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By Chester Purington

THE AUTHOR hopes that this paper will meet with criticism and debate by fellow members of the Institute rather than with that attitude of passiv-ity and indifference which one is inclined to adopt when considering a field completely foreign to one's own experi-ence. After several years of study of voluminous literature, maps, and statistics, and many personal journeys and field inspections of various parts of Siberia, the conclusion is reached .that the area adjacent to the Stanovoi, Zhugd-Zhur, and Yablonoi ranges as below defined is that which .is most accessible to the western world and will soonest give results from exploration. HISTORY The first incursion of the Russians into Siberia east of the Yenesei River appears to have been in 1632 when the fort of Yakutsk was founded on the middle Lena. The early expeditions were in quest of furs. As the Siberians say, "the sable beckoned" and the post of Anadyr was founded in 1639, two thousand miles further northeast. Thus nineteen years after the Pilgrims landed in Massachusetts, the Russians had established a trading post within 700 miles of what is now the town of Nome, Alaska. Parties of Cossaks penetrated to the shores of the Okotsk1 Sea early in the seventeenth century, but it was not until 1688 that the town of Okotsk was founded. In 1712 a grand project was elaborated at St. Petersburg for building a port at Okotsk, but it came to nothing. Vitus Bering, the Alaska explorer, built ships at Okotsk, and made this his point of depar-ture. It is stated that the iron work used in these ships was brought overland partly from Yakutsk, and partly even from St. Petersburg, 5500 miles away. Accord-ing to report a copper deposit was worked on the river Urak, not far from the coast, and copper was smelted for sheathing the bottoms. Grassgrown mounds con-taining slag and shots of copper were inspected by the writer last summer, at the site of the ancient shipyard.

Jan 11, 1923

By E. S. Bumps, M. Baeyert, W. F. Craig

SOME time ago during a study of impact properties of tempered martensite,1 it was postulated that the consistently good ductility of tempered martensite might be caused by its relatively small and peculiarly shaped ferrite grains. The fer-rite grains of tempered martensite have approximately the same size and shape as the martensite "needles." Thus they form an interlocking mass of needle-shaped grains quite different from equiaxed or lamellar ferrite grain structures. When the common mechanical test methods are applied to steel, variations are often observed in the ductility of specimens that have closely similar hardness and tensile strength values. The ductility so measured appears to be structure dependent. When steel from the same heat has been heat treated to produce different structures with the same hardness, the elongation and reduction of area values from the tensile test and the transition temperature determined by the notched-bar impact test vary according to whether pearlite, tempered martensite, or other structural constituents were produced by the heat treatment. It has been widely recognized that tempered martensite gives a consistently good performance, when tempered to the same hardness as many other structures with which it has been compared. In recent years the isothermal transformation of austenite to specific structural products and the quantitative evaluation of the character of these products with respect to their nature and response to deformation has received considerable attention. The objective of the present study was to pursue somewhat further the dependence of ductility upon structure; specifically, it was desired to ascertain whether ferrite grain structure, including both shape and size of the grains, can account for the consistently good performance of tempered martensite in the notched-bar impact test. It was thought that a simple experiment would indicate whether the ferrite grain structure plays any part in the good ductility exhibited by tempered martensite in contrast to other steel structures with different types of ferrite grains. By determining the impact transition temperature, it was proposed to compare spheroidites having similar carbide particle size and spacing but obtained in such a manner that their ferrite grain structures would be very different. Spheroidite obtained by tempering martensite, with its small, needle-shaped grains, was to be compared with spheroidite from pearlite. If the latter is produced by sub-critical annealing, the ferrite grains correspond to the pearlite colonies. Thus, if the pearlite was not too coarse, the ferrite grains of spheroidite from pearlite are equiaxed in contrast to the needle-shaped grains of spheroidite from martensite. It was thought that the ferrite grain structure of spheroidite from martensite might depend to some extent upon the grain size of the prior austenite. The austenite grain boundaries limit the maximum attainable size of the martensite needles and thus of the ferrite grains in the derived spheroidite. In order to evaluate any possible influence of prior austehite grain size, spheroidites were to be prepared from martensites that had been formed from fine-grain austenite and also from coarsened austenite. As the carbide particle size and distribution were to be essentially alike in the various spheroidites, the difference would be in the ferrite grain size and shape. Thus any marked difference in transition temperature could be attributable to the character of the ferrite grain structure. There are certain considerations in assuming that these spheroidites would be equivalent in all respects except ferrite grain structure, and an attempt was made to take them into account. One of the considerations was the choice of the carbon content of the steel. An approximately eutectoid steel was selected for two reasons. First, the pearlitic structure would contain no proeutectoid ferrite which might complicate the picture by producing a non-uniform ferrite grain structure in the resulting spheroidite. Then, too, the high-carbon content would inhibit ferrite grain growth during the sub-critical treatment. Another factor to be taken into account was the choice of an alloying element to assure a martensitic structure throughout on quenching the impact specimens. Nickel was chosen, because it is a common alloying element and resides in the ferrite both upon its formation from austenite and throughout tempering. The formation of alloy carbides, or even a large solubility of the alloying element in cementite, would have complicated the interpretation by changing the composition of the ferrite .during spheroid-ization. The possibility of temper brittleness was minimized insofar as possible by using a tempering temperature as high as consistent with the 1 pct of nickel in the steel, namely, 1150°F. While it certainly is not claimed that no difference other than ferrite grain structure could exist between the spheroidites, nevertheless, reasonable precaution has been exercised within the limits of steel metallurgy. It is believed that any large difference in transition temperatures would reflect the difference in ferrite grain structure and that relatively good ductility in the spheroidites from mar-

