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By L. G. Graper, E. L. Ramsey

THE present program of increased production of armament and lend-lease material for mechanized war has created a problem for the shops that must do the machining. They have naturally turned to the steel producers to provide them with a steel that can be accurately machined with the greatest possible speed. The adding of sulphur to steel as an aid to machinability has long been practiced; however, it may cause red shortness in rolling and may result in billets with seams and cracks, which must be removed before rolling can be continued. This conditioning of billets slows down production and adds to the cost of making steel. Experience with various grades of sulphur steel made to different specifications has shown that Bessemer sulphur steels roll better than similar grades made in the open hearth, and also that low-carbon steels that are open or semi-killed as tapped roll better than completely deoxidized or killed steels. This has led to the belief that oxygen plays an important part in the rolling qualities of sulphur-bearing steels. It is generally held that the red shortness of sulphur steels is due to the low melting point of the sulphide compounds that separate out at the grain boundaries when the steel solidifies. At the rolling temperature of steel these sulphide compounds melt and cause cracking. ADDING SULPHUR AS A SULPHITE These difficulties can be avoided if sulphur is introduced into the steel by means of an anhydrous sulphite, such as sodium sulphite or sodium bisulphite, which-upon decomposition-forms sulphur dioxide. It is assumed that, in this case, the oxygen of the sulphur dioxide forms part of the sulphide inclusions in the steel, and raises their solidification temperature enough so that the formation in the steel of a low-melting eutectic is prevented. The result is the prevention of hot shortness and a more uniform distribution of inclusions. Fig, I shows photomicrographs of steels made with sulphur, while Fig, 2 illustrates the structure of steels made with sodium bisulphite. These samples were cut from the steels as cast-that is, before rolling and were polished and lightly etched to bring out the grain boundaries. Fig. I shows that sulphide inclusions segregate more or less at the grain boundaries, and it can be seen how the continuity of these low-melting inclusions would cause red shortness. Fig. 2 shows that the sulphide inclusions are more or less uniformly distributed throughout the matrix. This arrangement of inclusions has no apparent effect on the rolling qualities of a steel. This statement has been substantiated by the observation of the rolling of over 6000 tons of steel made with a sulphite addition. RESULTS As stated before, the sulphur dioxide is added to steel by means of the decompcsi-

Jan 1, 1942

By J. A. M. van Liempt

Since the discovery of von Laue, that a crystal forms a natural grating for X-rays, our knowledge of the structure of solids has gone forward with rapid strides. This progress is not only of purely scientific interest, but has also yielded direct technological results. One of the most valuable results is the broadening of our knowledge of the structure of pure metals and alloys. To promote these studies it is often desirable to have at our disposal pieces of metal consisting of one single crystal. As is so often the case in the natural sciences, we obtain the best results by making our earliest experiments on pure, simple materials and avoiding unnecessary complications. The Cryogen Laboratory at Leyden followed this method with much success, because the work was done at such low temperatures that the heat movement of the atoms was almost absent. Similarly we can simplify the studies of metals by leaving out of consideration the influence of the grain boundaries and the mutual influence of the crystals by using unicrystalline instead of polycrystal-line metal. Methods of making single crystals have been scientifically studied during the past few years. Some methods were already known in the arts, but these have been improved and new methods have been developed. The methods for making metallic single crystals may be divided into the following groups: A. From the liquid state B. From the gaseous state C. Electrolytically D. By recrystallization in the solid state Method A 1. Tamwmnn's Method1—Tammann succeeded in making bismuth single crystals of a maximum length of 20 cm. by undercooling the molten metal 0.1 to 0.3' G. below its melting point in glass tubes of a maximum

By Keith C. Hendrick

The mining industry of Canada, stretching from coast to coast and reaching into the most remote regions of the country, is of fundamental importance to the national economy and the well being of many communities outside the main urban areas. The production, processing and transportation of a host of mineral products provide employment for about 9% of the country's labour force; and their shipment to export markets provides an important contribution to the balance of payments. In 1976 Canada's metal and mineral production had a value of $5.24 billion, of which zinc and lead accounted for $862 and $129 million respectively, or 19% of the total. By all standards the Canadian zinc and lead industry is large and, therefore, important to the country as a producer and the world as a supplier. This report will review the development, describe the present status and discus current problems and future potential of the industry. The discovery and successful development of the major lead-zinc deposits at Kimberley, British Columbia, provided Canada with a solid base from which to grow. The breakthrough in metallurgical technology using differential flotation to separate the lead and zinc sulphides and the refining of high purity metal by electrolytic methods not only helped Canada to compete with other world producers but also provided a new source of these metals at prices and qualities that encouraged the development of new end uses.

