interesting is that shown in Table I. and Fig. 1, in which the arsenic decreases in 10 min. from 0.22 to 0.07 per cent. This is such a large decrease that it is to be hoped that Mr. Mathewson will verify it by repeating his tests with a matte of similar composition. This is particularly to be desired, because the simultaneous removal of sulphur appears to be very small. All three blows further agree in showing that the removal of arsenic is in the very early part of the blow. The fact that the removal of arsenic then ceases abruptly cannot be explained completely by the fact that the arsenic has fallen so low as by its lowness to resist further removal, because in the first blow the arsenic becomes stationary at 0.06 per cent., whereas in the third blow it does not become stationary until it has fallen to 0.034 per cent. The abrupt ending of the removal of arsenic is more likely to find its explanation in the composition of the slag, and it is to be hoped that Mr. Mathewson will supplement these extremely valuable data with others in which the composition of the slag at the same time shall be given. The sudden rise of arsenic toward the end of the third blow I suppose must be referred to an error in sampling or analysis.

Jan 1, 1908

By L. F. Mondolfo

An aluminum-copper 4 pct Cu alloy aged at room temperature for times increasing up to 78,000 hr was annealed at 170°C and the hardness and electrolytic potential determined during retrogression and subsequent aging. It was found that there is a change of behavior with increasing time of aging at room temperature which indicates that, given sufficient time, retrogression disappears and the room-temperature aging tends to progress directly into the high-temperature aging. WHEN an age-hardenable alloy is aged at low temperature after proper quench, changes of properties and structure take place. If this material is then heated to a temperature higher than the previous one, but still well below the solution-treatment temperature, the properties and structure changes produced by the low-temperature aging disappear and the material apparently reverts to the as-quenched condition, ready to undergo aging from the start. This phenomenon is termed reversion or retrogression. First discovered by Cayler3l it has been extensively investigated, as shown by the number of publications listed in the bibliography. From all the information available the following facts emerge: 1) All aeg hardenable alloys can be retrogressed.9 13, 19) 24, 33, 41, 42, 44, 47, 53, 54, 61, 63, 64, 66, 73, 78 2) All the properties changes that take place during aging at low temperature can be retrogressed to a smaller or larger extent.4,5,7,12,19,32,49,50,57,58,60,67,75,76 67, 75, 76 3) Retrogression requires that the temperature be well above the preliminary aging temperature. If the difference between the two temperatures is small, Little or no retrogression takes place.7,20,32,33,41,49 57. 65 4) The larger the difference between the preliminary aging and the retrogression temperature, the faster and more complete is the retrogression.20, 33, 41, 48, 65, 67 5) Retrogression can be produced several times in the same alloy.23, 35,41,57,59 6) The amount of retrogression that can be obtained depends on the aging temperature. Alloys aged at the lower temperatures can be retrogressed the most. The higher the preliminary aging temperature the less retrogression can be produced.20,25,33,37,44,49,54,58 7) Appreciable retrogression after aging at elevated temperatures is possible only if the preliminary aging has lasted a short time. After a certain time of aging at high temerature retrogression does not take place any more,:5,6,9,10,11,21,40,58 8) During retrogression the Guinier-Preston zones redissolve and disappear. The other precipitate