Jan 1, 1951

By Charles E. Lundin, Albert S. Yamamoto

The phase eqrtilibria of the binavy system, Nb-Al, weye established by metallographic, X-ray diffraction, hardness, and thermal-analysis techniques. Three intermediate phases were identijied, Nb3.41, Nb2Al, and NbAl,. The N6,Al and NbAl phases have extensiue ranges of solubility. The maximum solubility of aluminum in niobiuitz is 23.0 i0.5 at. pct (8.0 wt pct) A1 clt 1960" i 10°C. The maximumt solinbility oj niobiunz in alunzinutz is less than 0.3 i0.1 at. pct (1.0 tut pct) fib. The A'h,Al and Nbgl interinediate phases forr peritectically at 1960° 1UcC and 1870" i 1U9C, respectively, zuhereas the NbAl, phase fornts congvuently fio11t the melt at 1605" 10°C. A eutectic reaction oc- The intent of an over-all research program was to develop niobium-aluminide-base coatings for refractory metals since these coatings exhibit useful high- curs at 57.8 i 0.5 at. pct (28.5 wt pet) A1 and 1500" 10°C between NbAl and NbAl3. The aluminum-rich region of the system has a peritectic reaction where liquid reacts with NbAL, to form aluminum solid solution. Structural and lattice -pavarneter data /or the intermediate phases were determined by X-ray diffraction analyses. An unusual transfov?nation having charactevistics of nucleation-growth and martensitic nleclanisils occurs on cooling the niobium solid solution in the region from 18 at. pct (6 wt pct) Al to 23 at. pct (8 wt pct) Al. The transfornzed product on rapid quenchirzg is an acicular NhAl. temperature resistance to oxidation. As a prerequisite, the phase equilibria of the system, Nb-A1, were necessary. A literature survey revealed that the phase-equilibria data reported by various investigators were rather incomplete and conflicting. Therefore a complete determination of the system was undertaken by the authors from 0 to 100 pct of solute addition.' In 1959 Savitskiyz presented a tentative diagram which

Jan 1, 1967

By W. Vickers

Single-point rotating cantilever fatigue tests have been carried out at 550" to 650°C on beryllium produced by a variety of fabrication routes. All the specimens gave similar plots of stress against number of cycles to failure but failure occurred at a lower stress range in the hot-pressed material than in the extruded material. A discontinuity or "kink" appears to exist in the curves and this is considered. A true endurance limit was not evident up to 10 cycles. When Brush hot-pressed warm-extruded beryllium was tested at 600oC a relationship where Nf = number of cycles to failure, ?ep = plastic strain range, and c = constant, was shown to be applicable for values of ?ep > 6.3 x 10-4. Further for this moterial and temperature and for frequencies between 150 and 4500 cycles per min, the variation of number of cycles to failure with frequency obeyed the expression N = Af0.44 where N =number of cycles to failure, f = frequency, and A = constant. Examination of the fracture surfaces indicated that they were generally intergranular and in all cases the higher the stress the more irregular was the fracture. Microexamination has shown that grain boundary cavities and fine intergranular cracks were associated with the fractures. REVERSING or cyclic stresses set up in fuel elements can lead to failure by fatigue. Fatigue stresses may be developed by instability of the fuel element in the coolant flow leading to rattling against the channel wall or fin vibration. Thermal cycling also sets up reversing stresses due to differential expansion of fuel and can. Fatigue resistance is of some importance therefore in the evaluation of canning materials. At the time the work described in this paper was initiated, beryllium was being considered for the can and endcaps of an advanced gas-cooled reactor fuel element. With this in mind, beryllium obtained from different manufacturing routes was tested on single-point rotating cantilever fatigue machines at temperatures the same as those envisaged in the reactor to obtain appropriate fatigue data. The results obtained indicated a discontinuity in the S-N curves coinciding with the yield stress in the specimens. Although in some cases the data is insufficient to warrant a detailed quantitative analysis, a qualitative analysis of this effect was thought to be justified. 1) EXPERIMENTAL DETAILS The materials used are given in Table I together with the production route and available analyses. The specimen shape is shown in Fig. 1. The fatigue specimens were machined slightly oversize, after which they were given a stress-relieving anneal of 1 hr at '750° C in vacuum. This was followed by an etch in sulfuric-phosphoric-chromic acid mixture down to the finished dimensions given in Fig. 1. Etching served to remove the interference colored oxide film formed on the surface during annealing and very small recrystallized surface grains too. The specimen was mounted in the grips of a cantilever machine and rotated inside a furnace controlled at the testing temperature. The specimen was loaded in increments as the speed was increased until the required load was applied at 5000 cycles per min. A revolution counter was used to record the total number of cycles.

