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By H. Morgolin, M. A. Greenfield, P. A. Farrar

In attempts to correlate mechanical properties with microstructure, it is desirable to determine the effect of ß grain size. Determination of 6 grain size is not a problem where a has precipitated at ß grain boundaries. However, in alloys which have been processed to produce an equiaxed a +ß structure the ß grain size is difficult to determine because ß grain boundaries do not etch. The ß grain size can sometimes be laboriously determined by searching for grains which have some a! outlining the 6 grains. This difficulty of ß grain size determination in equiaxed a + ß alloys can be overcome by heating below the ß transus temperature for a short time and water quenching. Fig. 1 shows the starting equiaxed a + ß structure of the Ti-5.25A1-5.5V-0.9Fe-0.5Cu alloy used in this investigation, and Fig. 2 shows the microstructure of the same sample water-quenched after heating 1 min at 1675"F, which is 25°F below the 0 transus. The heavily etched microstructure consists of some equiaxed a! in a structure showing considerable amounts of transformed ß. The ß grain

Jan 1, 1969

Who's Who in Mineral Engineering - The 1979 Directory of the Society of Mining Engineers of AIME

Jan 7, 1979

By B. A. Wilcox, A. H. Clauer

DURING the course of an investigation on the high-temperature creep behavior of TD Nickel* (Ni + 2) vol pct ThO2), it was observed that the creep fractures were similar in appearance to low-temperature ductile fibrous fractures and creep ruptures by cavitation. Microfractographs of fibrous ruptures are typically characterized by a dimpled appearance, with second-phase particles frequently found near the bottom of the dimples.'-4 These somewhat resemble creep ruptures by cavitation, in that fracture occurs by void formation, with the subsequent growth and final merging of the voids to form a complete fracture.' It is the purpose of this communication to describe the creep fracture of TD nickel and suggest a mechanism for the rupturing process. The discussion is relevant to material crept to fracture in vacuo at a constant stress of 18,000 psi, over the temperature range 900" to ll00°C. The material used in this investigation was 1/2-in.-diam bar stock supplied by Du Pont, contain- ing 2.3 vol pct Tho2. The final fabrication treatment consisted of -95 pct reduction by swaging followed by a 1-hr anneal at 1000°C. Transmission and replica electron microscopy revealed that the material had a fibered structure with a transverse grain size of -1 µ and a longitudinal grain size of 10 to 15 µ. Selected-area diffraction indicated that the fiber axis was parallel to (00l), in agreement with the results of Inman et a1.6 The thoria particle size varied from 80 to 1000Å, with an average size of 400Å, and the mean particle spacing was about 1200Å. The remarkable structural stability7 was confirmed by annealing for 6 hr at 1300°C (about ' 0.9 the absolute melting point). Transmission electron microscopy revealed that the only structural change was a slight decrease in dislocation density. Furthermore, recrystallization or grain growth during creep has not been observed. All specimens were annealed in vacuo at 1300°C for 3 hr prior to creep testing. The following times to rupture were obtained for vacuum creep tests at a constant stress of 18,000 psi: 900°C, 854 hr; 930°C,

Jan 1, 1965

By HERBERT G. MOULTON

FROM prehistoric times to our own day man has struggled against extremes of climate. Human life, originating in semi-tropical or temperate areas, was unable to progress into the northern latitudes until fire was discovered and some form of clothing provided. It was found possible to maintain life even in the hottest parts of the tropics, but only at a great sacrifice of comfort and efficiency compared with the more temperate zones, or in cooler areas with the protection of clothing and artificial heat. It was no accident, but the natural result of climatic conditions, that efficiency became the greatest and civilization the most advanced in areas where the natural climate was favorable, or in cooler zones where protection against severe cold could be se-cured by relatively simple methods of conserving or producing heat.

Jan 1, 1933

By Wallace E. Pratt

TO SERVE their primary function of balancing supply with demand. crude-oil prices must not only return full cost plus a reasonable earning to the efficient producer but they must also offer an additional reward to stimulate exploration sufficiently to maintain adequate reserves. High prices increase the volume and efficiency of exploration; low prig e- -Idle exploration. Over the last decade average prices for crude oil have been much lower than for the proceeding ten years, and lower even than the average over the life of industry. Under these circumstances no one should be surprised to learn that over this same recent period of discovery of new oil fields has also lagged and fallen below its average level for the previous decade. Crude oil prices have been too ion to support the required activity in wildcatting.