Jan 1, 1960

By Earl S. Greiner, Eric R. Jette

ALTHOUGH the mechanical and chemical characteristics of certain iron-nickel-silicon alloys have been investigated,1 the available literature shows no results of a systematic investigation of the constitution of this system. This paper describes the results of an X-ray investigation of the constitution of the iron-rich iron-nickel-silicon alloys at 600°C. Data on the constitution of the included binary systems obtained in other investigations have been correlated with the structure of the ternary alloys. Jette and Foote2 have presented a tentative constitutional diagram of the iron-nickel system following X-ray studies on quenched specimens. This diagram shows that the alloys at 600°C. containing from zero to approximately 4 atomic per cent nickel consist of a body-centered cubic (alpha) phase, the alloys containing 4 to 24 atomic per cent nickel consist of body-centered cubic (alpha) and face- centered cubic (gamma) phases, and the alloys containing from 24 to 100 atomic per cent nickel consist of a face-centered cubic (gamma) phase. These investigators recognized that it was not possible to retain the gamma phase in equilibrium by quenching alloys containing less than approximately 25 atomic per cent nickel and that high-temperature X-ray methods were desirable to determine the gamma-phase solubility limit. In a later investigation of the iron-nickel alloys, Owen and Sulley3 determined the alpha-phase solid solubility limit to be 3.5 atomic per cent nickel at 600°C. High-temperature X-ray methods showed the solid solubility limit of the gamma phase to be 14 atomic per cent nickel at 600°C. Since the high-temperature X-ray method should reveal equilibrium conditions in these alloys better than the quench method of other investigators, the results of Owen and Sulley pertaining to the gamma-phase boundary are to be preferred. As the result of an X-ray investigation of quenched iron-silicon alloys, Greiner and Jette4 have shown these materials to consist of a body-centered cubic (alpha) phase containing from o to 26.4 atomic per cent silicon at 600°C. The alloys containing from 26.4 to approximately 50 atomic per cent silicon consist of two phases at 600°C.; namely, alpha and eta. The eta phase corresponds to the stoichiometrical formula FeSi (33.4 wt. per cent Si).* The literature pertaining to the constitution of the nickel-silicon alloys has been reviewed by Ackerman,5 who found disagreements in the results of various investigators on several parts of the system. Subsequent data on the constitution of the nickel-silicon alloys were reported by Osawa and Okamoto.6

Jan 1, 1943

By Fred S. Mulock

THE principal operating and producing properties covered by the Western Operations of the United States Smelting Refining and Mining Company are the U. S. and Lark mine in the Bingham district of Utah, the Bayard department in the Central mining district of New Mexico, the Midvale mill and smelter near Salt Lake City, the lead refinery of its subsidiary, U. S. S. Lead Refinery, Inc., at East Chicago, Ind., and the coal operations of its subsidiary, United States Fuel Company, at Hiawatha, Utah. Operations of lesser importance at this time are conducted either on company account or by lessees in the Centennial, Bullion Beck, and Eagle and Blue Bell mines in the Tintic district of Utah, the Hidden Treasure and Ophir mines in the Ophir district of Utah, and the White Knob mine in Custer County, Idaho. The Richmond-Eureka Mining Company, in which the Company owns a controlling interest, has leased its properties near Eureka, Nev., to the Eureka Corporation Limited. The Gold-road property at Goldroad, Ariz., has been shut down since 1942, and due to high costs of labor and supplies, consideration is now being given to removal of all surface and underground improvements. The mine and mill im¬provements at the Sunnyside property in Colorado, recently purchased by the Sunbank Corporation, a subsidiary of the Company, are now being dismantled.

Jan 1, 1948

By J. W. Craig, H. L. Walker

Industry has for many years recognized the dependence of certain mechanical and physical properties. as well as workability, upon grain size variations in brass. Although the dependence of properties upon grain size has been recognized there are not many instances where a planned program of testing has been conducted and where the only intentional variable has been grain size. In particular the literature is limited with respect to the effect of grain size on the endurance limit, though there are many industrial applications where the brasses are subjected to cycles of repetitive stresses. Literature A number of the physical and mechanical properties of a given brass sheet, in the annealed condition, will depend upon: (I) The ready-to-finish grain size before final rolling, (2) the percentage deformation by cold working, and (3) the time and temperature of annealing. The first and second variables affect the recrystallized grain size, and the third variable affects the coalesced grain size. Gibbsl has shown the effect of two different ready-to-finish grain sizes upon the tensile strength and hardness of deep drawing brass strip after a definite amount of cold rolling. The smaller the ready-to-finish grain size, the higher the tensile strength and hardness, but with lowered ductility, Gibbs also demonstrated, for a given time and temperature of anneal, that the tensile strength, hardness, and elastic limit are higher for the smaller ready-to-finish grain size, but the elongation is lowered. Townsend and Greena112 have reported data which show that cold working increases the tensile strength, hardness, and load carrying ability of deep drawing brass sheet under reversed stress. Greenall and Gohn3 have reported data which show that the smaller grain sizes have higher tensile strength and hardness properties, and the data also show that increased cold working increases the tensile strength and hardness properties of deep drawing brass sheet. Kommers4 has reported data for tests of brass of known ready-to-finish grain size, a specific amount of cold reduction, and annealed at different temperatures above and below the recrystallization temperature. Kommers' results indicate that annealing below the recrystallization temperature does not change the tensile strength and hardness properties, but the endurance limit may be increased from 22,000 to 28,000 psi. The increased endurance limit is explained as resulting from the reduction of internal stresses by a stress-relief anneal. Burghoff5 and associates have reported data on creep tests, over

