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By V. Damiano, M. Herman

CELLULAR substructure observed in metal crystals grown from the melt. has been studied extensively'-' and is attributed to the existence of a constitutionally supercooled zone in the liquid ahead of the solidifying interface. The mathematical description of this process has been given in terms of the concentration of solute in the liquid phase, the rate of solidification, and the temperature gradien.t in the liquid as the only variables.5 This technical note presents some evidence of 1) the effect of crystal orientation on some aspects of cellular growth, and 2:) the degeneracy of these cells into dislocation arrays. The zinc single crystals used in these studies were alloyed with cadmium sufficient to produce the constitutional supercooled cellular substructure. Crystals containing 0.05 pct Cd exhibited substructure formation for a growth rate of 10 cm per hr and a temperature gradient of 15°C per cm in accord with the theory. The growing liquid-solid interface was examined after we liquid had been decanted away in a fashion similar to that described by Rutter and Chamers.' The cellular substructure was also observed after polishing and etching the surface directly behind the decanted interface with a solution of HNO, and water. Fig. 1 is a photomicrograph of a typical polished and etched surface revealing substructure, the cleavage plane, and twins. The crystal has been grown with its basal plane parallel to the direction of growth and the plane of the micrograph is per-

Jan 1, 1960

By S. Fugleberg

As a result of research work done during the planning of the Kokkola zinc plant it was found that a very efficient cementation of impurities from the suspension obtained after leaching copper and cadmium cakes was achieved by adding zinc dust to the batch without filtration after the leaching. All elements nobler than cadmium are precipitated with the exception of lead, which must be removed in a separate step. Using pure zinc dust, free from noble metals, the cadmium sponge produced will only contain elements that can be re- moved from cadmium by meltrefining. The process is thus : 1. Leaching and purification 2. Removal of lead (with BaCO3) 3. Precipitation of cadmium sponge with pure zinc dust 4. Meltrefining of briquetted sponge with NaOH for removal of Zn (and others) The paper deals with the removal of the most critical elements, i.e. Co, Ni, As, Sb, Cu, Pb, T1 in the liquid phase and Zn and T1 in the melt. A survey is also given of the behaviour of most of the other elements normally found in Cd raw material, such as Ge, Te, Se, Sn, In, Ga. It is shown that in most cases the benefit of an electrolysis in Cd production is very limited. In Kokkola 99.998% Cd is achieved by this method, but in favourable cases it may be possible to come quite close to five nines.

Jan 1, 1973

By Rodolfo V. de la Cruz, Richard E. Goodman

Knowledge of the initial state of stress in rocks provides a key to the solution of many problems in rock mechanics. The initial state of stress is part of the basic data required for rational design of structures in rock, since its redistribution when engineering activities are conducted is a primary load on the rock portion of the engineering system. Knowledge of initial and subsequent changes in the state of stress is also relevant in the study of active faults and crustal strain. The purposes of stress measurements are not generally well served by methods which disclose only one of the stress components at a point. Recently, interest has centered on overcoring methods which though ex- pensive and difficult have the important advantage of yielding data on three or more stress components. In a previous paper, the authors introduced a new method-termed borehole deepening-based on measurement of the deformations that occur close to the bottom of a borehole when it is deepened by further drilling without overcoring.l The proposed method is at a disadvantage when compared with over- coring procedures in that the quantities to be measured are somewhat smaller and the measuring environment is more hostile. However, the borehole deepening method presents three distinct advantages in comparison with overcoring procedures: (1) Using the same borehole, both the initial and the subsequent changes in the state of stress can be obtained by borehole deepening. Stress changes with time are

