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By P. E. Demmler

PHOSPHORUS combines with copper in various proportions, forming true alloys, some of which are of commercial importance. These materials find wide application as deoxidizers and as a means of introducing phosphorus into other alloys, as in phosphor-bronze. Phosphor-coppers containing 10 and 15 per cent. of phosphorus are the commercial grades that are most generally offered. Each has certain advantages when used in making other alloys. The 10 per cent. grade of phosphor-copper has an advantage over the 15 per cent. in that it has a much lower melting point and can be prepared by certain methods with a much lower loss in phosphorus. The 15 per cent. grade has the advantage of lower freight rates per unit of phosphorus and, by the method to be described, a uniform product can be prepared with practically no loss of phosphorus. Alloys of copper and phosphorus containing any desired percentage of phosphorus lower than 15 per cent. can be prepared by melting together the requisite amounts of copper and 15 per cent. phosphor-copper. Processes for making phosphor-copper may be divided into two classes as follows: (1) Those depending on the smelting of phosphate rock or superphosphate of calcium with copper or copper-bearing materials, and coal or other carbonaceous material; (2) those depending on the direct combination of metallic copper and elemental phosphorus. A number of formulas for preparing phosphor-copper according to the first method have been published. The Metal, Industry' gives-the following: Superphosphate of calcium, 60 lb.; granulated copper, 301b.; finely powdered coal, 10 lb. Similar formulas are given by Brannt2 and others, and detail 'variations are covered by patents, such as those of L A Jeffs3 and H A Webster.4

Jan 8, 1920

E. C. Pechin, Buchanan, Va.: I am sorry to see the table appended to Mr. Chase's excellent paper. In the discussion at the same meeting, on "Notes on a Southern Coal-Washing Plant," Prof. Phillips very properly says: " There is no use in giving an analysis as representing a coal when it does not do so. It gives a wrong impression of the conditions under which business is conducted." The same may be said about ores. I have no personal knowledge of the ores in many of the localities given in Mr. Chase's table; but if these are to be judged by what is positively known of the Cranberry ores, the analyses are grossly misleading. The furnace-shipments from Cranberry have rarely reached 44 per cent. of iron, and any such percentage as 58 or 66 or 68 can only have come from hand-picked specimens. Indeed, with any such percentages, Mr. Chase's paper would have been superfluous, because concentration would be unnecessary. Besides, the paper itself (page 553) gives the fact that the Cranberry average is 42 to 43 per cent. Why should a table be appended, contradicting this statement of the text ? Let us always have the exact conditions under which business may be conducted. "Boom" and business analyses are widely different.

Jan 1, 1896

By J. M. Hartman

ONE of the most important subjects to the blast-furnace engineer is a thorough knowledge of the conditions affecting the temperature in the different portions of the furnace. All efforts to decrease the consumption of fuel and improve the working of the furnace must be based upon it, and I may, therefore, be permitted to place before you the results of my observations, and detail the conclusions to which they have led me. Tracing the thermic conditions from below upwards we have at the bottom of a blast furnace making No. 3 iron a temperature of 2900' F., which increases slightly to a point a little below the tuyeres. In the immediate vicinity of the tuyeres the temperature is somewhat lower, owing to the entering blast; but a short distance above the tuyeres, where all the oxygen of the blast has been converted into carbonic acid, the highest temperature in the furnace must be attained. This carbonic acid is, however, almost as soon as formed, converted by the glowing coal into carbonic oxide, a process which absorb, heat, reduces the temperature, and provides the active agent for the reduction of the iron ores. In its ascent the hot carbonic oxide gradually parts with its heat, first melting the descending iron and earthy materials, which drop down to the hearth of the furnace. The limit of this zone of fusion is rather sharply defined, and the temperature above this zone suddenly decreases. In its further ascent the hot gas drives off the carbonic acid from the limestone, which causes a further absorption of heat, and finally the gas escapes at the top, at a ternperature of about 250' F. if the furnace is working well. These changes of temperature I have attempted to represent graphically,

Jan 1, 1880

By Frederick Clapp

ALTHOUGH many oil fields have been, and still are being, discovered in Oklahoma, the geology and structure of most of them have not become familiar to the general public because of the delay in securing government geological surveys and the reluctance of oil companies and other interested parties to give out their "inside information." Therefore, until official surveys are available, it behooves us to publish geological results as soon as possible. Fortunately the writer has been authorized by the Cement Field Oil Co. to publish his data on the Cement field, Caddo County at this time. LOCALITY AND DESCRIPTION The Cement field is situated in the part of Oklahoma known generally, until recently, as "Healdton fields," and lies 60 mi. (96 km.) northwest of the Healdton field proper. Like the Healdton field, it forms an approximate ellipse, trending northwest and southeast through the village of Cement on the St. Louis-San Francisco Railroad, on which it is reached in 2 ½ hours from Oklahoma City. In its geological structure, the field constitutes an anticline over 13 mi. (21 km.) long and from 1 to 3 mi. wide; the point of greatest width being not far from its intersection by the above-named railroad. The major axis trends north 75° west from the village of Cement; but eastward appears deflected (if field interpretations are correct) to about south. 45° east. About 5 mi. south lies an approximately parallel syncline, which may be conveniently called the Cyril syncline, the south and west boundaries of which may be distant many miles, but forming a closed basin', south of the Cement anticline. The position of the offsetting synclinal axis, which is believed to lie north and east of Cement, has not been discovered.

