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By J. F. Breedis

The stabilization of austenite in Fe-Ni alloys against martensitic transformation after reversion has been attributed' to the lattice imperfections remaining from previous transformation. More recently, however, such stabilization has been associatedzy3 with compositional changes which occur in martensite during slow heating. Dislocation arrangements in deformed austenitic stainless steels strongly influence transformation to martensite on quenching.4 Therefore, it is of interest to observe the transformation behavior of stainless steel after reversion, especially since previous studies have been confined to Fe-Ni alloys. The transformation-product morphology also differs in the two iron-alloy systems;6 plate martensite forms in the latter while stainless steel transforms to lath-type martensite. Samples of Fe-16 wt pct Cr-12 wt pct Ni (maximum C + N = 0.005 wt pct, 0 = 0.02 wt pct), prepared by vacuum melting and casting from high-purity components, were annealed at 900°C for 24 hr, after cold rolling to produce a 40-p grain diameter. The M, temperature of this alloy is -80°C and samples are fully austenitic after annealing. The amount of martensite present after quenching, annealing, and requenching was determined magnetically, to within 0.01 wt pct, using a vibrating specimen magnetometer. Nearly 14 pct of martensite forms during the initial quench in 1 min at -196°C. Two-min and 2-hr anneals were done in air and in evacuated quartz capsules, respectively. All specimens were electro-polished before making the magnetic measurements.

Jan 1, 1967

By H. B. Kinnear

THE first copper stool used under an ingot mold to receive molten steel has recently been taken out of service after it had received ingots amounting to 6012 gross tons. This stool, weighing 8330 lb. had been in continuous service for 1822 heats since its installation. From this modest beginning the use of copper for ingot-mold stools grew to 425,000 lb. in 1934, with an additional 50,000 lb. of copper used in the form of inserts in cast-iron stools. During 1935 the quantity of copper used for stools increased by about 350,000 lb., making a total of 775,000 lb. now in use for that purpose. Copper used for inserts has increased during this time 180,000 lb., or over 350 per cent, to a total of 230,000 lb. The total of copper, therefore, in use at present under ingot molds is slightly over 1.000,000 lb.

Jan 1, 1936

By R. E. H. Pomeroy

THE statistical data given in this paper are taken from the actual performance of the No. 2 reverberatory furnace of the Nevada Consolidated Copper Co., Me Gill, Nev., for a period of four months, from April to July, 1914. The principal furnace dimensions are: Length, 132 ft. ½ in. at the skim-line level; average width, 18 ft., 10 in. at the skim-line level. The roof is 7 ft. above the skim-line level at the firing end. The average area in the uptake flue is 36 sq. ft., and the area above the skim line under the vulcatory arch is 24.3 sq. ft. Fig. 1 shows a diagrammatic plan and sectional elevation of this furnace. The furnace is equipped with two 400-b.h.p. Stirling waste-heat boilers set in parallel. California crude petroleum is used for fuel and has a specific gravity of 16.5° B., flashing in open test at 199° F. The oil is heated to about 200° F. in a steam heater before going to the burners, requiring about 9 b.h.p. per furnace day to heat it from the line temperature to the burning temperature. Measurement is made by oil meter, checked daily by reservoir readings. The oil is fed by gravity (34 lb. static pressure) to seven low-pressure blast burners of the Steptoe type (Fig. 2). The blast for these burners is supplied at about 40-oz. pressure by a motor-driven Connersville blower of 42 cu. ft. capacity per revolution. The air supplied by the blower through the burners for atomizing the oil amounts to about 10 per cent. of the theoretical air necessary for complete combustion of the oil. The remainder of the necessary air enters the furnace through the burner openings in the firing wall. No checker holes are provided, and the charge holes in the roof are equipped with slide gates and "dog houses? to minimize air leakages. The combustion of the fuel, as shown by gas analysis at the front of the furnace, is practically complete, the carbon monoxide in the gases being less than 0.5 per cent.