Jan 1, 1941

By F. D. Richardson

STAFF: Editor, Gerhard Derge Carnegie lnstitute of Technology Schenley Park Pittsburgh, Pa. 15213 Editorial Assistant, M. A. Redmerski Production Editor, Otto T. Johnson THE METALLURGICAL SOCIETY: Jack H. Scoff, President; Richard C. Cole, Past-President; Harold 0. Emerick, President-Elect; Ralph L. Hennebach, Treasurer; Robert W. Shearman, Secretary; Donald A. Parks, Assistant Secretary; Leslie S. Wilcoxson, Assistant Secretary. PUBLICATIONS COMMITTEE OF THE METALLURGICAL SOCIETY: R. E. Lund, Chairman; T. E. Dancy, H. O. Emerick, P. R. Gouwens, R. E. Grace, J. H. Jackson, H. H. Johnson, A. E. Lee, Jr., R. R. Nosh, R. D. Pehlke, and Paul Queneau. Review and selection of manuscripts is under the supervision of the following Publications Committees: Extroctive Metallurgy Division: R. E. Grace, Choirmon; G. M. Bell, D. W. Bridges, J. M. Cigon, G. W. Heoly, T. A. Henrie, R. D. (Holli-doy, C. E. O'Neill, C. S. Somis, A. W. Schlech-ten, and Charles Shull. Iron and Steel Division: R. D. Pehlke, Choirmon; T. P. Floridis, Arnulf Muon, G. R. St. Pierre, E. T. Turkdogan, L. H.Von Vlock, and J. M. Uys. lnstitute of Metals Division: H. H. Johnson, Jr., Chairman; J. B. Clark, Vice Choirmon; M. R. Achter, G. F. Bolling. J. O. Brittoin, G. P. Conard, II, R. S. Davis, L. A. Girifolco, G. T. Hohn, J. P. Hirth, L. Himmel, G.T.horn, George Krauss, J. D. Livingston, R. D. Manning, H. M. Otte, S. V. Rodcliffe, R. E. Reed-Hill, H. C. Rogers, E. ScaIa, O. Sherby, M. T. Simnad, G. R. Speich, E. A. Steigerwald, R. A. Swolin, W. A. Tiller, W. R. Upthegrove, J. B. Wagner, Jr., Derek Wolton, H. W. Weart, W. W. Webb, and D. Published seven times yearly in February, March, April, June, August, October, and December by the American lnstitute of Mining, Metallurgical, and Petroleum Engineers, Inc., 345 East 47th Street New York, N. Y. 10017. Telephone PLAZA 2 -6800. Subscription $30 per year for non-AtME members m United States and North, South, and Central America; $32, foreign; $7.50 for AlME members Single copies, $6.00, single copier foreign, $6.50. The AiME is not responsible for any statement made or opinion expressed in its publications . . . Copyright 1964 by the American Institute of Mining, Metallurgical, and Petroleum Engineers, Inc. . . . Registered cable address, AiME New York Indexed in Engineering Index, Industrial Arts Index, and Chemical Abstracts. Second dost postaas poid ot New York, N. Y.,ond Ann Arbor, Mich. Volume 230, Number 6.