Jan 2, 1920

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 J. M. Hartman

ONE of the most important subjects to the blast-furnace engineer is a thorough knowledge of the conditions affecting the temperature in the different portions of the furnace. All efforts to decrease the consumption of fuel and improve the working of the furnace must be based upon it, and I may, therefore, be permitted to place before you the results of my observations, and detail the conclusions to which they have led me. Tracing the thermic conditions from below upwards we have at the bottom of a blast furnace making No. 3 iron a temperature of 2900° F., which increases slightly to a point a little below the tuyeres. In the immediate vicinity of the tuyeres the temperature is somewhat lower, owing to the entering blast ; but a short distance above the tuyeres, where all the oxygen of the blast has been converted into carbonic acid, the highest temperature in the furnace must be attained. This carbonic acid is, however, almost as soon as formed, converted by the glowing coal into carbonic oxide, a process which absorbs heat, reduces the temperature, and provides the active agent for the reduction of the iron ores. In its ascent the hot carbonic oxide gradually parts with its heat, first melting the descending iron and earthy materials, which drop down to the hearth of the furnace. The limit of this zone of fusion is rather sharply defined, and the temperature above this zone suddenly decreases. In its further ascent the hot gas drives off the carbonic acid from the limestone, which causes a further absorption of heat, and finally the gas escapes at the top, at a temperature of about 250° F. if the furnace is working well. These changes of temperature 1 have attempted to represent graphically,

Jan 1, 1880

By J. W. Leonard, B. A. Donahue

A method is described for incorporating coal petrography into mining and preparation plant quality control based on conventional analyses. Complete analyses are made of each of the uniform and relatively distinct petrographic bands in a coal face. With this information it is possible to develop petrographic standardization curves. These curves permit diverse coal characteristics to be rapidly monitored by application of a few standard coal tests. Single seam quality control is discussed in this paper. Inquiries continue to be made about coal petrography, and specifically, about whether coal petrography should be applied more extensively in the coal industry. Coal petrography is the study of the distinct physical, optical, and chemical increments which make up the organic rock mixture which we know as coal. Petrography can be applied by any coal company or at any coal mine where conventional coal analytical facilities are available and where additional resources can be allocated for an increased number of determinations. This first paper of a two part series includes (1) a proposed conventional approach to single seam petrography based on the development of petrographic standardization graphs and (2) some informative and supplemental interrelationships involving coal characteristics developed as a result of this research. In the second part of this series, to be published at a later date, those petrographic characteristics of bands taken from many different coal seams located over wide geographic areas which can be closely related to each other will be considered. These findings will be examined looking toward the development of a comprehensive, conventional approach to coal petrography which can be used as a common basis for multi-rank petrographic standardization graphs. Implicit to the understanding of coal petrography is the well established fact1,2 that the individual analyses of distinct petrographic bands often differ widely from the average analysis which is used to characterize a whole coal seam. In fact, a distinct and minor banded increment of coal in a high volatile seam may actually be a medium or low volatile coal with an analysis similar to the average analyses of seams located in distant coal fields. During the mining of coal, much degradation is caused which tends to randomly scatter coal bands. The degraded, scattered, and physically separated constituents of distinct petrographic bands are processed side by side in the coal preparation plant as distinct petrographic fractions with particles grouped according to a narrow size range (which derives in part from common hardness), specific gravity, and-or surface chemistry. Tile data obtained from numerous analyses made on each of the bands of any given coal seam, although diverse, can be readily interrelated. Indeed, these interrelationships can be developed into a series of nomographs or petrographic standardization graphs to serve as a basis for developing a conventional petrographic* program. Thus, by analyzing one property (for example, ash) of a selected petrographic fraction collected or separated from the flow of coal in a preparation plant, it should be possible to estimate the other physical, chemical, and thermal properties of this fraction by referring to the petrographic standardization graphs. It follows that any or all petrographic fractions in the total coal flow originating from a single coal seam can be rapidly monitored for many properties on the basis of a single analysis run on each fraction. In recent years coal petrographic research has concentrated heavily on that phase of this work which involves microscopic reflectance measurements made at many minute and selected points on a coal briquette surface.3,4 Thus, the percentage of the total number of reflectance measurements that fall into each of a consecutive series of arbitrarily chosen reflectance classes are used to characterize coal. This procedure is analagous to using the face of a coal briquette to represent the reflectance characteristics present at the face of a coal seam. Moreover, by analyzing petrographic fractions of known and uniform optical properties it is possible to closely relate reflectance to other coal characteristics. For example, reflectance has long been known to be related to such