Jan 2, 1915

By Willard P. Ward

HAVING been engaged during the past year in the manufacture of ferro-manganese in a blast furnace, I have imagined that some further information on this subject might be of interest to that large number of members of the Institute who are engaged in the iron and steel industries. The great question of the economical production of good steel, ingot metal, or homogeneous iron (we scarcely know now what to call it) from good materials, and at reasonable prices, has, thanks to the intelligence and energy of a few American engineers, been successfully solved in this country. Nearly all first-class railroads, and many that would riot rank so high, have adopted the Bessemer rail. Martin boiler-plates are rapidly gaining ground, in competition with

Jan 1, 1877

By Willard P. Ward

Having been engaged during the past year in the manufacture of ferro-manganese in a blast furnace, I have imagined that some further information on this subject might be of interest to that large number of members of the Institute who are engaged in the iron and steel industries. The great question of the economical production of good steel, ingot metal, or homogeneous iron (we scarcely know now what to call it) from good materials, and at reasonable prices, has, thanks to the intelligence and energy of a few American engineers, been successfully solved in this country. Nearly all first-class railroads, and many that would not rank so high, have adopted the Bessemer rail. Martin boiler-plates are rapidly gaining ground, in competition with

By C. H. Herty

AN earlier paper on absorption of sulfur by the slag in the basic open-hearth furnace included a brief discussion of the absorption of sulfur during the melting period. The data available at that time showed that the amount of sulfur absorbed by the melting scrap was proportional to the sulfur content of the furnace gases, and the following statement was made: "The conclusion may be drawn from these results that if a gas entirely free from sulfur were used during the melting, any iron in direct contact with the gases would be completely, or nearly completely, desulfurized before it reached the bath proper." The experimental work discussed herein deals with absorption of sulfur by the melting scrap when fuels with both high and low-sulfur content were used. Before taking up the experimental work let us consider the process as a whole as to the "flow" of sulfur. The input of sulfur occurs in: 1, the hot metal charged; 2, the scrap; 3, the stone or lime charged; 4, the ores charged; and 5, the gas. Sulfur goes out of the furnace in the steel, the slag and the gas. The distribution of sulfur in the furnace depends on the sulfur concentration in each of these materials and on the equilibrium conditions between them.

Jan 1, 1926

By Ellis Clark

The greater portion of the brown ore in the vicinity of Easton, along the north slope of the Lehigh Mountain or Durham range of hills, is obtained from mines instead of from open cuts or quarries, as is the case in the ore-beds in the western part of Northampton County, in Lehigh County, and in Berks County. The reasons for this method of procedure are various, and the principal causes of the shaft and regular mine system of working being adopted instead of the open air cuts, are: First, the large amount of stripping that would be necessary, as the richer and more valuable portions of the ore do not appear to be found as near the surface as those in other portions of the Kittatinny valley; second, the occurrence of the ore in regular beds, interstratified with the clay, and, to a less extent, in pockets or erratic deposits, as is the case in the mines of Lehigh County; and third, on account of many of the mines being situated at the immediate base of the Lehigh Mountain, where the surface water would be in such large quantities as to be with difficulty handled, and where the subsequent caving in of the sides of the open cut would be almost certain to expose the gneiss rock, which is water-bearing, the large quantities of water coming from which would probably drown out the ore-bed. Shafts, and a regular system of gangways and mining are therefore required by the configuration of the surface, the depth of the deposits and their geological structure. The ordinary size of the shafts is about four feet square, but where an extensive plant of pumping machinery is required the size may be increased to eight feet by six, with two compartments for the hoisting and pump-shaft respectively. A man-way, consisting of ladders with rests at intervals of twenty or thirty feet, is comprised in the pump-shaft, the wire rope being used for purposes of ascent and descent only in exceptional cases, on account of accidents which