Jan 1, 1964

Jan 1, 1967

By R. E. Hummel, J. W. Koger

IT is generally accepted that the martensitic start temperature (Ms) can be determined by resistivity measurements and is that temperature where the resistivity vs temperature curve on cooling first deviates from a straight line.1-4 Both Titchener and ever' and pops5 have used resistivity measurements to follow the martensitic transformation in b1 Cu-Zn and ternary Cu-Zn-based b-phase alloys, respectively. Actually because of the nature of their measurements the temperature of minimum resistivity (M) was used by these authors to determine "Ms" . Also, due to experimental difficulties in detecting M, with resistivity measurements, Pops and Massalski 8 determined M, by optical microscopy. The present communication is concerned with high-precision, low-temperature resistivity measurements which reveal a definite M, temperature which differs from the temperature of minimum resistivity (M). It is also shown that M is merely the result of the geometry of the percent-transformation curve and the temperature coefficient of resistivity of the alloy. In other words, it will be demonstrated that M has no apparent significance (except that it denotes a temperature at which some percent of martensite can be detected in a given alloy). Alloy specimens were made by melting 99.999 pct Cu and 99.9999 pct Zn in sealed and evacuated quartz tubes and homogenizing them at 601PC for 300 hr. After the alloy was cold-rolled into foils suitable for resistivity measurements, it was quenched in ice water from 871PC. The chemical analysis showed a zinc content of 38.8 wt pct. The cooling rate during the martensite transformation was 1°C per min and was controlled with a thermistor. Electrical resistivity measurements were made using a K-3 type potentiometer; the reproducibility of the resistivity values was better than 0.03 pct. Temperatures were measured with a thermocouple to an accuracy of better than 0.2° C. Fig. 1 shows the resistivity vs temperature curves of the martensitic transformation in B1 Cu-Zn for both cooling and heating. The starting point of the martensitic transformation (M,) was taken as that

Jan 1, 1968

Jan 1, 1968

By J. J. Forbes

Probably the newest thing in mining safety, or safety for mines, is the apparent dissatisfaction on the part of the mineral industries, as represented by both management and labor, and the general public of the Nation, with the safety record of the mining industry. This is reflected by published comments and papers in the technical press;1-8 in labor periodicals, 10 11 in popular journals and periodicals,12 13 and in the daily press; also by discussions of the Safety Committees sponsored by the National Safety Council, 9, 14-15 the American Mining Congress, 1, 16 the American Institute of Mining and Metallurgical Engineers, 2, 4 the Mine Inspectors' Institute of America,6,8,17,18 the Coal Mining Institute of America, 5, 19, the American Standards Association, and others.20,21

Jan 1, 1949

By Oliver Bololes

UNDER the able leadership of Samuel H. Dolbear, the Committee on Nonmetallic Minerals furnished a program of sixteen papers comprising three sessions. An outstanding accomplishment in technology presented at the first session by Benjamin L. Miller and C. H. Breerwood is the application of flotation to the purification of limestone used in cement manufacture. In place of selective quarrying to provide high-grade raw material, the quarry-run stone is pulverized and treated in froth flotation cells for removal of free silica and mica. Some advantages are cheaper quarrying, more complete utilization of quarry rock, avoidance of purchasing high calcium stone, lower fuel cost and improvement in the finished cement. Paul M. Tyler presented the general subject of milling methods as applied to nonmetal lies. He pointed out the importance of some of the more recent refinements in ore dressing, and urged the need of a wider appreciation of their possibilities. The gypsum industry of Canada was described by L. H. Cole. Crystal growth during the setting process was illustrated by moving pictures. The Coastal Plain and interior salt

Jan 1, 1935

Jan 1, 1944

Jan 1, 1944

By Gorr W. W., Wyche E. H, R. Smith

The combination of high strength and corrosion resistance of cold-worked 18 Cr, 8 Ni steel has been advantageously utilized for some time, particularly in aircraft and rail car structures. There are, however, certain limitations on the use of such materials because the high strengths can be obtained only by cold-working, limiting the available products to sheets, strip, wire and tubes. The authors sought to overcome these limitations by resorting to precipitation-hardening, which has been used so successfully in nonferrous metallurgy but only to a limited extent in iron-base alloys. Accomplishment of this objective not only overcame the limitations, but also effected certain improvements in mechanical and other properties. This paper is an account of the development by Carnegie-Illinois Steel Corporation of a precipitation-hardening 18-8 stainless steel (called Stainless W‡ and tentatively identified as type 322). A description is given of its composition and metallurgical characteristics, heat-treatment, physical and mechanical properties and corrosion resistance. Development of the New Steel For a considerable length of time the authors were unable to determine the mechanism of the precipitation-hardening process that had been noted by Ffield18,19 in 18-8 Ti or 18-8 Cb after cold-working and reheating to moderately elevated temperatures. All known variables were exhaustively studied, but with little success. However, results began to indicate that chemical composition was the most important variable, particularly the ratio of austenite-forming to ferrite-forming elements. The investigators then focused their attention upon the composition, and, in particular, upon the element titanium and its mode of alloying in the presence of other elements. A heat was obtained that could not be brought to the softness level of annealed 18-8. The response to cold-straining and aging* was very marked by previous standards, and, more important, cold-straining was found to be entirely unnecessary to produce the precipitation-hardening effect. The chemical composition of this heat was: C, 0.06 per cent; Mn, 0.54; P, 0.016; S, 0.016; Si, 0.58; Ni, 7.28; Cr, 17.60; Ti, 0.90; Al, 0.17. For some time the development work, particularly on composition, was carried