Jan 1, 1968

By B. E. Morgan, C. K. Dumbauld

The need for a low-strength cementing composition for use in well cementing is reviewed and results are presented of laboratory and experimental field tests of a modified cement having a controlled ultimate tensile strength of approximately 200 psi. The modified cementing composition may he prepared from either high early strength or normal portland cements by the addition of bentonite clay and a suitable agent for dispersing and controlling the set of the slurry. Substitution of the modified cement for conventional slow-set cements may give better completion results in many wells because the modified cementing composition has lower set strength, lower slurry density, and greater slurry stability than conventional cement slurrieh. The lower ultimate strength allows greater penetration with less shattering of the set cement when perforating casing and cement. The lower elurry density allows the placement of longer columns of cement slurry, and the greater slurry stability reduces the possibility of having an uncemented section caused by the settling of cement particles before the cement set.. INTRODUCTION High strength lias always been one of the accepted criteria of a good cement. During the early use of portland cement in well cementing. emphasis was placed upon securing cements with higher strengths. In 1931, Barkis' reported that, "Normal oil well cements have been improved to develop greater strengths and uniformity of product, which has aided in producing successful jobs in cementing the deeper strings." As long as most wells were completed by the open-hole method. the use of cements having high strengths seemed desirable, and there was no objection raised against high-strength cementing compositions. For a number of years. how-ever, the industry has been completing a large numher of wells by setting and cementing casing through productive horizons and then obtaining production by gun-perforating the section of casing opposite the desired interval. Although this method has been generally successful, difficulties have been experienced in some cases in completing or recompleting wells because of apparent lack of adequate penetration by the bullets through the casing and surrounding sheath of cement and into producing formation. In addition to the penetration trouble: there have been indications that fracturing and shattering of the set cement by perforating might he a contributing factor in causing the failure of some jobs to exclude water or gas from oil producing zones. The possibility that cements having high set strengths were contributing to til difficully ill obtaining satihfartory perforating results has re. ceived attention during recent years. Gun perforating tests conducted in 1944 showed that the depth of bullet penetration into set cement varied with the hardness of the cement, the greater the strength of the cement the less being the penetration. In 1946, Farris2 pointed out that high strength cements were not needed in well cementing, and in 1947, data published by Oliphant and Farris3 showed that set cement was perforated without shattering at approximately 150 psi tensile strength. whereas at approximately 300 psi tensile strength severe cracking and shattering occurred. Oliphant and Farris suggested that wells be perforated at the proper time interval after placement of the cement so that the set cement would have the desired strength. Several difficulties may he encountered in trying to perforate a cement job at the correct time to catch the tensile strength near 150 psi. The rate of strength development of different cements varies considerably. This fact is illustrated by results of tensile strength measurements presented in Fig. 1. These data show that at 175°F the tensile strengths of three conventional slow-set cements varied from 75 to 235 psi at the end of 12 hours. After 24 hours, the tensile strengths varied from 200 to 455 psi. The rate of strength development is affected. also. by the temperature of the forniation, and this adds to the uncertainty of perforating at the rorrect time, since accurate well cementing temperatures may not he known in many cases. Furthermore, in the recomple-tion of wells it is sometimes necessary to perforate cement which has set for a long period and has developed maximum or final strength. In view of the apparent need for a cementing composition having a controlled ultimate strength, an investigation was

Jan 1, 1951

By C. K. Dumbauld, B. E. Morgan

The need for a low-strength cementing composition for use in well cementing is reviewed and results are presented of laboratory and experimental field tests of a modified cement having a controlled ultimate tensile strength of approximately 200 psi. The modified cementing composition may he prepared from either high early strength or normal portland cements by the addition of bentonite clay and a suitable agent for dispersing and controlling the set of the slurry. Substitution of the modified cement for conventional slow-set cements may give better completion results in many wells because the modified cementing composition has lower set strength, lower slurry density, and greater slurry stability than conventional cement slurrieh. The lower ultimate strength allows greater penetration with less shattering of the set cement when perforating casing and cement. The lower elurry density allows the placement of longer columns of cement slurry, and the greater slurry stability reduces the possibility of having an uncemented section caused by the settling of cement particles before the cement set.. INTRODUCTION High strength lias always been one of the accepted criteria of a good cement. During the early use of portland cement in well cementing. emphasis was placed upon securing cements with higher strengths. In 1931, Barkis' reported that, "Normal oil well cements have been improved to develop greater strengths and uniformity of product, which has aided in producing successful jobs in cementing the deeper strings." As long as most wells were completed by the open-hole method. the use of cements having high strengths seemed desirable, and there was no objection raised against high-strength cementing compositions. For a number of years. how-ever, the industry has been completing a large numher of wells by setting and cementing casing through productive horizons and then obtaining production by gun-perforating the section of casing opposite the desired interval. Although this method has been generally successful, difficulties have been experienced in some cases in completing or recompleting wells because of apparent lack of adequate penetration by the bullets through the casing and surrounding sheath of cement and into producing formation. In addition to the penetration trouble: there have been indications that fracturing and shattering of the set cement by perforating might he a contributing factor in causing the failure of some jobs to exclude water or gas from oil producing zones. The possibility that cements having high set strengths were contributing to til difficully ill obtaining satihfartory perforating results has re. ceived attention during recent years. Gun perforating tests conducted in 1944 showed that the depth of bullet penetration into set cement varied with the hardness of the cement, the greater the strength of the cement the less being the penetration. In 1946, Farris2 pointed out that high strength cements were not needed in well cementing, and in 1947, data published by Oliphant and Farris3 showed that set cement was perforated without shattering at approximately 150 psi tensile strength. whereas at approximately 300 psi tensile strength severe cracking and shattering occurred. Oliphant and Farris suggested that wells be perforated at the proper time interval after placement of the cement so that the set cement would have the desired strength. Several difficulties may he encountered in trying to perforate a cement job at the correct time to catch the tensile strength near 150 psi. The rate of strength development of different cements varies considerably. This fact is illustrated by results of tensile strength measurements presented in Fig. 1. These data show that at 175°F the tensile strengths of three conventional slow-set cements varied from 75 to 235 psi at the end of 12 hours. After 24 hours, the tensile strengths varied from 200 to 455 psi. The rate of strength development is affected. also. by the temperature of the forniation, and this adds to the uncertainty of perforating at the rorrect time, since accurate well cementing temperatures may not he known in many cases. Furthermore, in the recomple-tion of wells it is sometimes necessary to perforate cement which has set for a long period and has developed maximum or final strength. In view of the apparent need for a cementing composition having a controlled ultimate strength, an investigation was