Jan 1, 1977

By J. A. M. van Liempt

SINCE the discovery of von Laue, that a crystal forms a natural grating for X-rays, our knowledge of the structure of solids has gone forward with rapid strides. This progress is not only of purely scientific interest, but has also yielded direct technological results. One of the most valuable results is the broadening of our knowledge of the structure of pure metals and alloys. To promote these studies it is often desirable to have at our disposal pieces of metal consisting of one single crystal. As is so often the case in the natural sciences, we obtain the best results by making our earliest experiments on pure, simple materials and avoiding unnecessary complications. The Cryogen Laboratory at Leyden followed this method with much success, because the work was done at such low temperatures that the heat movement of the atoms was almost absent. Similarly we can simplify the studies of metals by leaving out of consideration the influence of the grain boundaries and the mutual influence of the crystals by using unicrystalline instead of polycrystalline metal. Methods of making single crystals have been scientifically studied during the past few years. Some methods were already known in the arts, but these have been improved and new methods have been developed. The methods for making metallic single crystals may be divided into the following groups: A. From the liquid state B. From the gaseous state C. Electrolytically D. By recrystallization in the solid state METHOD A 1. Tammann's Method. 1-Tammann succeeded in making bismuth single crystals of a maximum length of 20 cm. by undercooling the molten metal 0.1 to 0.3° G. below its melting point in glass tubes of a maximum

Jan 1, 1928

By M. J. Sinnott, H. B. Probst

AN extensive survey of the factors which affect austenite grain growth has already been made.' These factors are temperature, time at temperature, rate of heating, initial grain size, hot-working, alloy content, ofheating,initialand rate of cooling from the liquidus-solidus temperature. In the present work, a vacuum-melted temperature.electrolytic iron was used and the variables studies were temperature, time at temperature, and prior ferrite grain size. Other factors were maintained constant. The iron used in this study was vacuum-melted electrolytic iron of nominal composition of impurities of 0.07 wt pct. It was supplied as a ½ in. round cold-drawn bar. This iron was tested in three conditions: as-received, annealed 6 hr at 1200°F, and annealed 6 hr at 1600°F. Samples were ? in. disks cut from the bar. The prior anneals were carried out in vacuum and the isothermal treatments were carried out in vacuum-sealed Vycor tubing. The thermal etch technique was employed to determine the austenite grain size. Prior to sealing the test specimens, one surface of the sample was polished metallographically. This surface, after heating, was examined to determine the austenite grain size, since the austenite boundaries are revealed by thermal etching. This is essentially the only technique available for measuring the austenite grain size of low carbon steels or pure irons without altering the composition. It has been shown to yield results that are in agreement with other methods used for determining austenite grain sizes.' The specimen size was quite large compared to the grain size measured, so inhibition of growth due to size effects is probably negligible. After vacuum sealing, each sample was placed into a furnace at temperature and at the completion of the run was quenched into a mercury bath. The growth temperatures used were 1700°, 1800°, 1900°, and 2000°F controlled to -~10"F. Growth times were varied from 10 to 240 hr. The long times were used in order to eliminate the nucleation and growth effects occurring during the initial transformation. Time was measured from the introduction of the capsule into the hot furnace to the time of quench. Grain-size measurements were made with the use of a grain-size eyepiece of a microscope. By determining the number of grains per square millimeter at X100 and taking the square root of the reciprocal of this number, the average linear dimension of the grains was determined. Figs. 1 and 2 are plots of these data as a function of time and temperature for the various conditions investigated. The variation of D, the linear dimension of the grains, was assumed to follow the equation3 D = A tn. The curves of Fig. 1 were obtained from the data by the use of the least-squares method of analysis. Fig. 1 is for the growth of the as-received stock and Fig. 2 is for growth after prior treatments. Differentiating the foregoing equation gives an expression for the rate of growth dD/dt = G = nAtn-1 = nD/t. Both D and G as functions of t are given in Table I. It should be noted that G is a function of time; the growth rate is rapid at early stages and decreases with increasing time. Since increasing temperature increases the growth rate, it has been common practice to use the empirical relationship G = Go e-Q/RT to relate temperature to growth rate. The growth rate customarily has been taken at constant values of D on the basis that the rate of growth is related to the boundary surface tension and this is measured by the curvature of the boundary. At constant D values, the growth rate is a function of time and temperature. The growth rate can be related however to temperature at constant time, and this has the advantage that under these conditions the growth rate is a function only of temperature. Obviously the Q values, activation energies, obtained for each assumption will not be the same and the question of which is the more correct is a moot one, since the assumed exponential relationship in either case has no particular theoretical significance. By plotting G, at constant grain size, vs 1/T, the activation energy over the temperature range of 1800" to 2000°F is found to vary from 30,000 cal per mol at the smaller grain sizes to 50,000 cal per mol at the larger grain sizes. The 1700°F data do not correlate with the data at higher temperatures. The activation energies for the 1200" and 1600°F prior annealed materials were calculated as 50,000 and 62,000 cal per mol, respectively, using the reciprocal time to a given grain size as a measure of the growth rate. Plotting G, at constant times, vs 1/T yields an activation energy of 12,300 cal per mol for the tem-

