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By Clinton M. Young

(Pittsburg Meeting, March, 1910.) I. INTRODUCTION. THE experiments herein. described were carried on in 1908-9 . by the State Geological Survey of Kansas. Some months before taking up work on black powder the Survey had resumed work on an interrupted investigation of explosions in coal-mines, a subject which is engaging the attention. of numerous investigators. An unusual number of serious disasters has directed to. the subject a study which discloses the disquieting fact that, in the. United States, the ratio of lives lost per ton of coal mined has been on the increase. Methods of coal-mining have changed to some extent with the great increase of output, attained in, comparatively recent years. These changes involve the working of very extensive mines, with increased difficulty of ventilation, increased accumulation of coal-dust, and. a very great increase in the amount of explosive used.. . This last point assumes truly startling proportions when it is carefully observed. In the fields of the Middle. West it is not now uncommon for a miner to use six ,kegs (150 lb.) of black powder in a "pay" of two weeks, while within the memory. of men still active, one keg (25 .lb.) would last two men for a " pay." So. great has . the use of explosives become in some fields that the skilled coal-miner is hard to find, and the coal is not mined, but blasted. A preliminary study of the subject. of explosions in coal-mines has. led to the belief . that the use of, large -quantities of explosives, in some cases by slightly-trained men, had not been * Associate Professor- of Mining Engineering, University of Kansas, Lawrence, Ran.

Aug 1, 1910

By Paul L. Russell

THIS is a progress report of an experiment being undertaken in cooperation with the Bethlehem Steel Corp., the Crucible Steel Co., and the Rock Bit Sales and Service Co., involving heat treatment of the shank ends of drill steel. This experiment is being conducted by the U. S. Bureau of Mines in its experimental mine, Mining Research Branch, Bluemont, Va. The purpose of the experiment is to determine the effect of an increase in the time the steel soaks in the furnace during the hardening heat. It has been thought that increasing this time produces a soft zone below the lugs resulting in a metallurgical notch that causes early failure. Each of the steel companies furnished enough 11/4 - in. straight carbon, hollow, round steel to make up 10 sets of drill steel, in each instance the steel bars were from the same heat. These sets of drill steel, consisting of 2-ft, 4-ft, 6-ft, and 8-ft lengths were fabricated by the Rock Bit Sales and Service Co. Special attention was given to the forging of the steel to produce the best rods possible. The heat treatment of all thread ends was identical and followed the best practice. The heat treatment of the shank ends of five sets of steel from each company produced a soft zone 2 to 4 in. in front of the lugs. It was decided that possibly the best way to obtain this effect was not to overlap the hardening heat but to let the steel soak for an additional 30 min before quenching. Therefore the only variable in the test steels is the length of time the shank ends were in the furnace. The remaining drill steel shanks were treated as follows: Heat treatment in pyrometer-controlled furnace at 1550°F. Quenching oil at 105°F to 125°F temperature. Areas for heat treatment were; shanks, 11 in.; threads, 9 in. Time at heat, standard practice, 20 min for 11/4-in. steel. Actual drilling tests were made in greenstone, (a metamorphosed basaltic rock), and in epidosite. Greenstone has a specific gravity of 2.96 and a compressive strength of 44,200 psi. Epidosite has a specific gravity of 3.26 and a compressive strength of 63,100 psi. All drilling tests were made using a 31/2-in. column-mounted, automatic feed drifter, with a controlled air pressure of 90 psi at the throttle. Tungsten-carbide bits of 2 in. diameter were used for all drilling. Contrary to expectations the drill steels that were allowed to soak for the additional 30 min before quenching performed better than the steels that were heat treated according to standard practice. This performance, as shown in Table I, was especially noticeable in the drilling of epidosite. The "longheat" drill steels furnished by Company "A" drilled 154 pct more minutes than the "standard-heat" steel. Expressed in feet, the "long-heat" steel drilled 114.60 ft more before failure than the "standard-heat" steel. The "long-heat" steel furnished by Company "B" drilled 37 pet more minutes or 60.39 ft more before failure than the "standard-heat" drill steel. The effect of the long heat treatment was not as evident when the steels were drilling in greenstone (Table II). In greenstone, the increase in minutes drilled by the "long-heat" steel over the "standard-heat" steel was 47 pet and 1 pet, respectively, for Companies "A" and "B."