Jan 1, 1951

By R. L. Orr, O. D. Sherby, J. E. Dorn

Creep data for pure metals at temperatures above those at which rapid recovery occurs (above about 0.45 the melting temperature) are correlatable by means of the equations and These correlations were applied successfully to data for aluminum, iron, nickel, copper, zinc, platinum, gold, and lead as well as for simple alloys. For a given metal, AH is a constant about equal to the activation energy for self-diffusion. THE early recognition that creep is stimulated by thermal activation prompted numerous investigators', ' to apply the same laws that are valid for the viscous behavior of liquids to analyses of creep data. To a good first approximation these laws are summarized by the equation were i is the creep rate; T, the absolute temperature; R, the gas constant in cal per degree per mol; T, the applied stress; AH, the activation energy in cal per mol; S', a constant dependent on the entropy of activation, the frequency of activation, and the contribution of each activation to the strain; and B', a constant dependent upon the size of the flow unit that is activated. Although Eq. 1 describes the flow of viscous fluids very accurately, its application to the creep of solids has been disappointing. Two reasons for the failure of Eq. 1 for creep are now known: First, the decelerating creep rates during primary creep demand that the internal structures of the metals are changing and that these changes might be reflected by changes in one or more of the three creep parameters S', AH, and B'. Consequently when the conventional methods of evaluating these parameters are employed by comparing the secondary creep rates at a series of temperatures and at a series of stresses, the true effects of temperature and stress are masked because of simultaneous changes in one or more of the creep parameters. Second, as will be illustrated more fully later, three distinctly different types of investigations have shown that the stress term for high temperature creep enters the analysis as and not as t/T. This rather unexpected result points sharply to a significant fundamental difference between the mechanisms for the viscous behavior of fluids and the high temperature creep of metals. More recent extensive investigations",'4 on the creep of high purity aluminum and several of its dilute a solid solutions have shown that where E is the total creep strain; temperature compensated time = for a constant temperature test; t, is the initial stress in a constant load test or the constant true stress in a constant stress test;" and t is the duration of test. • Eq. 2 is valid for either constant stress or constant load tests; but the total creep curve is difierent (i.e. the function, f, is differentl for each test. The fundamental origin of the validity of Eq. 2 is thought to arise from some equivalence of substructures in constant load creep tests at equal values of 0 or E. Both X-ray and metallographic examination revealed that practically identical lattice distortions and subgrain sizes are obtained for the same creep strain under the same load over wide ranges of test temperature.' Furthermore the room temperature tensile properties following equal creep strains at different temperatures under constant loads were also identical, illustrating that identical substructures were indeed obtained.' " A second type of correlation was obtained by differentiating Eq. 2 with respect to time, giving For the secondary creep rate, denoted by i,, But Eq. 2 reveals that 0, is a function of a, alone because the secondary creep rate in a given constant load test is always reached at a fixed value E,". Therefore where is the function that was introduced a number of years ago by Zener and Hollomon." Eq. 4 is not only valid for creep but will permit correlations between constant load creep and tensile data where e, is the rate of tensile straining and (TC is the engineering ultimate tensile strength.

Jan 1, 1955

By E. W. Filer, L. S. Darker

ONE of the primary purposes of this investigation was to determine how far blast-furnace metal and slag depart from equilibrium, particularly with respect to sulphur distribution. In studying the equilibrium between blast-furnace metal and slag, there are two approaches that can be used. One method is to use synthetic slags, as was done by Hatch and Chipman;' the other is to equilibrate the metal and slag from the blast furnace by remelting in the laboratory. In the set of experiments here reported, metal and slag tapped simultaneously from the same blast furnace were used for all the runs. The experiments were divided into two groups: 1—a time series at each of three different temperatures to determine the t.ime required for metal and slag to equilibrate in various respects under the experimental conditions of remelting, and 2—an addition series to determine the effect of additions to the slag on the equilibrium between the metal and slag. An atmosphere of carbon monoxide was used to simulate blastfurnace conditions. The furnace used for this investigation was a vertically mounted tubular Globar type with two concentric porcelain tubes inside the heating element. The control couple was located between the two porcelain tubes. The carbon monoxide atmosphere was introduced through a mercury seal at the bottom of the inner tube. On top, a glass head (with ground joint) provided access for samples and a long outlet tube prevented air from sucking back into the furnace. The charge used was iron 6 g, slag 5 g for the time series, or iron 9 g, slag 7 % g for the addition series. This slag-to-metal ratio of 0.83 approximates the average for blast-furnace practice, which commonly ranges from about 0.6 to 1.1. A crucible of AUC graphite containing the above charge was suspended by a molybdenum wire in the head and, after flush, was lowered to the center of the furnace as shown in Fig. 1. The cylindrical crucible was 2 in. long x % in. OD. The furnace was held within &3"C of the desired temperature for all the runs. The temperature was checked after the end of each run by flushing the inner tube with air and placing a platinum-platinum-10 pct rhodium thermocouple in the position previously occupied by the crucible; the temperature of the majority of the runs was much closer than the deviation specified above. The couple was checked against a standard couple which had been calibrated at the gold and palladium points, and against a Bureau of Standards couple. The carbon monoxide atmosphere was prepared by passing COz over granular graphite at about 1200°C. It was purified by bubbling through a 30 pct aqueous solution of potassium hydroxide and passing through ascarite and phosphorus pentoxide. The train and connections were all glass except for a few butt joints where rubber tubing was used for flexibility. The rate of gas flow was 25 to 40 cc per min. As atmospheric pressure prevailed in the furnace, the pressure of carbon monoxide was only slightly higher than the partial pressure thereof in the bosh and hearth zones of a blast furnace—by virtue of the elevated total pressure therein. Simultaneous samples of blast-furnace metal and slag were taken for these remelting experiments. The composition of each is given in the first line of Table I. There is considerable uncertainty as to the significant temperature in a blast furnace at which to compare experimental results. This uncertainty arises not only from lack of temperature measurements in the furnace, but also from lack of knowledge of the zone where the slag-metal reactions occur. (Do they occur principally at the slag-metal interface in the crucible, or as the metal is descending through the slag, or even higher as slag and metal are splashing over the coke?) The known temperatures are those of the metal at cast, which averages about 2600°F, and of the cast or flush slag, which is usually about 100°F hotter. To bridge this uncertainty, remelting temperatures were chosen as 1400°, 1500" (2732°F), and 1600°C. For the time series the duration of remelt was 1, 2, 4, 8, 17, or 66 hr; crucible and contents were quenched in brine. The addition series were quenched by rapidly transferring the crucible and contents from the furnace to a close-fitting copper "mold." Of incidental interest here is the fact that the slag wet the crucible