Jan 1, 1956

By F. H. Buttner, H. Udin, J. Wulff

Using a modified Udin, Shaler, and Wulff technique, the surface tension of gold Udin, purified helium was found to be 1400 ± 65 dynes per cm for the temperature range 1017° to 1042°C. IN the original Udin, Shaler, and Wulff technique for measuring the surface tension of copper: variously weighted wires were allowed to extend or contract in a copper cell held at elevated temperatures in vacuum. By plotting stress vs. strain for a wire array in one test, the stress at zero strain is obtained. This is the point where the contractile forces resulting from surface tension are balanced by the applied load, according to the expression: y = e=o r [1] where y is the surface tension in dynes per cm; a,,,, the stress at zero strain in dynes per cm; and T, the radius of the wire in cm. The assumption that the wires deform viscously permits the drawing of a straight line through the points on the stress-strain plot. Justification of the assumption has received further experimental support recently.'-' The presence of grain boundaries in the wires requires a correction to the original expression used." Thus: y = d4=T [l- (dl) (ar)Y1 [2] where, n/l is the number of grain boundaries per unit length, and a, the ratio of grain boundary tension to free surface tension. Alexander, Kuczynski, and Dawson in studying the creep of gold wire in vacuum were unable to obtain reproducible values of the surface tension of gold. In plotting stress vs. strain for progressively longer times, they found that the stress at zero strain drifted with time from positive stress values to negative values. Similarly, for the surface tension of silver, reproducible values were obtained only when a purified helium atmosphere was substituted.' Evidently the evaporation rate of silver in vacuum is too high at the temperatures employed to obtain solid-gas equilibrium even in a similar metal enclosure. Thus reproducibility of results is lost. Experimental Procedure The experimental procedure was much the same as that originally developed by Udin, Shaler, and Wulff with a few modifications and improvements. For greater accuracy in strain measurements, knots gave way to cut gage marks as shown in Fig. 1. These were made with a hand-driven lathe in which razor blades serv'ed as cutting tools. Also a more precise cathetometer with a screw accurate to 0.00015 cm was used. The tests were conducted in an atmosphere of purified .helium rather than in vacuum in order to avoid possible evaporation difficulties. Five mil wire of high purity gold (99.98 pct) was used. After cutting in the gage marks, each wire of a series of about 12 was differently loaded by welding a gold ball to one end. This was done by dipping the end of the wire in a cooling gold droplet, previously melted on a charcoal block with a No. 2 acetylene torch. The other end of the wire was strung through a hole in a gold lid and twisted over the edge to hold the wires fixed and in suspension from the lid. The lid and mounted wires were then dipped in pure ethyl alcohol to dissolve any skin oils and dirt on the surface of the wires due to handling. Finally the lid was put in place on an alundum crucible lined with gold so that the wires hung freely within the gold-lined chamber. This whole assembly was next heated in a quartz nichrome wound tube furnace and heated for a few minutes at 600°C to soften the wires. After this anneal the wires were easily straightened with tweezers. The wire assembly was finally annealed 10" to 25°C above the subsequent test temperature for 2 hr. This treatment allowed the grains to grow to equilibrium size and shape. After the anneal, the lid was mounted in front of the cathetometer. The gage length was measured by sighting the 40 power microscope on the upper lip of the lower gage mark for the first reading, then traveling up to the lower lip of the upper gage mark for the final reading. This procedure was repeated four times to give an average gage length value. In this manner the annealed gage length and the final gage length could be measured to determine the strains. During all measurements, grain counts were made.

Jan 1, 1952

By Mark Malamphy

THE occurrence of outcrops of bituminous schists and sandstones impregnated with heavy asphaltic petroleum first directed attention to the Sao Pedro area as a possible source of commercial production of petroleum. Since 1920, more than 20 wells have been drilled in this area. The discovery of oil shows and small quantities of natural gas in some of the early wells led to the continuation of drilling in the hope that more important findings would result. During the early part of 1934, detailed magnetometer observations were made in this area, and a con-siderable number of torsion balance stations were occupied. The results of these geophysical observations help considerably to clarify the structure of the area and the very considerable amount of geologic information available makes possible a much more exact interpretation of geo-physical anomalies. In presenting the results of these observations, and interpretation of the geophysical data, certain actual case problems are included; i.e., geophysical anomalies due to anomalous masses of which the forms and positions are more or less known. Although anomalies due to igneous intrusions are probably more important to geophysicists in Brazil than in other countries, these data have a certain interest for all geophysicists, particularly because they were obtained in the south magnetic hemisphere, where the lines of magnetic force are directed upward, and in a region of moderately low inclination. This is considered as a geological-geophysical problem, and only passing mention will be given to the petroleum possibilities of the area.