Jan 1, 1964

By A. E. Jenkins, L. A. Baker, N. A. Warner

The electromagnetic levitation technique has been successfully applied to rate studies of the de-carburization of liquid Fe-C alloys from 5.5 to zero pct C at 1660°C using gas mixtures containing 1 to 100 pct CO2 with CO or helium as diluents. The rate was shown to be independent of carbon concen -tration in the melt and only slightly affected by total pressure. The results were shown to be consistent with control either wholly or predominantly by gaseous diffusion. As well as avoiding side reactions with the crucible, levitation allowed precise calculation of reaction rates since the geometry of the system was accurately known. It also enabled interpretation using the established mass-transfer correlations for a gas flowing past a single sphere, The existence of gaseous-diffusion control and the extremely high rates of reaction reported for gas flowing past small spheres are of great practical significance in relation to current investigations into the use of spray-refining techniques in continzcous steelmaking. PREVIOUS work on the kinetics of carbon removal from liquid iron has generally involved the use of oxygen as the gaseous oxidant. Investigations have been made on commercial steelmaking furnaces and in addition laboratory-scale experiments have been attempted with a slag phase present. The general lack of agreement and the obvious difficulty in interpreting the results is at least partly due to the complexity of the systems used. This work has been reviewed by carter1 and more recently by Bods-worth2 and ward.3 The gas-liquid metal reactions have also been studied with slag-free melts by the conventional technique of blowing oxygen onto the melt contained in a crucible. The reaction between the oxidant and carbon could be followed by sampling either the melt or the gas phase. Side reactions with the crucible material have precluded direct interpretation of the results. Fujii, 5-7 using O-A mixtures, attempted to correct for the crucible reaction and reported that the reaction between carban and oxygen occurred at the melt surface and was controlled by gaseous diffusion for carbon contents greater than a critical value and by carbon-diffusion control in the metal for carbon contents less than the critical. The critical value was given as approximately 0.15 pct C. However, whereas this was the case for oxygen contents in the gas stream up to 10 pct, between 10 and 20 pct the rate was found to be approximately independent of oxygen content, and Fujii attempted to explain this observation by postulating the presence of an oxide "film".7 Turkdogan et a1.' have studied iron fuming during decarburizing and suggested gaseous-diffusion control of the reaction above a critical carbon concentration, given as approximately 2 pct C. Filippov9-12 reports in a similar manner to Fujii but makes no mention of the crucible reaction with the carbon in the melt, even though this would be expected with the temperature, crucible material (MgO), and carbon contents used. Both CO2 and O2 were used as oxidant gases. In the present work the decarburization of liquid Fe-C alloys was studied using an adaptation of the electromagnetic levitation technique, and thus the complexities introduced by crucible side reactions were eliminated. In this technique a single sphere of the Fe-C alloy is freely suspended and heated by electromagnetic induction in a flowing stream containing the oxidant gas. The full range of carbon levels up to saturation was studied, the temperature of the melts in this instance being held constant at 1660°C. The oxidant was CO2 which was used either pure or in association with a diluent gas, the total gas pressure being maintained either at 1 atm or at a reduced pressure. Thus the reaction under study was:

Jan 1, 1964

By P. A. Laxen, H. R. Spedden, A. M. Gaudin

WHEN a mineral particle is fractured, bonds between the atoms are broken. The unsatisfied forces that appear at the newly formed surface1 are considered to be responsible for the adsorption of ions at the mineral surface. A knowledge of the mechanism and extent of ion sorption from solution onto a mineral surface is of interest in the development of the theory of flotation.2,3 Study of the adsorption of sodium from an aqueous solution on quartz offers a simple approach to this complicated problem. The availability of a radioisotope as a tracer element meant that accurate data could be obtained.4,5 Three main factors which appeared likely to affect the adsorption of sodium are: 1-concentration of sodium in the solution, 2-concentration of other cations in the solution, and 3-anions present in the solution. Hydrogen and hydroxyl ions are always present in an aqueous solution. By controlling the pH, the concentration of these two ions was kept constant. The variation in the amount of sodium adsorbed with variation in sodium concentration was then determined under conditions standardized in regard to hydrogen ion. The effect of concentration of hydrogen ions and of other cations was also measured. A few experiments were made to get a preliminary idea on the effect of anions. The active isotope of sodium was available as sodium nitrate. Standard sodium nitrate solutions were used throughout these experiments except when the effects of other anions were studied. It was found that sodium adsorption increased with sodium-ion concentration, but less rapidly than in proportion to it. Increasing hydrogen-ion concentration, or conversely decreasing hydroxylion, brings about a comparatively slight decrease in sodium-ion adsorption. Increasing the concentration of cations other than hydrogen or sodium decreases somewhat the adsorption of sodium ion. It would appear as if the kind of anion is a secondary factor in guiding the amount of sodium ion that is adsorbed. Materials and Methods Quartz The quartz was prepared as in previous work in the Robert H. Richards Mineral Engineering Laboratory4 except for the refinement of using de-ionized distilled water for the final washing of the sized quartz, prior to drying5 To minimize the laborious preparation of quartz, experiments were made to determine whether the sodium-covered quartz could be washed free of sodium and re-used. The experiments were successful as indicated by lack of Na' activity on the repurified material and by its characteristic sodium adsorption. Table I gives the spectrographic analyses of the quartz used. The quartz ranged from 16 to 40 microns in size, averaging about 23 microns (microscope measurement), and had a surface of 1850 sq cm per g (lot I), 2210 (lot II) and 2000 (lot III) as determined by the Bloecher method.6 Radioactive Sodium Method of Beta Counting for Adsorbed Sodium: Na22, the radioisotope of sodium, possesses convenient properties.7 It has a half-life of 3 years, thus requiring no allowance for decay during an experiment. On decay it emits a 0.575 mev ß radiation and a 1.30 mev ? radiation. The decay scheme is illustrated in the following equation: [Y Nam S. - 'Net 3 years] The ß radiation is sufficiently strong to penetrate an end-window type of Geiger-Mueller counting tube. This, in turn, makes it possible to use external counting, a great advantage in technique. Furthermore, it permits the assaying of solids arranged in infinite thickness, while assaying evaporated liquors on standardized planchets. The equipment used was standard and similar to that employed by Chang8 The original active material was 1 ml of solution containing 1 millicurie of Na22 as nitrate. This active solution was diluted to 1000 ml. Five milliliters of this diluted active solution was found to give a quartz sample a sufficiently high activity for accurate evaluation of the sodium partition in the adsorption measurements. Also, 1 ml of final solution gave a sufficiently high count for precision on the liquor analyses. The sodium concentration of the diluted active solution was 1.2 mg per liter, so that 6 mg of sodium for 60 ml of test solution and 12 g of quartz was the minimum amount used. The active solution was stored in a Saftepak bottle. Procedure for Adsorption Tests: The method consisted of agitating 12 g of quartz with 60 ml of solution of known sodium concentration for enough time to establish equilibrium between the solution and the quartz surface. The quartz was separated as completely as possible from the solution by filtering and centrifuging. The activity on the quartz and in the equilibrium solution was measured and the partition of the sodium was calculated from the resulting data. The detailed procedure for the adsorption test is set forth in a thesis by Laxen5 In brief, it included the following steps: 1-Ascertainment of linearity between concentration of Na22 and activity measured. 2-Evaluation of factor to translate activity on solid of infinite thickness in terms of activity on an evaporated active film of minute thickness, on the various shelves of the counter shield. 3-Taking precautions to avoid evaporation of water during centrifuging.

