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By Burnham E. Field

TAE chemical industry is constantly looking for new materials which either are more resistant to corrosion than those now available or have improved physical properties to meet the requirements of higher temperatures and greater pressures. Attack by acids is-one of the more important forms of corrosion-and in the last few years the development of acid-resistant alloys has been quite rapid. Perhaps the most notable example is that of nitric acid, 'the problem of which has largely been solved by the chromium-iron and chromium-iron-nickel alloys. Sulfuric acid may be handled in lead, iron, or the iron-silicon alloys, depending on conditions. As to hydrochloric acid, no metal or alloy can be called entirely satisfactory for handling. this acid under plant conditions.1 The results of our investigations on the resistance of the nickel-molybdenum alloys to hydrochloric acid have been confirmed by those of Guertler, Rohn, Schulz, Jenge, and others,' but thus far only one such alloy has approached commercial production in Germany; this contains approximately 15 per cent. chromium and 7 per cent. molybdenum with the remainder chiefly nickel. Dr. S. W. Parr, as far back as 1914, developed a complex alloy known as "illium," with a nickel base and containing some molybdenum.3 Dr. Parr was primarily interested in an alloy for lining bomb calorimeters, and while illium does show good resistance to acid it is too expensive for general use. Two United States

Jan 1, 1929

By Frank Reiber

The study of earthquakes long ago developed the fact that by study-ing the travel .times of the various groups of waves from the same earthquake, as received on seismographs :it varying distances, major discont'inuities in the earth's crust, could be reasonably well defined. Using this original discovery, and adapting the mathematical methods originally devised in seismology for determining the depth below the surface at which such discontinuities occur, other investigators were able to develop a new branch of seismology which promises to be extremely useful in extending the boundaries of our information on local conditions Below the earth's surface. As an outstanding example of the applications of this work, we have the so-called " seismograph " exploration of the Gulf Coastal region, which has resulted in the discovery of a large number of salt domes, from many of which oil fields may be developed. The original seismological investigations, from which different major discontinuities in the earth's crust were deduced, as well as these later successful experiments in locating salt-dome structures, involve relatively simple problems. In each case we arc dealing with surface materials in which elastic waves will be propagated with a fairly definite velocity. Under this material we have something quite different', in which the elastic waves will be propagated with a much higher velocity. The transition from one medium to the other is likewise relativtly abrupt. For example, in the Gulf Coastal region the sedimentary formations have a velocity of 6000 or 7000 ft. per sec., while the velocity of elastic waves in the cap rock of a salt dome may exceed 15,000 ft. per sec. Under such conditions, delineation of the formation is a relatively simple matter, and, furthermore, there is very little opportunity for ambiguous results. Development of Elastic-wave Method The success of this Gulf Coast work immediately suggested the advisability of attempting to extend elastic-wave methods to a point

Jan 1, 1929

Chairman James F. Kemp :—I call upon Prof. Albert Sau-veur to open the general discussion on the subject of sound steel ingots. Albert Sauveur, Cambridge, Mass.:—I believe that I have the privilege, this instant, of opening one of the most important, significant and far-reaching discussions ever held before this Institute. I believe that our talk this morning will be heard far and wide, not only on this side of the water, but also on the other side. Everywhere, in short, where steel is manufactured. I welcome the opportunity of expressing my mind in regard to the production of sound steel ingots, a subject about which I entertain Rome very decided opinions. I shall not attempt to discuss the relative merits of the various processes that have been described. I shall, on the contrary, confine myself to a general consideration of the important questions before us. So intensely do I feel regarding the production of sound steel ingots that I have put my remarks on paper in my desire to present my views. I have always remembered my astonishment, not to say dismay, some twenty years ago, when I beheld for the first time a steel ingot, a rail steel ingot, that had been split open from top to bottom. There was the pipe! There was an enormous cavity extending from a short distance from the top to nearly one-third of the length of the ingot; and when I was told that manufacturers seldom discarded more than one-tenth of the total length of the ingot it became evident to me that a large proportion of piped, and therefore, defective, or at least weak and dangerous, rails were manufactured; in fact, probably one rail out of six, nearly 17 per cent., of dangerous rails.

