Search Documents

Lester Guttman (General Electric Research Lab-boratory)—Seybolt has measured the thermodynamic activity of silicon in dilute solution in a iron. The anomaly which appears at 800 °C in the approximate range 1 to 6 wt pct Si is most naturally attributed, as Seybolt has done, to the existence of a region of

Jan 1, 1960

By S. R. Goodman, Hsun Hu

A study has hem made of the formation of annealing textures in an 18-8 austenitic stainless steel (Type 304L) from various deformation textures obtained by rolling at different temperatures. When the deformation texture is a mixture of the ferritic type and the brass type owing to the pres -ence of both martensitic ferrite and retained aus-tenite in the specimen, recrystallization takes place by the growth of the existing austenite phase. In a previous report,' it was shown that the rolling texture of austenitic stainless steel (Type 304L) changed gradually from the brass type to the copper type with increasing temperature of deformation above 200°C. These changes are similar to those in high-purity silver2,3 and electrolytic copper;4 a brass-type texture is favored at low rolling temperatures, whereas a copper-type texture is favored During the course of rolling -texture transition from the brass type to the copper type, the subsequent recrystallization textures change accordingly. The orientation relationship between the annealing textures and the various rolling textures, being consistent with previous observations on various fcc metals, can be described as [Ill] rotations of approximately 25 to 40 deg. Carhide precipitation may influence the annealing textures. at high rolling temperatures. Furthermore, the annealing textures in high-purity silver5 and electrolytic copper4 were found to depend entirely on the prior deformation texture. From a copper-type rolling texture a strong cube texture will form upon recrystallization, whereas from a brass-type rolling texture the annealing texture will be quite different from the cube orientation. In an earlier comm~nication,6 the formation of a strong cube texture in 18-8 austenite stainless steels (Types 304 and 304L) was reported briefly by the authors. The present paper constitutes the results of a complete study of the annealing textures obtained from a

Jan 1, 1965

By A. L. Holley

The application of scientific methods to the investigation of natural laws and to the conduct of the useful arts which are founded upon them, is year by year mitigating the asperity and enlarging the outcome of human endeavor. More notably, perhaps, are these the facts in that system of productive and constructive arts of which engineering is the general name. In metallurgical engineering especially, within the period of our own recollection, how rapid has been the rate and how wide the scope of progress: the scientific discovery and mining of metalliferous veins; the economical separation and reduction of ores of every grade; the production and regulation of high temperatures; the varied improvements in the manufacture of iron, in saved heat and work, in uniformity and range of products; and, most important of all, the creation and the utilization, to be counted by the million tons a year, of the cheap constructive steels. Wonderful as this range and degree of development may appear to the public eye, the close and thoughtful observer must, nevertheless, conclude that neither the profession nor the craft of engineering may congratulate themselves too complaisantly, but that they should rather acknowledge to each other the embarrassing incompleteness of the union between engineering science and art. There is a small school of philosophers whom we may designate as original investigators, men who come close to nature, who search into first principles, and who follow that scientific and therefore fruitful method by which the relations of matter and force are discovered, classified, and brought within the reach of practice. These wonderful men do not indeed create the laws of nature, as they sometimes almost seem to, but they go up into the trembling mountain and the thick darkness and bring down the tables upon which they are written.

By V. N. Krivobok

THE study and use of low-carbon manganese steels have been curiously neglected in the general history of developments in alloy steels. Hadfield1 made an extensive study of manganese-iron-carbon alloys about 1886, which culminated in the wide application and use of Hadfield austenitic manganese steel. His alloys were nearly all high in carbon, as compared with the steels discussed in this paper, and he found a marked tendency towards brittleness in the alloys of medium and low manganese content, that is, below 7 per cent. manganese. As a result, there has been a widespread prejudice against the use of manganese steels containing between 1.0 to 3.5 per cent. manganese with comparatively low carbon. Steels of this composition have never been studied adequately in comparison with other alloy steels, and have had little use in practice. In a very recent paper by Sir Robert Hadfield2 the following statement appears: ?. . . manganese-iron alloys with little or no carbon do not seem to offer any practical employment; they only become valuable in the presence of quite high percentages of carbon, 0.90 to 1.50 per cent." The results of the present investigation are so contrary to the findings of Hadfield that the writers feel fully justified in presenting the preliminary report incorporated in this paper.

