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Jan 1, 1969

By Charles J. Potter

There are many sources of energy available for consumption. Some available are solar, tide and wind. However, in terms of relatively large usage, only four principal sources are used for primary energy today. They are coal, oil, natural gas and water power. Such additional items as wood and nuclear energy, although supplying quantities of energy today, do not in the aggregate amount to any real significant quantity, but nuclear energy must be considered for future use. In addition, such a thing as gas from distillation of coal and oil is not considered primary energy. The principal markets for primary energy are the electric power utilities, space heating, industrial uses and transportation. The electric utility use of energy is primarily from coal, followed by natural gas and water power. Space heating is primarily a gas market, followed by oil and then coal. Space heating by electricity is only considered in the generation of electric power. Transportation's principal source of energy is oil. Coal has practically no market left in this field.

Jan 4, 1962

By Per Kofstad, Hallstein Kjöllesdal

The oxidation behavior of niobium (columbium) has been studied in the temperature range 500° to 1200°C and at oxygen pressures of 760,100, 10, 1, and 0.1 mm of Hg. The work comprises kinetic studies of the oxidation as well as structural investigations of the oxidized specimens by means of X-ray diffraction, electron diffraclion, electron microscopy, and metal1ographic techniques. The oxidation reaction has a highly irregular temperature dependence and is unusually sensitive to changes in the oxygen pressure. The complex oxidation behavior is suggested to be due to formation of different Nb2O5 modifications in different temperature regions. During oxidation oxygen is also dissolved in the metal. Formation of oxide whiskers take place on the oxide surface at temperatures above approximately 800°C. VARIOUS aspects of the oxidation of niobium have been studied.l-12 The investigations show that niobium has a complex oxidation behavior, and the oxidation

Jan 1, 1962

By J. W. Rutter, K. T. Aust

The motion of individual grain boundaries under a constant driving force was investi,qated for zone-refined lead, with and without solute tin additions. The rate of boundary migration was found to depend strongly on tin content and on the orientation relationship between the adjacent grains. The results are compared with the theory of impurity-controlled grain boundary miqration developed by Lucke and Detert. Evidence was found that grain boundaries separating grains which have the Kronberg-U&apos;ilson orientation relationships of 38 and 22 deg about <Ill> and 28 deg about <100>, correspond to boundaries of high mobility. The results are discussed in relation to the formation of annealing textures in metals and the structure of high-angle boundaries. It is generally known that small amounts of impurities in solid solution greatly influence the re-crystallization behavior of metals. For example, the addition of 0.005 at. pct of tellurium to copper,&apos; or 0.005 at. pct of silver to lead,2or 0.01 at. pct of manganese or nickel to aluminum3 greatly decreases the rate of recrystallization of these metals. However, this effect may be the combined result of a decrease in the rates of both nucleation and growth; recrystallization experiments do not separate these two factors. Bolling and winegard4 determined the effects of small quantities of tin, silver, and gold on grain growth in polycrystalline zone-refined lead.

Jan 1, 1960

By Orrin P. Peterson

The decision of the Supreme Court -of the United States not to review the findings of the lower courts closes an interesting chapter in the mining litigation that has arisen as a result of the extralateral feature of the mining law. The time seems opportune to record some of the important geological features, and also some of the legal features, of the controversy, in the hope that these will be permanently accessible to members of the mining profession. After many rumors of litigation, the Utah Consolidated Mining Co. sued its neighbor for the ore that had been, it was alleged, wrongfully extracted from its so-called Yampa limestone lode. This ore lay beneath Utah-Apex surface and was claimed by virtue of the extralatera1 rights conferred on the Utah Consolidated Co. through the ownership of certain specific mining claims, one of the principal claims being the Yampa. Previous to bringing suit, the Utah Consolidated Co. had strengthened its position by purchasing the Old Yampa mine and by making an agreement with the Utah Metal & Tunnel Co., which gave it clearer title to the outcrop of the Highland Boy limestone. Access to the workings of the Utah-Apex Co. was secured and reciprocal privileges gave Utah-Apex representatives the right to enter the properties of the Utah Consolidated Co. This resulted in the Utah-Apex immediately bringing countersuit for ore alleged to have been wrongfully extracted from under its surface in the Leadville country, see Fig. 4. Six cases came up for consideration: five related to the original suit and the countersuit, and one related to the Dana extralateral claims of the Utah-Apex Co. Well-known attorneys, geologists, and mining engineers were engaged by both sides, and thousands of feet of development work were done to prove or disprove ideas that would sustain the contentions of the opposing sides. Models of wood, wire, and glass were constructed to present clearly to the court the actual physical relations. These models were also of great value to the attorneys and witnesses in clarifying hazy impres-