Jan 1, 1970

By D. K. Crampton

NEARLY everyone who has not had the benefit of study in the field of metallurgy subscribes to a persistent and enthusiastic belief in the legendary lost art of hardening copper. This of course supplies a perfect introduction to a chapter of information on copper and its alloys, since the dissipation of fallacies and superstitions affecting an art probably constitutes the best method of getting at its real substance. Metals are hardened, but also embrittled, by a plurality of impurities. In the modern technology of copper-base metal products, we are familiar with a great host of materials, passing from one extreme of dead soft copper better than 99.9 pct pure, which in the form of wire about as thick as a match will stand hundreds of full twists in a 12-in. length, to an alloy containing less than 3 pct of alloyed substance possessing the strength of pretty good steel and capable of manufacture into razor blades, should we suddenly be deprived of steel; certainly a much better material for this purpose. Every copper alloy known to primitive man lies in some inter- mediate position and the ancient bronzes that have been found all over the world wherever an early civilization existed are usually contaminated by such impurities as sulfur, oxygen, antimony, arsenic, iron, or other materials, so that they could not possibly conform to any modern intelligent specification insuring the best combination of useful properties in alloys of their type and would go

Jan 1, 1953

By E. G. Leonardon

THE first to appreciate and foresee the value of applying electrical measurements to structural studies was Prof. Conrad Schlumberger, Professor of Physics at the School of Mines in Paris. One of his earliest practical undertakings in this line was carried out, in the field, at Fierville-la-Campagne, Normandy, in 1912. His book, published in 1920,1 still stands as an authoritative, fundamental treatise on the use of the electric current in geological studies, in spite of the rapid evolution of geophysics during the last seven years. A remarkable feature of this book is that, even then, it stressed the role of electricity in structural investigations and made public the first successful results obtained therewith. Stratigraphic studies have been pursued continuously by Conrad Schlumberger and his associates since 1912, the only interruption being the World War. The results attained demonstrate the wide possibilities of electrical exploration in structural work. This field of activity is, at the least, as varied and valuable as the search for ore. It is curious that until very recently it has so slightly attracted the attention of geophysicists and geologists on this continent. The purpose of this paper is to present briefly some examples of the practical application of the potential methods to geological studies. These examples are chosen from a number of problems solved in the field by our firm, in the course of its consulting practice. Certain fundamental points are briefly stated before the field operations and interpretations are described.

Jan 1, 1928

By Robert H. Hafner, Irvin R. Kramer

IN recent years considerable interest has been shown in surface-alloyed metals, particularly those of chromium (chromized steels), which have excellent corrosion [ ] resistance under a variety of severe conditions, and may undergo bending and flanging operations without spalling. An early method' employed to produce a high-chromium case on steel was developed by Kelley in 1921. It consisted of heating a low-carbon steel in intimate contact with powdered chromium in the presence of hydrogen at temperatures sufficiently high to permit diffusion of chromium into the steel. The usefulness of this process was limited because the extremely high temperatures of 1200° to 1400°C. (2200° to 2550 F.) caused excessive grain growth and warpage. Louenstein and Ulmer2 packed iron castings in ferrochromium and com- [ ] mon salt, and heated for approximately three hours at 930° to 1040°C. (1700° to 1900°F.). A recent and more practical method of depositing chromium on steel surfaces has been developed in Germany by Daeves, Becker and Steinberg3-8 and in Russia by Izgaryshev and Sarkisov.9 This process consists of passing gaseous chromium chloride over the steel to be chromized at temperatures of 900° to 1000°C., or packing them in a porous, ceramic material that previously had been saturated with chromium chloride. They reported obtaining a chromized layer, 0.004 in. thick, on low-carbon steels. Later, Daeves4 established a relationship between the carbon content

Jan 1, 1942

By R. W. H. Acherson

Blast-furnace flue dust is one of the most troublesome operating factors in the iron and steel industry. It is usually involved in all the unpleasant phases of blast-furnace operations. It adds to our aggravations until we are willing to spend large sums of money to keep it out of our stoves and boilers and more money to handle it again and again on one scheme or another to induce the furnaces to retain it without bad after effects. Several successful operators claim that it is useless to recharge raw flue dust because the furnace would never have blown it out if it had been suitable material for blast-furnace consumption. Most of us who have made persistent efforts to return raw flue dust to the furnaces have decided that it is very often false economy to do so. Yet some remarkable results have been attained at the Ohio Works of the Carnegie Steel Co. through recharging raw dust. The plant comprises six modern blast furnaces. Up to 1909, about 300,000 tons of flue dust had accumulated in stock piles. During the last 10 years, there have been recharged into these furnaces all of the flue dust recovered from the furnace operations, the entire stock pile of Rue dust, and nearly 80,000 tons of dust shipped from other furnaces of the Carnegie Steel Co. The results obtained arc. shown in Table 1.