Jan 1, 1952

By R. B. Woodworth

INTRODUCTION IN the sinking of bore holes, there are but two fundamental operations -drilling and hoisting,-which determine in the main the character of drilling mechanism and structures. There are endless ramifications, however, in the execution of these fundamental operations, according to the purposes for which the bore holes are drilled, their maintenance after completion, the protection and convenience of workmen, etc. The three main lines of use for bore holes are in mineral exploration, the sinking of water and salt wells, and the exploitation of petroleum and natural gas. This paper has to do more especially with the last. Here again there are many divergences. Wells may be drilled by either the percussive, the hydraulic, or the abrasive method. Finally, each of these methods, as applied by drillers of diverse nationalities, has followed somewhat different lines of development. The American system of cable-tool drilling has perhaps had the widest application; the hydraulic rotary is also in extensive use; but the Canadian system, the Galician system, and the Russian free-fall system all have their points of recognized merit and are preferred by operators accustomed to their use. These differences in drilling procedure, which rest ultimately on essential variations in geological conditions, are reflected in the chilling structures as well as in the drilling mechanism. The purpose of the present paper is to record those stages in the development of the application of steel to the construction of drilling mechanism and structures with which the writer has been intimately associated, and to contribute to the history of the art of drilling other data acquired in the course of his personal investigations. It is necessarily limited by reason of space to American practice, with especial reference, therefore, to the cable-tool system and the hydraulic rotary method of drilling wells for oil and gas.

Jan 11, 1915

By P. Beardmore, A. H. Holtzman, M. B. Bever

Specimens of the alloy CU3AU in the ordered and disordered states were subjected to explosive loading at shock pressures in the range from 160 to 475 kbars. The resulting changes in the resistivity, stored energy, microhardness, and microstructure were determined. By comparing the effects of explosive loading on ordered and disordered specimens a separation of structura1 and configurational changes has been made. In the pressure range from 290 to 370 kbars, representing a small increment of strain, the degree of long-range order in the ordered alloy decreased sharply. This change is attributed to the generation of shear stresses in excess of the theoretical shear strength of the alloy. Disordered CU3AU under explosive loading behaves in a manner considered to be characteristic of fee solid-solution alloys generally. The response of metals to high-velocity deformation and, in particular, to explosive loading has attracted much interest in recent years.' In general, metals are substantially strengthened by the passage of shock waves although the permanent strains are small. Explosive loading induces this strengthening by causing the metal to undergo rapidly a transient strain in a narrow region, first in the shock front and then in the rarefaction wave, which releases the pressure. The transient strain is given by e = 4/3 In V/Vo, where Vo and v are the specific volumes in the uncompressed and compressed states.2 The process produces many defects, which account for the strengthening. For the investigation reported here, an ordered alloy was chosen because it was expected to give sensitive indications of the near-neighbor effects produced by shock waves. The ordered alloy CU3AU was of special interest because of past work on the effects of conventional deformation on this alloy.314 The disordered alloy was included as a standard for comparison and as an alloy typical of a solid solution containing short-range order. The effects of explosive loading were followed by measurements of the resistivity, stored energy, and microhardness, and by metallographic examination. EXPERIMENTAL PROCEDURES Preparation of Specimens. Part of an ingot of the alloy Cu3Au prepared previously4 was cold-rolled with several intermediate anneals in vacuum to a final thickness of 0.042 in. Specimens of dimensions 2.0 by 1.0 by 0.042 in. were machined from this strip. After a recrystallization treatment of 1 hr at 565oC, half of the specimens were disordered by heating in evacuated Pyrex capsules for 1 hr at 460°C and quenching into water. Although they contained short-range order, they will be referred to as 'disordered" to indicate the absence of long-range order. The rest of the specimens were cooled slowly from 380°C to induce long-range order. The grain size of the ordered and disordered specimens was 0.012 mm. Explosive Loading. This was carried out at the Eastern Laboratory, Explosives Department, E. I. du Pont de Nemours & Co., by a driver-plate procedure described elsewhere.2 Two ordered specimens were stacked alongside two disordered speci-