Jan 1, 1952

The following advertisements show the contemporary view of the value of coal on a tract, usually as compared with farming advantages of several kinds. Fayette Gazette and Union Advertiser, February 10, 1798: "For Sale in Washington twp., Fayette Co., 211 acres of land whereon is a good new grist merchant mill, a good stone dam, and a house for the miller, about two acres of bottom, cleared and fenced, an excellent coal bank and saw-mill seat unimproved." Pittsburgh Gazette, March 19 and 26, 1802: Ads. offering for sale two properties, one of 38 acres, "together with a Coal Pitt and Lime Quarry, lying on the Monongahela side of Grant's Hill, and within one mile and a half of Pittsburgh," and the other two tracts of 700 acres on "Racoon creek, contiguous to which is a valuable limestone quarry, and a quarry of building stone, also plenty of stone coal." Pittsburgh Gazette, Oct. 8, 1802: A farm between Pittsburgh and Greensburg "with house, barn and a Smith shop-also, a fine sugar camp, and a Coal Bank within sight of the house," was offered for sale. The Farmers Register, Greensburg, Pa., March 13, 1802: An advertisement of a "plantation, six miles from Greensburg, there are two coal banks on it, one at each end of the place." The Commonwealth, Pittsburgh, Aug. 4,1805: A number of lots were laid off on Saw Mill Run, nearly opposite the first opening made on the Pittsburgh seam. They were from two to twenty acres each "and a great quantity of Limestone and stone coal." Pittsburgh Gazette, Aug. 9, Sept. 6, Sept. 27, Oct. 4, 1811; The Commonwealth, Aug. 19, 1811: Five tracts were advertised that contained coal. One had "fine springs and an inexhaustible mine of coal;" one, "excellent sugar camps, coal banks and limestone and a good mill seat;" one, "good sugar camps, an excellent coal bank and an elegant seat for a distillery;" another, a tract of 45,000 acres in Allegheny and Butler Counties affording "stone coal and iron ore, and seats for water works;" and the last a tract on Beck's Run, four miles from Pittsburgh "and a coal pit opened about one fourth of a mile from the river." The Mercury, Pittsburgh, April 8, Jan. 14, Feb. 11, 1813; Pittsburgh Gazette, April 16, Dec. 3, 1813: These tracts were advertised during the year in the vicinity of the city. One had "a good sugar camp, woodland and plenty of coal;" another, "a sugar camp and a coal bank on the premises;" while the others were "well timbered or well watered and had excellent stone coal." The Mercury, Pittsburgh, Feb. 2, 1814: A farm was offered for sale on the headwaters of Robinson's Run, in Washington County, four miles from Burgettstown, containing 60 acres, "a young bearing orchard,... a coal bank and a good sugar camp." Genius of Liberty and Fayette Advertiser, Uniontown, Pa., March 2, 1814, carried an advertisement of a sale of lots in the new town of Perriopolis; "the quantity and quality of the clay, sand and salt licks, near the premises, together with the timber and abundance of .stone coals The town of Perriopolis was situated upon a . farm at one time belonging to Washington.

Jan 1, 1942

By John Griffen

This paper records over twenty years' experience with the use of the Rheolaveur system in the United States, showing its ability to meet changing conditions caused by the dirtier mine output of present-day mechanical mining methods. Data are given on size ranges handled, number and capacity of units installed, maintenance experience, and operating results on two-product and three-product separations. IT is not the purpose of this paper to discuss the principles employed in the Rheolaveur system of fine-coal cleaning as these have been fully covered in the technical literature of the Institute."2 Rather, our purpose will be to record the highlights of over 20 years' experience in the United States with Rheolaveur fine-coal launders, which will indicate their capabilities and costs of cleaning and their adaptability to meet the changing conditions caused by present-day mechanical mining methods. Rheolaveur fine-coal launders are used in the United States to treat a wide variety of size ranges of fine coal, the coarsest being 1/2 in. to 0 and the finest about 1/8 in. to 0. In Europe feeds as coarse as 5/8 in. and as small as 1/2 mm (28-mesh) to 0 are being cleaned. The size ranges usually handled in this country are 3/8 to 1/4-in. round to 0. Thirty five units with a combined hourly feed capacity of 3200 tph have been installed in the United States. Individual units are cleaning as little as 25 tph, while others are cleaning as much as 200 tph. Rheolaveur fine-coal launders offer cleaning units of high capacity and are outstanding in requiring a minimum of building space per ton of input. Experience has shown that maintenance costs are low. Several installations were made in the Pittsburgh district from 1928 to 1930, and since that time operation has been largely two shifts per day. Minor repairs to liner plates and Rheo boxes have been required during the intervening years, but no major replacement of launders was required until 1947 and 1948. At one of these plants, launders operated for 17 years before they were replaced and during that period over 26,000,000 tons of —5/16-in. coal were cleaned. The effect of the much dirtier raw coal produced by mechanical loading of the Pittsburgh seam is shown by the following tests. The data in table I summarize the performance of a Rheo fine-coal unit when cleaning hand-loaded raw coal. The —4-in. raw coal fed to the cleaning plant analyzed only 8.16 pct ash and 1.31 pct sulphur and contained 4.6 pct sink, 1.55 sp gr. Two years later, in 1945, mechanically-loaded coal from the same mine was cleaned in the same plant. The feed, —4 in., then analyzed 20.10 pct ash and 1.53 pct sulphur and contained 20.2 pct sink, 1.55 sp gr. The performance of the Rheo fine-coal unit when cleaning this coal is given in table 11. It will be noted that the +48-mesh coal is cleaned almost as thoroughly as in table I. The large amount of high-ash slimes produced from the dirtier feed are responsible for the higher ash of —--48-mesh washed coal in table 11. In this plant the Rheo fine-coal unit did not get the full load of refuse resulting from mechanical