Jan 1, 1914

By L. L. Handy

The most common method of identifying hydrocarbon-bearing strata in a well that penetrates many different formations involves measurement and interpretation of the electrical properties of the formations as determined by electrical logs. Even though this method is used extensively, and even though in a great many instances it is capable of indicating presence of oil or gas, situations arise for which it is extremely difficult, if not impossible, to deduce the presence of hydrocarbons. These situations may involve the following. 1. A thin formation, bounded by highly resistive formations, in which it is impossible to obtain the actual resistivity of the uninvaded zone with existing logging devices. 2. A formation in which invasion has been so extensive that a value for the uninvaded zone resistivity cannot be obtained. 3. A very shaly formation in which the resistivity index, I, is lower than that usually associated with productive formations. 4. Laminated formations comprised of thin productive sands separated by thin shale streaks in which the individual sand and shale streaks are too thin to permit measurement of uninvaded-zone resistivity with existing logging devices. 5. Productive formations in which the water saturation is high. To extend the utility of electric log interpretation to identification of hydrocarbons in all types of formations, there is strong incentive to find a method not subject to these limitations. Some time ago, in connection with research on the wettability of reservoir rock, an investigation was conducted in which the resistivities of cores were measured shortly after they were removed from a core barrel, and again after they had been extracted and restored to their original oil and brine saturation.' The resistivities after extraction were generally lower. Other tests made on the cores indicated that they were more nearly water wet after they were extracted; thus, it was assumed that the observed changes in resistivities were due to a change in wettability of the cores. Other experiments'," have shown that resistivities of rock samples are sharply dependent on wettability. These experiments have shown that oil-wet samples are more resistive than water-wet samples. To obtain an understanding of how the wetting properties of the surfaces of core material affect electrical resistivity, a series of experiments was conducted. Two groups of core samples were prepared for testing. One group contained brine, but no residual oil. The other group was saturated with brine, flooded with oil to a low water saturation, then flooded with brine to a final residual oil saturation. Resistivity measurements were made on each group. Both groups were then flooded with the original brine to which a chemical had been added that renders sand and clay surfaces preferentially oil wet, a so-called reverse-wetting agent. very little change in resistivity was observed in cores containing only water. The group containing residual oil, however, showed resistivity increases of 100 to 200 per cent. These experiments showed that the resistivity of a core containing oil could be altered by changing wet-tability of the core. Moreover, the possibility was introduced that reverse-wetting agents might be employed as the basis for a logging method for identification of oil-bearing strata. Since behavior of a porous rock containing gas and water might be expected to be similar to that of a rock containing oil and water, such a method should also be applicable to identification of gas-bearing zones. In principle the wettability of the invaded zone could be reversed without altering conductivity of the interstitial water or the hydrocarbon saturation therein. Those strata showing significantly increased invaded-zone resistivities would, therefore, contain hydrocarbons; those with no significant change would be filled only with water. Addition of a reverse-wetting agent to a hydro carbon -bearing zone which is, by nature, already preferentially oil wet would not result in an enhancement of its resistivity. It is generally believed, however, that most hydrocarbon-bearing strata are preferentially water wet.