Jan 1, 1953

By Norman Brown, J. V. Rinnovatore

It was found that a shear stress applied during the recovery had no effect on the amount of recovery if the stress was less than the instantaneous yield point irrespective of the direction of the stress. Large ajplied stresses during recovery had a marked effect, which depended on the direction of stressing. Single strain reversals at -72°C not only produced the Bausch-inger effect but also increased the flow stress. The increase inflow stress was attributed to vacancies, which have appreciable mobility at -72 °C. THEORIES I-' of recovery suggest that the internal stress field of the dislocations plays an essential role. Most investigations of recovery use time and temperature as the independent variables; however, here stress has been introduced as a variable in two ways: 1) by varying the internal stress field according to the amount of strain prior to recovery and 2) by applying an external stress during recovery. Tannen- baum and Kauzrnann studied the effect of applying a stress during recovery by measuring the change in creep rate after recovery; they found that stresses as high as 95 pct of the creep stress had no effect on recovery. Earlier, Wood and scrutton6 showed that an applied stress during creep increased the rate of poly-gonization. The experiment by Wood involved poly-crystalline aluminum whereas Tannenbaum and Kauzmann used a single crystal of zinc. In this investigation, zinc single crystals were used and deformed in a manner to prevent polygonization. Thus, the main difference between this investigation and that of Tannenbaum and Kauzmann is the use of the stress-strain curve instead of creep rate as the index of recovery. In addition, the applied stress during recovery varied

Jan 1, 1961

By Walter F. Pond, Kendall E. Born

Production of crude oil in Tennessee during 1935 approximated 20,000 bbl., an increase of about 5000 bbl. over 1934. The total production for the state is an estimate, since the only definite figures available are those for Scott and Morgan counties, where 12,377 bbl. were marketed during 1935, an increase of 4305 bbl. over the preceding year. The oil fields of Scott and Morgan counties are near the eastern margin of the Cumberland Plateau where Pennsylvanian sediments rest uncon-formably upon the Mississippian. Near Glenmary, in Scott County, the production is from the middle Mississippian, probably near the top of the St. Louis limestone. Accumulation is due to a low, east-west anticline which has been cut by a fault. This field is now 20 years old and only a few wells are pumped at present. Oil was Struck along Boone Camp Creek in Morgan County in 1924 and there has been small production since that time. The oil comes from the middle of the Fort Payne formation of lower Mississippian age at a depth of 1400 ft. Geologic work in the area has shown that a terrace and porosity conditions in the Fort Payne formation account for the accumulation. The production figures on a number of small producing wells in Clay and Overton counties are not available. As pointed out by Glenn1, the installation of small local skimming or topping plants in the fields has curtailed the shipment of crude oil out of the state and as a result it has been impossible to secure accurate production figures in these counties. The operators, in most cases, are reluctant to give information, and there is no state law requiring them to do so. Based upon information available to the writers, it is believed that between 7000 and 8000 bbl. is a fair estimate of the production in Clay and Overton counties during 1935. More than 500 wells have been drilled in Clay County, the majority of which were drilled east of Cumberland River. Some eight small oil fields have been developed in the county within the past 12 years, a

Jan 1, 1936

By Kendall E. Born, Walter F. Pond

Production of crude oil in Tennessee during 1935 approximated 20,000 bbl., an increase of about 5000 bbl. over 1934. The total production for the state is an estimate, since the only definite figures available are those for Scott and Morgan counties, where 12,377 bbl. were marketed during 1935, an increase of 4305 bbl. over the preceding year. The oil fields of Scott and Morgan counties are near the eastern margin of the Cumberland Plateau where Pennsylvanian sediments rest uncon-formably upon the Mississippian. Near Glenmary, in Scott County, the production is from the middle Mississippian, probably near the top of the St. Louis limestone. Accumulation is due to a low, east-west anticline which has been cut by a fault. This field is now 20 years old and only a few wells are pumped at present. Oil was Struck along Boone Camp Creek in Morgan County in 1924 and there has been small production since that time. The oil comes from the middle of the Fort Payne formation of lower Mississippian age at a depth of 1400 ft. Geologic work in the area has shown that a terrace and porosity conditions in the Fort Payne formation account for the accumulation. The production figures on a number of small producing wells in Clay and Overton counties are not available. As pointed out by Glenn1, the installation of small local skimming or topping plants in the fields has curtailed the shipment of crude oil out of the state and as a result it has been impossible to secure accurate production figures in these counties. The operators, in most cases, are reluctant to give information, and there is no state law requiring them to do so. Based upon information available to the writers, it is believed that between 7000 and 8000 bbl. is a fair estimate of the production in Clay and Overton counties during 1935. More than 500 wells have been drilled in Clay County, the majority of which were drilled east of Cumberland River. Some eight small oil fields have been developed in the county within the past 12 years, a