Jan 1, 1951

By John Griffen

This paper records over twenty years' experience with the use of the Rheolaveur system in the United States, showing its ability to meet changing conditions caused by the dirtier mine output of present-day mechanical mining methods. Data are given on size ranges handled, number and capacity of units installed, maintenance experience, and operating results on two-product and three-product separations. IT is not the purpose of this paper to discuss the principles employed in the Rheolaveur system of fine-coal cleaning as these have been fully covered in the technical literature of the Institute."2 Rather, our purpose will be to record the highlights of over 20 years' experience in the United States with Rheolaveur fine-coal launders, which will indicate their capabilities and costs of cleaning and their adaptability to meet the changing conditions caused by present-day mechanical mining methods. Rheolaveur fine-coal launders are used in the United States to treat a wide variety of size ranges of fine coal, the coarsest being 1/2 in. to 0 and the finest about 1/8 in. to 0. In Europe feeds as coarse as 5/8 in. and as small as 1/2 mm (28-mesh) to 0 are being cleaned. The size ranges usually handled in this country are 3/8 to 1/4-in. round to 0. Thirty five units with a combined hourly feed capacity of 3200 tph have been installed in the United States. Individual units are cleaning as little as 25 tph, while others are cleaning as much as 200 tph. Rheolaveur fine-coal launders offer cleaning units of high capacity and are outstanding in requiring a minimum of building space per ton of input. Experience has shown that maintenance costs are low. Several installations were made in the Pittsburgh district from 1928 to 1930, and since that time operation has been largely two shifts per day. Minor repairs to liner plates and Rheo boxes have been required during the intervening years, but no major replacement of launders was required until 1947 and 1948. At one of these plants, launders operated for 17 years before they were replaced and during that period over 26,000,000 tons of —5/16-in. coal were cleaned. The effect of the much dirtier raw coal produced by mechanical loading of the Pittsburgh seam is shown by the following tests. The data in table I summarize the performance of a Rheo fine-coal unit when cleaning hand-loaded raw coal. The —4-in. raw coal fed to the cleaning plant analyzed only 8.16 pct ash and 1.31 pct sulphur and contained 4.6 pct sink, 1.55 sp gr. Two years later, in 1945, mechanically-loaded coal from the same mine was cleaned in the same plant. The feed, —4 in., then analyzed 20.10 pct ash and 1.53 pct sulphur and contained 20.2 pct sink, 1.55 sp gr. The performance of the Rheo fine-coal unit when cleaning this coal is given in table 11. It will be noted that the +48-mesh coal is cleaned almost as thoroughly as in table I. The large amount of high-ash slimes produced from the dirtier feed are responsible for the higher ash of —--48-mesh washed coal in table 11. In this plant the Rheo fine-coal unit did not get the full load of refuse resulting from mechanical

Jan 1, 1951

By J. M. GLEDHILL

IT would doubtless have been felt by many but a few years back that there was little left to be said on the subject of crucible tool-steel, and that something akin to finality had been arrived at in its manufacture and general treatment. Probably such feeling was justifiable when it is remembered that the making of steel in crucibles is by far the oldest method known, dating back from time immemorial, it being indeed impossible to accurately trace its origin and earliest development; but it seems certain that carbon-steel was made and used thousands of years ago for cutting-tools. Proof of this may be seen by the marvelous carvings and workings on the intensely hard stone-work of the ancients, for it would be difficult to conceive by what means, other than with steel tools, such work could have been executed; and it is wonderful to contemplate that steel cutting-tools should have been used so long ago, whilst the principle of manufacturing them-that is, by fusion of iron and charcoal in crucibles-was then in a measure on the sane lines as we work on at the present day. Archaeologists have discovered that the Chinese made steel in crucibles long before the Christian era. " Wootz " steel fabricated in India centuries ago was crucible steel, as was also the celebrated Damascus steel, produced at the forges of Toledo, and, curiously, this latter steel furnishes' yet another proof that "There is nothing new under the Sun," for it is recorded that Damascus steel contained certain percentages of tungsten, nickel, manganese, etc., some of the very elements, in fact, contained in the present modern high-speed steel, so that a latent high-speed steel may be said to have existed

Mar 1, 1905

By A. O. Drysdale

In Canada, the market for cement is not a national one but rather a collection of local or regional markets. Excess capacity on a national basis does not necessarily preclude a shortage on a regional basis. with portland cement selling for less than a cent a pound, the low price-to-weight factor makes transportation to the market a major cost item and thus a small plant can be justified to serve a limited regional market. The Brookfield plant of the Canada Cement Co. is designed to supply the Province of Nova Scotia, a regional market that shows promise of growing to a point where it will support a one-kiln plant. The market is presently being served by boat shipments from the Canada Cement Co. plant at Montreal East, Quebec, and from the North Star Cement Ltd. plant at Corner Brook, Newfoundland, and by rail and road shipments from the Canada Cement Co. plant at Havelock, N. B.