By J. F. Martin, J. E. Friedline, L. M. Melnick, G. E. Pellissier

A method has been developed for determining gases in steel in which the gases are extracted by vacuum fusion and analyzed by mass spectrometry. This method is especially applicable for determining small amounts of oxygen and nitrogen. The lower limit of detection for both oxygen and nitrogen is 0.0001 pct with an average deviation of about 0.0001 pct for oxygen and 0.00008 pct for nitrogen. Hydrogen analyses by this method are in good agreement with analyses by vacuum tin-fusion. A complete analysis of all gases extracted from a steel sample can be accomplished in 40 min. It has long been known that certain of the gaseous elements exert particular effects on the physical and mechanical properties of steel. With the recent advent of new experimental steelmaking practices it is now possible to obtain steels with extremely low contents of such elements as oxygen and nitrogen. Present methods for determining these two gases are of insufficient sensitivity as applied to steels made by these newer practices, and therefore a new technique was considered necessary. A review of the literature showed that the conventional vacuum-fusion method1 was the procedure most suitable for modification to obtain a sensitive method for determining the gaseous elements present in steel simultaneously. However, for trace amounts of gases it is impractical to increase the sample size because of the physical limitations of the apparatus and the increased degassing time which would be necessary. Also, when only one of the desired gases is present in trace amounts, quantitative separation by conventional vacuum fusion is almost impossible. Since small analytical mass spectrometers are now commercially available, it was decided to use this instrument in conjunction with conventional vacuum fusion for both qualitative examination and quantitative determinations of the gaseous elements in steel. This technique has already been used with success for the analysis of copper and lanthanum.2"4 APPARATUS A vacuum-fusion unit was first designed and built, Fig. 1. This unit was designed especially for the determination of small amounts of nitrogen and/or oxygen in steel since an acceptable method (vacuum tin-fusion)5 was already in use for the determination of hydrogen in steel. The vacuum system was con- structed of Pyrex glass throughout. Mercury check valves were used in place of stopcocks in the high-vacuum section of the system. Ferromagnetic samples are normally introduced into the vacuum system through a mercury lift. In case of a break in the lift, the mercury is prevented from entering the furnace by a self-locking, mercury safety check valve, Fig. 2. This check valve, developed at our laboratory, is a modified T/S ball-and-socket joint placed in the sample inlet system between the mercury and the furnace. A sudden entry of mercury or air pushes this valve into the closed position, completely blocking the top of the mercury lift. The check valve is held in the closed position by the vacuum of the apparatus. A separate entrance tube also was placed in the system, so that samples which would amalgamate with mercury, or which are nonmagnetic, could be introduced into the furnace. A slightly modified Guldner-Beach furnace is used in this system.8 The optical flat was connected to the system by a ground-glass joint to facilitate cleaning, a quartz delivery tube was substituted for Pyrex, and the crucible was used uncovered. Fusion takes place in a high-purity graphite crucible insulated by — 200-mesh high-purity graphite powder. The crucible set (crucible and funnel) is suspended in a quartz crucible. The furnace envelope and the sample inlet system are exhausted by 2 single-stage, mercury-diffusion pumps in series. The first of these is a high-speed pump, which will work only with a very low backing pressure. This pump is used to exhaust the gases from the furnace as rapidly as possible. The second mercury-diffusion pump is used as a backing pump for the first; the capacity of this pump is much lower. However, it will work efficiently against a back pressure of 3 mm of mercury. To assure positive pumping, a modified Naughton and Uhlig condenser7 is used. With the use of proper valving the second pump is also used as a circulation pump in the catalyst system.

Jan 1, 1959

By R. Hadfield

Since the writer has been intimately connected with the development of manganese steel for many yearsm some remarks upon the early work wutg regard to the rolling and forging of the material might be of interest…

Jan 1, 1915

By Dwight Farnham

Description of Quarry THE shale used at the Renton plant of the Denny-Renton Clay Coal Co., for the manufacture of vitrified paving brick occurs in a hill rising from 200 to 300 ft. above the level of the valley in which the plant is situated. The shale deposit, which is of unknown thickness pitches about 10° to the southeast. The 150-ft. face worked extends approximately east and west, so that the clip, as shown by the photograph, is to the left and into the hill. The shale is overlain with about 50 ft. of gravel, 70 ft. of clay, and 30 ft. of mixed loam and gravel, making altogether from 125 to 150 ft. of overburden. Disposal of Overburden The overburden is removed by sluicing. For this purpose a No. 2 Joshua Hendy giant is used, throwing a 12-in. stream', and having 60 lb. pressure at the nozzle. The water is drawn through an 8-in. pipe from Cedar river, about 1,000 ft. distant, by means of a Worthington four-stage centrifugal pump, direct connected with a 100-h.p. motor placed just south of the factory, and 1,500 ft. from the nozzle This plant handles the material satisfactorily to a height of about 75 ft. above the level of the top of the shale. When the higher levels are worked, an auxiliary plant consisting of a four-stage Byron Jackson centrifugal pump with a 100-h.p., belt-connected motor, is thrown into the system. This plant is situated on top of the shale and can be discerned at the extreme right of the trestle work in Fig. 1.