Jan 1, 1924

By E. P. Polushkin

This work has for its purpose the establishment of a new method for determining the structural composition of alloys. The area occupied by a constituent on a few representative photomicrographs of the alloy is measured, by a planimeter, especially designed for metallographic work, and the volume and proportional weight of the constituent calculated. Experiments have shown that the results are accurate enough to justify the application of the method to many problems in metallographic research instead of chemical analysis. The advantage of the method is the possibility of determining the amount of the constituents without separating them from the alloy; their composition may also be determined if the ultimate chemical analysis of the alloy is known. Suppose Fig. 1 represents a part of a photomicrograph on which the total area of the black figures is to be found. By a system of parallel lines drawn short equal distances apart all figures may be divided into trapezoids. As the area of a trapezoid is equal to its median multiplied by its altitude, the relation between the total areas of the black and the white figures comprised within each strip is equal to the relation between the sums of medians for these figures respectively. This is also true for the whole area of the photomicrograph. Therefore, to determine the total areas of the black and white figures we must first find the proportion between the sums of the medians and then divide the area of the whole photomicrograph in the same proportion.

Jan 1, 1925

By Eduardo Martinez Baca

Although Mexico has always been justly considered by the whole world essentially a mining country, this reputation is due principally to the richness of the deposits which have been worked. In reality, the majority of the States have been little

Jan 1, 1902

By D. G. F. Hedley, D. F. Coates, K. Barron

INTRODUCTION Preceding papers presented in this symposium have considered the influence of various parameters, such as geologic structure, groundwater, etc., on the stability of rock slopes and have given some analyses and guide lines for slope design. To carry out such analyses it is necessary to put numbers to these parameters; where possible, this is best done on the basis of in- situ observation and measurement. Since none of the design analyses can be considered exact and since conditions vary during excavation, it is also desirable to monitor the behaviour of the slopes as the excavation proceeds. In this manner a feedback of information on the actual excavation conditions can allow a continuous reassessment of the design parameters to be made and can give early warning of incipient failures. The purpose of instrumenting rock slopes is thus to provide information which fits into one of two categories: (a) To give basic data to assist on-site assessment and design of the rock excavation. (b) To provide data for the control and assessment of safety during excavation. The purpose of this paper is to review briefly some of the instruments and measuring techniques available for gathering this data and to indicate where such data may prove useful. This is not a comprehensive review of all available instrumentation but, rather, is a survey of some of the instruments and techniques with which the authors have had some experience and which have proven useful. STRUCTURAL ASSESSMENT Whilst most structural assessment of a site is done on the basis of geologic mapping and core examination, there exists some instrumentation which can, in particular circumstances, assist in this assessment. Seismic instruments can be used to determine the geometry of formations and to give an indication of the relative competency of rocks. These instruments operate using seismic reflection or refraction techniques and, although mainly confined to shallow sub-surface exploration, can be useful in distinguishing between soil/ bedrock contacts and, in some cases, the extent of weathered surface rock.