Jan 4, 1965

By I. C. Edwards, W. J. Dengler, D. F. Lillie

By 1959 the milling plant of Bicr oft Uranium Mines Ltd. had been in operation for two years. During this time many changes, both physical and chemical, had been made in an effort to improve plant efficiency. Investigational work had been facilitated greatly by the fact that the Bicroft mill consists to a large extent of two parallel circuits; however, the number of interrelated variables is great, and it is difficult to measure, let alone control, all of them simultaneously. The Bicroft mill staff feels that much progress has been made, but there is much yet to be done and many questions still to be answered. The Addendum outlines noteworthy developments to the fall of 1960. The property of Bicroft Uranium Mines is located in Cardiff Township in the Highlands of Haliburton County, southeastern Ontario, some 140 miles northeast of the city of Toronto and 70 miles due north of Lake Ontario. The ore-bearing dikes are classed as mafic. nonsegregated, syenite and granite pegmatite. Microline, microline perthite, quartz, sodic plagioclase, and pyroxene or biotite are the main constituents with uraninite, uranothorite, fluorite, titanite, cryolite, calcite, pyrite, pyrrhotite, and molybdenite as important accessories. The mill was designed for a nominal capacity of 1000 tpd with all sections except grinding, leaching, and clarification capable of 1500 tons. Feed was entered to one mill unit on Oct. 29, 1956, and to the second parallel line on November 13. The total feed rate was at 1000 tpd on November 15. The first precipitate was produced on November 12. By August 1958 the average entry had been increased to 1410 tpd without the installation of any additional major equipment. The overall recovery has been greater than 93.0 pct on several months, but a recovery of 92.5 pct appears to be most economical. Operating time for eight months in 1958 has been 97.1 pct although all grinding mills were relined during this period. A generalized flowsheet is shown in Fig. 1 and the plant layout in Fig. 2. The ore is crushed in three stages to -3/8-in. and then is wet ground in two stages to approximately 50 pct -200 mesh. The pulp is thickened to 68 pct solids and agitated by air for 33 hr at a pH of 1.9 as maintained by the addition of 93 pct sulfuric acid. Separation of the uranium-bearing pregnant liquor from the residue is accomplished by five-stage countercurrent decantation (CCD), following which the liquor is clarified for removal of fine slimes. The clarified liquor is treated in the ion exchange equipment in which both the upgrading of the solution and the removal of some impurities is accomplished. Addition of magnesia to the high-grade eluate from ion exchange precipitates the uranium as sodium-magnesium diuranate. After being filtered and dried this precipitate is packaged in drums for shipment. The residue from CCD and the barren solution from ion exchange are neutralized by the addition of lime and pumped to the tailings disposal area. CRUSHING All crushing is done on surface in a conventional three-stage unit consisting of a 36x48-in. Birdsboro Buchanan jaw crusher, a 4 1/4-ft standard Symons cone crusher, and a 4-ft Symons shorthead. Both the two primary and the two secondary screens are 4X 8-ft Symons rod decks. Moisture content of the feed ranges from 3 to 4 pct. In the initial installation the primary screens were equipped with 5/16-in. rods at 1 1/4-in. spacing and the secondaries with 5/16-in. rods at 1/2-in. spacing. With this arrangement the average crushing rate was better than 180 tph. To reduce the work required of the grinding circuit as tonnage was increased, several changes were made in the crushing circuit. By September 1957, both secondary screens had been reduced to 3/8-in. spacing, and rod size had been reduced to 3/16-in. to provide increased open area. Average throughput was reduced to 160 tph. Later, 50 pct of one primary screen was decreased to 1/2-in. opening to better balance the load between the two cone crushers. In May 1958,

Jan 1, 1961

By Donald F. Hammer, Donald W. Peterson

The Magma mine at Superior, Arizona, has produced over 13 million tons of ore yielding 1.5 billion pounds of copper. It is a mesathermal deposit, and, although the bulk of the ore has come from the Magma vein, most of the recent production has come from replacement deposits in limestone. The mine lies in a Precambrian and Paleozoic sequence of rocks that includes schist, diabase, quartzite, shale, and limestone; nearby, these rocks are intruded by igneous bodies of Mesozoic age that were probably the source of the ore-bearing fluids. Locally, these rocks are overlain by Cenozoic volcanic rocks and conglomerate. Layered rocks at the mine dip eastward about 30°. The area is extensively faulted, and surface faults are grouped into an earlier east-trending set and a later northtrending set. An additional set of diagonal faults that trends northwest and northeast is recognized underground. The east-trending Magma vein-fault, with its splits and branches, is the principal mineralized structure of the district. The bulk of the ore occurs in large ore shoots that plunge steeply westward and are sporadically connected by irregular ore shoots dipping gently eastward. The main ore controls apparently are selective zones of permeability related to the transverse faults. A bed of crystalline limestone near the base of the Martin Limestone (Devonian) is the host for the replacement ore bodies-discontinuous tabular pods dipping eastward parallel to the bedding. Selective permeability is again the apparent ore control, caused both by local hydrothermal solution of limestone and by deformation along faults. The principal copper minerals in the vein are chalcopyrite, bornite, enargite, tennantite, chalcocite, and digenite; these minerals vary in abundance according to a distinct zoning pattern. The upper part of the mine yielded considerable zinc as sphalerite, and the oxidized zone was rich in silver. The chief gangue minerals are pyrite, quartz, and hematite. In the limestone replacement bodies, chalcopyrite and bornite are the chief ore minerals.

Jan 1, 1968

By AIME AIME

T HE 121st meeting of the Institute held in New York City, February 16 to 19, 1920, was a great success despite vicissitudes of weather of unusual severity. On account of tremendous snowstorms, only two members of the Canadian contingent arrived, and several of our members from the west arrived thirty hours late. Two weeks prior to the meeting, the heaviest snowstorm in 34 years wrecked the surface transportation in New York; and it was only by special dispensation that arrangements were effected, with the New York Street Cleaning Department to clear away 39th street in front of this building so that vehicles could reach the curb. The total registration of members and guests was 1138.