Jan 9, 1914

By Clair Upthegrove, E. S. Rowland

The widespread interest in the alloys of beryllium with copper is due principally to the fact that certain compositions show very favorable precipitation-hardening characteristics and are, in fact, the stronges nonferrous alloys known at the present time. Investigations have been conducted by Masing and Dahl and others on the physical characteristics of ternary beryllium alloys, in an attempt to produce precipitation hardening effects with a smaller amount of beryllium than that required in the binary copper-beryllium alloys (2.0 to 2.5 per cent Be). The results of these investigations show that ternary alloys of beryllium with Cu-Sn, Cu-A1 and Cu-Zn, among others, exhibit promising improrcmc~nts in physical properties after precipitation-hardening treatment and, while the increases in properties obtained are not as high as those reahzed from the binary copper-beryllium alloys, excellent properties arc obtaincd with beryllium contents averagirlg about one-half the amount reqnired in the binary alloys. This paper presents the results of an investigation of the equilibriun relations of certain alloys containing copper, tin and beryllium. The alpha-phase boundary of the ternary system is given for alloys containing from 0 to 1 per cent beryllium. The equilibrium conditions beyond the alpha-phase boundary are presented for alloys containing up to 32 per cent tin and 1 per cent beryllium. The data were collected by means of quenching experiments, microscopic examination and thermal analysis The results of some powder-method X-ray determiniations on the alloys, conducted by Mr. William Mikulas and Prof. Lars Thomassen at the University of Michigan, are used as evidence in this paper. The con

Jan 1, 1935

By E. S. Rowland, Clair Upthegrove

The widespread interest in the alloys of beryllium with copper is due principally to the fact that certain compositions show very favorable precipitation-hardening characteristics and are, in fact, the stronges nonferrous alloys known at the present time. Investigations have been conducted by Masing and Dahl and others on the physical characteristics of ternary beryllium alloys, in an attempt to produce precipitation hardening effects with a smaller amount of beryllium than that required in the binary copper-beryllium alloys (2.0 to 2.5 per cent Be). The results of these investigations show that ternary alloys of beryllium with Cu-Sn, Cu-A1 and Cu-Zn, among others, exhibit promising improrcmc~nts in physical properties after precipitation-hardening treatment and, while the increases in properties obtained are not as high as those reahzed from the binary copper-beryllium alloys, excellent properties arc obtaincd with beryllium contents averagirlg about one-half the amount reqnired in the binary alloys. This paper presents the results of an investigation of the equilibriun relations of certain alloys containing copper, tin and beryllium. The alpha-phase boundary of the ternary system is given for alloys containing from 0 to 1 per cent beryllium. The equilibrium conditions beyond the alpha-phase boundary are presented for alloys containing up to 32 per cent tin and 1 per cent beryllium. The data were collected by means of quenching experiments, microscopic examination and thermal analysis The results of some powder-method X-ray determiniations on the alloys, conducted by Mr. William Mikulas and Prof. Lars Thomassen at the University of Michigan, are used as evidence in this paper. The con

Jan 1, 1935

By J. E. Hilliard, J. W. Cahn

In this paper it is suggested that the degree of contiguity (or contact) between adjacent grains be described by three parameters which can be rigorously determined from measurements on a random plane of polish. An expression is also derived for the number of contacts per unit volume and it is shown that this quantity can-not, in general, be estintated from measurements on a random plane. IN a recent contribution1 Gurland has proposed various parameters for describing the degree of contiguity (or contact) between grains of the same phase in an alloy. To relate these parameters to measurements on a random two-dimensional section, it was necessary in most cases to make some assumption about the form of the structure. Since Gurland was specifically interested in sintered carbide structures, he chose, quite reasonably, to assume that the grains were constant-size spheres and that all the intersections were flat areas of constant radius. Since, as we will show, the relationships between the parameters and the measurements are strongly dependent on the grain shape and size distribution, it is evident that these assump tions will not be satisfactory approximations for a

