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By P. Hadzeriga

There are two places in the world where potash, trade name for potassium chloride, is economically recovered from naturally occurring brines by solar evaporation. One is at the Dead Sea and the other at Wendover, Utah. American Potash and Chemical at Trona, Calif. recovers potash from natural brines, but uses fuel to accomplish evaporation. Solar evaporation is always desirable, because of low costs, however artificial evaporation may be economical if a group of very valuable salts are recovered. This is the case for the American Potash operations at Trona. Solar evaporation is limited by low working temperatures, which in most areas of the world is between 18 and 45°C. In many cases the average working temperature is about 25°C. However, solar evaporation will have to accommodate itself to the highs and lows of each 24 hour period, and to the different average temperatures during the months of the year. Therefore, solar evaporation, although more economical than artificial evaporation, has a tem- perature limit which greatly reduces the chances of its application. The feasibility of solar evaporation as a means of recovery of values from a particular brine, may be evaluated by the use of phase diagrams showing the several components present. This paper is restricted to the five component system: C1-, SO4=, Na+, K+, Mg++, and H2O, which correspond to brines found at Wendover, Utah, the Great Salt Lake, and sea water bitterns. THE BONNEVILLE OPERATION AT WENDOVER, UTAH For more than 25 years Bonneville, Ltd., now a division of Standard Magnesium and Chemical Co. (recently acquired by Kaiser Aluminum and Chemical Corp.), has been recovering potassium chloride from the brines found in the desert area just east of Wendover, Utah. Solar evaporation of the brines is possible as a consequence of relatively low precipitations (year average: 4.8 in.), and of dry and hot summer months. The brine, collected by a series of approximately 67 mi. of ditches crossing the desert, is fed into solar evaporation ponds. Evaporation which takes place from around the middle of May to about the end of September, permits the crystallization of approximately 90% of the originally present NaCl on what is called the "General Pond Area". Further evaporation,

Jan 1, 1964

By Edward Saibel

THE object of this study is to investigate the effect of prior tensile strain on the fracture stress of a metal. This is done in a theoretical manner starting from the point of view developed by the author in his thermodynamic theory of the fracture of metals. The results are compared with experimental findings and a rational interpretation is given to work that shows the variation of fracture stress with prior tensile strain. THEORY OF FRACTURE In the thermodynamic theory of the fracture of metals developed earlier,1 it was shown that a critical strain energy per unit volume exists. This is characteristic of the material and may be calculated from basic thermodynamic data. When the area under the flow curve reaches this characteristic value, fracture occurs. The general criterion for fracture is expressed in the form u ± uo = JLm?AV/V [1] where Lm, is the latent heat of melting of the unit volume, ?V/V is the ratio of the change in volume of the unit volume to the original unit volume on passing from the solid to the liquid state, [uo] is an initial energy density, and J is a conversion factor, which changes energy from heat to mechanical units. As a first approximation, it will be assumed that the stress-strain curve is the straight line that extends from the point of maximum load onward, extrapolated back to the axis of zero strain, for example, line AC of Fig. 1. If the point of intersection of the straight line with the axis of zero strain is represented by so, and the slope of the straight line is p, the analytic form of the flow curve is [s = s + pd [2]] and the strain energy per unit volume evaluated from [JvdS] becomes (vsod + pd2/ 2). When this latter term reaches the critical value JLm?V/V (designated hereafter by M), it is assumed that fracture occurs. This leads to the following expression for the fracture stress: [s1 = \/C r.2 + 2Mp [31] The strain at fracture may be calculated from Eqs 2 and 3. It is assumed in this paper that the initial energy density is either zero or that it may be neglected. Furthermore, the complicated states of stress and of strain existing in the necked region of the tensile specimen after "necking" has occurred will also be neglected for the present, so that average conditions will be assumed to prevail. FLOW AND FRACTURE CURVES Ludwig2 attributed to materials two fundamental properties: (I) a resistance to flow and (2) a resistance to fracture. He reasoned that at each instant the