Jan 1, 1922

By M. Muskat R. D. Wyckoff

The phenomenon called "water-coning" is that, observed in many oil wells, in which bottom water gradually and frequently sudderlly displaces a part or all of the oil production when a certain rather critical production rate from the well is exceeded. To follow in detail the process of the formation of a water cone as it breaks through the oil zone and enters the well bore is a problem so complex as to make a theoretical analysis practically impossible. However, an analytical treatment of the flow system before the water has broken through and during the time that it lies statically beneath the oil zone with an elevated or "coned" surface can be carried through under certain approximations. To present an analysis which shows the essential characteristics of the coning mechanism is the purpose of the present discussion. Physical Basis of Theory and Meaning of Approximations As will always be true for flow systems where true water-coning is at all possible, the water will be supposed to lie beneath the oil zone because of its density contrast with respect to the oil. In fact, tinder the usual field conditions, when the pay horizon is reasonably homogeneous, the water most frequently enters the well through the lower zones, but even when it enters from intermediate zones it may, in the later life of the well, displace the bottom layers of oil, thus resulting in a system wherein the oil is effectively floating on the water.

Jan 1, 1935

By H. Foster Bain

[Secretary's NoTE.—This paper, presented in oral abstract at the San Francisco meeting, was not at first supposed by Mr. Rain to be required for publication in the Transactions; and the excursion to Japan, in which he took part, immediately after the San Francisco meeting, delayed his presentation of the manuscript. After his return to San Francisco, Mr. Bain, in view of the importance of his paper and its discussion, kindly furnished it in full. The delay in its publication (since it was received in April last) has been due, partly to the circumstance that other contributions had meanwhile acquired the " right of way," and partly to the consideration that, the situation contemplated in Mr. Bain's paper having remained practically unchanged, the paper and its discussion would not lose force or timeliness by this lapse of time.—J. S. ] No acute observer of public affairs can have failed to observe a growing disposition on the part of the public to change emphasis in government from political equality to social justice. When our own government was founded it was felt to be sufficient to secure to each individual the fullest possible freedom of opportunity, and such a scheme was excellently adapted to the rapid development of a large territory having a small population. As the number of people in a given area increases, there are more points of contact and conflict; each must move in a smaller orbit, and there must be more regula-

Jan 1, 1913

By W. H. Emmons

A DIATREME is a hole blown through a rock by gases, presumably of volcanic origin. Not all pipes of ore have formed by deposition of metals in such openings, but a con-siderable number have so formed. In this paper are described peculiar vein patterns that are believed to be incipient diatremes or "perforation pipes." Grading into this group is one showing thorough brecciation without rotation of fragments and into the latter a group of ore pipes showing brecciation with rotation of fragments-many of them with well rounded fragments. Also, volcanic craters or volcanic necks are explosion pipes. These may carry ore deposits along their contacts and some carry deposits within the pipes. As new data appear this group becomes increasingly impressive. It has been shown that veins are concentrated in and about cupolas of batholiths and that such veins commonly lienearly parallel to the long axes of cupolas as these are shown on plans. It would be supposed that conical cupolas would have radial patterns, but few vein systems exhibit radial patterns. It is probable that explo-sion pipes also may form in areas above conical cupolas. From these the gases escape more violently because the loads above them are less than above an elongated cupola where larger bodies of rock are affected. The hypothesis is sound mechanically, for the top of an elongated cupola is a line whereas the top of a conical cupola is a point.