Jan 1, 1920

By B. M. Larsen, T. E. Brower

A perspective is presented of the steel plant sulphur distribution and elimination problem from coal to liquid steel ready for teeming, giving distributions of sulphur over a range of coke sulphur content, and some methods of sulphur control, in the blast furnace, external desulphuriza-tion between blast furnace and open hearth, distribution between fuel, slag, and metal, and methods and limitations of control of sulphur in the open hearth furnace. AS a part of the 1951 AIME symposium on sulphur in steelmaking, it was thought that a discussion of the distribution of sulphur throughout the whole series of operations, from coal and ore to finished steel ingots, might have some value in giving a perspective on the whole problem. The following discussion is an attempt to present such an overall picture. The order is that of the actual plant operations, beginning with a very brief consideration of the coking process. Sulphur in Coal and Coke Since by far the largest source of sulphur entering the steelmaking cycle is in the coal used to make coke for the blast furnace, it would seem reasonable to eliminate some of it, either from the coal, or the coke, or during the coking process. This has appeared impracticable up to the present, at least, for two main reasons: the low activity of the organic sulphur in either coal or coke, and because of price limitations involved in treating a low cost material such as coke. A variable portion, usually M or less, of the sulphur is present in coal in the form of pyrites or similar compounds, and a large part of this sulphur may be removed in the coal washery. Most of the sulphur, however, is normally present as "organic" sulphur, intimately associated with the coal structure. Its distribution prevents any separation by mechanical means. Its low activity makes improbable ' any rapid chemical removal, although hydrogen will remove sulphur from both coal and coke. Thus, prolonged recirculation of coke oven gas in the coking process would tend to leave a smaller percentage of the total sulphur in the coke residue. Table I shows a typical distribution of sulphur from coal into products in the coking process. As the sulphur in the coal increases, the sulphur in the coke tends to increase in about the same proportion. Sulphur in the Blast Furnace The best picture of the situation in the blast furnace is provided by a sulphur balance of raw materials entering, and of products leaving, the furnace. The difficulties in accurate weighing and sampling of the variable solid materials entering this process, and the number of hours required for the raw materials to descend through the furnace under variable operating conditions, make it difficult to obtain an accurate balance. However, balances made over periods of weeks or months tend to average out some of these uncertainties. Table I1 presents three typical sulphur balances similar to a number that the writers have calculated. In most of these the slag volume calculated from the sulphur balance is, in some instances more, and in other instances less, than the value corresponding to the best input and output balances of the other slag constituents (lime, silica, alumina, etc.). Probably the greatest source of error in these calculations is the sulphur content of the slag. Despite some possible inaccuracies the balances of Table II show rather definitely the following points: 1—That 87 to 95 pct of the total sulphur input is in the coke and 95 to 97 pct of the total sulphur output is in the slag. Also, that if any sulphur leaves the furnace with the gas it is relatively small, amounting to a possible 1 pct or less. 2—At the lower sulphur coke level of 0.86 pct the total amount of sulphur charged is 15 Ib of sulphur per ton iron increasing to 26 lb per ton at the higher sulphur, intimately associated with the coal struc-rare burdens containing sulphur-rich ores will the total sulphur burden fail to be nearly proportional to the content in the coke used. 3—The 7 to 9 pct of the total sulphur input from the limestone of furnaces B and C is due to the relatively high sulphur content of the stone, 0.226 and 0.265 pct, respectively. In the case of furnace A, the sulphur content of the limestone was only 0.06 pct which resulted in only 3 pct of the total sulphur input coming from this source. It is rather interesting to compare the sulphur balances of a typical ferromanganese furnace with

Jan 1, 1952

By H. G. HYMER

B ECAUSE of its remote geographical position and inaccessibility, little is generally known of the mining and prospecting in Northern Rhodesia. In this rather new and promising region, the development of mines presents many difficulties. Although many mineral discoveries have been made, progress in .prospecting the huge mining concessions has been handicapped by the lack of roads, communication, transportation, native population and incomplete knowledge of geology.

Jan 1, 1929

By AIME AIME

A THOROUGHLY satisfactory crowd turned out at the fall meeting of the Industrial Minerals Division and took an active part in the entire program. On Thursday afternoon, Sept. 24, a limestone plant was inspected, technical sessions occupying the attention of the visitors all day Friday and Saturday morning. Headquarters were at the Nittany Lion Inn, an attractive hostel on the Penn State campus, at State College, right in the center of Pennsylvania. We are still in the dark, despite inquiries, as to just what breed of lions Nittany lions are. As nearly as we could find out, Nittany is not a Biblical name, as it sounded to us, but a corruption of the name of an Indian princess, or maiden, or maybe just girl that haunted those parts in bygone times and after whom a near-by mountain was named. Penn State athletes are "lions" and there you are. The meeting was supposed to be a joint one with the American Ceramic Society's Materials and Equipment Division; but it was quite evident that the Institute had a much better publicity agent than the Society, which bothered Ross. Purdy, the aggressive secretary of the ceramic people, no end. However, Secretary Purdy saw to it that everyone present fully understood that the Ceramic Society was present, so that that contingent all but stole the show, its representatives presiding at every meeting. The Pittsburgh Section of the American Ceramic Society was also supposed to be holding its fall meeting there at the same time, but made no trouble at all for anybody, as one of the speakers remarked.