Jan 1, 1971

By J. Kent Smith

The object of this investigation was to ascertain the effect of varying percentages of beryllium upon pure copper and the properties of the resultant alloys in their softest condition, the effect of heat hardening on them, and the extents to which these properties could be augmented by different combinations of heat hardening and cold rolling. The data compiled in this paper represent partial results of continuing work done by the writer during the years 1930 and 1931, which was a continuation of the unpublished ground work incepted in the laboratory of the Beryllium Corporation of America by H. B. Pulsifer in the year 1926. A short bibliography on beryllium alloys is appended to this paper. It has, of course, long been known that copper subjected to cold work is hardened and strengthened to a considerable extent; furthermore it had been qualitatively noted in previous experiments that copper-beryllium alloys seemed to take on hardness and strength as the result of cold work at a greater rate even than does plain copper. It was decided therefore to endeavor quantitatively to determine such rate of increase, as also the relative increases by combinations of cold working and heat hardening. The results are summarized in Tables 3, 4 and 5. A preliminary series of experiments had indicated that by an exposure to the heat of 575" F. for 2 1/2 hr. age-hardening of a 2.50 per cent beryllium-copper alloy took place. Slab ingots of nine different beryllium-copper alloys were prepared under identical conditions by means of the addition of a previously prepared 12.5 per cent beryllium-copper alloy to well melted and deoxidized pure copper. The ingots were then reduced by hot rolling to 12 gage (about 0.080 in.). These strips were heated to 1450" F. and quenched in cold water, and thus brought to their softest condition. (See Table 1.) Strips were next "precipitation-hardened" by reheating to a definite temperature. Similar strips to those itemized in Table 1 (which had been quenched from 1450" F.) were reheated for varying periods of time at 575" F. The hardness figures show that a metastable condition, of which the range of stability is dependent entirely upon time at the given temperature, begins to be noted in copper samples containing as little as 0.85 per cent beryllium. It is extremely noticeable in samples containing

Jan 1, 1932

By E. J. Horwood

The varying physical character and large extent of the Broken Hill lode necesarily involve the employment of a variety of underground methods. The lode had its origin in an extensive fault plane traversing metamorphosed schists conformably, as a rule, with their beds of stratification. The underground waters carrying minerals in solution deposited their contents in the original cavities formed by the faulting action, and in the enlargements of these cavities due to dynamic forces brought to bear on the rocks, more especially on the hanging-wall side of the fault. This deposition was supplemented by metasomatic replacement of a portion of the original rock contents by the argentiferous sulphides of lead and zinc which form the staple products of the district. Although the orebody is practically continuous throughout the mines, its width varies greatly, ranging from a few feet to about 350 ft. The widest portions occur in conjunction with huge folds in the inclosing country rock, almost exclusively on the hanging-wall side. The ore in these folds pitches to the south in the southern half of the field, and to the north in the northern half; there are, however, undulations in these ore channels evidently due to compression of the rocks in the direction of the channels. In the earlier days, before the orebodies had been opened up, vertical cross-sections across these bulges in the hanging wall gave the lode the appearance of the "saddle formation," so well exemplified at Bendigo in Victoria; but subsequent development of the ore channels has long since proved that the formations in the two districts are entirely different. The depth reached by the zone of complete oxidation of the sulphides varies from about 259 to 550 ft, from the original outcrop, while partial oxidation extends in places below the 1,000-ft. level. The result of oxidizing influences has been the production of ore of every grade of cohesive-ness, from that of dry sand to that of hard compact rock. The methods of mining followed in this field, and even in individual mines, are varied in accordance with the character of the ore. The general practice of the field is to sink vertical shafts, generally on the foot-

Jan 1, 1916

By Robert T. Hill

The successful completion, January 10,1901, by Capt. A. F. Lucas, of a well, near Beaumont, Texas, whereby an enormous flow, estimated at &apos;75,000 barrels a day, was obtained, opened a new oil-field in the United States, kindled a frenzy of exploitation and speculation, revolutionized the fuel industry of a large region, and brought gain to thousands of people. Even to-day, it is impossible to cast up the present results or to prognosticate the future influence of this event. It has caused the revival of attention in other localities where oil had been suspected, and exploration for oil throughout the Texas region. It has attracted notice to the mineral resources of the Texas region, and created an interest in the geological conditions of that great State. This State, which has increased in population and wealth, as recorded by every succeeding census, with leaps and bounds such as are exhibited by no other part of the Union, now stands fifth in population and first in productive wealth per capita. Its fields, pastures, forests and mines teem with raw material. The whole economic evolution of the State has gravitated toward a focal point where these products were available for the coming of the kiln, the machine and the factory. The only drawback to the prosperity of the State was the lack of an economic fuel, inferior coal costing an average of $5.00 per ton at the time of the Beaumont discovery. This