Jan 1, 1949

By John R. Lewis

DURING the past few years there has been considerable interest in the sizing and the preparation of the iron ore fed into blast furnaces. Furnacemen know that proper sizing of ore tends to increase the efficiency of the furnace. It has been shown by Joseph1 and his associates that there is a direct relationship between the porosity of an ore particle and the time required for its reduction in the blast furnace. This relationship may be stated as follows: All other factors remaining constant, the time for reduction of a given sample of ore is inversely proportional to its porosity. As a consequence, large pieces of very porous ore, say 3 or 4 in. in cross section, will be completely reduced by the time they reach the hot zone just above the tuyeres, while large pieces of dense, nonporous ore may reach the hot zone with their centers unreduced. This means that for the latter complete reduction will be accomplished by the so-called "direct method;" i.e., where carbon reacts directly with the ore. Some recent work by Philbrook2 seems to contradict this rule. He found that of two unlike ores he studied, the one with the lower porosity reduced more readily. He explained his results as "possibly due to an apparently greater tendency of the `A' ore (lower porosity) to crack during preliminary dehydration and during reduction." This brings his results in line with the rule stated above. It is not the author's intention to enter into a discussion of the merits of "direct" versus "indirect" reduction. It is enough to say that, in general, indirect reduction is desirable. For the greatest efficiency, Gruner's theorem3 requires that all reduction in the blast furnace be indirect. Joseph seems to believe this also, because in his recent article on Some Comparisons between Iron Ore, Sinter and Nodules as Blast Furnace Feed' he concludes that: "In general, the carbon in blast-furnace coke is used most efficiently when the largest amount of the carbon charged reaches the tuyeres." However, P. V. Martin,' in an excellent paper, has shown that some direct reduction may actually increase the efficiency of the furnace; that is, increase its rate of production while maintaining maximum fuel economy. For nonporous ores there is more opportunity to have an excess of direct reduction unless the factors that make for indirect reduction are favored; for instance; the proper sizing of the ore particles. Another factor that has an important bearing on the reduction rate, as it is affected by particle size, is the flow of heat into the particle. The ore particle

Jan 1, 1947

By Eric R. Jette, Earl S. Greiner

Although the mechanical and chemical characteristics of certain iron-nickel-silicon alloys have been investigated,1 the available literature shows no results of a systematic investigation of the constitution of this system. 'This paper describes the results of an X-ray investigation of the constitution of the iron-rich iron-nickel-silicon alloys at 600°C. Data 011 the constitution of the included binary systems obtained in other investigations have been correlated with the structure of the ternary alloys. Jette and Foote2 have presented a tentative constitutional diagram of the iron-nickel system. following X-ray studies on quenched specimens. This diagram shows that the alloys at 600°C. containing from zero to approximately 4 atomic per cent nickel consist of a body-centered cubic (alpha) phase, the alloys containing 4 to 24 atomic per cent nickel consist of body-centered cubic (alpha) and face-centered cubic (gamma) phases, and the alloys containing from 24 to Ioo atomic per cent nickel consist of a face-centered cubic (gamma) phase. These investigators recognized that it was not possible to retain the gamma phase in equilibrium by quenching alloys containing less than approximately 25 atomic per cent nickel and that high-temperature X-ray methods were desirable to determine the gamma-phase solubility limit. In a later investigation of the iron-nickel alloys, Owen and Sulley3 determined the alpha-phase solid solubility limit to be 3.5 atomic per cent nickel at 600°C. High-temperature X-ray methods showed the solid solubility limit of the gamma phase to be 14 atomic per cent nickel at 600°C. Since the high-temperature X-ray method should reveal equilibrium conditions in these alloys better than the quench method of other investigators, the results of Owen and Sulley pertaining to the gamma-phase boundary are to be preferred. As the result of an X-ray investigation of quenched iron-silicon alloys, Greiner and Jette4 have shown these materials to consist of a body-centered cubic (alpha) phase containing from o to 26.4 atomic per cent silicon at 600°C. The alloys containing from 26.4 to approximately 50 atomic per cent silicon consist of two phases at 600°C.; namely, alpha and eta. The eta phase corresponds to the stoichiometrical formula FeSi (33.4 wt per cent Si)." The literature pertaining to the constitution of the nickel-silicon alloys has been reviewed by Ackerman,' who found disagreements in the results of various investigators on several parts of the system. Subsequent data on the constitution of the nickel-silicon alloys were reported by oSawa and okamoto.6