Jan 1, 1964

By William G. [Peryam], Bishop Ottey M., Fred E. Johnson

THE Lepanto Consolidated Mining Company is the largest copper producer in the Philippines, and the only one that makes a concentrate valuable principally for its copper; also, it has the only productive copper mine situated at considerable distance from the sea, and is the only one in the islands operating its own smelter. The Lepanto mine is in the Municipal District of Mankayan, sub-province of Benguet, near the heart of the Mountain Province of Northern Luzon. It is 165 km. from its shipping point at San Fernando, Province of La Union, on the shore of the China Sea. Elevations at the property range from 3200 to 4500 ft. The climate is very mild; temperatures are seldom below 50° or above 80°F. Annual rainfall approaches 170 in. and is mainly confined to a rainy season lasting from May to October. The months from December to April, inclusive, are usually extremely dry. This climatic pecularity entails the problems of landslides on the roads during the rainy season and water shortage during the dry season. The Mountain Trail, an improved rock-surfaced toll road maintained by the Commonwealth Government, gives access to the property. The 105 km. over this road may be traveled in about 4 ½ hr. during the dry season. Very few sections of the road are straight for more than 100 meters, and about one third of it is a one-way road controlled by gates. All freight for the property is delivered by the Manila Railroad Company to Bauang, La Union, 45 km. west of Baguio and at sea level, where it is picked up by freight trucks and hauled via Baguio to Lepanto. Granulated matte is hauled in bulk from Lepanto in four-ton lots on freight trucks to the storage bins at San Fernando. Freight rates from Bauang to the property amount to P8.00 per ton, and from the property to San Fernando the rate is P16.00 per ton. The company pays the road toll, P1.00 per truck, each way. THE CAMP The company maintains a modern camp, well separated from the mine and reduction plant. Comfortable and sanitary living quarters, water, and light, as well as free medical service are provided all employees. A hospital staffed by a doctor and two nurses takes care of all medical treatment. Considering recreational facilities of great importance, the company has provided two tennis courts, two basketball courts, and badminton courts for employees. Bowling alleys and a motion picture theater are operated by the company, the profits being expended for other recreational purposes. A moderate sized recreation hall serves for barrio dances, meetings,

Jan 1, 1942

By Ralph A. Sherman, E. R. Kaiser

The remarkable increase in the distribution of the small underfeed stoker for use in furnaces and boilers in small industrial plants, apartment houses and homes has brought producers and distributors of bituminous coal to consider the problem of which coals and which sizes are best suited to this market. Many papers have also appeared, mostly in the trade journals, discussing the problem of the combustion of various coals and various sizes of coal in small stokers. Much difference of opinion has been apparent in these articles; due often, it would appear, to a misunderstanding of the fundamentals of the process of combustion in the stoker fuel bed. During the past year and a half, a program of research has been conducted at Battelle Memorial Institute: (1) On the process of combustion in the fuel bed of the small stoker, sponsored by Battelle Memorial Institute, and (2) on the relation of the characteristics of bituminous coals to their performance on small underfeed stokers, sponsored by Bituminous Coal Research, Inc. As a result of this program of research, two publications have been made, one1 dealing with the problem of clinker formation, and the other2 with the relation of the size of the coal fed to the stoker hopper to that of the coal that reaches the retort to be burned. The experimental research on the relation of size to the performance of the coal is being actively continued. A publication of Bituminous Coal Research, Inc. presenting the data obtained on the performance of several sizes of four typical bituminous coals will appear shortly. Because of the early appearance of that publication, the present paper includes few numerical data. The purpose of this paper is to follow the coal from the hopper through the furnace with a discussion of the various actions that occur, in the hope that it will lead to a clearer understanding of the relation of the type of coal, the size of coal, and other characteristics, to the performance. The authors do not pretend to have obtained the answers to all the complex questions involved; many unanswered questions will be proposed on which future research work is planned.

Jan 1, 1938

By Jos. Van Ackeren

Although the Siemens regenerator principle was introduced into byproduct coke-oven design about 40 years ago, many problems of construction, and particularly of heat distribution and pressure conditions, have not been fully solved. Heat should be applied to the walls of a coke oven in such a way that the coking of the charge of coal will be completed everywhere at the same time, and at approximately the same temperature. This means that the application of heat should be uniform from the top to the bottom of the coal mass (except for the thin layer at the top that is purposely kept at a somewhat lower temperature to reduce cracking of the byproducts); also that a little more heat must be applied to the coke end than to the pusher end, because the coal mass is a little thicker at that end. As a modern coke oven is about 40 ft. long and 12 ft. high, a real problem is involved in the proper application of heat to the oven walls so as to secure quick coking time (without endangering the walls through local overheating) and produce coke made at a uniform temperature. Design of Ovens In all regenerative ovens, the points of combustion are arranged in duplicate sets, one set operating in one-half the area of the heating wall and the other set alternately operating in the other half. Because of the reversal of the flow of gases, the points of maximum and minimum temperatures are alternately located at the same places, thus preventing dangerous local overheating. The practicability of the principle of reversal of flow seems to have been recognized at an early date, and has been applied with every conceivable flue arrangement, combustion chamber, and means of air and gas supply. To summarize the various principles that have proved useful for the control of oven-wall temperature, the best practice seems to have resulted from the acceptance of the use of vertical flues; the separate supply of air and gas to the base of these flues, with the resulting flame