Jan 1, 1936

By L. G. Graper, E. L. Ramsey

The present program of increased production of armament and lend-lease material for mechanized war has created a problem for the shops that must do the machining. They have naturally turned to the steel producers to provide them with a steel that can be accurately machined with the greatest possible speed. The adding of sulphur to steel as an aid to machinability has long been practiced; however, it may cause red shortness in rolling and may result in billets with seams and cracks, which must be removed before rolling can be continued. This conditioning of billets slows down production and adds to the cost of making steel. Experience with various grades of sulphur steel made to different specifications has shown that Bessemer sulphur steels roll better than similar grades made in the open hearth, and also that low-carbon steels that are open or semikilled as tapped roll better than completely deoxidized or killed steels. This has led to the belief that oxygen plays an important part in the rolling qualities of sulphur-bearing steels. It is generally held that the red shortness of sulphur steels is due to the low melting point of the sulphide compounds that separate out at the grain boundaries when the steel solidifies. At the rolling temperature of steel these sulphide compounds melt and cause cracking. Adding Sulphur as a Sulphite These difficulties can be avoided if sulphur is introduced into the stecl by means of an anhydrous sulphite, such as sodium sulphite or sodium bisulphite, which—upon decomposition—forms sulphur dioxide. It is assumed that, in this case, the oxygen of the sulphur dioxide forms part of the sulphide inclusions in the steel, and raises their solidification temperature enough so that the formation in the steel of a low-melting eutectic is prevented. The result is the prevention of hot shortness and a more uniform distribution of inclusions. Fig. I shows photomicrographs of steels made with sulphur, while Fig. 2 illustrates the structure of steels made with sodium bisulphite. These samples were cut from the steels as cast—that is, before rolling— and were polished and lightly etched to bring out the grain boundaries. Fig. I shows that sulphide inclusions segregate more or less at the grain boundaries, and it can be seen how the continuity of these low-melting inclusions would cause red shortness. Fig. 2 shows that the sulphide inclusions arc more or less uniformly distributed throughout the matrix. This arrangement of inclusions has no apparent effect on the rolling qualities of a steel. This statement has been substantiated by the observation of the rolling of over 6000 tons of steel made with a sulphite addition. Results As stated before, the sulphur dioxide is added to steel by means of the decomposi- 27

Jan 1, 1942

By L. G. Graper, E. L. Ramsey

The present program of increased production of armament and lend-lease material for mechanized war has created a problem for the shops that must do the machining. They have naturally turned to the steel producers to provide them with a steel that can be accurately machined with the greatest possible speed. The adding of sulphur to steel as an aid to machinability has long been practiced; however, it may cause red shortness in rolling and may result in billets with seams and cracks, which must be removed before rolling can be continued. This conditioning of billets slows down production and adds to the cost of making steel. Experience with various grades of sulphur steel made to different specifications has shown that Bessemer sulphur steels roll better than similar grades made in the open hearth, and also that low-carbon steels that are open or semikilled as tapped roll better than completely deoxidized or killed steels. This has led to the belief that oxygen plays an important part in the rolling qualities of sulphur-bearing steels. It is generally held that the red shortness of sulphur steels is due to the low melting point of the sulphide compounds that separate out at the grain boundaries when the steel solidifies. At the rolling temperature of steel these sulphide compounds melt and cause cracking. Adding Sulphur as a Sulphite These difficulties can be avoided if sulphur is introduced into the stecl by means of an anhydrous sulphite, such as sodium sulphite or sodium bisulphite, which—upon decomposition—forms sulphur dioxide. It is assumed that, in this case, the oxygen of the sulphur dioxide forms part of the sulphide inclusions in the steel, and raises their solidification temperature enough so that the formation in the steel of a low-melting eutectic is prevented. The result is the prevention of hot shortness and a more uniform distribution of inclusions. Fig. I shows photomicrographs of steels made with sulphur, while Fig. 2 illustrates the structure of steels made with sodium bisulphite. These samples were cut from the steels as cast—that is, before rolling— and were polished and lightly etched to bring out the grain boundaries. Fig. I shows that sulphide inclusions segregate more or less at the grain boundaries, and it can be seen how the continuity of these low-melting inclusions would cause red shortness. Fig. 2 shows that the sulphide inclusions arc more or less uniformly distributed throughout the matrix. This arrangement of inclusions has no apparent effect on the rolling qualities of a steel. This statement has been substantiated by the observation of the rolling of over 6000 tons of steel made with a sulphite addition. Results As stated before, the sulphur dioxide is added to steel by means of the decomposi- 27