Jan 1, 1947

By Paul A. Farrar, Felix Ermains, Harold Margolin

The systems Ti-Crand Ti-Vhave been reinvesti-gated in the region up to 40 wt pct alloying addition using both conventional and rapid quenching techniques. The Ti-Cr eutectoid temperature was determined to be at 667° & 10° C and 14.5 wt pct Cr. The solubility of the Cr in a Ti was found to be less than 1 pctat 700"C. The P transus of the Ti-V system was found to be depressed to 510°C at 40 wt pct V and the solubility of V in a Ti was found to be less than 2 wt pct at 700°C. Investigation by a. d. McQuillan1-3and m. k. McQuillan4 on the systems Ti-Co, Ti-Cr, Ti-Cu, Ti-Fe, Ti-Mn, Ti-Ni, and Ti-V has cast doubt as to the position of the ß/a + ß boundaries in many of these systems. Their investigations were carried out using hydrogen pressure and/or rapid quenching experiments, as opposed to the conventional quartz capsule techniques employed by most other investigator.'" By these methods, the ß/a + ß boundary was found to be lower than that obtained by conventional techniques in all except the Ti-Fe system. In the latter, the ß/a + ß boundary was essentially the same as the boundary obtained by conventional technique.7' On the basis of rapid quenching results in the Ti-Cr system, M. K. McQuillan4 placed the eutectoid temperature below 550°C whereas other investigations using conventional techniques had placed the eutectoid variously as between 650' and 700°C,5 between 675' and 700°C,6 between 650" and 675°C,7 at 670°C,8 and above 625"C.la9l3 In order to check these results, a reinvestigation of four of the systems was undertaken using both conventional and rapid-quenching techniques. The Ti-Fe and Ti-Mn systems will be dealt with in anoth er paper, with only the Ti-Cr and Ti-V systems being discussed here. EXPERIMENTAL TECHNIQUES Alloys employed for the delineation of the systems under investigation were prepared from iodide titanium sheet capsules containing the alloying materials,

Jan 1, 1962

By J. M. Dupouy, R. A. Rawe, M. B. Bever

The aging characteristics of a titanium alloy containing 13 pct V, I1 pct Cr, and 4 pct A1 have been investigated by hardness measurements, X-ray diffraction, and metallography. The P phase decomposes into 0 + a, and 0 + a, + TiCr, above about 1050°F; below this temperature a transition phase, believed to be w, precipitates first, followed by a, and TiCr,. The observed hardening is attributed to these reactions. Cold working of solution-treated specimens accelerates hardening and raises the hardness level attained. A TTT diagram is proposed. NEW titanium-base alloys, designated as "all-beta," have recently been developed. These alloys contain large amounts of P-stabilizing elements such as molybdenum, chromium, or vanadium. When cooled from the solution temperature, they consist only of P; in particular, the martensitic a,' phase does not form.

Jan 1, 1961

By J. R. Long, E. T. Hayes, D. C. Root, R. S. Dean

The U. S. Bureau of Mines has recently reported on the development of a process for preparing pure ductile titanium in substantial quantities1 and on the physical properties that may be attained in the metal, when consolidated by powder metallurgy methods and fabricated by certain hot and cold-working procedures.2 The high physical properties (Table I), combined with excellent corrosion resistance and light weight, will lead no doubt to appropriatc applications of the metal. In any application, methods of joining will be of considerable importance. The relatively high activity of the metal toward the common gases raises the question of weldability and conditions that might be required for successful welding. Since hydrogen, oxygen, and nitrogen embrittle the metal, it should be protected from these gases at elevated temperatures. This was demonstrated by a few preliminary trials of arc, gas, and resistance welding. In these trials only the resistance method proved to be immediately- applicable. While atomic: hydrogen welding of titanium may be successful in some instances, a considerable amount of development work will be required to prove its worth. In addition, it would be suited only to small assemblies that could be heated subsequently in a high vacuum to remove embrittling hydrogen. Heli-are methods likewise would be limited to small assemblies, which could be completely protected by a helium atmosphere. It was quite apparent that titanium required more protection than was afforded by the normal flow of helium gas used for welding magnesium and aluminum. The hot metal is attacked by oxygen and nitrogen, and the rapid diffusion of the oxide into the metal prevents the formation of a protective coating and requires the helium atmosphere to be maintained until the weld has cooled nearly to room temperature. The preliminary work indicated that titanium could be successfully spot-welded without deterioration of the metal and that the microstructures of the welds were normal, exhibiting good bonding, and no oxidation. The high resistivity of titanium (53 microhms per cu. cm.) suggested that it would behave somewhat like stainless steel and allow considerable latitude in the several welding variables. The results reported here are intended to give a general picture of the effects of varying welding current, welding time, and tip pressure on single spot welds made on several different thicknesses of titanium sheet. The work was undertaken to demonstrate the feasibility of welding titanium rather than as an exhaustive study of spot welding. There are, therefore, a number of factors that will require further investigation to establish the specific controls required for actual applications.