Jan 1, 1943

By Earl S. Greiner, Eric R. Jette

Although the mechanical and chemical characteristics of certain iron-nickel-silicon alloys have been investigated,1 the available literature shows no results of a systematic investigation of the constitution of this system. 'This paper describes the results of an X-ray investigation of the constitution of the iron-rich iron-nickel-silicon alloys at 600°C. Data 011 the constitution of the included binary systems obtained in other investigations have been correlated with the structure of the ternary alloys. Jette and Foote2 have presented a tentative constitutional diagram of the iron-nickel system. following X-ray studies on quenched specimens. This diagram shows that the alloys at 600°C. containing from zero to approximately 4 atomic per cent nickel consist of a body-centered cubic (alpha) phase, the alloys containing 4 to 24 atomic per cent nickel consist of body-centered cubic (alpha) and face-centered cubic (gamma) phases, and the alloys containing from 24 to Ioo atomic per cent nickel consist of a face-centered cubic (gamma) phase. These investigators recognized that it was not possible to retain the gamma phase in equilibrium by quenching alloys containing less than approximately 25 atomic per cent nickel and that high-temperature X-ray methods were desirable to determine the gamma-phase solubility limit. In a later investigation of the iron-nickel alloys, Owen and Sulley3 determined the alpha-phase solid solubility limit to be 3.5 atomic per cent nickel at 600°C. High-temperature X-ray methods showed the solid solubility limit of the gamma phase to be 14 atomic per cent nickel at 600°C. Since the high-temperature X-ray method should reveal equilibrium conditions in these alloys better than the quench method of other investigators, the results of Owen and Sulley pertaining to the gamma-phase boundary are to be preferred. As the result of an X-ray investigation of quenched iron-silicon alloys, Greiner and Jette4 have shown these materials to consist of a body-centered cubic (alpha) phase containing from o to 26.4 atomic per cent silicon at 600°C. The alloys containing from 26.4 to approximately 50 atomic per cent silicon consist of two phases at 600°C.; namely, alpha and eta. The eta phase corresponds to the stoichiometrical formula FeSi (33.4 wt per cent Si)." The literature pertaining to the constitution of the nickel-silicon alloys has been reviewed by Ackerman,' who found disagreements in the results of various investigators on several parts of the system. Subsequent data on the constitution of the nickel-silicon alloys were reported by oSawa and okamoto.6

Jan 1, 1943

By Bruce A. Kennedy

The 1960's were an apparent turning point in the technological and social attitudes and awareness of the mining industry. From the late 19th century through to the early 20th century, one has always been presented with the picture of the rough and ready leaders of the mining industry who screamed for production and damned anything that got in the way of it. This attitude led to a certain alienation of the mining industry in the eyes of the general public. They saw an industry which was archaic in many of its practices and often heartless in its attitudes towards mankind. However, a gradual change spread through the industry and cracks began to appear in the hard facades of the mining companies. Resistance to change had almost become a standard operating procedure for many and consequently changes in technology had been slow in coming. The late 1950's and the 1960's saw a new awareness come into existence. As the mining company managements changed, there developed a realization that considerable efforts had to be made to bring the technology and social standing of the industry out of the dark ages and into the modern world. New advances were made in both metallurgical and mining technology. The 20th century technology of computers was accepted and became a standard tool of the industry.