Jan 1, 1936

By R. E. Maringer, B. A. Wilcox, A. H. Clauer, J. H. Sovik

Internal friction measurements from 25° to 1100°C have been made on specimens machined from TD nickel bar. The use of miniature torsional pendulum specimens alloived damping measurements to be made on specimens whose axes were parallel to the original bar axis, at 45 deg to the bar axis, and at 90 deg to the bar axis. There was a marked difference in damping with varying specimen orientation, and this was related to the pronounced micro structural anisotropy of this material. Varying the microstructure by cold working plus re crystallization annealing also greatly affected the damping behavior. Recrystallization essentially removed the broad peak found at 400° to 650°C in as-received TD nickel, and in addition greatly lowered the background damping. DlSPERSION hardened metals such as SAP-type alloys (Al + AI2O3) and TD nickel (Ni + 2 pet ThO2) have been developed primarily to improve high temperature strength properties. There have been numerous damping studies on SAP-type alloys,1"9 and one of these6 showed that the damping capacity was greater than that of 99.5 pet pure Al from 25° to 600°C. Several preliminary observations on TD nickel10 and an experimental Ni-ThO2 alloy11 indicated that here, too, the damping capacity was quite high. A high damping capacity in TD nickel, combined with its relatively good high temperature creep strength, could provide an additional benefit for some high temperature structural applications. This work was undertaken to study the internal friction behavior of TD nickel bar over the temperature range 25° to 1100°C. In Ni-ThO2 and Ni-Cr-ThOz alloys, other properties such as steady-state creep rate,12 creep rupture life,12'13 modulus of elasticity,14 and ultimate tensile strength,14 are sensitive to orientation with respect to the primary working direction. Thus, in order to examine anisotropy effects in damping, studies were made on specimens machined with their axes parallel, at 45 deg, and transverse to the original bar axis. MATERIAL DESCRIPTION AND EXPERIMENTAL PROCEDURES The material used in this investigation was from the same £ in. diam TD nickel bar that has been studied previously.13'15 The structure typical of the as-received TD nickel is shown in Fig. 1, and additional details of the structure can be found in Refs. 13 and 15. Elongated grains are parallel to the bar axis and are about 10 to 15 u long and about 1 u in diam. This structure is very stable, since no recrys-tallization or grain growth occurred after annealing for 3 hr at 1300°C.13 The total ThO2 content was 2.3 vol pct and the particles ranged in diameter from 100 to 1000. The average particle diameter was 370Å and the mean planar center-to-center particle spacing was 2340Å. To examine the influence of grain and subgrain structure on damping, a section of TD nickel bar was swaged and drawn at room temperature from 1/2 in. diam bar to 0.040 in. diam wire (99.3 pct re-duction in area). The structure in Fig. 2 resulted after the wire was annealed for 3 hr at 1250°C. The recrystallized grains were much larger than the grains in as-received bar, but still showed considerable elongation in the direction of working. A high

Jan 1, 1970

By W. H. Smith

IN the course of an investigation on chromium containing minor amounts of alloying elements, the information herein has been obtained on the crys-tallographic orientations resulting from arc melting, rolling, and annealing. The chromium used in this investigation was electrolytic flake obtained from the Electro Metallurgical Co. This material was heated for 20 hr at 1600°C in hydrogen with a dew point of about — 100°C. The oxygen and nitrogen content of the chromium after this treatment was 0.0003 pct 0 and 0.005 pct N. Five pounds of this chromium were arc melted in a water-cooled copper crucible. After arc melting, the oxygen and nitrogen contents were 0.002 and 0.025 pet, respectively. A section of this ingot is shown in Fig. 1. By means of a back-reflection Laue technique, the crystal habit of the cast ingot was determined. As expected, it was found that the [loo] was approximately the axis of the columnar grains. In this respect, chromium behaves like other body-centered-cubic metals in that a cubic axis is normal to the cold surface of the mold. A slab cut from this ingot was rolled at 600°C as follows: four 30 pct reductions were made with intermediate anneals at 1200°C for 15 min. Rolling was done with the [loo] of the columnar grains in the rolling direction. Following the final anneal, an 80 pct reduction was taken at 600 °C. The final sheet thickness was ten mils. By polishing and etching, the thickness was reduced to four mils and the grain orientation determined by the transmission Laue method using molybdenum radiation with a zirconium filter. Fig. 2 is the (110) pole figure for this material with the ideal (100) [011] and (111) [112] orientations indicated. The orientation is typical of most cold rolled body-centered-cubic metals having the [llO] of the grains approximately in the rolling direction and the (100) planes approximately in the plane of the rolled sheet. There is also evidence of some 10) [1 orientation. The grain orientation of sheet rolled 40 and 80 pct in the same direction as before at 600°C followed by recrystallization at 12000 C for 15 min was determined by a back-reflection Laue technique. A random texture was found in both cases. This 1200°C 15 min anneal was found to give complete recrystallization and some grain growth.

Jan 1, 1956

ALABAMA. Anniston.-Noble, A. E., 20th St. and Wilmer Ave. Auburn.-Brown, R. L., Box 0. Belle Ellen.-Hutcheson, W. C. Bessemer.-Abbott, C. E., T. C., I. & R.R. Co Dobbs, G. G., Box 97. Ferguson, V., U. S. C. I. Pipe & Fdy. Co. Williams, E. P., Tenn. C., 1. & R. R. Co. Birmingham.-Aldrich, T. H. Aldrich, T. H., Jr., 406 Woodward Bldg. Allen, A. W., 1616 S. 14th Ave. Bowron, J., 1401 S, 20th St. Burbidge, T. A., Brown-Marx Bldg. Coxe, E. H. Tenn. C., I. & R. R. Co. Crawford, C. G., Tenn. C., I. & R. R. Co. Crockard, F. H., Brown-Marx Bldg. Ellis, E. E.,1515 Brown-Marx Bldg. Fairbairn C. T., Woodward Bldg. Fies, M. H., 2316 Highland Ave. Geismer, H. S., Keiser-Geismer Engrg. Co.