Jan 1, 1938

By Richard E. Gray, William S. McCann, Robert C. Speck, Robert W. Bruhyn

Subsidence of the ground surface is the inevitable result of high recovery longwall and room and pillar coal mining operations. Up to now, U.S. research into this phenomenon has been concerned primarily with documenting the magnitude and extent of ground movements and prediction of the attendant ground strains through traditional ap¬proaches that have been developed in Europe and the United Kingdom. Preoccupation with ground strain prediction has, unfortunately, diverted attention from the more meaningful objective of predicting the severity of damage to structures at ground surface and the prob¬able cost to repair such damage. An attempt has been made to rectify this situation by reviewing in detail one hundred thirty four cases of subsidence damage to dwellings above active mines in western Pennsylvania, identifying the types of damage and the circumstances under which damage took place. The data reveal that damage to dwellings virtually always includes basements in addition to the readily apparent effects to the superstructure. In 90 percent of the subsidence cases, more than half the repair cost is associated with damage to subgrade components. A damage classi¬fication system has been devised that relates observed damage to severity and repair cost in a uniform manner for conditions in the Northern Appalachian Coal Field. Damage severity has been examined in the context of depth to the mine, the character of the near¬ surface overburden materials, mining type and other parameters.

Jan 1, 1983

By R. W. Diamond

THREE mills are now operated by the Consolidated Mining & Smelting Co. of Canada, Ltd.: (1) The Sullivan Concentrator, Chapman Camp, B. C. (near Kimberley, B. C.), (2) the, St. Eugene Concentrator, Moyie, B. C., and (3) the. Tadanac (Customs) Concentrator,Trail, B. C. Differential flotation is the only concentration method employed in all three plants. Tables are used for pilot work only. Values in all ores treated are as minerals of some or all of the metals -lead, zinc, gold or silver. Occasional customs ores contain small amounts of copper. Sulfide iron content of ores treated varies from a FIG. 1.-THE SULLIVAN CONCENTRATOR, CHAPMAN CAMP, B. C. (NEAR KIMBERLEY, B. C.). low figure in some ores to 38 per cent. iron in Sullivan ore. Gangue minerals vary considerably. A few customs ores are somewhat oxidized and as a result present difficulties. Flotation equipment and control are similar in the three mills, and the flow sheets at the St. Eugene and Tadanac mills, while much simpler, are modeled after that of the Sullivan Concentrator. In this paper I will not detail treatment nor equipment in any of our plants but will describe special features in, or in connection with, all of them. I will then deal with flotation reagents, describing our use of each of them, particularly where differing from general practice. I will conclude with comments on special subjects related to differential-flotation.

Jan 1, 1927

By Phillip O. Tyree, Joseph W. Mussey

Bio-epigenetic sulphur deposits occur in Pecos, Reeves and Culberson Counties of far West Texas. Sulfate reducing bacteria, utilizing hydrocarbons as energy, transformed gypsum into replacement limestone and hydrogen sulfide. Hydrogen sulfide, retained in the pores of the replacement limestone, was subsequently oxidized by highly oxygenated groundwaters, and native sulphur precipitated. West Texas sulphur was first recognized at surface exposures by William P. Blake, a geologist attached to the Captain Pope Military/ Scientific Expedition of 1854. Attempts were made in the early 1900's to mine these sulphur vent exposures by a retort method, but the ventures met with little success. In 1967, Duval discovered a large sulphur deposit near some of the old sulphur works in Culberson County. Duval also expanded reserves in a small sulphur deposit in Pecos County. The Frasch process, developed for producing sulphur from Gulf Coast salt domes, proved successful in West Texas type sulphur deposits also. However, modifications of the process were necessary to provide economical and efficient sulphur recovery from the varied ore occurrences. West Texas conditions and logistics require the ultimate in productivity to be competitive in the domestic and foreign sulphur markets. Several companies, in addition to Duval, are producing or have produced sulphur in West Texas. As of June 1, 1984, a total of 29.87 million mt (29.4 million long tons) of sulphur had been produced west of the Pecos River. Duval Corporation has produced more than 88 percent of that total.