Jan 1, 1971

By C. H. Li, J. Washburn, E. R. Parker

Yield stress in single crystals of zinc was shown to be dependent on prior annealing temperature and rate of cooling after annealing. Rate of strain hardening beyond the yield was not sensitive to annealing procedure. A tentative mechanism for the effect was discussed. COMPARATIVE mechanical tests of metal single crystals generally show a large scatter of results. Many factors may contribute to this variation. The present investigation was undertaken to evaluate the influence of two factors not ordinarily considered of major importance—annealing temperature and cooling rate after annealing. Since plastic properties of crystals are thought to depend on the presence of lattice imperfections, it follows that a variation in properties should result from differences in the distribution and density of these imperfections. Furthermore, in the light of current theories of interaction between edge dislocations and lattice vacancies,' it seems possible that annealing temperature and subsequent rate of cooling might play a part in this distribution. Analysis of the effect of these variables on plastic properties may lead to a better understanding of the annealed state. Single crystals of zinc which have been strained in simple shear undergo complete recovery of mechanical properties upon subsequent annealing. This behavior is useful because a single specimen can be used repeatedly, thus eliminating the uncontrollable variables introduced by the use of many crystals. The test section of the crystals used for these experiments was a cylinder 1/8 in. thick with a cross-sectional area of about 1/3 sq in. The specimens were acid-machined from spherical single crystals 1 in. in diameter in such a way that the slip plane (0001) was at right angles to the axis of the cylinder. In testing, a shear stress was applied along one of the slip directions, [2110] in the (0001) plane.' All crystals, unless otherwise noted, were grown in a helium atmosphere from molten 99.99 pct pure Horse Head Special Zinc. Fig. 1 is a family of curves obtained from one crystal. Each curve was obtained by deforming the crystal to 10 pct strain at a rate of 3 pct per min, following an anneal of 1 hr at 260°C. The strain direction was reversed every other time so that no progressive change in shape of the specimen took place during the series of tests. Since the stress-strain curve was reproducible within a fairly narrow range under the same conditions of annealing, it was then possible to determine the effect of changes in annealing conditions. A crystal was tested repeatedly as previously described but the annealing temperature and rate of cooling preceding each test were varied (Fig. 2). Two cooling rates were used, approximately 30°C per min and 3°C per min. Annealing was conducted at three temperatures, 200°, 300°, and 400°C. For a given annealing time and rate of cooling the room temperature flow stress was higher the higher the annealing temperature. The increase in flow stress was small as the annealing temperature was increased from 200° to 300°C but rose rapidly when the annealing temperature was raised from 300" to 400°C. Faster cooling from the high temperature produced an even greater strengthening of the crystal. The curves were obtained in the order indicated by the numbers. The stress level associated with a certain annealing treatment was, within the limits of scatter, always the same regardless of the

Jan 1, 1954

By W. I. Duvall

A brief review of the resonant frequency and ultrasonic pulse methods for obtaining elastic constants of rock samples shows that the equations for an iso-tropic elastic solid commonly used to calculate Young's modulus, modulus of rigidity and Poisson's ratio can result in appreciable error if the rock is even slightly anisotropic. Consideration of the equations that relate bar velocities and free medium velocities to elastic constants for orthotropic, transversely isotropic and isotropic solids shows that a combination of the two methods can be used to determine average elastic constants for a single sample of rock. The determination of elastic constants in different directions requires a large number of tests on oriented samples. The use of both the resonant frequency and ultrasonic pulse methods is recommended so that the determination of both Young's modulus and modulus of rigidity is independent of the determination of Poisson's ratio. The dynamic elastic constants of rock can be determined in the laboratory from measurements on small samples which may be in the form of right circular cylinders (diamond drill core). Either the resonant frequency6 or ultrasonic pulse method1 can be used to determine the longitudinal and shear velocities in the same specimen. The resonant frequency method provides a measure of the longitudinal bar velocity, V,, and the torsional bar velocity Vt; whereas the ultrasonic pulse method provides a measure of the free medium longitudinal velocity, Vp, and the free medium shear velocity, V, . The elastic constants (Young's modulus E, modulus of rigidity G, and Poisson's ratio v) are calculated from the density of the specimen, p, and one of the pairs of velocities by means of equations from isotropic elastic theory. For the resonant frequency method the equations are: It should be noted that Eq. 5 is derived from Eq. 4 and 6 and the relation between the elastic constants for an isotropic solid as given by the first part of Eq. 3. The in situ determination of dynamic elastic constants is accomplished by generating a complex seismic pulse in the rock and measuring the arrival times for the longitudinal and shear phases of the pulse at two distant points.5 From these travel times and the distance of the travel path both Vp and Vs are determined. The density of the rock is determined from samples in the laboratory, and Eq. 4 to 6 are used to calculate the elastic constants. These three methods involve the assumption of isotropy and perfect elasticity, and require the use of the relation v = (E/2G) - 1, which holds only if the elastic constants are the same in at least two directions. The calculation of v by means of Eq. 3 introduces considerable error, as a 1% error in V, and V, results in a 20% error in v. If frequencies for samples with a length-to-diameter ratio greater than four and a length greater than 8 in. are measured carefully, the experimental error can be kept to 1%. However, it is not unreasonable to expect that the variation in Vb and Vt with direction may exceed 1%. Thus, for even a small percentage of anisotropy the use of Eq. 3 can result in considerable error in v. The calculation of v by Eq. 5 also involves some uncertainty as a 1% error in Vs and Vp can result in a 6% error in v. By means of the pulse method both