Jan 1, 1947

By Gorr W. W., R. Smith, Wyche E. H

The combination of high strength and corrosion resistance of cold-worked 18 Cr, 8 Ni steel has been advantageously utilized for some time, particularly in aircraft and rail car structures. There are, however, certain limitations on the use of such materials because the high strengths can be obtained only by cold-working, limiting the available products to sheets, strip, wire and tubes. The authors sought to overcome these limitations by resorting to precipitation-hardening, which has been used so successfully in nonferrous metallurgy but only to a limited extent in iron-base alloys. Accomplishment of this objective not only overcame the limitations, but also effected certain improvements in mechanical and other properties. This paper is an account of the development by Carnegie-Illinois Steel Corporation of a precipitation-hardening 18-8 stainless steel (called Stainless W‡ and tentatively identified as type 322). A description is given of its composition and metallurgical characteristics, heat-treatment, physical and mechanical properties and corrosion resistance. Development of the New Steel For a considerable length of time the authors were unable to determine the mechanism of the precipitation-hardening process that had been noted by Ffield18,19 in 18-8 Ti or 18-8 Cb after cold-working and reheating to moderately elevated temperatures. All known variables were exhaustively studied, but with little success. However, results began to indicate that chemical composition was the most important variable, particularly the ratio of austenite-forming to ferrite-forming elements. The investigators then focused their attention upon the composition, and, in particular, upon the element titanium and its mode of alloying in the presence of other elements. A heat was obtained that could not be brought to the softness level of annealed 18-8. The response to cold-straining and aging* was very marked by previous standards, and, more important, cold-straining was found to be entirely unnecessary to produce the precipitation-hardening effect. The chemical composition of this heat was: C, 0.06 per cent; Mn, 0.54; P, 0.016; S, 0.016; Si, 0.58; Ni, 7.28; Cr, 17.60; Ti, 0.90; Al, 0.17. For some time the development work, particularly on composition, was carried

Jan 1, 1947

By A. C. Lane

Relations de la profondeur de plissement avec la gravita-tion et la hauteur des montagnes dans les Alpes. Par A. Heim (Zurich) 50me Anniversaire, Livre Jubilaire Soc. Geol. De Belgique, Rome, Fascicule 1, 17 to 28. Measurements show a negative anomaly, less densities of .the material below sea level. The author expresses it in terms of the thickness of rocks of an arbitrary density, 2.4, which might be considered wanting. The accordant heights of the summits, the depths of the folds, the deficiency in .gravity, and denudation he finds to be connected. The Alps float on the lightness of the folds of "sal" of weight 2.6 to 2.75 plunged into the heavier "Sima" according to a for-mula: P = h (2.7/2.8-2.7) where - P is the depth of fold-ing below sea level; 2.7 is the weight of the material accu-mulated in folding; 2.8 is the weight of the material dis-placed by it; and h is the mean height of the mountainous regions. For instance, between the valley of Saar and the Val de Bagne in Valais the depth of the folds according to Ar-gand's profiles is between 30 and 40 kilometers. The loss of gravity has been estimated in this region as 1450 X 2.4 = 3480 in units of weight. Obviously errors in the densities would profoundly affect the estimates of the thickness of folding, but his depths of folds are obtained from sections, and from them he works back to the densities. Of course other densities might be placed in the formula. Zur Dichte bestimmung von Tonen. By J. Koenigsberger, Berg u. Hüttenmannisches Jahrbuch, 75, I. Discusses Dr. B. Wilser's investigations as to the best way of obtaining the weight of rocks per unit volume. The use of mercury for rocks affected by water as there recom-mended may easily give too large volumes unless 1 to 3 atm. pressure is used. Thick machine oil is recommended for large lumps of clay.