Jan 1, 1985

By R. W. H. Acherson

Blast-furnace flue dust is one of the most troublesome operating factors in the iron and steel industry. It is usually involved in all the unpleasant phases of blast-furnace operations. It adds to our aggravations until we are willing to spend large sums of money to keep it out of our stoves and boilers and more money to handle it again and again on one scheme or another to induce the furnaces to retain it without bad after effects. Several successful operators claim that it is useless to recharge raw flue dust because the furnace would never have blown it out if it had been suitable material for blast-furnace consumption. Most of us who have made persistent efforts to return raw flue dust to the furnaces have decided that it is very often false economy to do so. Yet some remarkable results have been attained at the Ohio Works of the Carnegie Steel Co. through recharging raw dust. The plant comprises six modern blast furnaces. Up to 1909, about 300,000 tons of flue dust had accumulated in stock piles. During the last 10 years, there have been recharged into these furnaces all of the flue dust recovered from the furnace operations, the entire stock pile of Rue dust, and nearly 80,000 tons of dust shipped from other furnaces of the Carnegie Steel Co. The results obtained arc. shown in Table 1.

Jan 1, 1922

By R. F. Shurtz

The author proposes a method used with some success on a magnesite deposit at Gabbs, Nev. He believes this procedure to be more sound than the blind practice of assigning uniform quality to large, soinetimes vast blocks or ore on the basis of analyses made of a small number of samples. When an ore deposit is evaluated on the basis of core sampling, questions always arise as to how much weight should be given the various sample grades and how the deposit should be divided into specific volumes assigned to corresponding grades. For a tabular deposit it is customary to use the so-called zone-of-influence. This zone is usually defined as the polygon in the plane of the deposit having corners halfway between a given core drill intersection and each of the nearest neighboring intersections. The volume of the ore in this polygon is assigned the analysis obtained from the drill core taken at the intersection. In massive or irregular deposits, volumes of various shapes may be defined with respect to the locations of drill core samples. These volumes may be regarded as three-dimensional zones-of-influence; the theory involved in assigning the values of the central analyses to the ore in the volumes is the same as that used in the case of a tabular deposit. The zone-of-influence method was used in evaluating one of the magnesite deposits at Gabbs, Nev.'-"

Jan 1, 1960

By P. Ramachandrarao, T. R. Anantharaman

CONSIDERABLE interest has lately been evinced as regards the nature of chill zones in solidified metals and alloys. Biloni and Chalmersl were the first to show through their study of segregation substructures in some nonferrous alloys that the formation of the dendritic region may be preceded by a diffusionless solidification process, viz., predendritic solidification. Subsequently Bower and Flemings2 tried a special solidification technique wherein the liquid was drawn into a narrow copper mold with polished surfaces and concluded that convection might trigger some multiplication mechanism leading to grain refinement. Using uncoated and partially coated surfaces for molds in the Bower-Flemings technique as well as in conventional molds, Biloni and Morando3 have very recently brought out the importance of the rate of heat extraction on the mechanism of solidification. We report here on the surface structures and substructures observed in a Sn-1 wt pct Pb alloy solidified at even higher cooling rates (riz., l05 to l07 ºc per sec) than those employed by earlier workers. The alloy was made by melting tin (99.99+ pct) and lead (99.9+ pct) in a silica tube under vacuum. Small quantities of the homogenized alloy (0.5 to 1.0 g) were then quenched (or splat-cooled) from the melt by the "gun technique" developed by Duwez et al.4 The thickness of the resultant foils varied from specimen to

Jan 1, 1970

By Robert Roberts

(Butte Meeting, August, 1913.) IN order to obtain data on the thermal effect of the blast-furnace jacket and oil the water consumption in these jackets a series of tests were run on the 56 by 180 in. blast furnaces at the Great Falls Reduction Department of the Anaconda Copper Mining Co., at Great Falls, Mont. The arrangement of the jacket is shown in the transverse section of one of the furnaces (Fig. 1) on which the tests were made. The nose, spout, and breast jackets have independent water supplies and discharges. The end and side jackets are connected in pairs, as regards water supply, the feed water entering at the bottom of the lower jacket and overflowing into the bottom of the jacket immediately above it, and discharging into an independent overflow pipe for each pair of jackets. Tests were run on the main side and end jackets, the breast jacket, the spout, and the nose. Measurements were taken of the quantity of water discharged per minute and the rise in temperature of the water in its passage through the jacket. The product of these two results, expressed in the proper units, evidently gives the number of units of heat removed per minute by the water. Sufficient work was done on each type of jacket to determine its behavior under different conditions, and the results from each set of conditions were checked by repeating the work from three to six times.