Jan 1, 1942

By L. G. Graper, E. L. Ramsey

THE present program of increased production of armament and lend-lease material for mechanized war has created a problem for the shops that must do the machining. They have naturally turned to the steel producers to provide them with a steel that can be accurately machined with the greatest possible speed. The adding of sulphur to steel as an aid to machinability has long been practiced; however, it may cause red shortness in rolling and may result in billets with seams and cracks, which must be removed before rolling can be continued. This conditioning of billets slows down production and' adds to the cost of making steel. Experience with various grades of sulphur steel made to different specifications has shown that Bessemer sulphur steels roll better than similar grades made in the open hearth, and also that low-carbon steels that are open or semikilled .as tapped roll better than completely deoxidized or killed steels. This has led to the belief that oxygen plays an important part in the rolling qualities of sulphur-bearing steels. It is generally held that the red shortness of sulphur steels is due to the low melting point of the sulphide compounds that separate out at the grain boundaries when the steel solidifies. At the rolling temperature of steel these sulphide compounds melt and cause cracking. ADDING SULPHUR AS A SULPHITE These difficulties can be avoided if sulphur is introduced into the steel by means of an anhydrous sulphite, such as sodium sulphite or sodium bisulphite, which-upon decomposition-forms sulphur dioxide. It is assumed that, in this case, the oxygen of the sulphur dioxide forms part of the sulphide inclusions in the steel, and raises their solidification temperature enough so that the formation in the steel of a low-melting eutectic is prevented. The result is the prevention of hot shortness and a more uniform distribution of inclusions. Fig. I shows photomicrographs of steels made with sulphur, while Fig. 2 illustrates the structure of steels made with sodium . bisulphite. These samples were cut from the steels as cast-that is, before rollingand were polished and lightly etched to bring out the grain boundaries. Fig. I shows that sulphide -inclusions segregate more or less at the grain boundaries, and it can be seen how the continuity of these low-melting inclusions would cause red shortness. Fig. z shows that the sulphide inclusions are more or less uniformly distributed throughout the matrix. This arrangement of inclusions has no apparent effect on the rolling qualities of a steel. This statement has been substantiated by the observation of the rolling of over 6000 tons of steel made with a sulphite addition. RESULTS As stated before, the sulphur dioxide-is added to steel by means of the decomposi-

Jan 1, 1942

By J. S. Crump, H. L. Stone

Laboratory studies have indicated that displacement of oil from a reservoir by means of a condensing gas drive results in extremely high oil recovery, approaching 100 per cent under the most favorable circumstances. A condensing gas drive is defined as a gas drive in which the gas utilized is appreciably soluble in the oil it is displacing. The laboratory studies consisted of a number of gas drive displacement experiments, all using a horizontal, sand-packed, steel tube as the laboratory reservoir. The experimental results indicate that the more soluble a gas is in the oil to he displaced, the more efficient that gar is as a displacing fluid. Experiments were conducted utilizing both a light, volatile crude and a heavy, asphalt crude as the in-place oil. In both cases, oil recovery was appreciably enhanced by solubility of the displacing gas. It is believed that the use of condensing gas drives would result in increased oil recovery from many reservoirs during either primary or secondary phases of production. INTRODUCTION Since the early days of the oil industry there has been an increasing awareness of the problems of oil recovery. During the last few decades particularly a growing recognition of the problems has led to widespread attempts on the part of the industry to increase oil recovery by improved technology. One method which has been used to increase recovery is the maintenance of reservoir pressure by injection of gas. Part of the beneficial effect resulting from this gas injection was to prevent evolution of the gas dissolved in the reservoir oil, since such evolution would cause the oil to shrink and become more viscous, thereby adversely affecting oil recovery. In most instances, the gas injected was predomillantly methane, and so the possibility of oil recovery by retrograde vaporization existed. Laboratory investigations of displacement of reservoir oils by methane, carried out at high pressure, have indicated that considerable additional recovery of light oils could be effected by vaporization, but only at the cost of a severe volumetric shrinkage of the residual oil which would cause a decrease in relative permeability to oil in the reservoir. Consequently, recovery of oil by physical displacement would be impaired. The study suggested, therefore, that recovery of oil might be enhanced by injecting into the reservoir a gas known to be appreciably soluble in the oil at reservoir conditions. Swelling of the oil due to solution of gas should result and yield a consequent increase in the relative permeability to oil. The work described in the following sections was, therefore, undertaken to investigate the possibility of increased recovery by this mechanism. Research similar to that reported in this paper has been conducted by The Atlantic Refining Co.1,2,3 In these studies, Whorton, et al, and Slobod, et al, used methane-rich gas to displace oil from model reservoirs. Solubility of the gas was achieved by keeping the reservoir pressure greater than the saturation pressure of the original oil, and the degree of this solubility was varied by operating at different reservoir pressures. Thus the Atlantic project was primarily a study of the effect of reservoir pressure upon oil recovery by gas drive. The objective of the work reported in this paper was to study the effect of gas composition upon oil recovery while holding the reservoir pressure constant. DESCRIPTION OF EXPERIMENTS The discussion of the preceding section suggests that