Jan 1, 1960

By L. W. Pommier, F. B. Brien, A. K. Bhasin

The diflerential movement of solid particles through solid-liquid suspensions is very important to many branches of engineering. The flow of suspensions around immersed bodies is mainly of a turbulent nature. Problems are encountered when attempts are made, as is the general practice, to extrapolate the velocity and resistance relationships of Newton, pertaining to Newtonian systems, into non-Newtonian solid-liquid suspensions. The conventional velocity and resistance relationships for turbulent flow in fluids when applied to suspensions, do not take into consideration the two very important variables: suspension particle size and solid volume fraction. A study of the effect of suspension particle size (dgb) on the velocity of falling balls leads to the concept of a critical particle size (dgc) at which the suspensions will be Newtonian. This leads to the classification of static suspensions into two types: suspensions consisting of particle of diameter dgh > dgt, and those with dgh, < dgr. Separate velocity and resistance equations for these two types of suspensions have been proposed, taking into account both the solid particle size and solid volume fraction. The agreement between the velocities predicted from the proposed equations and the measured velocities, confirms their validity. The resistance force offered by suspensions to the movement of immersed bodies has been calculated from the proposed equations, and the effects of suspension particle size and solid volume fraction on the resistance force and velocity have been examined. The movement of immersed bodies in solid-liquid suspensions is of great importance in many areas of engineering such as minerals processing, oil well drilling, suspension flow in pipelines, and hydrometallurgy. A number of mineral dressing processes deal essentially with the movement of solids in suspensions—in particular, classification, thickening, filtration, ore washing, and gravity concentration—thus a study of the fluid characteristics of suspensions is of theoretical and practical interest.&apos; A rigorous analysis of the mechanisms of momentum transport of a solid-liquid system is complex indeed. The rheological properties of the suspensions deviate from those of liquids, varying, for example, with density, solid volume fraction, size and shape of the solid phase of the suspension, and with the density and viscosity of the liquid phase. The flow of suspensions around immersed bodies is mainly of a turbulent nature and hence studies of the turbulent flow characteristics of suspensions are of par- ticular importance. Problems are encountered when attempts are made to extrapolate the velocity and resistance relationships of Newton, pertaining to Newtonian systems, into non-Newtonian solid-liquid suspensions. Due to the numerous variables present in a suspension, certain limitations and assumptions become necessary in order to produce quantitative relationships for predicting their effects. The solid particle size and the solid volume fraction are two of the more important variables. By comparing the measured and calculated Newtonian velocities of falling balls in simple static suspensions, the existing velocity and resistance relationships have been modified to take these variables into account. In order to keep the study less complex, all other variables such as the characteristics of suspending liquid and shape of the particle are maintained constant. Objective The objective of the present investigation is to modify the Newtonian velocity and resistance equations in order to take into account the suspension particle size and solid volume fraction. Theory Liquids are classified on the basis of viscosity, which may be defined as the relationship between applied shear stress and resulting rate of shear.&apos; pure single-phase fluids composed of small light molecules behave as Newtonian liquids, having a single viscosity pa-