Jan 1, 1947

By J. R. Long, R. S. Dean, D. C. Root, E. T. Hayes

The U. S. Bureau of Mines has recently reported on the development of a process for preparing pure ductile titanium in substantial quantities1 and on the physical properties that may be attained in the metal, when consolidated by powder metallurgy methods and fabricated by certain hot and cold-working procedures.2 The high physical properties (Table I), combined with excellent corrosion resistance and light weight, will lead no doubt to appropriatc applications of the metal. In any application, methods of joining will be of considerable importance. The relatively high activity of the metal toward the common gases raises the question of weldability and conditions that might be required for successful welding. Since hydrogen, oxygen, and nitrogen embrittle the metal, it should be protected from these gases at elevated temperatures. This was demonstrated by a few preliminary trials of arc, gas, and resistance welding. In these trials only the resistance method proved to be immediately- applicable. While atomic: hydrogen welding of titanium may be successful in some instances, a considerable amount of development work will be required to prove its worth. In addition, it would be suited only to small assemblies that could be heated subsequently in a high vacuum to remove embrittling hydrogen. Heli-are methods likewise would be limited to small assemblies, which could be completely protected by a helium atmosphere. It was quite apparent that titanium required more protection than was afforded by the normal flow of helium gas used for welding magnesium and aluminum. The hot metal is attacked by oxygen and nitrogen, and the rapid diffusion of the oxide into the metal prevents the formation of a protective coating and requires the helium atmosphere to be maintained until the weld has cooled nearly to room temperature. The preliminary work indicated that titanium could be successfully spot-welded without deterioration of the metal and that the microstructures of the welds were normal, exhibiting good bonding, and no oxidation. The high resistivity of titanium (53 microhms per cu. cm.) suggested that it would behave somewhat like stainless steel and allow considerable latitude in the several welding variables. The results reported here are intended to give a general picture of the effects of varying welding current, welding time, and tip pressure on single spot welds made on several different thicknesses of titanium sheet. The work was undertaken to demonstrate the feasibility of welding titanium rather than as an exhaustive study of spot welding. There are, therefore, a number of factors that will require further investigation to establish the specific controls required for actual applications.

Jan 1, 1947

By C. A. Hartnagel, D. H. Newland

Detailed production statistics listing the operations according to producing sands, districts, etc., are not available for New York State and are scarcely obtainable without extraordinary effort and expense, hardly warranted by the current rate of developments. The oil industry is practically stabilized, so far as exploration for new sources of supply are concerned; no new pools have been tapped in the last 25 or 30 years. There is little prospect of extending the boundary of the oil fields beyond their present limits, though possibly some additional reserves may be found below the present productive sands. Natural gas, on the other hand, is not restricted to such confined areas. Drilling for gas has been fairly active, under the stimulation of some important finds in formations that previously were overlooked. The year's field operations will be covered somewhat fully. Oil production, which has been steadily advancing for a number of years, showed a further moderate gain in 1936. The output for 11 months (figures for December are not yet available) was 4,217,000 bbl., indicating a total for the year of around 4,600,000 bbl. The increase was about 10 per cent, a rate maintained for some time. Prices were more satisfactory than in the preceding five years, with an advance to $2.57 a barrel before the year's close. New York State yield is all paraffin-base, in the same class with high-grade Pennsylvania oil. Most of the output is now obtained by the water drive, which has given a new lease of life to the fields and promises to bring the total to about 200,000,000 bbl. before the known acreage has been exhausted by this method. Before its introduction the annual production was under 1,000,000 bbl. a year. The fields cover an aggrcgate area of 55,000 acres, with some 17,000 wells in operation. Development Exploring for natural gas in New York in 1936 outside of the old established pools continued actively, as in the previous year. There was an increase in total initial production. Operations were conducted in nine counties of the central and western parts of the state, and 43 wells