Jan 1, 1957

By N. B. Pilling, R. E. Bedworth

The corrosion of metals is one problem on which time and thought have been expended for many years. In the effort to avert the destructive action of a hostile environment, attention has been directed almost entirely to the conditions under which most metallic structures are called upon to perform, and the extensive and complicated phenomena attending the corrosive action of atmospheric agencies, acting at the ordinary atmospheric temperatures, have been studied, but there is unanimity of opinion regarding many fundamental facts. One neglected phase is the corrosive action of various gases upon metals exposed to temperatures considerably higher than the atmospheric range, and more especially the attack of atmospheric oxygen upon exposed metallic surfaces. That the problem is difficult is connoted by the practical dominance of industrial electric heating by alloys of one type (nickel-chromium). Proprietary interest may account, in part, for the paucity of information available upon even the most general factors determining the behavior of metals and alloys when exposed to such exacting conditions. The present paper gives some conclusions reached as the result of experimental work, extending over several years, on the mechanism and contributory factors of the high-temperature oxidation of a number of simple unalloyed metals; it is free from experimental detail and proof. High-temperature metallic oxidation may be considered as a phase of metallic corrosion. The scheme outlined below, in which corrosive agent and environment are the principal criteria, is one way of analyzing the several groups of corrosion phenomena. Erosion.—Disintegrating or destructive action by physical causes. Corrosion.—Disintegrating or destructive action by chemical causes. Low-temperature Corrosion.—Solid participating phases essentially immobile: (a) Gaseous agent; (b) liquid agent: action electrolytic and action non-electrolytic. High-temperature Corrosion.—Solid participating phases possess diffusive mobility: (a) Liquid agent; (b) gaseous agent: reducing gases, oxidizing gases. (1) Water; (2) miscellaneous elemental and combined oxygen.

Jan 1, 1923

By R. E. Bedworth, N. B. Pilling

The corrosion of metals is one problem on which time and thought have been expended for many years. In the effort to avert the destructive action of a hostile environment, attention has been directed almost entirely to the conditions under which most metallic structures are called upon to perform, and the extensive and complicated phenomena attending the corrosive action of atmospheric agencies, acting at the ordinary atmospheric temperatures, have been studied, but there is unanimity of opinion regarding many fundamental facts. One neglected phase is the corrosive action of various gases upon metals exposed to temperatures considerably higher than the atmospheric range, and more especially the attack of atmospheric oxygen upon exposed metallic surfaces. That the problem is difficult is connoted by the practical dominance of industrial electric heating by alloys of one type (nickel-chromium). Proprietary interest may account, in part, for the paucity of information available upon even the most general factors determining the behavior of metals and alloys when exposed to such exacting conditions. The present paper gives some conclusions reached as the result of experimental work, extending over several years, on the mechanism and contributory factors of the high-temperature oxidation of a number of simple unalloyed metals; it is free from experimental detail and proof. High-temperature metallic oxidation may be considered as a phase of metallic corrosion. The scheme outlined below, in which corrosive agent and environment are the principal criteria, is one way of analyzing the several groups of corrosion phenomena. Erosion.—Disintegrating or destructive action by physical causes. Corrosion.—Disintegrating or destructive action by chemical causes. Low-temperature Corrosion.—Solid participating phases essentially immobile: (a) Gaseous agent; (b) liquid agent: action electrolytic and action non-electrolytic. High-temperature Corrosion.—Solid participating phases possess diffusive mobility: (a) Liquid agent; (b) gaseous agent: reducing gases, oxidizing gases. (1) Water; (2) miscellaneous elemental and combined oxygen.