Jan 1, 1917

By AIME AIME

Change of Meeting from Birmingham to Chattanooga. In consequence of the disturbed conditions attending a long¬continued labor strike in Alabama, the meeting of the Institute was changed from Birmingham, Ala., to Chattanooga, Tenn., where it will. begin on Thursday evening, Oct. 1, 1908. Information. of this change bad been sent to the newspapers through the Associated Press, and by circular to all members, when news was received of the sudden and unexpected termination of the strike referred to. It was, unfortunately, too late to change once more the arrangements for the meeting. But it is hoped that the cordial invitation of the citizens of ,Birmingham may be renewed and accepted at a future time, not too remote. Office Facilities for Visiting Members. A separate room in the suite occupied by the American Institute of Mining Engineers on the ninth floor of the United Engineering Society Building, has been equipped with furniture and telephone extension for the temporary use of members of the Institute or of sister societies, or visitors suitably accredited. Members of the Institute visiting New York for a short time, who need office facilities during their stay, or members residing in the city. who need temporary office accommodation, can arrange to have set apart for their exclusive use a room, equipped with office furniture, telephone, etc.,. in the suite of the Institute. It is not the intention to give possession of the room to any individual for an indefinite time, but to offer to members of the Institute an opportunity to acquire a well-located, well-equipped business headquarters to carry on transactions which

Jan 9, 1908

By D. Cox, M. J. Duggin, L. Zwell

The carbides of approximate composition and Mn have been studied using X-ray diffraction techniques. Those carbides of the type (Fe,Aln)zC ave isostructural with cementite. The cell pararmeters a and c have minimum values at approximately 10 at. pd substitution of manganese for iron; no satisfactory explanation has yet been found for this phenomenon. The carbide fFeMn4)C has a monoclinic unit cell whose dimensions are close to those of ,11,15Cz A neu-troip-dij~ractiot~ study of (F'eAlrz4)C~ reveals that, like MnsCZ, it is isostructural with Pd5Bz. The iron and manganese atoms occupy the palladium atom sites, while the carbon atoms were found to have the same atomic coordinates as the hovon atoms. A neutrorr-diffraction study of indicates that the carbon-atom positions are very close to those occupied in (Fez.,ll/lr~,.3)C. In both carbides studied, tlre iron and manganese atomzs were found to be essentially randomly distributed, although, in the case of (Fe,.811fn1.2)C, it is possible that there may be a slight preference of manganese atoms for- the general (d) positions and a corresponding slight preference of iron atoms for the special (c) positions. It has been found that a complete range of solid solution exists between Fe3C and Mn3C at 1050°C,I although Mn3C becomes unstable when the temperature is reduced to 95O0C,' and can only be retained by rapid quenching. It is also known that a complete range of solid solution exists from Fe5Cz to M~SC~,~ although the stability range of carbides of the type (Fe,Mn)sCz as a function of the relative proportions of iron and manganese is not known. X-ray examinations of Oh-man's carbide3 and Spiegeleisenkristall,~ which have the approximate compositions (Fe3.67Mnl.33)C2 and (Fe3-,Mn,)C, where x lies between 0.4 and 1, respectively, have been made. The following carbides have also been studied: ] The lattice parameters determined during these investigations are listed in Table I. It is seen that carbides of the type (Fe,Mn)sCz have a monoclinic unit cell while carbides of the type (Fe,Mn)3C have an orthorhombic unit cell. It is evident that the variation of lattice parameters with manganese content is not linear for carbides of the type (Fe,Mn)3C. The coordinates of the atoms in (Fe2.7Mno.3)C have recently been determined by single-crystal analysis., The fractional atomic coordinates have been shown by Fasiska and jeffrey to be in good agreement withj those deduced from an earlier analysis of Fe3C by Lipson and etch.' However, it was impossible to determine whether iron and manganese atoms occupied ordered positions because of the small difference between the atomic scattering factors of iron and manganese. The atomic positions in Mn5Cz (Refs. 8 and 9) and Fe5C2 (Refs. 7 and 8) have been obtained only by comparisons made with the isostructural compounds P~SB~.' Since X-ray diffraction techniques were used in these investigations, accurate positioning of the carbon atoms, which have a low atomic scattering factor, was difficult. No attempt has been made to determine the atomic positions in the other carbides previously studied. It was felt that an investigation of the lattice parameters of a number of intermediate carbides of the types (Fe,Mn)sCZ and (Fe,Mn)& would be of interest. It seemed likely that a neutron-diffract ion study of such carbides would indicate whether ordering occurred between the iron and manganese atoms because of the large difference between the neutron-scattering cross sections of iron and manganese. It also seemed probable that such an investigation would provide a determination of the atomic coordinates of the carbon atoms. I) EXPERIMENTAL DETAILS Specimens, each weighing approximately 20 g, were carefully prepared according to the following proportions: The components were 500-mesh powders of 99.995 pct purity iron and spectroscopically pure carbon and a 200-mesh powder of 99.995 pct purity manganese. The component powders were intimately mixed by prolonged shaking, then each specimen was inserted into a spot-welded cylindrical container of tantalum foil, whose end was closed but not sealed. Each specimen in its envelope was then sintered at 1050° C for 24 hr in a thin-walled evacuated quartz capsule, such a time having been previously found sufficient for equilibrium to be attained.' Each specimen was then quenched in order to attempt to retain the high-temperature phase, as the literature indicates that transformations may occur on cooling. Debye-Scherrer X-ray photographs were taken of each specimen using a 114.6-mm-diam camera, Fig. 1, patterns 2 to 6. The exposure time was 6 hr using filtered iron radiation at a tube voltage of 40 kv and a tube current of 12 ma.