Jan 1, 1937

By Arthur McKee

As HEAT is the controlling factor in all smelting operations, it will be .most helpful to make a new set of calculations on the basis of a .unit of fuel burned at the tuyeres to carbon monoxide. This ties together the only two factors in this operation that seem to be constant with respect to each other-the fuel at the tuyere and the air or its oxygen content. If our usual smelting operations, using natural air heated to reasonably obtainable temperatures, furnish sufficient heat above this critical temperature for the purpose, it is doubtful whether additions of oxygen will be of marked benefit. A unit of fuel will not produce a single heat unit more if burned with pure oxygen than if burned with natural air and less heat will be available per unit of fuel by the amount of heat that is carried in by the preheated nitrogen in the natural air of the blast. This is more readily apparent if considered in connection with a heat balance sheet per unit of fuel at the tuyere. The heat available in the stack, as shown by the committee's report, is less by reason of the lower fuel consumption per unit of output assumed in this calculation. The balance sheet for enriched air shows a shortage of the amount of heat usually carried in with the blast; also a lack in the hearth of sufficient heat to melt the 18 per cent. additional metal and slag and in the shaft to the extent of the shaft heat required to heat the 18 per cent. additional stock to the melting point. These heat deficiencies are provided for by the largely increased conversion of carbon monoxide into carbon dioxide, which is assumed, as shown by the following figures: Calculation for natural air: Carbon dioxide 18.4 per cent. (after having eliminated the carbon dioxide from limestone) and 20.8 per cent. of carbon monoxide. Calculation for oxygen-enriched air: Carbon dioxide 28.4 per -cent. and carbon monoxide 23.2 per cent. (no carbon dioxide from stone as lime is charged instead).

Jan 11, 1924

By D. Y. Geng, S. S. Peng

Surface subsidence of two longwall panels, one with a private residence and the other with an arch bridge, was monitored over a period of 1 to 1' ½ years. Surface subsidence data were analyzed in terms of zone of advance influence and delay angle of maximum subsidence velocity. The variational characteristics of both features coincide with the periodic weighting at the advancing longwall face. Surface heaving in the subsidence process can also be attributed to periodic weighting. It was found that residential damages occurred when subsidence velocity exceeded 4.5 mm/day (0.15 ft/day). The effects of locating structures on the panel center and near the gob edges are illustrated. The effect of mining on ground water was also discussed. Finally, methods of reducing structural damages are recommended.

Jan 1, 1984

By Lawrence Adler

The authors are to be complimented on using a novel and potentially helpful technique to analyze the effects of mine roof trusses. However, some criticisms of their application and analysis seem appropriate to further its acceptance. This discussion will deal with the normal structural analysis format covering: 1) material. 2) load, 3) structure, and 4) analysis. It will then briefly review the testing procedures and finally cover miscellaneous items. That the analytical and testing results admittedly disagreed by several orders of magnitude, indicates a need for improved understanding. The introduction of data determined previously was not assisted by references to "Interim" or "Preliminary" reports. This material should have been concisely reformulated for the open discussions that Transactions encourage. In addition, many important simplifying assumptions are tacitly made without recognition, and much less, an attempted justification.

Jan 1, 1979

By W. C. Knopf, G. Samsel

For several years International Minerals & Chemical Corp. has used a radiation method to assay potassium content of products from potash and feldspar beneficiation. The procedure is rapid, accurate, and inexpensive and is easily handled, if necessary, by nontechnical personnel. Data are presented to show the accuracies that may be expected if the technique is used for control of pilot plants or large- scale plants. Natural potassium is composed of three isotopes -K39, K40 and K41. Five other isotopes, artificially produced, have been detected. In natural potassium only the K40 isotope, with a half life of 1.4 x 109 years, is radioactive. Its modes of decay are beta and gamma rays, positrons, and x-rays. Only the more abundant beta rays, however, are important in radiation measurements using geiger tubes.