Jan 1, 1965

By W. D. Robertson, A. S. Tetelman

The technique of decorating dislocations was employed to investigate deformation and fracture resulting from Precipitation of hydrogen in Fe-3 pet Si single crystals. It is shown that cracks are produced on (100) planes inside crystals, as a consequence of the precipitation of hydrogen gas, either when crystals are quenched from a hydrogen atmosphere at elevated temperatures or cathodically charged with hydrogen at room temperature. Plastic deformation in the vicinity of cracks, observed as arrays of decorated dislocations, is in conformity with the calculated stress distribution about a crack containing an internal pressure, and the observations provide information permitting a detailed analysis of the mechanics of crack growth. The fracture characteristics of crystals containing internal cracks were evaluated at 25o and -196°C and the results are related to the mechanism of hydrogen embrittlement in terms of the growth of preexisting cracks. HYDROGEN in bee iron or steel produces two characteristic changes in mechanical properties: I), a decrease in ductility (macroscopic strain at fracture) that depends on temperature and strain rate, and 2), spontaneous fracture under static load that depends on time and apparent stress. Resolution of these phenomena into the microscopic processes that combine to produce the macroscopic effects is especially difficult in the Fe-H system in which the active component cannot be directly observed and only maintained in equilibrium with great difficulty in the temperature and pressure range in which embrittlement phenomena appear. As a result of these complications, verification of the numerous hypotheses'-5 that have been proposed to explain the microscopic mechanism of embrittlement depends on self-consistency with measured changes in macroscopic properties that are averaged over the volume of a specimen. It is obviously important to obtain a more direct evaluation of the microscopic processes that combine to produce embrittlement. Accordingly, the present investigation was designed to identify and observe, as directly as possible, the microscopic effects of introducting hydrogen into a bee crystal. It was concluded from a previous investigation6 of X-ray line broadening, produced by introducing hydrogen into pure iron at room temperature, that the only effect that could be associated with the introduction of hydrogen was plastic deformation; in particular, dilation of the lattice was not observed, within ± 0.01 pet, and no evidence was found that could be interpreted to support the idea7'* that hydrogen occupies tetrahedral interstitial sites in the iron lattice. The absence of lattice dilation is consistent with the extremely small solubility of hydrogen in bee iron9,10 (0.015 at. pet at 900oC and 1 atm pressure), and the evidence of plastic deformation is consistent with the fact that hydrogen, introduced by cathodic charging, eliminates the carbon yield point.11-13 Following this investigation, the immediate problem was to devise a method by which plastic deformation could be observed directly. The technique employed by Hibbard and Dunn14 to observe the movement of dislocations during bending and subsequent polygonization of Fe-3 pet Si single crystals was adopted and modified for the present purpose to include the observation of dislocation arrays in the volume of the crystal, and their association with the fracture process. EXPERIMENTAL PROCEDURE Single crystals of a high purity Fe-3 pet Si alloy, containing 0.007 pet C, were grown in vacuum by