Jan 1, 1879

By C. C. Clark, J. S. Iwanski

The purpose of this investigation was to study mi-crostructural changes that take place in a commercial nickel-chromium-iron alloy, such as Incoloy "901," over long periods of time at temperatures up to 13 50°F and to correlate such changes with creep-rupture properties. of the alloy. In the course of the investigation, some microstructural changes were observed which correspond to microstructural alterations found in previous studies of Inconel "X." Microstructural phases have been identified in both alloys with the aid of electron and X-ray diffraction and an electron probe microanalyzer. The materials used in this investigation were from commercial heats of the following chemical composition: Pct Cr Pct Ni Pct Mo Pct Fe Pct Cb Incoloy "901" 12.51 43.67 5.72 Bal. -Inconel "X" 14.61 73.44 - 6.61 1.02 Pct A1 Pct Ti Pct Mn Pct Si Pct C Incoloy "901" 0.10 2.46 0.46 0.24 0.05 Inconel "X" 0.70 2.43 0.51 0.36 0.04 Long-term creep-rupture tests were conducted on Incoloy "901" at temperatures of 1000°, 1200°1 and 1350°F. A summary of these results is shown in Table I along with the results of a long-term creep-rupture test conducted on Inconel "X" at 1500°F. The heat treatments given the specimens are also shown in Table I. When the creep-rupture results on Incoloy "901" are compared with shorter-tertn data, there is no evidence of any undue deterioration of the creep-rupture strength with time, nor is the elongation decreased more than would be expected from the influence of time alone. INCOLOY "901" PHASE IDENTIFICATION Microscopic examination of the Incoloy "901" specimens reveals a dark etching grain boundary constituent in the specimen which was under test for about 11,500 hr at 1000°F. This grain boundary constituent was seen to increase in size as the test temperature was increased to 1200" and 1350°F, Figs. 1, 2, and 3. Simultaneously, an acicular structure of definite crystallographic orientation appears within the grains of the 1350°F specimen, Fig. 3. Under examination with the electron microscope, a fine precipitate is observed in the 1200 °F specimen. Fig. 4. It becomes considerably larger in the 2850-hr 1350°F specimen, Fig. 5. In a few areas the precipitated particles have been replaced by, or transformed to, small needles or platelets. After 7380 hr at 1350°F, Figs. 3 and 6, the needles are much larger and have replaced nearly all of the fine precipitate. X-ray diffraction studies detected the presence of hexagonal Laves phase and hexagonal n phase (Ni,Ti) in the 1350°F specimens, Table 11. Only the Laves phase was detected by X-ray diffraction in the 1200°F specimen and none was detected in the 1000°F specimen. In this latter specimen, however, the small quantity of precipitate in the grain boundaries (presumed to be Laves phase) precludes its detection by X-ray diffraction. Composition of the hexagonal Laves phase is not yet known, although its diffraction

Jan 1, 1960

By Louise B. Freeman

Kentucky for the first time in its oil history passed the 10 million barrel mark. Of the total 10,019,641 bbl., 8,262,516 bbl. were produced in Western Kentucky, and Union County surpassed all others, with 4,056,142 bbl., or 40 percent of all the production for the state. There were 930 wells known to have been drilled during the year; 510 in Western Kentucky and 221 in the gas-producing area of Eastern Kentucky.

Jan 1, 1946

By Hallet R. Robbins

KOREA, the ancient " Hermit Kingdom," is a peninsula jutting out from the coast of eastern Asia. By the natives it is called " Chosen," which, translated, means " Land of the Morning Calm." It lies between the Yellow sea and the Sea of Japan. On the north it is separated from Manchuria and the Russian province of Primorsk by the Yalu and Tiumen rivers ; on the south the Korean straits interpose a rough voyage of 120 miles to the nearest point in Japan. The entire country is situated between the parallels of 34° and 42° N. latitude. The surface of the country is made up of successive ranges of unglaciated mountains, separated by narrow, fertile, and more or less densely populated, valleys. Through all the obscure centuries of its history, Korea has succeeded in maintaining a monastic seclusion, over which, from time immemorial until the late Chino-Japanese war in 1894, China exercised a shadowy sovereignty. Although Korea had been forced into slight foreign contact previously, her first foreign treaty was signed with Japan in 1876. Under the restraining guardianship of China, the Japanese treaty bore but insignificant innovations for Korea; but when, in 1883, a treaty was made with the United States, the first of the western nations, a decade after the American gunboats, under Commodore Rodgers and Lieutenant Schley, forced their way up the Salee river, shooting daylight through the ancient walls and fastnesses, Korea awoke from her sleep of 4,000 years. The Korean peninsula suddenly became the arena where rival nations' enterprises and individuals met in fiercest conflict. Out of this struggle grew two singularly successful American