Jan 1, 1936

By Warren B. Weeks

The development of the relatively deeper fields discovered during 1937 helped build the 1938 production to 18,456,760 bbl., an increase of 6,295,910 bbl., or 51.6 per cent over 1937, and the largest production for south Arkansas since 1930. Schuler and Rodessa accounted for the increased production as well as for over half of the wells drilled in the state. There were 243 holes drilled during 1938, of which 200 were completed as oil or gas wells. Of the 29 wildcat wells completed, 25 were dry, 3 found oil in the Smack-over limestone, while 1 made a small oil well in the Nacatoch sand. This was less than half the number of wildcats drilled the previous year, but nearly twice as many field wells were drilled. The old depth record of 7973 ft. was exceeded twice during the year, with the present record of 8332 feet. Trend of Prospecting The porous "Reynolds" oolite of the Smackover limestone1 has been the object of most of the wildcat prospecting during the past two years. Seismograph work, which brought 22 crews into this area during 1938, was largely pointed toward a study of the structure of this limestone formation. Thirteen dry wildcats have been drilled to this formation and five pools have been opened in it since it was first found to be productive at Snow Hill in the spring of 1936. With the failure of "updip" prospects to produce, activity moved southward and basinward. Success in five instances in Columbia and south Union Counties has spurred activity in this area. Much of the acreage is under lease and half a dozen deep limestone tests are assured for the current year. Fig. 1 shows the location of the principal oil fields in south Arkansas, as well as one or two minor producing areas. The fields are numbered in the order of their discovery. It is shown that most of the recent discoveries are from the deeper formations. Dry wildcats that penetrated

Jan 1, 1939

By Warren B. Weeks

The development of the relatively deeper fields discovered during 1937 helped build the 1938 production to 18,456,760 bbl., an increase of 6,295,910 bbl., or 51.6 per cent over 1937, and the largest production for south Arkansas since 1930. Schuler and Rodessa accounted for the increased production as well as for over half of the wells drilled in the state. There were 243 holes drilled during 1938, of which 200 were completed as oil or gas wells. Of the 29 wildcat wells completed, 25 were dry, 3 found oil in the Smack-over limestone, while 1 made a small oil well in the Nacatoch sand. This was less than half the number of wildcats drilled the previous year, but nearly twice as many field wells were drilled. The old depth record of 7973 ft. was exceeded twice during the year, with the present record of 8332 feet. Trend of Prospecting The porous "Reynolds" oolite of the Smackover limestone1 has been the object of most of the wildcat prospecting during the past two years. Seismograph work, which brought 22 crews into this area during 1938, was largely pointed toward a study of the structure of this limestone formation. Thirteen dry wildcats have been drilled to this formation and five pools have been opened in it since it was first found to be productive at Snow Hill in the spring of 1936. With the failure of "updip" prospects to produce, activity moved southward and basinward. Success in five instances in Columbia and south Union Counties has spurred activity in this area. Much of the acreage is under lease and half a dozen deep limestone tests are assured for the current year. Fig. 1 shows the location of the principal oil fields in south Arkansas, as well as one or two minor producing areas. The fields are numbered in the order of their discovery. It is shown that most of the recent discoveries are from the deeper formations. Dry wildcats that penetrated

Jan 1, 1939

By H. C. Chang, N. J. Grant, A. R. Chaudhuri

During the creep of coarse-grained polycrystalline magnesium at elevated temperatures, a nonbasal type of slip was found to play an important role in the deformation processes. The nonbasal slip traces were examined metallographically in eight specimens (13 grains) and the observed glide plane located stereographically for each grain. The tests were run at 500&apos; and 700°F at stresses of 148 to 786 psi. Based on these measurements and theoretical calculations, the crystallographic elements for nonbasal slip were determined. WHEN a metal deforms by slip, the conventional appearance of the slip bands on the surface of a specimen is that of straight lines. Such is the behavior of the face-centered-cubic metals, as for example, aluminum. The particular slip system on which slip occurs in these metals is governed by the criterion of resolved shear stress. Work on the body-centered-cubic metals a-iron,&apos;. &apos; molybdenum, and columbium4 has shown that the process of slip is somewhat more complicated than the simple gliding of one close-packed plane of atoms over another in a close-packed direction and that it results in the formation of wavy and irregular slip traces on the surface. The recent reviews and experiments of Vogel and Brick and Chen and Mad-din3 show that, for the body-centered-cubic metals, the resolved shear stresses along the planes and the degree of close-packing do not necessarily determine the slip system. Theirs and other investigations indicate that a complete understanding of the slip process in the body-centered-cubic metals is not yet possible. However, one behavior displayed by all these metals is that the slip direction is invariably one of the close-packed directions <11l>. The wavy nature of the slip-band traces has been explained on the basis of cooperative slip by planes sharing this same slip direction.1&apos;3l&apos; It is generally acknowledged that, when the hexagonal-close-packed metal magnesium (axial ratio c/a = 1.624) deforms by slip at room temperature, it does so by basal slip in the close-packed direction <1I%>. This type of slip has the conventional appearance of straight lines and is governed by the critical shear-stress law. Schmid and coworkers" showed that basal slip was operative in the temperature range of —185" to 300°C (—300" to 572°F). Work by Servi, Norton, and Grant6 has shown that, during the creep of coarse-grained aluminum at high temperatures, new slip systems come into operation. The existence of a new high temperature slip system at temperatures greater than 225 °C (437°F) for magnesium was suggested also by Schmid. This was later indicated by Bakarian and Mathewson&apos; to be slip along the pyramidal planes (10i1) in the close-packed direction <11%>.* They * Mention will be made in the text of pyramidal planes and prismatic planes. The pyramidal planes referred to are the type I. order 1 of the form {10il); and the prismatic planes of the type 1 of the form (10i0). For the sake of brevity, they are termed in the teat as pyramidal (10il: and prismatic (10i0) planes, respectively. Where reference is made to the pyramidal plane type 1, order 2 of the form {10i2), they are referred to as the pyramidal planes of the type (10i2:. observed that this kind of slip resulted in irregular markings on the specimen surface. According to them, a possible cause for the appearance of the markings was due to "limited accessory slip on the pyramidal {10i2) planes." Burke and Hibbard," on deforming a single crystal of magnesium at room temperature, found evidence of slip on a pyramidal plane {1011). They explained it as being due to the effect of grip restraints. It is pertinent to note at this point that, although basal slip has received a fair amount of attention, only two specimens have been investigated, that of Bakarian and Mathewson and of Burke and Hibbard, to establish the elements of nonbasal slip in magnesium. During the study of the deformation mechanisms