Jan 1, 1923

By D. P. Morton

Since 1923, which closed the speculative era in the bituminous coal fields of the United States, there have been wide annual fluctuations in the national production of bituminous coal. These changes in annual output have been variously attributed to: (1) increased competition from petroleum products, natural gas and hydroelectric power; (2) lower unit consumption of coal; and (3) fluctuations in the general business level. The purpose of this paper is to measure, from a practical standpoint, the net effect upon the annual trend of bituminous coal production, and to give those who are interested a basis for estimating in advance the probable output of bituminous coal. It can readily be shown that changes in the level of general business affect the national production of bituminous coal more than does any other factor. Therefore it is necessary to use some standard measure of the relative business level for purposes of comparison. The Federal Reserve Board Index of Industrial Production offers the basis for such a measure.l This Index, a weighted composite of 81 different series, rests upon the averages of the years 1935 to 1939 as 100, and is presented graphically in Fig. I. Even a cursory examination of the chart will indicate a definite uptrend for industrial production over a period of years. This uptrend is due to at least two factors: (I) an actual increase in national population, and (2) a probable increase in the per capita consumption of goods. This means that there is no such thing as a fixed Normal, rather Normal is a variable, tending to increase from year to year. In order to measure the amount of annual increase in normal, the Index of Industrial Production must be studied in relation to its major components, Durable Goods and Nondurable Goods, Durable Goods are those made from the lasting materials such as iron, steel, other metals, lumber, stone, cement, clay, glass. Nondurable Goods are those for early consumption, such as foods, textiles, tobacco, chemicals, paper, gasoline, and goods made of leather and rubber. The purchase of Durable Goods may be postponed, but Nondurable Goods must be purchased currently unless the standard of living is lowered. The Federal Reserve Indexes of durable and nondurable goods are shown graphically, 1920 to 1939, on Fig. a (pp. 764-765 of ref. I). It is apparent that fluctuations in the production of nondurable goods are not nearly so wide as in the production of durable goods, and that the curve of Industrial Production (Fig. I) would fall between the two curves on Fig. 2. It would, however, seem logical that both curves should follow the same long-term trend, or that over a period of two to three decades the relative proportion of durable and nondurable goods, in periods of normal production, should be the same. It is neces-

Jan 1, 1942

By William A. Johnson

The mathematical analysis of diffusion curves in solid metals is carried out ordinarily by analogy with the flow of heat in a continuous medium and no account is taken of the fact that the materials involved are composed of discrete particles that move discrete distances at irregular intervals. It is possible to treat the problem on the basis of simple assumed atomic mechanisms, in which case, because of the small scale of the elementary process compared to the gross effects observed experimentally, the two procedures lead to the same expression for the variation of concentration with distance. Thus, for engineering purposes, the usual methods are quite satisfactory. If, on the other hand, our purpose is to go beyond the mere collection of data, however desirable this may be, it is necessary to recognize and understand the factors that are of fundamental importance. One factor that has not hitherto been considered when dealing with solid metals is the difference in atomic weights of the isotopes of a single metal. While all the atoms of a given element are alike chemically, their weights may vary by a small but significant amount, and atoms of different weights may have different diffusion rates. With gases this variation in isotopic weight produces a change in the rate of diffusion by a factor inversely proportional to the square root of mass. While, except for the lightest gases, this is not a large effect, it is, for example, sufficient to permit a considerable concentration of one isotope at the expense of others. If metals exhibit a similar phenomenon, some modification of the analysis of the diffusion process will be required, since the different isotopes of a given metal will have different probabilities of moving and the heat-flow analogy will contain a fundamental error. This situation cannot be rectified by using a diffusion coefficient based on the average probability of moving, and it can be shown that even when the diffusion coefficient is independent of composition, the diffusion curve will not agree with the simple theory except in the rare cases where only one isotope exists; e.g., gold. If, however, the mass effect in the solid state were no larger than in the gaseous, the errors arising therefrom in the analysis of ordinary diffusion curves would be quite negligible. Nevertheless, our desire to obtain all possible information concerning the details of the diffusion process, and the possibility of diffusion in the solid state as a means for separating isotopes are cogent reasons for undertaking an experimental study to determine whether isotopes of different masses diffuse at different rates. Experimental Procedure If isotopes of different masses diffuse at different rates, the ratio of the concentration of one relative to another will vary with the distance from the diffusion inter-

Jan 1, 1946

By William A. Johnson

The mathematical analysis of diffusion curves in solid metals is carried out ordinarily by analogy with the flow of heat in a continuous medium and no account is taken of the fact that the materials involved are composed of discrete particles that move discrete distances at irregular intervals. It is possible to treat the problem on the basis of simple assumed atomic mechanisms, in which case, because of the small scale of the elementary process compared to the gross effects observed experimentally, the two procedures lead to the same expression for the variation of concentration with distance. Thus, for engineering purposes, the usual methods are quite satisfactory. If, on the other hand, our purpose is to go beyond the mere collection of data, however desirable this may be, it is necessary to recognize and understand the factors that are of fundamental importance. One factor that has not hitherto been considered when dealing with solid metals is the difference in atomic weights of the isotopes of a single metal. While all the atoms of a given element are alike chemically, their weights may vary by a small but significant amount, and atoms of different weights may have different diffusion rates. With gases this variation in isotopic weight produces a change in the rate of diffusion by a factor inversely proportional to the square root of mass. While, except for the lightest gases, this is not a large effect, it is, for example, sufficient to permit a considerable concentration of one isotope at the expense of others. If metals exhibit a similar phenomenon, some modification of the analysis of the diffusion process will be required, since the different isotopes of a given metal will have different probabilities of moving and the heat-flow analogy will contain a fundamental error. This situation cannot be rectified by using a diffusion coefficient based on the average probability of moving, and it can be shown that even when the diffusion coefficient is independent of composition, the diffusion curve will not agree with the simple theory except in the rare cases where only one isotope exists; e.g., gold. If, however, the mass effect in the solid state were no larger than in the gaseous, the errors arising therefrom in the analysis of ordinary diffusion curves would be quite negligible. Nevertheless, our desire to obtain all possible information concerning the details of the diffusion process, and the possibility of diffusion in the solid state as a means for separating isotopes are cogent reasons for undertaking an experimental study to determine whether isotopes of different masses diffuse at different rates. Experimental Procedure If isotopes of different masses diffuse at different rates, the ratio of the concentration of one relative to another will vary with the distance from the diffusion inter-