Jan 1, 1903

By William J., Coulter

IN the early days of Colorado mining, between 1880 and 1900, when Leadville, Kokomo, and Robinson were boom mining camps, the entire area around Climax for a matter of fifteen miles was overrun with prospectors, so the mineralized outcrop at Climax was not unknown. The principal interest in minerals during this period was in gold, silver, and lead, and since the Climax outcrop showed none of these it drew little attention. Geology played an important part in bringing prospectors to the very edge of the Climax deposit. The Mosquito fault, which crosses near the base of Bartlett Mountain, continues as an important geological structure, at least as far as Leadville some twelve miles distant, and at the base of Bartlett Mountain the vertical throw on the fault is estimated to be between 2000 and 5000 ft. The sedimentary beds known to the Leadville district are all present on Bartlett Mountain to the north of the Mosquito fault, which cuts them off abruptly, and exposes the Pre-Cambrian rocks that underlaid them, so the prospectors, who were searching for gold, silver, and lead in the sediments

Jan 1, 1946

By J. M. Flaitz, A. S. Parks

OF the various methods of sampling gas-condensate wells, a method that secures a continuous representative sample of the well stream is desirable. Such a method, consisting of a sampling tube introduced into the well tubing, has proved satisfactory. The method is sufficiently accurate for operating and engineering problems A portable testing apparatus can be used with the sampling tube to obtain data useful in studying the economic and technical aspects of the development and operation of gas-condensate properties. Introduction The recent discovery and development of gas reserves that contain hydrocarbons that condense with reduction of temperature or Pressure, or both, to form a product known as condensate, has brought many new problems to the oil and gas industries. With further discovery of deep, high-pressure fields it is presumable that many more gas fields of this type will be added to the steadily increasing number. Such gas reserves are found either associated with oil as a gas cap or in separate formations. There seems to be no positive correlation between the physical or geological nature of the reservoir, and the chemical composition or phase characteristics of its contents. Knowledge of the chemical make-up and phase behavior of gas-condensate reserves is needed to cope with many problems. A knowledge of the chemical composition and phase characteristics of the reservoir material is necessary to properly design a gasoline or recycling plant, to estimate natural gas and condensate reserves, to enable the operator to study the economic and technical aspects of various methods of operation and development, and to carry Out the plan of operating subsurface and surface lease equipment. This information is often useful in questions of mineral ownership, proration, legal position, and taxation. It is the purpose of this paper to discuss methods used by the writers to determine the chemica1 composition and phase characteristics of the fluids produced from a condensate well. The scope of the paper includes a discussion and description of the method of sampling, the results of tests on the accuracy of the sampling method, a description of a portable testing apparatus used to examine the phase characteristics, typical results of tests on wells from several condensate fields, and some of the applications of these data to production problems. References to previous work on this subject are cited at the end of the paper. The Problem At reservoir conditions of temperature and pressure, the fluids produced from a condensate well exist in a homogeneous vaporous condition. The consequent reduction of temperature and pressure that occurs as this gas enters and flows up the well tube results in condensation of some of the hydrocarbon material to form a liquid. The relative amount of liquid condensed at any point in the flowing system