Jan 7, 1908

By Joseph C. Buchen

IN principle, production of salt from sea water is a simple operation. Sea water is trapped in ponds, the sun and wind cause evaporation of the water, and what is left is principally salt. Commercial production of solar salt, however, requires a careful consideration of many factors. Obviously, sufficient evaporation must take place throughout the making season to produce an economically adequate crop. Other factors are density of soil, contour of ground, height of ground above sea level, minimum dilution from fresh-water streams, and distance from market. Unfortunately, in the United States the localities of greatest evaporation, allowing for the other factors, are not the most suitable for the manufacture of sea salt by solar evaporation. The south end of San Francisco Bay most

Jan 1, 1937

By F. W. Luersson

High carbon, low phosphorus steel can now be made from pig iron containing 0.7 pct P or more, in a commercial sized open hearth furnace. No external heat is required for refining, and steel produced is identical with basic open hearth steel. THE classical Thomas process, which requires liquid pig iron containing over 11/2 pct P, yields a product relatively high in phosphorzs and nitrogen. Unless large quantities of recarburizers are added to the refined steel, the product is low in carbon content. Thus, the Thomas process is not well suited to American raw materials, and its product is often not acceptable according to the standards set by American industry. The shortcomings of the Thomas process have long been recognized; with the advent of low cost oxygen, studies were initiated to develop pneumatic processes which would conceivably overcome the inherent objections to Thomas steelmaking. Several such modified basic pneumatic processes have been tested experimentally in commercial trials during the past decade. Probably the most widely publicized of these developments has been the oxygen converter process as practiced in Austrial,2 and in Canada.8 n this process, oxygen is substituted for air and introduced above the liquid bath in order to increase the heat available to the metallurgical system. This avoids the need for high phosphorus raw materials and gives a product low in nitrogen. In this process, the phosphorus content in the final product depends, to a considerable extent, on the total amount of that element in the burden. The rotary furnace4 which is now in commercial operation at Domnarvet Steelworks, Sweden, is producing low phosphorus steel from iron containing 1.8 to 2 pct P. One or more early slags are removed and by this means high carbon steels of open hearth quality can be produced. At this stage of development there is some question as to the applicability of the rotary process to large heats. Another development has been the use of oxygen in combination with either steam6 or carbon dioxide yn the basic bessemer, thus avoiding the introduction of nitrogen gas into the refining system and giving a product relatively low in nitrogen content. A double slag process has been used in Europe7 in conjunction with a regular Thomas converter, by means of which it is possible to obtain a phosphorus content in the product approaching that obtained in basic open hearth steels. The Turbo-Hearth process:' which uses the side blowing principle so as to produce low nitrogen steel from normal American pig irons, has been developed experimentally in this country. A process fitted to U. S. raw materials All of the preceding processes, with the exception of the rotary furnace, suffer from the common shortcoming that they cannot be adapted to the production of high-carbon, low-phosphorus steels unless large proportions of recarburizers are added. In 1947, a program was initiated by the Inland Steel Company1' to study an oxygen steelmaking process specifically designed to utilize the full range of phosphorus analyses encountered in American pig irons and to give finai products with phosphorus and nitrogen contents comparable to steel produced by the basic open hearth process. Some of the objectives of the proposed process are: 1) the process should be able to accommodate molten pig iron conta;rl;rrg up to 1 pct P., 2) sne process should be subject to close control of carbon analysis, 3) the process should be capable of producing high carbon