Jan 1, 1946

By D. P. Morton

Since 1923, which closed the speculative era in the bituminous coal fields of the United States, there have been wide annual fluctuations in the national production of bituminous coal. These changes in annual output have been variously attributed to: (1) increased competition from petroleum products, natural gas and hydroelectric power; (2) lower unit consumption of coal; and (3) fluctuations in the general business level. The purpose of this paper is to measure, from a practical standpoint, the net effect upon the annual trend of bituminous coal production, and to give those who are interested a basis for estimating in advance the probable output of bituminous coal. It can readily be shown that changes in the level of general business affect the national production of bituminous coal more than does any other factor. Therefore it is necessary to use some standard measure of the relative business level for purposes of comparison. The Federal Reserve Board Index of Industrial Production offers the basis for such a measure.l This Index, a weighted composite of 81 different series, rests upon the averages of the years 1935 to 1939 as 100, and is presented graphically in Fig. I. Even a cursory examination of the chart will indicate a definite uptrend for industrial production over a period of years. This uptrend is due to at least two factors: (I) an actual increase in national population, and (2) a probable increase in the per capita consumption of goods. This means that there is no such thing as a fixed Normal, rather Normal is a variable, tending to increase from year to year. In order to measure the amount of annual increase in normal, the Index of Industrial Production must be studied in relation to its major components, Durable Goods and Nondurable Goods, Durable Goods are those made from the lasting materials such as iron, steel, other metals, lumber, stone, cement, clay, glass. Nondurable Goods are those for early consumption, such as foods, textiles, tobacco, chemicals, paper, gasoline, and goods made of leather and rubber. The purchase of Durable Goods may be postponed, but Nondurable Goods must be purchased currently unless the standard of living is lowered. The Federal Reserve Indexes of durable and nondurable goods are shown graphically, 1920 to 1939, on Fig. a (pp. 764-765 of ref. I). It is apparent that fluctuations in the production of nondurable goods are not nearly so wide as in the production of durable goods, and that the curve of Industrial Production (Fig. I) would fall between the two curves on Fig. 2. It would, however, seem logical that both curves should follow the same long-term trend, or that over a period of two to three decades the relative proportion of durable and nondurable goods, in periods of normal production, should be the same. It is neces-

Jan 1, 1942

By G. H. Edmunds, C. H. Mathewson

About fifty pages of Henry M. Howe's profound treatise, "The Metallography of Steel and Cast Iron," are devoted to twinning with special reference to the origin, nature and general significance of the Neumann bands in ferrite. Howe believed with Osmond and Cartaud1 that the Neumanns are mechanical twins and his careful observations leave no doubt that these straight-sided narrow bands habitually occur parallel to trapezohedral planes of form {211). Attempts to develop the structure of the bands by various methods SO that their identity could be established beyond question have not been conspicuously successful. Howe thought that they deflected slip bands. Some of the etching figures which have been developed within and adjacent to Neumann bands support the contention that they are twins. A good example of this effect in ferrite containing 0.6 per cent, of niekel and 1.3 per cent. of phosphorus, originally due to Harnecker and Rassow,2 was reproduced in the 1928 lecture before the Institute of Metals Division on twinning in metals.3 In this case, the sides of the figures might represent the traces of cubic planes laid bare by etching a properly oriented grain of ferrite, twinned along a plane of form (211). Our own observations in this direction may be represented by Fig. 1 which shows in a deeply etched cavity in the boundary region between a Neumann band and the original crystal two small crystal surfaces which resemble the faces meeting at a reentrant angle in the simple cube twinned along a bisecting plane of form (211) as sketched in Fig. 2. Rosenhain and McMinn4 in 1925, after a careful study of slip bands in ferrite containing Neumanns previously produced by shock, concluded

By Jos. Van Ackeren

Although the Siemens regenerator principle was introduced into byproduct coke-oven design about 40 years ago, many problems of construction, and particularly of heat distribution and pressure conditions, have not been fully solved. Heat should be applied to the walls of a coke oven in such a way that the coking of the charge of coal will be completed everywhere at the same time, and at approximately the same temperature. This means that the application of heat should be uniform from the top to the bottom of the coal mass (except for the thin layer at the top that is purposely kept at a somewhat lower temperature to reduce cracking of the byproducts); also that a little more heat must be applied to the coke end than to the pusher end, because the coal mass is a little thicker at that end. As a modern coke oven is about 40 ft. long and 12 ft. high, a real problem is involved in the proper application of heat to the oven walls so as to secure quick coking time (without endangering the walls through local overheating) and produce coke made at a uniform temperature. Design of Ovens In all regenerative ovens, the points of combustion are arranged in duplicate sets, one set operating in one-half the area of the heating wall and the other set alternately operating in the other half. Because of the reversal of the flow of gases, the points of maximum and minimum temperatures are alternately located at the same places, thus preventing dangerous local overheating. The practicability of the principle of reversal of flow seems to have been recognized at an early date, and has been applied with every conceivable flue arrangement, combustion chamber, and means of air and gas supply. To summarize the various principles that have proved useful for the control of oven-wall temperature, the best practice seems to have resulted from the acceptance of the use of vertical flues; the separate supply of air and gas to the base of these flues, with the resulting flame