Jan 1, 1942

By J. M. Flaitz, A. S. Parks

OF the various methods of sampling gas-condensate wells, a method that secures a continuous representative sample of the well stream is desirable. Such a method, consisting of a sampling tube introduced into the well tubing, has proved satisfactory. The method is sufficiently accurate for operating and engineering problems A portable testing apparatus can be used with the sampling tube to obtain data useful in studying the economic and technical aspects of the development and operation of gas-condensate properties. Introduction The recent discovery and development of gas reserves that contain hydrocarbons that condense with reduction of temperature or Pressure, or both, to form a product known as condensate, has brought many new problems to the oil and gas industries. With further discovery of deep, high-pressure fields it is presumable that many more gas fields of this type will be added to the steadily increasing number. Such gas reserves are found either associated with oil as a gas cap or in separate formations. There seems to be no positive correlation between the physical or geological nature of the reservoir, and the chemical composition or phase characteristics of its contents. Knowledge of the chemical make-up and phase behavior of gas-condensate reserves is needed to cope with many problems. A knowledge of the chemical composition and phase characteristics of the reservoir material is necessary to properly design a gasoline or recycling plant, to estimate natural gas and condensate reserves, to enable the operator to study the economic and technical aspects of various methods of operation and development, and to carry Out the plan of operating subsurface and surface lease equipment. This information is often useful in questions of mineral ownership, proration, legal position, and taxation. It is the purpose of this paper to discuss methods used by the writers to determine the chemica1 composition and phase characteristics of the fluids produced from a condensate well. The scope of the paper includes a discussion and description of the method of sampling, the results of tests on the accuracy of the sampling method, a description of a portable testing apparatus used to examine the phase characteristics, typical results of tests on wells from several condensate fields, and some of the applications of these data to production problems. References to previous work on this subject are cited at the end of the paper. The Problem At reservoir conditions of temperature and pressure, the fluids produced from a condensate well exist in a homogeneous vaporous condition. The consequent reduction of temperature and pressure that occurs as this gas enters and flows up the well tube results in condensation of some of the hydrocarbon material to form a liquid. The relative amount of liquid condensed at any point in the flowing system

Jan 1, 1942

By James F. Kemp

The Bulletin of the Institute for March, 1911, is chiefly devoted to papers upon the iron ores of northeastern Cuba. At that time information about the new developments in the peculiar brown hematites of the region was becoming widely circulated and interest was especially keen. For some years exploration had been conducted with pits and trenches and so great an area had been shown to contain ore in the Mayari, Moa, and Cubitas or San Felipe districts, that the reserves conveniently situated for the consumption of American furnaces were estimated as quite two billions of tons. In the subjoined footnote will be found a list of the principal papers of special interest which have already been published.&apos; The further remark may, however, be made that the

Jan 1, 1915

By Harold V. Pearce

(Chattanooga Meeting, October, 1908.) THE fire which occurred in the fall of 1906, at the works of the Boston & Colorado Smelting Co., Argo, Colo., destroyed entirely the gold- and silver-refinery of the plant; and in view of the development of modern practice in the refining of copper-mattes, etc., the management decided that it would be inadvisable to rebuild that part of the works for the continued use of the process which had been conducted therein for so many years as a metallurgical secret. This decision probably removes altogether from the sphere of practice the " Pearce " method for the separation of gold. At all events, it removes the business reasons which have prevented hitherto the publication of the principles involved. At the suggestion of Dr. Raymond, Secretary of the Institute, my father, Richard Pearce, the former manager of these works, has requested me to prepare a brief description of this process for the benefit of our members. Since I severed my connection with the Boston & Colorado Smelting Co. some time ago, I am indebted for some practical details to the present superintendent, Charles Rees, whose friendly assistance I would gratefully acknowledge. With regard to the history of the inception and development of this process by its inventor, Richard Pearce, I cannot do better than quote freely from his own notes and papers. HISTORY OF THE PEARCE PROCESS.&apos; "In 1874 my entire time was directed to the improvements and additions to the plant at Black Hawk. The changes which I had made in the construction of the furnaces at Black Hawk proved so beneficial that I was requested to introduce the improvements at the branch works at Alma. These changes were carried out as speedily as possible, and proved of great advantage as compared with the old system. "The separation and refining of the gold from the matte now engaged my attention, and since previous experience in the treatment of gold-bearing matte and