Jan 1, 1971

By A. O. P. Casbarian

An analytical method is developed to determine the variation of the ultimate lateral resistance of a plate in a cohesionless soil with depth. This analysis is based on a modification of Rankine&apos;s classical earth pressure theory and the theory of plasticity as applied to soils. The ultimate resistance is defined as the product of the effective stress at the midpoint of the plate, the area of the plate and a dimensionless variable termed the ultimate resistance factor. This variable has been plotted us the depth ratio: i.e., the ratio of of the depth of embedment us the height of the plate. The resistance of a plate may then be calculated using the values af the ultimate resistance factor from the chart provided or the equation may be programmed for use in an analysis of anchor systems in cohesionless soils. It is emphasized that the analysis is semitheoretical. The theory has been compared with experimental results reported in the literature and results indicate general agreement. Actual field tests are necessary to further verify this theory. INTRODUCTION With the exploration for oil offshore in waters all over the world, it is of importance to determine the behavior of the various soils in relation to their ultimate resistance to deformation. Examples of such problems are the holding capacity of anchors and the lateral resistance of piles. Very little information is available in the published literature on the design and performance of anchors, in either cohesive or cohesionless soils. The analysis developed in this report is the first step in obtaining a solution for the determination of anchor holding capacity in a cohesionless material. DISCUSSION The theory used in the analysis is based on the ultimate strength of the soil and is the maximum resistance developed by the plate against further movement. In such a state the elastic deformations are disregarded in comparison with the plastic deformations. Hence, the plate can be considered as completely rigid. The theory of plasticity determines the three unknown stresses at any point by means of two equilibrium conditions for a small earth element in combination with the failure condition. However, the exact solutions can only be carried out in a few simple cases such as, for example, when the rupture or failure lines are straight (Rankine theory) or with spiral and straight rupture lines (Prandtl theory).l Kiitter 2 derived a single equation expressing the variation of the stress in any given rupture line. To utilize this equation, it is necessary to know the stress in the rupture line at a certain point. Unfortunately, this is difficult to obtain unless the rupture line intersects the free surface at a certain angle or when the earth is cohesion-less and unloaded. A method to overcome this is to consider only the boundary conditions at both ends of a rupture line without investigating the equilibrium of the earth above the rupture line. This assumes that the rupture lines meet the surface at statically correct angles, so that boundary stresses may be determined. As Kiitter&apos;s equation furnished a relation between these stresses, the unit earth pressure may be calculated at the point where the rupture line meets the wall. Another way in which Kotter&apos;s equation may be applied is in investigating the equilibrium of a soil mass above a rupture line. This method assumes that the failure or rupture line is known and that the boundary stresses in the rupture line at the ground surface can be determined. In this case it is possible to determine the earth pressure from the equations of equilibrium.

Jan 1, 1967

By C. Schlumberger

SINCE the beginning of .the year 1928 the senior authors and their associates have applied a series of procedures which makes possible the detailed study in situ of the formations traversed by a drill hole before the casing has been landed. They have given the name "electrical coring" to the ensemble of these processes, which now replace in a large measure the mechanical coring performed by the drillers, and permit the gathering of bottom-hole data hitherto unobtainable. Three years have elapsed since the technique and interpretation of these measurements emerged from the experimental stage and entered the field of industrial application on a large scale. The total length of drill holes so far surveyed by the authors and their associates, all over the world, amounts to several millions of feet. Practical and strongly built equipment has been evolved, which permits the examination in a short time of an open hole several thousand feet long. No comprehensive paper has yet been published discussing the essential principles of the processes applied and bringing into evidence their economic interest. This is the object of the present paper.1 Numerous examples of field work performed under varied geological conditions are given, constituting a concrete illustration of the services rendered by the new methods. The study in situ of the formations penetrated by a drill hole is based on the measurement of a given physical factor or parameter associated with these formations. Generally. the measurements are made syste-matically along the whole length of the open hole. The physical factors or parameters which are now utilized by us to this end are: (1) the resistivities of the rocks; (2) their porosity; (3) their electrical anisotropy; (4) their temperature; (5) the resistivity of the muds. In order to

Jan 1, 1932

By David W. Pasho

The success of a collector vehicle, designed to recover manganese nodules under the conditions which exist in deep ocean mine sites will in part be determined by the effectiveness of pick-up and running gear mechanisms. For the purpose of qualitative comparison, some specific aspects of seafloor interactions with various concepts are reviewed utilizing existing data on seafloor characteristics and running gear/tool interaction with soils.