Jan 4, 1928

By G. R. St. Pierre, A. J. Wilhelem

In connection with the reduction of hematite or magnetite to metallic iron, it appeared desirable to study the rate of reduction of each oxide to the next lower oxide under conditions which excluded all other condensed phases. For this purpose, pellets of Fe,O,, Fe,O,, and oFeOo were prepared. A gas train for the preparation of Ar-Hz-H20 mixtures was employed to establish a continuous flow of a controlled atmosphere over a pellet suspended on a balance. In this manner the following individual reduction steps could be studied: For example, pellets of hematite were reduced solely to magnetite by adjusting the gas atmosphere such that it was oxidizing to wustite. In other words, the reaction was complete when the hematite pellet had been totally converted to magnetite. The pellets were prepared from Baker Chemical ferric oxide. The ferric oxide powder was moistened and handrolled. Air sintering at 950°C produced Fe,0, pellets with a density of 3.65 g per cm3. The pellets ranged in size from 0.6 to 1.2 cm diam. The magnetite and

Jan 1, 1962

By W. H. Hough, P. B. Leavenworth

Development during 1942 led to the discovery of 26 new fields in the Texas Gulf Coast, as compared with 27 during 1941. Of these, 19 are classed as oil fields, 4 distillate fields, and 3 gas fields. Production from the new fields amounted to 614,467 bbl. to October 1942. Producing Sections.—Discoveries in I942, compared with the previous two years, classified by producing formations, are shown in the following table: It is interesting to note the increase in Wilcox discoveries due to the extensive geophysical campaign that has been con. ducted since 1940. Drilling.—During the year 688 wells were drilled, of which 574 produced oil or gas and 114 were dry. This represents a considerable decline in activity over the previous year, when 1405 wells were drilled in the area, of which 1081 were producers and 324 failures. Jackson County continued to hold the lead, with 222 wells completed. Production.—-Despite curtailed drilling, production amounted to 118,009,451 bbl. for 1942, indicating a slight increase over the 113,726,893 bbl. produced during 1941. The statistics in Tables I and 2 include condensate and distillate as oil production, because many Gulf Coast fields produce oils with a wide variation of specific gravities, all of which are commingled in pipe lines. Table 3 shows by counties most of the activities referred to. The number of wells drilled includes only field wells; not wildcats. Outstanding Fields of 1942 The Texas Gulf Coast covered in this report has 270 more or less active oil and gas fields, including the new discoveries of 1942. Of these the most outstanding from the standpoint of production are listed in Table 4. Each of these fields produced one million barrels or more during 1942. Some of the fields where new extensions are occasionally referred to as separate fields, such as West Columbia and New West Columbia, or Thompson and South Thompson, are combined to give a more accurate outline. Two interesting facts may be noted from this list of some 26 oil fields: (I) that the Lolita field, Jackson County, is the only discovery since 1938 to produce more than one million barrels annually, although there have been 79 discoveries since Jan. I, 1940; (2) that 20 of these 26 fields produce from the Frio. New Fields ALief, Harris County.—Pure Oil Company's No. I Mike Albanese was drilled to 8637 ft. in Cook Mountain shale. After numerous tests the well was completed on Apr. 20, 1942, in a Yegua sand at 7919 to 7924 ft. for 54 bbl. of 52' gravity oil and 3,335,000 cu. ft. of gas through