Jan 1, 1967

By Paul A. Farrar, Harold Margolin

The Ti-Al-V system has been delineated from 50 to 100 wt pct Ti and front 600 to 1400°C by X-ray and ntetallographic techniques. Isothermal sections were delineated at 600, 700, 800, 900, 1000, 1100, 1200, 1300, and 1400°C. X-ray and metallographic evidence indicated the presence of two phases and in addition to those reported by previous investigators of the ternary system'-3. T HE titanium-rich region of the Ti-Al-V system as originally proposed by Rausch et UZ, and Jordan and Duwez3 was based on the binary Ti-Al diagram as proposed by Bumps et uZ. As additional phases have been shown to exist5-' in the region previously thought to be all a, the titanium-rich region of the Ti-Al-V system is open to serious question. Therefore, in order to determine the effect of the indicated changes in the Binary Ti-Al system on the ternary Ti-Al-V system the present investigation was initiated. EXPERIMENTAL PROCEDURE The experimental procedures in this investigation are the standard techniques used in the study of titanium-alloy systems which have been described in detail previously.1° Consequently, only details pertinent to the present work are discussed. The alloys employed for the delineation of this system were prepared from titanium obtained from the Bureau of Mines (73 BHN) 99.99 pct Al and 99.7 pct V, by the consumable arc-melting technique. The titanium was premelted into buttons of 25 g because spattering during the first melt caused uncontrollable loss of alloying constituents. Typical analyses of the material used have been reported elsewhere Attempts to hot roll the alloys prior to heat treatment were made on the first series of alloys prepared, but as the area of extensive hot workability was fairly restricted, see Table I, this practice was discontinued. The times of isothermal annealing are given in Table 11. A preliminary heat treatment of 96 hr at 1000°C was used prior to heat treatment at lower temperatures. The standard techniques used for polishing specimens involved belt-grinding, grinding on emery paper, polishing electrolytically, and etching with Remington "A" etch. In the low-alloy region it was found that the oRo etch, developed by Ence and Margolin,o gave better contrast between phases. Where this procedure did not differentiate between phases clearly, the method of stain etching developed by Ence and was used. It has been previously reported15 that filing of titanium alloys is not desirable for producing X-ray powders, since the powder becomes contaminated by the file material. Therefore, for those samples not brittle enough to Crush, the procedure described below was used. The specimen was wrapped in molybdenum sheet and placed in a vacuum system and evacuated to 0.03 p. Palladium-pur if ied hydrogen was then admitted to the system until a partial pressure of 5o Cm of H was reached. The specimen was heated in the system to the temperature of original heat treatment and was slowly cooled over a period of 3 hr to 400°C while the partial pressure of hydrogen was maintained. The sample was removed from the system after it had completely cooled and was crushed to a powder of 230 to 270 mesh. The powder, wrapped in molybdenum sheet, was dehydrogenated at the temperature of original heat treatment until a partial pressure of 0.03 p was maintained in the system for at least 1/2 hr. The tube containing the powders was quenched in iced brine while still connected to the vacuum system. After dehydrogenation, the powder, except for the

Jan 1, 1962

By P. Marier, T. R. Ingraham

When cylindrical powder compacts of nickelous oxide (NiO) are heated in an equilibrated stream of SO3, SO,, and 02, in the temperature range 500°to 800°c, tlickelous suljate (NiSO4) is formed as an adherent layer on the oxide. The reaction is diffusion-controlled, with an activation energy of 13 ± 3 kcal per mole. When cylindrical powder compacts of NiSO4 are heated in a stream of dry nitrogen in the temperature range 1000 0to 11500C, NiO is formed at a well-defined interface between the sulfate and oxide. The interjhce migrates into the sulfate at a constant rate at a constant temperature and gas flow. The reaction rate increases with increasing gas flow and decreases with increasing partial pressure of SO3 in the gas stream. Resolution of the partial-pressure data with a Lang-itzliir Adsorption Isothern suggests that about 80 pct of the NiO interface is covered with SO3. The heat of adsovption is about 68 kcal per mole. The activation energy of the decomposition process is 61 ± 3 kcal per mole. MOST of the work reported on the formation and decomposition of nickel sulfate is related to thermodynamics.1-3 No quantitative work has been reported on the decomposition process. The only kinetic work reported on the formation is that by Fletcher and shelef.4-6 whose main purpose was to study the effects of alkali metal sulfate additions on increasing the rate of nickel sulfate formation. They found that, in the absence of an additive, only small amounts of sulfate were formed and the kinetic data were difficult to interpret. However, they suggested that the sulfa-tion of nickel oxide is a diffusion-controlled process for which the activation energy is approximately 17 kcal per mole.6 In this paper, both the formation and decomposition reactions will be examined; and based on the effects of temperature, flow rate, interfacial area, and partial-pressure of sulfur trioxide, mechanisms and activation energies will be suggested for both processes. EXPERIMENTAL Material. The nickel source material used in all experiments was Baker and Adamson Reagent Grade NiSO4. 6H2O, for which the following analysis was supplied by the manufacturer: C1, 0.001 pct; NO3, 0.005 pct; Co, 0.02 pct; Cu, 0.005 pct; Pb, 0.002 pct; Fe, 0.001 pct: insol, 0.005 pct. The anhydrous sulfate was prepared by heating the hydrate at 420°C in a muffle furnace for 5 hr. Nickel oxide was prepared by decomposing the sulfate at 950°C over a period of 10 hr. Method. The technique used for measuring the rates of formation and decomposition was developed earlier in these laboratories.7-8 The method is based on the observation that the kinetic parameters of a reaction can be established in a flow system, with specimens prepared by compacting powder to a uniform pellet shape. The results are identical with those established with solid polycrystalline specimens or single

Jan 1, 1967