Feb 1, 1909

By Thomas M. Price

Sand production for use in hydraulic concrete is probably the most important element affecting the physical characteristics of the resulting concrete in the opinion of most engineers, aggregate producers and contractors of today, who are engaged in the effort to produce stronger concrete per unit of cement used. Their opinion is based on both laboratory and field results. In the past, proper cement production has been the object of most of the study given this subject and while it is still studied by the extensive and well equipped laboratories that are a part of every cement mill, as well as by all governmental laboratories, at the present time the object of most of these studies has been in the field of low heat and quick setting qualities rather than the effect on the strength of the concrete. It is recognized that concrete must have two important qualities; namely, workability with the least water possible, and uniformity. These qualities have been accepted as axiomatic and possible to obtain if the foreman in charge knew his business. Now, however, with concrete produced by plants that mechanically weigh and chart all the ingredients, including water, of a batch of concrete, the foreman cannot cut and fit his aggregates, cement and water to fit his own desires and the secret of the important qualities of workability and uniformity are found to lie largely in the sand, hence the attention given its production at the present time. With this condition in mind the engineers of the United States Bureau of Reclamation and the Six Companies Incorporated in designing the plant for producing the aggregates for the Boulder Canyon Project included every possible means for the production of a sand of a constant and acceptable fineness modulus as well as a constant moisture content, and for attaining these results with as few detrimental ingredients, like silt and vegetable matter, as possible. This aggregate plant (Figs. 1 and 2) is in Hemenway Wash, 7 miles north of Boulder City. It is 4 miles upstream from the low-level mixing plant. At this screening plant 8,234,000 tons of raw aggregate are being

Jan 1, 1934

By H. T. Clark, S. Feigenbaum

THE importance of measuring the temperature of molten steel in the open-hearth furnace has been recognized for many years. Poor temperature control may be costly to steelmaking operations and lead to a lowered quality of the steel. Low or excessive temperatures may shorten the life of the furnace, ladles and molds. Rates of reactions in the furnace and efficiencies of deoxidizers are known to change materially with a change in the temperature of the metal and slag. Ladle skulls and mold and stool stickers cause steel to be scrapped instead of being converted into useful products. Finally, the structure, segregation and surface condition of ingots are affected by the teeming temperature. Mill investigations of the effect of bath temperature upon steelmaking operations have been largely qualitative in character, based upon observations by practical melting men. The physical chemist has used the empirical information available and has reached reasonable and useful conclusions with respect to the various melting processes. The introduction of a reliable direct- reading pyrometer will permit accurate quantitative evaluation of the effects of temperature and should furnish a more rational basis for study of the thermo- chemistry of steelmaking. The problem is not merely one of making a small number of temperature measurements in the open-hearth furnace. This has been done by several methods to a degree of precision that was apparently satisfactory. Considerable effort by a number of investigators has been directed rather to the development of an open- hearth bath pyrometer that would be both accurate and practical for routine measurements. To be practical, the pyrometer should be inexpensive to operate; that is, the installation, operating and maintenance costs should be exceeded by the tangible benefits to the open-hearth operator. Temperatures from 2800° to 3100°F. are encountered in the open-hearth furnace. The surface of the molten metal is covered by several inches of slag, which prevents direct observation of the metal surface for optical or radiation measurements. Both slag and metal are highly reactive at these temperatures and will attack to a greater or lesser extent any material immersed in them. Adequate protection of thermocouples, which of necessity must be brought to the temperature of the bath, has generally resulted in a large, heavy assembly made up of .brittle materials, unsuited for handling on the open-hearth floor. The lie of the equipment was short and maintenance was an important consideration. EARLIER WORK Any one of a number of physical proper- ties of liquid steel could conceivably be used as a basis for temperature measurement. Efforts to the present time, however, have been confined largely to measuring either the thermal electromotive force generated between two dissimilar materials immersed in the steel or the intensity of radiation from the surface of the steel. These