Jan 1, 1962

By Walter Stern

THE self-potential or spontaneous polarization method is one of the oldest in the field of electrical exploration. When applied in prospecting for ore bodies, it is one of the most rapid and inexpensive means of locating indications of ore bodies at shallow depth. Usually, the procedure is to survey the equipotential lines of the electrical field that is generated by the electrochemical activity of the ore near the ground-water level, and to localize the so-called negative centers or points of greatest negative anomaly. Another field procedure involves the measurement of potential differences along potential profiles, generally laid out at right angles to the assumed strike. Again, in such survey, the basis for establishing the presence of ore is the location of negative potential anomalies. The earlier writers on the subject, notably Schlumberger1 and R. G. Wells,2 did much to clarify the fundamental electrochemical phenomena involved. Interpretation of the field data, however, remained largely qualitative. In 1925, A. Petrovsky3 analyzed the relation between the shape of the potential anomaly curve and size and depth of an ore body by assuming the subsurface body to be a polarized sphere.4 Along similar lines of approach, Edge and Laby5 considered the ore body a dipping sheet with limited extent in the direction of strike, while Poldini6 based the theory on the assumption of a dipping bar. The following study endeavors to enlarge [ ] FIG. I.-ORE BODY CONSIDERED AS DIPOLE upon these earlier investigations and attempts, on the basis of the potential distribution of a polarized bar, to indicate certain characteristics of the anomaly curve that make possible the determination of depth, size and dip of a subsurface body. THE SPONTANEOUS POLARIZATION FIELD SET UP BY AN ORE BODY If a sulphide ore body is subjected to oxidation varying in degree in its upper and lower parts according to the difference in the concentration of oxygen within the surrounding medium, an electrical potential field is set up. The form and distribution of this field will be investigated herein with special reference to its components on the earth's surface. Under the simplifying assumption that the ore body may be considered as a dipole with the point sources QI and Q2 situated at its upper and lower ends (Fig. I), the potential of the spontaneous polarization at point P is given by the following equation:

Jan 1, 1944

By S. L. Couling, D. J-P. Adenis

i2) twinning in poly crystalline magnesium does not usually occur homogeneously but is concentrated in localized regions or bands inclined at about 45 deg to the stress axis. These bands of twinning are in many ways similar to the Luders bands seen in mild steel alzd Al-Mg alloys. Within a hand the percentage of the volume twinned may approach 100 with no twinning outside the band. Bands are not produced in specimens of grain size a3 x 10-= in. or in samples deformed at temperatures 300°F. Annealing of heavily twinned regions leads to re crystallization textures markedly different from those found in the starting material. The exact preferred orientation appears to depend on the starting grain size, the amount of compres-sive strain and the manner in which it is introduced. MAGNESIUM, with its hexagonal crystal structure, deforms plastically at room temperature by a variety of deformation mechanisms, one of the most important of which is (1012) twinning. In single crystals such twinning occurs on compression parallel to the basal plane or tension perpendicular to it. In wrought polycrystalline magnesium, such as rolled sheet, the preferred orientation is such that almost all the grains have their basal planes nearly parallel to the sheet surface. Therefore, if sheet material is deformed by cold rolling or by tension in the plane of the sheet, deformation of the grains by (1012) twinning is not favored. On the other hand, twins form readily on compression parallel to the plane of the sheet as in a compression test, on the compression side of a bent sample, or at the outer rim of a drawn cup. The first part of this paper deals with the morphology of (1012) twinning in polycrystalline magnesium. Some aspects of this subject were covered by Barrett and ~aller.' Of direct bearing on the work to be reported here are the comments of Jetter' in discussion to Ref. 1. He shows that Mg + 1.5 pct Mn alloy sheet when bent about a transverse axis develops a pattern of transverse bands on the surface of compression. A longitudinal section through the sheet shows that the bands are wedge-shaped and inclined to the rolling direction. The bands were identified as "outcrops of regions in which deformation is localized as the result of the reorientation brought about by (1012) twinning". The second part of the paper treats the recrys-tallization texture of the specimens twinned by compression. Magnesium deformed and then annealed generally recrystallizes with no change in orientation.1'3'4 This statement is true provided that the amount of (1012) twinning occurring during deformation is small. In an isolated observation, Anse15 has shown that, when deformation produces much (1072) twinning, annealing causes new maxima to appear in the pole figure. The second part of the paper elaborates on this point. I) MATERIALS AND PROCEDURES All of the experimental work to be reported was done using the commercial sheet and plate alloy AZ31B (nominal composition: 3 pct Al, 1 pct Zn, 0.4 pct Mn, balance magnesium). This alloy is available commercially in two tempers, -0 (fully annealed) and -H24 (partially annealed), and specimens of both tempers were used in various experiments. The average grain. diameter (AGD) for -0 temper 0.125-in. sheet is about 0.5 x 10- in.; where material of larger grain size was desired, anneals at elevated temperature were used to grow the grains. compression tests were made on a screw-driven "hard" machine. The specimens were clamped in a

Jan 1, 1964