Jan 1, 1976

By L. Russell, van Wert

During an investigation in which the solubility relations of the phases in Muntz metal (60 per cent. copper, 40 per cent. zinc) were under study, certain phenomena that had no immediate connection with the main problem were observed, which were thought sufficiently interesting to study further. Because of lack of time, only a preliminary survey was made of two of these; namely, the cleavage structure developed under certain conditions in a 60:40 brass and abnormal grain growth in this alloy. Cleavage Structure in Heat-treated Muntz Metal Carpenter noted many years ago that cold-working a brass of the Muntz metal type, which had been quenched previously from within the beta field, results in a partial breakdown of the supersaturated beta solution and the precipitation of the solute (the alpha solution) in the cleavage planes of the beta grains. This manner of rejection of a solute from a metastable solid solution is not peculiar to this particular alloy, for among others, it occurs in the cold-working of certain austenitic steels; for example, the austenitic nickel steels. In these ferrous alloys, cold deformation produces a partial decornposition of the austenite, with the formation of martensitic "needles" and zigzags in the austenitic poly-hedra. It is interesting to note that while the two solid solutions— austenite and quenched Muntz metal— are metastable and in their mode of decomposition behave quite alike when deformed in the cold, the metastability of each results from a different cause; viz., that of the austenite from the fact that it is a supercooled solution (its solvent. gamma iron, at ordinary temperatures is below its normal stable range whereas the metastability of the quenched Muntz metal is the result of supersaturation. When a 60:40 brass is quenched from above 800" C.—that is, from within the field where the beta phase alone is stable—this solution is retained practically intact and the alloy so cooled is found to consist almost entirely of polyhedra of this solution with only a little alpha present ordinarily at the boundaries of the beta grains—the result of a slight

Jan 1, 1929

By van Wert, L. Russell

During an investigation in which the solubility relations of the phases in Muntz metal (60 per cent. copper, 40 per cent. zinc) were under study, certain phenomena that had no immediate connection with the main problem were observed, which were thought sufficiently interesting to study further. Because of lack of time, only a preliminary survey was made of two of these; namely, the cleavage structure developed under certain conditions in a 60:40 brass and abnormal grain growth in this alloy. Cleavage Structure in Heat-treated Muntz Metal Carpenter noted many years ago that cold-working a brass of the Muntz metal type, which had been quenched previously from within the beta field, results in a partial breakdown of the supersaturated beta solution and the precipitation of the solute (the alpha solution) in the cleavage planes of the beta grains. This manner of rejection of a solute from a metastable solid solution is not peculiar to this particular alloy, for among others, it occurs in the cold-working of certain austenitic steels; for example, the austenitic nickel steels. In these ferrous alloys, cold deformation produces a partial decornposition of the austenite, with the formation of martensitic "needles" and zigzags in the austenitic poly-hedra. It is interesting to note that while the two solid solutions— austenite and quenched Muntz metal— are metastable and in their mode of decomposition behave quite alike when deformed in the cold, the metastability of each results from a different cause; viz., that of the austenite from the fact that it is a supercooled solution (its solvent. gamma iron, at ordinary temperatures is below its normal stable range whereas the metastability of the quenched Muntz metal is the result of supersaturation. When a 60:40 brass is quenched from above 800" C.—that is, from within the field where the beta phase alone is stable—this solution is retained practically intact and the alloy so cooled is found to consist almost entirely of polyhedra of this solution with only a little alpha present ordinarily at the boundaries of the beta grains—the result of a slight

Jan 1, 1929

By N. B. Davis

I . INTRODUCTION WHILE working with a number of very sticky cracking clays from western Canada the writer became interested in a study of the cause of the excessive plasticity, This led to a review of the rather bulky literature on the subject and the finding that plasticity still remains to be satisfactorily explained. Most of these investigations seem to have been carried on solely from the chemical viewpoint, the geologic aspects having been ignored. In nearly every case, the investigators have worked with the higher-grade clays of low to medium plasticity, such as the kaolins, the excessively plastic ones having generally been neglected, partly because of their limited application, yet the author believes that these are