Jan 1, 1927

By Harvey Brooks

Jan 1, 1963

By P. A. C. Wilson

Instantaneous outbursts of carbon dioxide in coal mines have occurred in Germany only in one part of the Waldenburg-Neurode mining district.' This mining region comprises the northeastern fold of the "Innersudetian" coal basin. The basin (Fig. 1) is in the form of a geologic trough approximately 60 km. (37 miles) long and 30 to 35 km. (19 to 22 miles) broad and is enclosed on three sides by ancient truncated mountain ranges—the Riesengebirge, the Bober-Katzbachgebirge and the Eulenge-birge. Only the southeastern part of the trough is not enclosed by mountains of older rock formation. The floor of the basin before the building up of the coal measures was formed on the western, northwestern and northeastern borders by the material from Archean rocks (gneiss and mica schists); in the northern part over this was deposited the Silurian formation. The carboniferous period is represented both by the Lower ("kulm") and Upper Carboniferous, with an unconformity between the stages; that is, the kulm was tilted up and partly eroded before the Upper Carboniferous was deposited. The kulm is a salt-water formation (with marine fauna) but Upper Carboniferous rocks are nonsaline water deposits, with fresh-water flora only. The Lower Silesian coal measures were thus formed in a lime basin fed by the running water coming down from the mountains. As already indicated, the bottom series of the Upper Carboniferous formation, termed "Waldenburg strata" were laid down unconformably on the Lower Carboniferous. Over the Waldenburg strata there are the "Weisstein strata," an intermediate barren stage without coal beds, 400 to 500 m. (1300 to 1600 ft.) thick. Another unconformity followed, which is overlain by the '(Saarbrucken" series, which contain the upper coal measures, and the ('Ottweil" strata. In the last named, it is only on the southwestern fold that beds of coal are developed.

Jan 1, 1931

Jan 1, 1881

By C. O. Burgess, W. D. Forgeng

DESPITE the increasing interest in and the technical importance of iron-chromium-manganese alloys, very little published information is available regarding their constitution. F. M. Becket's paper1 in 1930 represents the first correlated effort in the field of these alloys. The paper served particularly to draw attention to the commercial possibilities of iron-rich alloys containing chromium and manganese in balanced proportions. The duplex structure of alloys within the commercial range was briefly discussed, but exposition of their structural constitution was necessarily limited because the physical properties and corrosion resistance of the alloys were the main subjects of the paper. Both prior to and following the publication of F. M. Becket's paper, and at his instigation, an extensive investigation of the constitution of iron-chromium-manganese alloys of commercial purity was in progress at the Union Carbide and Carbon Research Laboratories, Inc. The present paper is based on the results of that investigation. In the last few years, investigations covering various portions of this alloy system have also been made in Europe. W. Koester briefly mentioned the effect of annealing on chromium-manganese steel2 and later3 constructed approximate sections of the iron-chromium-manganese equilibrium diagram. M. Schmidt and H. Legat14 even more recently studied this system, and their article and conclusions are of interest as representing an entirely independent study of a number of iron-chromium-manganese alloys. Koester's sections are shown in Fig. 1. The figures summarize the effect of manganese additions to iron alloys containing 5, 10, 15 and 20 per cent Cr as well as the effect of increasing chromium content on iron alloys containing 3, 8, 20 and 30 per cent Mn. These diagrams, within their composition limits, substantiated in some measure the results of our investigation. However, in our work some differences as regards the position of the mixed alpha-gamma fields were found as compared to Koester's work, and we were able to detect the presence of

Jan 1, 1938

By Leonard Grimshaw

DIFFUSION Of carbon from gases into iron has been the object of much research, because of its long recognized importance in carburizing processes, but the direct diffusion of carbon from steel into iron has received relatively little attention. Because of the increasing use of clad metals in industry, direct diffusion from steel into iron is becoming of practical importance. Therefore, the object of this investigation was to study the diffusion of carbon from several different kinds of steel directly into relatively pure iron, realizing that elements in the steels other than carbon might influence the rate of carbon diffusion. The previous work on diffusion of carbon into iron has been consider-able, and includes many reports in foreign languages. This work has recently been well reviewed by Mehl1 and Krynitsky,2 and the reader is referred to their excellent bibliographies.

Jan 1, 1937

Jan 1, 1969

Part 1. Coal Part 2. Industrial Minerals

Jan 3, 1977

Jan 1, 1897

By Paul M. Tyler

MUCH information concerning pegmatites which was thought to be true a few years ago has been proved false, and what is now actually known about some pegmatites is not true of many others. The erratic and seemingly unpredictable structure and variable composition of this class of mineral deposits has been widely emphasized. Even parts of the same pegmatite body exhibit marked differences in texture, mineral composition, width, and attitude. Constructive geological thinking in respect to pegmatites now aims to establish general laws rather than to stress the confusing diversity of features having no special economic significance.