Jan 1, 1923

By W. A. Ver Wiebe

It is becoming increasingly apparent that the State of Kansas contains one of the largest reserve areas for oil exploration in the United States. During the year 1936 no less than 54 new oil pools were discovered by drilling. In addition, seven gas pools were found, which may develop into oil pools when deeper horizons are tested. Several old pools increased their reserves when production was found in lower strata. The data presented in Table 2 indicate that nearly 2000 wells were drilled in the state during 1936. Of these more than 1214 found commercial quantities of oil and at least 61 found marketable quantities of gas. The data are conservative because complete results on drilling are not available for the eastern part of the state. Ellis, Rice and Russell Counties share honors with a total of 10 new pools in each. Barton County is prominent with six pools; while those counties claiming fewer new pools are Clark, Ellsworth, Harvey, McPherson, Ness, Pawnee, Rooks, Stafford and Trego. Important additions to our gas reserves were found in Finney and Haskell Counties, which are north of the extensive Hugoton gas area and may some day be part of it. At the close of the year there were 17,317 wells in the state rating as producers. By far the larger share (14,000) were classed as strippers and allowed to flow 100 per cent of their potential capacity, thus accounting for 33,500 bbl. a day. The remaining wells, capable of producing from 15 up to over 6000 bbl. per day, were limited in output according to these amounts. The largest wells having a potential of from 3000 to 7000 were allowed to flow from 2 to 3½ per cent of their official potential capacity. The percentage rises until wells of 15 to 20-bbl. capacity have a rating of slightly over 83. On the basis of these calculations the total potential capacity of all wells was 1,667,814 bbl., and the daily amount allowed was 175,851. Nine of the pools most recently opened were still unable to market their oil and were classified as "shut-in" pools. Total production for the state for 1936 was somewhat over 58 million barrels. Striking Geological Data Some interesting geological data were uncovered by deep drilling during the year. The most remarkable bit of information is the discovery

Jan 1, 1937

By J. H. Hollomon, J. C. Fisher

THE fundamental problem concerning the fracture of both crystalline and noncrystalline solids is the divergence between the actual and the theoretically computed fracture stresses; the stress required for fracture, computed from the forces between atoms, is many times that actually observed with commercially available materials. Computations have been made1, 2 indicating that the theoretical fracture stress should be from 100 to 1000 times that actually observed. There are other incidental problems that have arisen, perhaps the most important of which is the problem of size effect often observed in the measurement of the fracture stress of non-metallic solids, such as glass. Another effect concerns the relation between deformation and the stress required for fracture. Experiments recently made with pearlitic steels indicate that the tensile fracture stress increases with increasing tensile deformation and decreases with increasing prior compressive deformation. This marked anisotropy of the effect of deformation on the fracture stress is in contrast with the essential isotropy of the flow stress. Early experiments on rock salt crystals by Joffé, et a13 have illustrated the effect of tensile strain in increasing the tensile stress required for fracture. A consistent theory must be constructed that will explain not only the divergence of the measured fracture stress from the theoretical value, the size effect, and the effect of deformation; but will also explain and predict the effects of combined stress, of temperature, of strain rate, and of metallurgical structure. With respect to this last variable, it has now been relatively well established that the carbide particle is the element of structure controlling the fracture of steels. In steels carbide particles vary in shape from plates to spheroids. It has been found that not only does the magnitude of the fracture stress depend upon the size and shape of these particles, but also its dependence upon strain is affected by changes in shape and size of the particles. The precipitate resulting from the age hardening of duralumin also modifies the fracture stress of this alloy. Nonmetallic inclusions greatly lower the fracture stress of all metals. The magnitude of the lowering depends on the size and shape of the included particles. In glass, the major source of the low fracture stress has been fairly conclusively demonstrated by Griffith4 to arise from real flaws or cracks present in the material. He showed that the stress concentration at the end of a defect was of sufficient magnitude to raise the stress at this location to a value comparable with the theoretical strength of the material. If the cracks were reduced in size, Griffith showed that the observed fracture strength increased by virtue of the decrease in stress concentration. He also pointed out that cracks disposed perpendicularly to the applied tensile stress would be more effective in lowering the fracture

Jan 1, 1947

By John Goheen

RECENTLY the head burner at a brick. plant with over 40 years' experience said that he had burned brick by guess for over half his lifetime and had used pyrometers for 2 1/2 years but hoped that he would never have to burn kilns without pyrometers again. The ceramic engineer in making a special study of the burning of clay ware and the effect the heat of the kiln has on color and vitrification is also rapidly placing the burning of clay on a twentieth-century basis. Clay ware may be divided into various groups, brick and drain tile; sewer pipe; firebrick; and pottery, which, in turn may be subdivided into special classes. As nearly as the analysis of the clay type of kiln, etc., will allow, there are practically the same problems to solve in burning in all of the processes or operations. The underlying objective is the same, namely the production of the best grade of ware under the most efficient and economical manufacturing system. The principal problem in the production of clay ware is the burning off of the kilns. The most modern steam shovel may dig the clay and the most advanced types of pug mills and wire cut machines or molds of various kinds may be installed, but unless the drying and burning of the ware is successful, all of the previous operations will be useless. On this final operation depends the entire result of the plant. In reality, burning of all. clay ware is purely a heating proposition. The kilns, or furnaces, should be so designed as to give equal distribution of heat. Consequently, the problems of design and construction of kilns to produce equal distribution of heat require serious consideration, as do also the questions of heat control and draft control. The three most important factors in the burning of practically all types of kilns may be

Jan 9, 1919