Jan 1, 1958

By F. F. Poland

The purpose of this paper is to describe the recent applications and improvements made in the process and equipment for the recovery of metallic zinc from secondary metals by means of high temperature electric resistor furnace distillation. The process and high temperature furnace, as developed by Revere Copper and Brass Incorporated, Research and Development Department, was described in a previous paper. † Since the publication of that paper the process and equipment have been licensed to others. Consequently its field of application has been expanded, particularly for the treatment of scrap brass, galvanizers dross and scrap zinc. Other applications are being considered, particularly the melting of metallic titanium and special alloys requiring a controlled atmosphere. Consideration is also being given to modification in design that would allow the melting of copper cathodes for the production of oxygen-free and electrolytic tough pitch copper shapes without the necessity of blowing and poling. In the design of a furnace for melting copper cathodes it is intended that the fundamental principle of charging the solid material into a large pool of molten metal through a double door charging vestibule as shown in Fig 3 of the previous paper, † would be adhered to and, in addition, either dehydrated and desulphurized producer gas or commercial nitrogen, that is, approximately 96 pct nitrogen, 2 pct hydrogen 2 pct CO, also dehydrated, would be used to provide a protective atmosphere for the resistors and to flush out more soluble gases from the molten copper. The operation of a small unit producing approximately 1000 lb of copper per hr has shown that the commercial nitrogen will allow the production of tough pitch electrolytic copper when the metal is transferred from the meltdown unit contemplated to a special type induction unit where the oxygen absorption and temperature can be controlled. Standard practice in treating low grade scrap brass has been to oxidize the zinc by blowing air through the molten metal. This operation results in the recovery of approximately two-thirds or less of the zinc content of the brass in the form of an impure zinc oxide having only a fraction of the value of the zinc in metallic form. The balance of the zinc is lost to slag, fume and drosses. Fig 1 shows the revised flow sheet of the process for the treatment of scrap brass. For this application and as shown on the flow sheet a low frequency induction furnace has been substituted for the Wilkins-Poland type as a melting unit. This type of furnace has been found the most suitable for the purpose as will be shown by the following discussion. Serap Brass The melting of refinery scrap brass preparatory to distillation presents a melting problem quite different from the usual melting of brass mill scrap for recasting because refinery scrap is a heterogeneous mixture of alloys each having different melting and boiling points, and coated with a variety of corrosion products and foreign materials. In addition, brass and copper plated pieces of sheet iron, stainless steel, ceramic materials, and others are present that do not melt except at temperatures above the boiling point of the liquid bath. In the previous paper it is noted that difficulty was encountered in the melting of refinery grade scrap brass without excessive loss of zinc by volatilization and that 5 to 10 pct razorite flux was used to alleviate this condition. While this flux was successful in preventing the excessive loss of zinc by volatilization it interposed a low heat conductivity layer between the source of heat and liquid charge and resulted in lowering the melting rate of the furnace. This same problem presents itself in all types of furnaces in which the metal is heated by radiation and conduction from above the charge. It has been found in melting this type material that the melting rate per hour or per square foot of hearth area

Jan 1, 1950

By Jean Bonnemaison

Societe Miniere & Metallurgique de Penarroya Noyelles-Godault works are located in the northern part of France. The complex includes a lead smelter, a zinc smelter, shops for production of manufactured products and all necessary general services. The zinc smelting complex described in this paper was designed in 1959 to replace an old horizontal retort distillation furnace and was first operated in May 1962. It includes: - a sinter plant producing the zinc sinter for the Imperial Smelting furnace : zinc, lead and bulk zinc-lead concentrates are sintered on a Dwight-Lloyd machine with a working area of 80 sq.m. Cadmium sludges are treated by the wet method in a separate plant for recovery of cadmium. Sulphur dioxide contained in gases goes to a gas washing tower and is subsequently made into sulphuric acid in a plant with a capacity of 550 m.t. per day. - a smelting plant where the process developed by Imperial Smelting Processes Ltd. is applied : the blast furnace which was modified in 1967 has an area of 17.5 sq.m. at the tuyeres level and a section of 24 sq.m. at the top of the shaft. It has a theoretical zinc capacity of 100,000 m.t. per annum. Air blast is heated by means of covers up to the theoretical temperature of 950ºC. Zinc produced is either directly cast into slabs for sale as standard 'good ordinary brand' zinc, or sent to a refining plant where the New Jersey process designed to produce 'special high grade' zinc is in application. Mixes of zinc containing various amounts of lead, cadmium or aluminum are prepared to customer specification in a mixing plant.