Jan 9, 1953

By Paul Billingsley

Introduction. THE Georgetown mining district is located in Deerlodge county, Mont., about 20 miles west of Anaconda. It lies along the divide between the headwaters of Warm Springs creek, draining eastward, and Flint creek, flowing west and north through the Philipsburg valley. The actual divide is formed by Cable mountain, a narrow ridge running north and south, terminating to the south in low hills overlooking Georgetown lake, and to the north in a high, rugged plateau that falls off to the west to the wide valley of Flint creek. Oil the eastern, or Warm Springs, slope of Cable mountain is the Cable mine, with the Hidden Lake mine a few miles north. On the western slope is the Southern Cross group, with smaller mines, the Twilight, Cincinnati, Red Lion, and Big Bill, at intervals to the northward. The Georgetown mines lie in the hills south of Cable mountain; the Philipsburg mines, of which the Granite Mountain, Bimetallic, Hope, and Trout are the chief, form a separate group to the north, overlooking Flint Creek valley and Philipsburg. (See Fig. 1.1) The region ranges in elevation from 5,000 to 9,000 ft. It is, with the exception of the lower valleys, well timbered with small fir and pine, although Cable mountain and the higher summits to the northward rise slightly above timber line. The main valleys have the smooth contours of glaciation, and their mouths are frequently choked with morainal deposits.

Jan 9, 1913

By E. W. Davis

I . OPERATING TESTS 1. CHARACTER OF ORE UNDER INVESTIGATION On the eastern end of the Mesabi Range, in Northern Minnesota, is a large formation of siliceous rock which contains bands and fine grains of magnetite . The magnetite comprises about 35 per cent. of the rock. Fig.. 1 show's graphically that the tonnage of minus 200-mesh material produced varies directly with the tonnage fed to the mill. There is undoubtedly some limit to this relation, but there seems to be no indication of it at 18 T. per hr. Some of the conclusions drawn from this test are that: (a) The ball-mill is naturally a machine of very large capacity; (b) if it is not possible to deliver a large tonnage of original feed to the mill, a closed circuit should be provided so that the mill may crush its own oversize.

Jan 2, 1919

By W. E. Remmers

The defect in wire known as "cuppiness" has appeared and disappeared from time to time but the exact cause of its appearance or disappearance has not heretofore been known definitely. This defect is not limited to one particular metal or alloy but seems to be found at various times in all of the materials that are drawn into wire. Fig. 1 represents cuppy wire made from an aluminum alloy and Fig. 2 illustrates copper wire that became cuppy in drawing without intermediate annealing. Differences of opinion are current among the manufacturers of wire and in the literature (see bibliography at end of paper), some believing that the source of the trouble lies in segregation in the wire rod, oxides, sulfides, slag, etc.; others that the trouble is created by an unevenness of stress distribution across the section of the wire, usually thought of as being a function of die shape. All of the published work is of a qualitative rather than a quantitative nature. With this in mind, it was deemed advisable to make a study of the shape of the wire-drawing dies, as well as the oxygen content of the copper to be drawn. Experimental After several methods were tried, it was found that by studying the contour of the butt-end of the rod after drawing a measure of the "working" across the section of the wire could be made. The butt-end of the annealed rod was not sheared but was sawed off. The end was then smoothed with a fine file so that the plane of filing was perpendicular to the drawing axis. It is to be noted that this method is not an absolute measure of the distribution of cold working but is a very good indicative means of studying comparative values. The method of examining a tension break in wire was found to be the most sensitive in detecting cuppiness. Other methods, such as microscopic examination of longitudinal sections, X-ray radiographic studies, etching away of outer layers with nitric acid, and fracture by bending, can all be used to identify cuppy wire but the tension break will give the fracture characteristic of cuppiness before any of the other methods can

Jan 1, 1930

By M. Baeyertz

SINCE 1915 many papers and books have covered industrial applications of X-rays from various angles. Two of the more recent are a paper by Fink and Archer1, which describes in detail the technique of radiography, and a paper by Clark2, which embraces the whole field of X-ray metallography. This paper, therefore, is confined to work of the X-ray Laboratory of the Western Electric Co., which naturally divides into two categories: radiography and diffraction patterns of various types.

Jan 1, 1930

Jan 1, 1924