Jan 1, 1946

By R. W. Fountain, W. D. Forgeng

A new constitutional diagram is presented for the cobalt-rich end of the cobalt-titaniurn system. The modifications result from the presence of a new, intermediate, fcc phase, ?, the existence and homogeneity limits of which were established by metallo-graphic and X-ray studies of alloys containing from about 3 to 30 pct Ti. The precipitation of the ? phase from supersaturated solid solution was studied by hardness and electrical resistivity measzsrements, and two distinct stages in the process were observed. COBALT forms the base for a number of precipitation -hardenable alloy systems which may be divided into two distinct categories of practical interest, a) those hardened by intermetallic compounds and b) those hardened by carbide formation. The precipitation of intermetallic compounds from solid solution in cobalt-rich alloys has, however, received very little attention. Although the phase diagrams for some binary systems capable of precipitation have been determined,&apos; there is an almost complete lack of data on the property changes associated with the precipitation, and even less information on the kinetics of the reactions or morphology of the products. More information is available on the precipitation of carbides because of the practical significance in superalloys. A survey of cobalt binary phase diagrams suggested that the cobalt-titanium alloys might provide interesting and useful precipitation-hardenable alloys. The equilibrium diagram as proposed by Wallbaum2 is shown in Fig. 1. Köster and wagner3 have indicated that the maximum solubility of titanium in cobalt is about 10 pct at the eutectic temperature (1135oC), and this decreases to about 7.2 pct at room temperature. The temperature of the allotropic transformation in cobalt is lowered by the addition of titanium, about 5 pct being sufficient to retain the high-temperature fcc modification to room temperature. Wallbaum and Witte 4,5 have indicated that the precipitating phase in alloys containing up to about 29 pct Ti is Co2Ti, a hexagonal Laves phase of the MgNi, type. With slightly higher titanium contents, they also report a cubic modification of Co2Ti of the MgCu2-type Laves phase. Duwez and Taylor6 confirmed the existence of the hexagonal (MgNi2) modification but not the cubic (MgCuz) modification of Co2Ti and suggested that existence of the cubic form may have resulted from impurities in Wallbaum&apos;s alloys. In their work on Laves-type phases, Elliott and Rostoker 7 reported the cubic modification of Co,Ti, but did not confirm the existence of the hexagonal modification. However, Dwight8 in a discussion of the work of Eliott and Rostoker again showed the existence of both modifications of Co2Ti, a result which was confirmed at that time by Elliott and Rostoker. As a result of a study on the iron-cobalt-titanium system, Köster and Gellers suggested the existence of a Co3Ti phase isomorphous with Fe3Ti. Witte and Wallbaum,&apos; however, established the fact that no compound, Fe3Ti, exists in the iron-titanium system, and in a later publication, wallbaum2 stated that Kitster and Geller&apos;s reasoning was not valid, and no compound, Co3Ti, exists. This conclusion was later acknowledged by Köster.10 Preliminary experiments by the present authors to determine the precipitation-hardening characteristics of the cobalt-rich, cobalt-titanium alloys re-

Jan 1, 1960

By Alden Greninger

IN a recent study1 of the deformation of metastable beta copper-zinc and beta copper-tin crystals, it was established that the parallel markings that appear on the surface of these crystals after slight deformation represent lattice transformations. Stereographic analysis showed that in beta copper-tin, the poles of these markings deviated one or two degrees from poles of the form { 133 } . In beta copper-zinc the plane delineated by the markings corresponded to no one crystallographic plane of the matrix lattice; the marking poles deviated from 5° to 11° from poles of the form {110}, and were displaced only a few degrees from (110) zones. Inasmuch as the new transition lattices produced as the result of the deformation are different for each alloy, it was thought at first that the habits of the markings might be the result of a cooperation between matrix lattice and transformed lattice. (Both matrix lattices are body-centered cubic.) Such a cooperative effect is thought to obtain in the formation of Widmanstätten figures, for it is well known that the matrix lattice alone does not determine the habit assumed by a segregate phase. On the other hand, it is not inconceivable that the dissimilarity in mark-ing habit might be due to differences in deformation characteristics of beta brass and beta bronze. Barrett and co-workers2 have shown that slip-line habits in pure iron are markedly different from those in high-silicon ferrite; and although it has been repeatedly demonstrated that plates of a segregate phase do not necessarily form on the slip planes of the matrix lattice, deformation characteristics may be more intimately allied with plate formation when a transformation is made to occur as a result of plastic deformation. However, there is the fact that the orienta-tion of markings in metastable beta copper-zinc is the same whether the markings be produced by quenching, deformation, or liquid-air cooling; likewise, quenching and deformation markings in metastable beta copper-tin are oriented in the same way with respect to the beta matrix.

Jan 1, 1938