Jan 1, 1970

By R. A. Pallanch

IN his recent paper, "The Controversial Art of Flotation," (Mining Technology, March, 1944) E. H. Rose states that "flotation is a science in so many variables that only art can blend them." This statement is apt. It contains meat. In other words, a valid scientific reason is behind every flotative effect. Some of these reasons we understand, but much the greater number of them still escape us. This does not prevent us from "going places," as familiarity and experience with the problems result in an increasingly intelligent and artful handling of these effects. Hypotheses are built up by the individuals concerned to explain certain happenings. Many of these hypotheses have to be abandoned when placed under the glaring scrutiny of actual trial. A few survive the severest of tests, come through unscathed, and are elevated to the rank of theories, something susceptible of certain chemical and physical explanation, under the conditions of the particular plant concerned. If these theories continue to hold water under all the variations existing in most milling plants, they gradually become accepted as facts in the minds of the plant operators. But-and here is a big BUT-these so-called facts may fall down completely in another plant working under an entirely different set of conditions. In other words, each plant tends gradually to build up its own facts, which may or may not be facts at another operation.

Jan 1, 1945

By George H. Cook

At first sight this subject seems to belong to pure theoretical geology, but examination will soon show that it has important practical and economic interest to the mining engineer. The conclusion that all the northern portions of our country, as well as of the eastern continent, have, in the later periods of geological history, been covered with a thick bed of ice, is now accepted by geologists. This bed of ice, except in its greater magnitude, was like the modern glaciers of the Alps, and other mountains which extend above the line of perpetual snow. The marks it has left upon the surface show that it was comparatively thin on its southern edge, but that its thickness was much greater a little further north, and that it was several thousand feet thick at its kenviest parts. This variation of its surface would give it a descending slope towards the south, and cause the mass of ice, like a semifluid substance, to move in that direction,

Jan 1, 1879

By W. D. BRENNAN

AS a rule the thoughts of engineers are more often directed toward the mechanical and physical conditions of mining practice than they are toward the disposition and the marketing of the product. This, I think, has been true of the coal industry to the present time not only among the engineering force but also generally true of operators. There has been a tendency to place the sales department in a rather secondary position; for a great many years there was a greater demand for coal than the supply would meet, so it was only necessary to increase production: either by expansion of operating mines, or opening new mines of greater capacity. While the production of coal is still a highly important phase of the industry, its enormous development throughout the country, the great advance in fuel, efficiency and economy, and the discovery of new reserves of competitive fuels have combined to create a buyers' market and force the present-day attention upon merchandising in modern ways. A buyers' market has a natural tendency to develop the keenest competition, frequently unscrupulous and nearly always profit-wrecking. Under such conditions bad practices are bound to grow and to extend until the industry is wrecked, or until wiser heads get together to reduce or eliminate unfair methods of competition. This is not so recent a condition as one might believe.

Jan 1, 1931

By W. E. Coxe

In 1857 the Philadelphia and Reading Railroad Company, whose main line extended from Philadelphia to Pottsville, Pennsylvania, with branches into the coal regions of Schuylliill County, made a contract with the Fairmount Rolling Mill, at Philadelphia, for the rerolling of some four thousand tons of iron rails. The essential features of the agreement were that the old rails should be piled with puddled iron and rolled into flats for the rail pile, which latter was • to be of a section seven inches square, and after being heated, and reduced, by rolling, to a bloom of a section about fire inches by six inches, was to be reheated, before being finished into the rail of the T pattern, four inches high, weighing sixty-four pounds per yard. Great care was exercised in the execution of this contract, and the rails being distributed over all parts of the road, gave general satisfaction by their excellent wear. Five years afterward, the principal proprietor and manager of the Fairmount Rolling Mill was elected President of the Reading Railroad, and very many of the rails made under his supervision were still in use in the tracks of the company, of which he had just assumed the management. His first efforts were, therefore, directed to the procuring of more rails of the same quality wherewith to replace those worn out. Here he encountered some trouble, makers refusing to bid because of the details in the specification, the required reheating being the objectionable feature, for which it was generally intimated they would not be sufficiently remunerated for the increased labor, extra coal consumed, and the changes necessary from the established methods of working. Most of the new rails were, therefore, bought, and the old rails rerolled without regard to any particulars as to the manner of piling, heating, etc., each manufacturer furnishing what he deemed the best article possible for the money. As a consequence, rails of all imaginable grades were placed in the tracks, some giving out in six