Jan 2, 1915

By Lawrence B. Wright, Lester G. Morrell

ON the steep slopes of the Kootenays, 15 to 20 miles south of Nelson, B. C., are a number of ore occurrences (Fig. 1). One that has many features of mining and geological interest is the Ymir Yankee Girl Gold Mines Limited. Discovery of this property was made in 1899 at an outcrop on the hillside, some 2500 ft. above the village of Ymir. This proved to be a branch vein 20 ft. long leading to two main veins, the Yankee Girl and the Spur (Fig. 5). The ore pattern as now delimited shows a remarkable increase in ore area with depth below the outcrop. This recent development is of interest particularly in view of the fact that the property was nearly condemned, professionally. Another interesting feature, which has a bearing upon its history, is the persistent excess of tonnage produced from period to period over visible reserves. This is not ascribed to lagging mine development, but to detailed vein characteristics, which we will endeavor to make clear by giving a description of the veins and their surroundings. HISTORY AND PRODUCTION Little interest was evidenced in this district until the building of the railway in 1893 provided easy access and the discovery of the Ymir mine [t] in 1896 attracted attention. As a result, the Ymir Yankee Girl group of claims was staked in October 1899. In 1907, an American syndicate took over the property and subsequently extended the 50-ft. drift and opened the present 400 and 540-ft. levels. In 1908, the Syndicate, without recording any shipments in the meantime, dropped its lease, which was taken up by H. L. Rogers, who bonded the Yankee Girl group. Rogers shipped 2622 tons of ore, mainly from the uppermost stope in the mine, which is reported to have yielded

Jan 1, 1938

By E. Seidl

THE basic material for testing aluminum, copper and zinc is a cast metal, principally in the form of wire bars (Figs. 1 to 3) and plates for the produc- tion of sheets or strips, (Figs. 4 to 7). Experience has proved that the chemical and crystallographic proper-ties of such cast metal exercise a certain influence when it is being worked, which is usually done while the metal is hot. In a chemical sense the slight impurities, which even the purest industrial metal contains, have a disturbing effect. They settle either along the outside limits of granulation, as in the case of aluminum and copper, or else in the interior of the crystal, as in the case of zinc; but frequently are also found accumulating at certain points (formation of the blowholes and skin) (Fig. 7). The crystallographic character of the metals is either that of uniformly fine granulation, or else there occurs a certain distinct casting texture marked by sharply defined cooling conditions and consisting of crys-tals of a pronounced stalk-like or blade form. Since we generally distinguish between a crystal texture and a crystal structure, the term crystal texture is used here for the arrangement of the crystals relative to each other and their microscopic composition; crystallic structure is used to mean the radioscopically ascertain-able structure of the crystal. The influence of the impurities and of the crystalline character on the working of the metals has been fre-quently pointed out in practice as well as in science.

Jan 11, 1927

By J. H. Hollomon, L. D. Jaffe, M. R. Norton

In the practical heat-treatment of steel the decomposition of austenite usually occurs during cooling rather than at constant temperature. Nevertheless, the course of this decomposition has generally been studied only isothermally. Isothermal studies are not only simpler experimentally, but have the great theoretical advantage that one of the variables, temperature, is constant. It is the purpose of this paper to outline the principles that govern the relations between isothermal and anisothermalt‡ decomposition of austenite, to present and systematize the available experimental information, and to indicate the gaps in the existing knowledge. Some of the experimental information is the result of new work.§ Most of it is derived from scattered data in the literature. Many of these data were obtained incidentally in the course of research on other subjects and their significance has not been pointed out and perhaps not understood. It is hoped that this paper will aid future planning of more extensive research on anisothermal decomposition. Method In order to study the relations between isothermal and anisothermal decomposition, it appears fruitful to view anisothermal decomposition as taking place at a series of constant temperatures1 (except for the martensite reaction, which does not occur isothermally to an appreciable extent). When the time the steel is at each temperature is finite, the over-all amount of the reaction is considered to be the sum of the amounts occurring at each of the successive temperatures. During continuous cooling or heating, the time the steel is at each temperature and the difference between successive temperatures can be considered to approach zero. The over-all amount of transformation will then be given by integration over the range of temperatures involved. This point of view is advantageous in that it considers anisothermal transformation to be a series of isothermal transformations. The problem thus becomes one of determining the effect of partial decomposition at any given temperature upon subsequent decomposition at another temperature. Single Anisothermal Reaction Consider a phase brought to a temperature at which it is unstable, held there until it has partially transformed, and then brought to another temperature at

Jan 1, 1947