Jan 1, 1923

A new $18-million hydrometallurgical ore treatment facility for the recovery of molybdenum oxide was dedicated at Climax, Colo., on November 19 by Climax Molybdenum Co., division of AMAX. The Company has been producing molybdenum from molybdenite (MoS2) ores since 1918. Now oxide values, formerly lost in the sulfide flotation plant tailing are to be processed to yield about 3 million Ib per year of metal. In 1965, Climax produced about 50% of world molybdenum from sulfide ore. This ore is mined at the rate of 42,000 tpd. The annual production of concentrate is 100 million lb containing 90% to 92% MoS2, or about 50 million lb of metal. As only a relatively small portion of the total Climax production is sufficiently enriched in oxide molybdenum to process through the new plant, 5700 tpd of selected ore containing 1.5 lb of Mo per ton is now treated by the new process.

Jan 12, 1966

THE second part of the mould for making guns is the core. Without this the space could not be made where the powder is to be and through which the ball, impelled by the fire, can pass and take flight. To make this it is necessary to take two things into consideration, because they are very important. One is what you are to make it on so that it may be supported and kept true. The other is what composition of clay will stand up during casting and yet not be very difficult to extract from the body of the finished gun. For the first, it is found that only an iron spindle of a suitable thickness is able to support the weight of the clay without bending under the heat of the fire or wobbling as it is turned on its journals or when handled. This should be a braccio or more longer than the mould of the gun and worked exactly round, straight, and well tapered like a spindle; above all every one of its joints should be well secured and solid. At the upper end a per-orated heel should be made, and lower down, exactly at the point corresponding to the length of the mould, are one or two other holes through which the little crossbars can be passed that fasten the core to the outer mould and also serve for constructing the disc. Now this iron is to be arranged on two trestles, pivoted so that it may turn truly when rotated. In order that it may not run up and down, make a little iron fork which engages a notch made with a file at the foot, and another at the head. After this, you must prepare clay for the core which is well made and tenacious ,enough not to crack. Fint take care that there are no pebbles in it and that it is composed of a small amount of cloth clippings and much sifted horse dung and some washed and clean wash ashes so that it may be of a tender and crumbly consistency in order that it may later be more easily extracted from the space inside the gun. In the same way, in order that you may be able to take out the iron piece at the same time, first cover it with ashes, and then wrap it all over with a rope of ordinary thickness, leaving a dito of the iron uncovered in every palmo length. [86] Alternatively, you may cover it all very tightly with hemp tow in the same way after it has been covered with ashes. Or heat your iron considerably and then cover it all to the thickness of a good cord with wash ashes or powdered charcoal that has been made into a paste with a little

Jan 1, 1942

By C. Wachmann

The theory presented ill this paper makes possible examination of the phenomenological aspect of secondary oil recovery by alcohol flooding. Limitutions of the theory are contingent on three primary assumptions: (1) chemical equilibrium, (2) no fingering, and (5) no dispersion. The second assumption implies one-dimensional flow. In a geometric sense the theory extends the Buckley-Leverett construction to systems of two slightly miscible fluids and to systems of three components. This is made possible by considering single-phase fluids to be made up two phases, namely of an excess of one phase and a negative amount of the other phase. The procedure is discussed in the paper. The theory also permits direct determination of the relationship between the aqueous phase saturation and the concentration of water in the aqueous phase in a zone of variable composition. The velocity of planes of constant water concentration and of constant saturation can be computted likewise and the existence of saturation discontinuities inferred. Consequently the behavior of such a Zone, which may exist at some time between a displaced and a displacing fluid, May be determined. mathematical details are given in Appendices. Problems of experimental verification are pointed out on the basis of a supporting experiment. Implications of the theory and effects of violations of primary assumptions are discussed briefly. The major conclusion is that, if the primary assumptions are met, with pure alcohol and alcohol-rich .slugs piston-like displacement of oil and water is possible. INTRODUCTION The recovery of oil from porous media by alcohol displacement has been studied for several years. Extensive experimental investigations into alcohol flooding have been carried out in the laboratory although little has been done in the field. A large amount of practical information is available, the extent being indicated by the first three papers cited 1-3 and their respecrive bibliographies. This has permitted the Formulation of inferential theories. A more analytical approach in which theories are developed primarily by reasoning from known physical principles and relationships has, however, lagged behind. In fact, an analytically derived theory of alcohol displacement has not been available. The theory presented in this paper on oil and water displacement by alcohol from a porous medium is a result of the analytical approach. The theory is idealized, as certain assumptions had to be made to make the mathematics tractable and reduce complexity of argument. In particular, major assuptions concerning conditions of equilibrium, interfacial stability, longitudinal mixing, etc., led to the exclusion of fingering, for example, from all considerations. In many laboratory experiments reported in the literature fingering could not be avoided. There is, therefore, disagreement between theories based on experimental evidence available and the analytically derived theory presented here. This theory presented is based on known physical data and makes use of the Buckley-Leverett construction and its suggested extension. The mathematical derivation of the theory is given in Appendices. Three examples relevant to alcohol displacement are discussed to explain the use of this theory: (1) system of two immiscible fluids (the Buckley-Leverett case); (2) system of two slightly miscible fluids involving an extension of the Buckley-Leverett construction; and (3) system of three components, including injection of pure alcohol or alcohol-rich fluid as a special case, which involves a more general extension of the Buckley-Leverett construction. In these discussions strict assumptions were made to impose equilibrium conditions and exclude mixing and fingering. Effects of relaxing these assumptions and consequent extensions of the theory are indicated. The complexity of the alcohol displacement process makes experimental verification of the theory essential. Some relevant evidence is offered in this paper.