By W. E. C. Coxe

IN 1857 the Philadelphia and Reading Railroad Company, whose main line extended from Philadelphia to Pottsville, Pennsylvania, with branches into the coal regions of Schuylkill County, made a contract with the Fairmount Rolling Mill, at Philadelphia, for the rerolling of some four thousand tons of iron rails. The essential features of the agreement were that the old rails should be piled with puddled iron and rolled into flats for the rail pile, which latter was to be of a section seven inches square, and after being heated, and reduced, by rolling, to a bloom of a section about five inches by six inches, was to be reheated, before being finished into the rail of the T pattern, four inches high, weighing sixty-four pounds per yard. Great care was exercised in the execution of this contract, and the rails being distributed over all parts of the road, gave general satis¬faction by their excellent wear. Five years afterward, the principal proprietor and manager of the Fairmount Rolling Mill was elected President of the Reading Railroad, and very many of the rails made under his supervision were still in use in the tracks of the company, of which he had just assumed the management. His first efforts were, therefore, directed to the procuring of more rails of the same quality wherewith to replace those worn out. Here he encountered some trouble, makers refusing to bid because of the details in the specification, the required reheating being the objectionable feature, for which it was generally intimated they would not be sufficiently remunerated for the increased labor, extra coal consumed, and the changes necessary from the established methods of working. Most of the new rails were, therefore, bought, and the old rails rerolled without regard to any particulars as to the manner of piling, heating, etc., each manufacturer furnishing what he deemed the best article possible for the money. As a consequence, rails of all imaginable grades were placed in the tracks, some giving out in six

Jan 1, 1877

By Cecil H. Desch

THE progress of metallurgical practice and the demands made by the engineering industry on our foundries and mills have made the crystalline structure of metals a subject of far more than academic interest. Metals and alloys are made up of crystals. Even if we accept the view, so ably maintained by some metallurgists, that the crystals are separated from one another by an amorphous layer, it remains true that all but a very minute fraction of any metallic mass is crystalline. The conditions which affect the growth of crystals are therefore of importance in metallurgy. It is not only castings whose properties depend on the arrangement of their crystals, for the more we learn of the behavior of forged, rolled and drawn metals, the more certain it becomes that it is profoundly influenced by the size and arrangement of the crystals in the original ingot, deter- mining a structure which may persist in a modified form through a long series of mechanical operations and annealings. This is mainly due to the concentration of much of the impurities in the last portions of the liquid to freeze, so that the boundaries between single crystals or groups of crystals are marked out by a zone of segregated material, differing in properties from the mass, and offering a barrier to diffusion and equalization of composition throughout the whole. The importance of this fact has been fully recognized by steel manufacturers, who have to deal with ingots which are sometimes very large, and are cast at a high temperature, containing impurities which have a marked effect on the properties even when present in very small quantity. For this reason the Iron and Steel Institute has set up a committee to examine the whole question of the heterogeneity of steel ingots,(l)f and a report has been issued, containing an account of the structure of 16 ingots, ranging in weight from 15 cwt. to 172 tons, each of which was sectioned and examined by chemical analysis and by etching. A valuable body of data concerning segregation has thus been collected. The work of the committee is being prosecuted with great activity, and at the same time researches are in progress to determine the physical

Jan 1, 1927