Jan 7, 1913

By J. A. Jr. Church

I. EARLY FURNACES. . COPPER blast-furnace construction in America has long recognized a general standard in the rectangular water-jacketed shaft with separate forehearth. The details, however, and especially those relating to shaft dimensions, have had to meet a great variety of conditions, and show no uniformity whatever. Selecting a few of the present day Western plants, we find furnace lengths varying from 12.5 to 87 ft., widths at tuyere level from 42 to 84 in., and heights above tuyeres from 5 ft. 4 in. to 22 ft. 4 in. ; and comparing present designs with those of the past, we meet contrasts no less striking. Unlike its transverse section, the length of a furnace has come to depend rather on the size of unit desired than on the requirements of smelting ; and if the question of length be ignored, several of the various existing designs can be grouped together on the basis of a common transverse section. This section, having a width at tuyere level of 56 in. and a height above tuyeres of 18, ft., was developed at Great Falls, and the story of its development contains some interesting features. Ground was broken for the Great Falls works in the spring of 1891. About a year later, the concentrator was able to begin operation, followed within the next few months by the Brueckner, reverberatory, and converter departments, and in April, 1893, by the first blast fur-

Jan 7, 1913

PRESENTATION of the 1922 Washington Award to Capt. Robert W. Hunt, honorary member and twice president of the Institute, was made at the annual dinner of the Western Society of Engineers, in Chicago, on June 18, 1923, in the presence of 250 mem-bers and guests. W. L. Abbott, Chairman of the Award Commission, when delivering the presentation address, said The life of the Govern-ment of this country, as the lives of governments are usually measured, is short, barely 150 years, but meas-ured by what it has accom-plished, this country has reached a venerable age. The first 75 years of our country's existence were necessarily preparatory to the greater developments which came in the second, and that last half of our country's existence is ex-ceeded, by ten years, by the span of life of our honored guest. "Very little iron and steel were produced in this coun-try until after the birth of Robert W. Hunt. And it was not until after 1860, when as a boy of 21 he joined his fortunes with those of the Cambria Iron Works, that the iron and steel business of the country really took root. After a year or two with the Cambria Works, he left a promising position to go into the army, where he served for four years. After the close of the war he returned to the iron works and qualified himself as a metallurgical chemist.

Jan 7, 1923

By D. D. Dunkin

SANDSTONE has been prepared for glassmaking purposes, and marketed from the White River Valley in-Arkansas at Guion, Izard County, since about 1910-soon after the completion of the White River Branch of the Missouri Pacific R. R. Co. Until 1921, operations were somewhat spasmodic and ended in many failures. In that year a plant was built by the Silica Products Co., Inc., and since that time the operation has been continuous and steady. The land is held under leases, covering about 30 sq. mi. of the best sandstone adjacent to the railroad. Most of the product is shipped to glassmakers. GEOLOGY The St. Peter sandstone is rather widely distributed in north central Arkansas and- is exposed most prominently in outcrops along the slopes of the White River Valley and its tributaries that form the division between the Boston Mountains to the south and the Salem Plateau of the Ozarks to the north. It is of Ordovician age and is generally underlain by Cotter dolomite and capped by Plattin limestone, except in the vicinity of Bellefonte and Everton. At those places, it is a massive cross-bedded, laminated, saccharoidal sandstone; underlying it is the Everton limestone and overlying it, the Joachim magnesium limestone. The sandstone at Everton contains numerous phosphatic pebbles and inclusions of sandy limestone. The irregularity of cross-section, the evidence of sorting action and the phosphatic pebbles appear to be indications of secondary deposition.

Jan 1, 1928