Jan 1, 1956

By F. V. Lene, E. J. Westerman

The recrystallization behaviors of two extruded and cold-drawn experimental sintered aluminum powder alloys, containing 1.75 and 3.0 pct Al2O3 by weight, were compared with that of extruded and cold-drawn commercially pure alumirzum. The kinetics of recrystallization of the alloys are described semiquantitatively. For the alloy containing 1.75 pct A l203 the rates of nucleation and of growth were also semiquantitatively determined. THE most striking property of aluminum alloys strengthened by a dispersion of Al2O3, the so-called SAP alloys, is their stability at elevated temperatures. One of the manifestations of this stability is their resistance to recrystallization after they have been cold worked. Most of the commercial grades of either the Swiss SAP or of Alcoa&apos;s Aluminum Powder Metallurgy Products have not been recrys-tallized after cold working, even when they are heated for a long time at a temperature near the aluminum melting point. Lenel, however, observed that the dispersion strengthened aluminum alloys with a larger spacing between the oxide particles than that of most commercial grades would recrys-tallize.1 It appeared to be of interest to further investigate the mode and kinetics of recrystallization of these alloys, and to compare their recrystallization behavior with that of commercially pure aluminum. Because homogeneous deformation of these SAP alloys in tension did not provide sufficient cold work to induce recrystallization, they were cold worked by wire drawing; the nonuniformity of this deformation unavoidably complicated the interpretation of the recrystallization studies. EXPERIMENTAL DETAILS Extrusions—Two types of sintered aluminum powder extrusions were used in this study. One type, designated AT-400, was produced from Reynolds atomized aluminum powder consisting of spherical particles averaging 3µ in diam and containing 1.75 wt pct of Al2O3. This powder was very similar to the R3M powder from which extrusions were previously prepared with an average spacing of 0.9µ between oxide particles.2 The second type, designated MD 2100, was produced from Metals Disintegrating Co. flake powder containing 3.0 wt pct of Al2O3, with an average flake thickness of 0.8µ. The average spacing between oxide platelets in MD 2100 extru- sions was 0.45µ.2 Powder compacts of 3/4-in. diam were extruded at 1000°F into 0.097-in. diam (AT-400) and 0.093-in. diam (MD 2100) wires by methods previously described.3 In order to compare the recrystallization behavior of sintered aluminum powder extrusions with that of wrought commercially pure aluminum 3/4 in. rod stock of 1100 F aluminum was extruded at 1000°F into 0.102-in. diam wire. Wire Drawing—Tungsten carbide dies were used for the AT-400 and 1100 F alloys. They had an included angle of about 15 deg and reduced the wire area approximately 7 pct per pass. Steel dies with an included angle of 11 to 13 deg and an average reduction per pass of 10 pct were used for drawing the MD 2100 alloy, because drawing this alloy through the carbide dies produced overdrawing defects. Heat Treatment—The cold-drawn wires were cut into small samples, and the deformed ends were etched off. The samples were each wrapped tightly in a single layer of aluminum foil, and individually isothermally annealed in a lead bath. Metallography—The modes and kinetics of recrystallization were determined by metallography. Mounted and polished specimens were anodized in a solution of 1.8 pct HBF4;4 examination under polarized light clearly revealed their grain structures. The recrystallized grains were generally much larger than those of the unrecrystallized matrix, and could clearly be distinguished because they alternated between maximum and minimum light reflection when the microscope stage was rotated, while the unrecrystallized matrix had a comparatively homogeneous "salt and pepper" structure. The fractional recrystallized volumes of the dispersion hardened alloy wires were determined by cutting and weighing of recrystallized and total transverse areas on photomicrographs. The recrystallized grains in the 1100 F alloy were too small to be cut out individually; therefore a combination of cutting and lineal analysis was used in this case. RESULTS AND DISCUSSION Modes of Recrystallization—The modes of recrystallization of the three alloys varied widely. In the 1100 F alloy nucleation and growth started in the region midway between the center and the surface;