Jan 1, 1943

By W. H. Hough, P. B. Leavenworth

Development during 1942 led to the discovery of 26 new fields in the Texas Gulf Coast, as compared with 27 during 1941. Of these, 19 are classed as oil fields, 4 distillate fields, and 3 gas fields. Production from the new fields amounted to 614,467 bbl. to October 1942. Producing Sections.—Discoveries in I942, compared with the previous two years, classified by producing formations, are shown in the following table: It is interesting to note the increase in Wilcox discoveries due to the extensive geophysical campaign that has been con. ducted since 1940. Drilling.—During the year 688 wells were drilled, of which 574 produced oil or gas and 114 were dry. This represents a considerable decline in activity over the previous year, when 1405 wells were drilled in the area, of which 1081 were producers and 324 failures. Jackson County continued to hold the lead, with 222 wells completed. Production.—-Despite curtailed drilling, production amounted to 118,009,451 bbl. for 1942, indicating a slight increase over the 113,726,893 bbl. produced during 1941. The statistics in Tables I and 2 include condensate and distillate as oil production, because many Gulf Coast fields produce oils with a wide variation of specific gravities, all of which are commingled in pipe lines. Table 3 shows by counties most of the activities referred to. The number of wells drilled includes only field wells; not wildcats. Outstanding Fields of 1942 The Texas Gulf Coast covered in this report has 270 more or less active oil and gas fields, including the new discoveries of 1942. Of these the most outstanding from the standpoint of production are listed in Table 4. Each of these fields produced one million barrels or more during 1942. Some of the fields where new extensions are occasionally referred to as separate fields, such as West Columbia and New West Columbia, or Thompson and South Thompson, are combined to give a more accurate outline. Two interesting facts may be noted from this list of some 26 oil fields: (I) that the Lolita field, Jackson County, is the only discovery since 1938 to produce more than one million barrels annually, although there have been 79 discoveries since Jan. I, 1940; (2) that 20 of these 26 fields produce from the Frio. New Fields ALief, Harris County.—Pure Oil Company's No. I Mike Albanese was drilled to 8637 ft. in Cook Mountain shale. After numerous tests the well was completed on Apr. 20, 1942, in a Yegua sand at 7919 to 7924 ft. for 54 bbl. of 52' gravity oil and 3,335,000 cu. ft. of gas through

Jan 1, 1943

By R. W. Stahl

Employees and dollars are necessary to all enterprises and any force, such as fire, which destroys either, can bring very serious consequences, including business failure. Since everyone acknowledges the necessity of conserving human life, we will devote most of our paper to the economic factors involved. A coal-mine fire is considerably more difficult to combat than a fire in a surface building because of the combustible surroundings in the mine, the explosive gases emitted from the coal, the suspension of explosive dust when mine timbers burn and the unsupported roof falls, the limited space in which approach to the fire can be made, and the limited avenues of escape. A survey of coal-mine-fire protection indicated that a rather low value was being placed on property and equipment. This prompted comparison with other industries. The comments made in this comparison are not intended as an indictment of the coal industry, since we do have mines that are well protected against fire, but the comments on conditions at the mines visited are factual and may help others to improve similar conditions. SURVEY PROCEDURES Plants of the steel, aluminum, rubber, chemical, and petroleum industries were surveyed, and all facets of the fire-protection scheme were covered. The industrial plant invariably had four times as much water readily available for instant use than the mine. In many mines where water is available, no equipment for applying it is provided, such as hose, nozzles, and adapters, so that time is lost in collecting this equipment. (See Table I.) EXTINGUISHERS Many more and generally larger portable extinpishers are available at the plant as compared to the mine. The extinguishers are generally placed nearer to sources of danger. In addition, respiratory protective equipment is always available at strategic points in plants but only in a few mines. (See Figs. 1 and Table 11) INSPECTING AND TESTING EQUIPMENT Plant water facilities are checked weekly and flushed at 6-month intervals, and hose is pressure-tested at least yearly; some mines check water yearly, but hose is not tested unless used. Fire extinguishers are inspected weekly in plants and completely overhauled yearly; one mine had monthly checks and overhauls only after use. FIRE BRIGADES AND TRAINING Every plant had designated fire-fighters and some complete full-time brigades; at one mine a chief mechanic was designated as being in charge of fires, and other depended entirely upon officials who might not be familiar with the equipment. COST OF FIRES AND PERCENTAGE OF CAPITAL INVESTMENT IN FIRE PROTECTION The direct cost of recent mine fires ranged from $128,000 to $240,000; indirect costs, such as lost tonnage, idled equipment, lost orders, and the like might run the cost to over $500,000. (See Figs. 2 and 3).

Jan 1, 1961