Jan 1, 1965

By Willard P. Ward

SOME TIME in the year 1874 or 1875, I conceived the idea that spiegeleisen might be made -in a blast furnace from ores that were not carbonates, and which did not contain both manganese and iron in the same ore. Up to this time, such ores had formed the basis of all the spiegel that had been produced; and all the ferromanganese that was on the market before 1875 was made in crucibles, and cost about 00 per ton, for 80 per cent. Mn. I consulted the great steel metallurgist of the day, Alexander Holley, who listened attentively to what I had to say, and told me he did not think my plan was practical, so I abandoned it for the time being. But I was so stubborn that I could not get the notion out of my head. It seemed to me that a good metallurgist should be able to work the thing out in some way. I had already had some experience in smelting refractory lead ores in Utah, and was young and not lacking in self confidence, so after waiting a bit, I got Anton Eilers, the best all-around metallurgist I knew, and J. H. Bramwell, the best iron blast-furnace man I knew, both intimate friends of -mine, to come to my place in Bartow County, Georgia, and look over things. They remained for several days, and made all the examination they thought necessary; and they also advised me to give up the project, and either to keep the furnace running on car-wheel iron or to blow it out. After my talk with Holley, I improved my plant in several ways. I closed the top of the furnace, put in a hot-blast stove, a steam boiler and a Weimer blowing-engine which gave me blast enough, at a pressure high enough for all the requirements of, the furnace, and which I could bring up to a temperature of 600° to 700° F.

Jan 1, 1921

By J. D. Miller, P. J. McDonough, H. Q. Portillo

Previous investigations have demonstrated the catalytic effect of silver additions in the ferric sulfate leaching of chalcopyrite [ ] The enhanced rate of leaching was found to be due to the formation of an intermediate Ag S film which forms on the Cures2 surface by an exchange reaction Under these conditions, unlike the uncatalysed ferric sulfate leach, the elemental sulfur forms a nonprotective reaction product on the Ag S crystallites As a result, the rate appears to become limited by an intermediate electrochemical reaction in {he Ag2S film rather than by transport through the elemental sulfur reaction product [ ] The reaction rate was found to have a complex dependence on the Ag+, Fe++ and Fe+3 concentrations, but independent of the Cu concentration Electrochemical measurements with a Ag,S-coated chalcopyrite electrode provide further information regarding the nature of the reaction mechanism The kinetics of the rate limiting, intermediate electrochemical reaction are analyzed in terms of the Butler-Volmer equation

Jan 1, 1981

By H. Soto, I. Iwasaki

Primary amines are strong collectors of apatite and they can selectively float sedimentary phosphates from calcareous ores. However, secondary and tertiary amines and trimethyl ammonium salts are ineffective. Kerosene reduces the collector requirements became hydrocarbon is co-adsorbed along with the amine on the mineral surface. The heats of reaction of aminium ions with such anions as phosphate, carbonate, and sulfate were measured in a microcalorimeter. They are discmsed in terms of the solubility of the precipitates formed and their relationship with the adsorption mechanism of primary amines on phosphate minerab. Experimental evidence supports a view that primary amines are adsorbed through chemical interaction between the aminium and phosphate ions at the mineral surface.

Jan 1, 1986

By John V. Beall

There were no easily identifiable tourists. Everybody carried attaché cases and sported the buttoned-down look in dress. They were all there at the Hotel Indonesia to make a deal. But deals don't come quickly over there and those that staved and persevered became bored. They clung to the air conditioning of the Hotel and sought hobbies to while away the weeks-and even months. It is not an easy life but it can pay off fog sonic company. The government officials are neither stupid nor lazy. They are new at their jobs. Many are ex-army men and they know they must learn before they can enter into a contract with confidence. So they take time, and time is on their side.

Jan 1, 1970