Jan 1, 1961

By G. A. Vissac

O. R. LYONS *—I wish to thank Mr. Vissac for his compliment. I hope that his paper is not only well received, but that it will serve to bring forth more papers on the subject of thermal drying. One of the primary purposes of the work performed by Battelle for Bituminous Coal Research in investigating the thermal drying of coal was to stimulate other investigators and to get them to contribute their knowledge in the form of papers such as this one. We at Battelle and the personnel of Bituminous Coal Research are very gratified that Mr. Vissac and other persons have responded in this matter of the thermal drying of coal. I wish to state that I think that Mr. Vissac&apos;s paper is a very clear and easily understood description of a method of calculating the design requirements for a screen type drier, and I think that it would be exceedingly valuable to operators and to those who intend to purchase any type of thermal drier and use it in the future, if the manufacturers or operators who have such information for other types of driers would provide the same type of information for the other makes of driers now on the market. 1 also wish to point out—an idea that is new to me, and I know is new to most of the operators of driers in the United States-—the idea of recovering the heat that is normally lost in the coal and in the exhaust gases. This heat is not being recovered at most (of the thermal drying operations in the United States, and the possibility of recovering it should be called to the attention of every single one of those operators. I know many of them have never given any thought to the matter, but they will be interested once they realize the ease with which it could be done and the savings that could be realized. I also wish to compliment Mr. Vissac for presenting the method of analysis that he uses to determine the difficulty of drying any particular coal. It is a very simple method, and yet it seems to me that it should be a very effective, very efficient method for determining the difficulty of drying for his particular problems. C. Y. HEINER*—I do not know that I can add anything very illuminating to what Mr. Vissac has said. I think anything that Mr. Vissac said in regard to coal drying is a contribution because, to my personal knowledge, he has studied the matter carefully for many years and made many valuable contributions. I am not too familiar with coal drying problems in the east, but I know in the west we have not made enough coal drying studies. I think coal operators too often just take the coal as it is and make more or less the best of it. There are relatively few washing plants in the west now, and so the problem has not come to the front as much as it probably will in the future. In this connection, it seems to me that this matter of drying the raw coal, as Mr. Vissac brings up, is an extremely important one. We have not a continuous miner ourselves, yet, but we expect to get some this year, and we think the percentage of fine coal-—that is, minus 3/16 in.—will double. We have about 20 pct minus 3/16 in. in the 8 in. by 0 size now, and we think we will likely have 40 pct, which will have a surface moisture of the order of 8 pct. To wash it satisfactorily, we will have to dry the raw coal first in order to screen it, and after that, I suppose, there will have to be dry cleaning of some sort. We have not really used dry cleaning on fines in the west yet to my knowledge, but it is a matter that has to be faced by the industry, and I am very hopeful that Mr. Vissac&apos;s study will assist us in that connection. W. L. McMORRIS*-In my company we are preparing largely metallurgical coal for a great number of byproduct coke plants. The most outstanding thing to me about the requirements of moisture in the finished product is that there is a different requirement for almost every coke plant. Each operator has a different set of factors on which he establishes his coking costs where they involve moisture. For our corporation operations in Birmingham, my company does not produce the coal, but in Birmingham they are getting away with moistures very much higher than our plant at Clairton, Pa., would tolerate. The moisture that we have to produce for the plants along the lakefront where they are subject to much more severe weather is something else again. We have not tackled heat drying, primarily because our customers do not know what heat drying will do to the coking characteristics of the coal. If the temperature of drying can be held down

Jan 1, 1950

By C. G. Dunn, F. Lionetti

The energy associated with grain boundaries in polycrystalline aggregates is believed to play a major role in grain growth processes and, when growth ceases, to determine the final equilibrium grain boundary angles. Further, the energy of grain boundaries of recrystallization nuclei is a factor in nucleation processes. It is important to know, therefore, how the energy per unit area of a grain boundary, that is, the grain boundary surface tension y, depends on the difference in orientation of the two lattices of the grains producing the boundary. Although the problem is important, surprisingly little has been done toward a quantitative evaluation of the effect of orientation difference on grain boundary energies. C. S. Smith1 recently has discussed this problem and in addition to showing effects of orientation difference on equilibrium angles has shown a variety of interesting effects of surface tension on the appearance of microstructures. Fig 1 and the following relations expressed in Eq 1, which connect equilibrium grain boundary angles and surface tensions, illustrate equilibrium conditions which are believed to hold true in metals. ?l2 _ ?23 _ ?l3 [1] sin ?3 sin ?1 sin ?2 Clearly any two of these surface tensions can be expressed in terms of the third when the equilibrium angles ?1, ?2, and ?3 are known. Applied to the present problem for solid state equilibrium of three grains, the angles ?1,?2 and ?3 must be measured in a plane perpendicular to the line of junction of the three grains. Normally a direct determination of these angles from random microsections is impossible. Consequently Harker and Parker2 and Smith1 (except for some measurements on flat specimens) resorted to a statistical method to determine equilibrium grain boundary angles. Smith reported that grain boundaries meet the surface of a piece of metal nearly perpendicularly. He reported also, in connection with direct angle measurements on flat specimens with grains extending through the thickness, that angles varied appreciably from 120" and concluded that there was a measurable effect of orientation difference on surface tension. Another direct way of determining equilibrium angles and a method adaptable to studying particular configurations, recently suggested by Dunn,³ is to use a three-grain flat specimen with orientations of grains so chosen that the junction line of the three grains will be straight throughout the thickness and perpendicular to the surface of the specimen. Choice of orientations is possible when individual grains of each group can be grown to predetermined orientations through the reorienting and growth of " seed crystals " as described.³ Not only is it possible, for example, to have grains with the same crystallographic plane in the plane of the specimen, but a given orientation difference between two grains can be made a common factor to an unlimited number of three-grain groups while a series of orientation differences is investigated. Any effect of anisotropy of gas-solid surface tension due to grain orientation should be minimized by having all gains oriented the same with regard to crystallographic plane in the plane of the specimen. Another feature of the three-grain group is the notched grain boundaries as shown in Fig 2 for one specimen (S4). The notches serve to anchor the end positions of the grain boundaries (especially at high temperatures) while the central and junction point of the grains moves toward an equilibrium position. Final equilibrium should produce straight grain boundaries if the notches are very narrow and if changes in orientation* of the grain boundary do not alter the surface tension.† If one assumes the straight line condition and no change of surface tension with small changes in grain boundary orientation and finds the equilibrium configuration by a minimization of the grain boundary energy, one obtains the relations given in Eq 1. The approach to straight line boundaries or to minimum energy configurations in specimens containing large grains, such as those used in the present investigation, may be very slow compared with the approach to equilibrium conditions for the grain boundary angles. It may be desirable, as proved to be the case in the present investiga-

Jan 1, 1950