Jan 10, 1958

Discussion of the paper of DOUGLAS BUNTING, presented at the New York meeting, February, 1915, and printed in Bulletin No. 97, January, 1915, pp. 1 to 21. ARTHUR HOVEY STORRS, Scranton, Pa.-I know something about accidents Nos. 4 and 8. At the Fuller mine there was no disturbance of the surface in connection with either of those accidents, there was no surface settling, nor signs of sand in the mine, and seemingly the water all came from a subterranean basin or water-bearing stratum overlying the Six Foot vein. A similar thing was shown, in an accident not referred to in Mr. Bunting's table, at the Avondale, where we had an inflow of water, as high as 12,000 gal. a minute, for a considerable period. Regarding the second accident (No. 8) at the Fuller mine: after the first inflow of water (No. 4 of the table), the mining was abandoned in the Six Foot vein. A long slope was. driven in an underlying seam, and when this had reached a point about 2,000 ft. southeast of the place where the first inflow of water occurred, and where the bore holes show there was apparently sufficient rock covering for the Six Foot vein, a rock plane was driven up to the upper vein (Six Foot) and one afternoon this exposed the coal. During the following night the inflow of the water occurred. There were absolutely no workings at this point so that no disturbance of the overlying rocks could have occurred. The result of the inflow of water was to fill up the entire lower-vein workings in about two or three clays and caused the abandonment of the mine. After several years, considerable time and money were spent in an effort to hoist the water from the shaft and mine workings, with varying, but in the main rather indifferent, success until, clue to the breaking of one hoisting rope, the engineer pulled the other hoisting tank up through the tower and down on to the engine, making a complete wreck of the whole plant. It was then decided to allow the mine to soak and it is still doing so, other portions of the property being mined from adjoining collieries.

Jan 5, 1915

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons. ) Position in sales department is open for a mining engineer with experience in mine ventilation and possessing some knowledge of fan design; one competent to lay out ventilating systems to meet various conditions. No. 2. A large company manufacturing mining machinery has an opening in one of its Western agencies for a young mechanical engineer who has had some experience in designing along general machine shop lines, and who is familiar with cost systems. No. 3. A large university desires to secure a prominent metallurgist for a vacant professorship in metallurgy. No. 4. Opening at a mine in New Jersey for a technical graduate to begin work as chairman on the surveying squad. Salary $50 per month to start. No. 5.

Jan 11, 1913

By John Griffen, David H. Davis

Much of the ground to be covered by this paper was ably covered by a paper presented by Messrs. Morrow and Jordan1 before a joint meeting of the Iron and Steel Section of the Engineers Society of West-ern Pennsylvania and the A.I.M.E. Pitts-burgh Section at Pittsburgh in the spring of 1940. As that paper was not published, the present authors have availed them-selves of Mr. Morrow's kind permission to use information given therein. Similar figures for the latest years available have been added to many statistics originally presented. It is unfortunate that Mr. Jordan's death removes his stimulating guidance and help, which the authors would have welcomed and have found invaluable in the past. One interested in the Pittsburgh seam should not fail to read the exhaustive and authoritative paper by Eavenson2 presented in 1938. As Allegheny, Fayette, Greene, Washington, and Westmoreland Counties contain practically all the reserves and furnish nearly all of the production from the Pittsburgh seam in Pennsylvania at the present time, this area only is intended when reference is made to the Pittsburgh seam in Pennsylvania. On much of the seam in Greene and Washington Counties, which contain a large proportion of the total reserves, insufficient data are available to determine the detailed characteristics of the seam with any degree of finality. It is hoped that the data presented here will fairly well indicate the probable characteristics. Economic Importance of the Pittsburgh Seam The Pittsburgh seam in Pennsylvania is of primary importance as a coal resource, not only because of its substantial reserves but because it contributes such a large proportion of the coal used in the country and an even larger proportion of that used in the manufacture of coke. Mr. Ashley3 placed the estimated recoverable reserves (1935) of the Pittsburgh coal bed in Pennsylvania at 7,500,000,000 tons.* Although a considerable portion of this tonnage is not now suitable for coking coal, because of its high sulphur content, undoubtedly the supply of coking coal will last for many years and that not suitable for coking will furnish industry with an ample supply of energy. In attempting to assess the contribution of the Pittsburgh seam to total coal production and to that of coal used in making coke, one finds that the statistics published annually by the U. S. Bureau of Mines, Minerals Yearbook, do not give tonnages classified as to seams but only as to districts or states and counties. However, it happens that, at present and during much of the

Jan 1, 1944

By David H. Davis, John Griffen

Much of the ground to be covered by this paper was ably covered by a paper presented by Messrs. Morrow and Jordan1 before a joint meeting of the Iron and Steel Section of the Engineers Society of West-ern Pennsylvania and the A.I.M.E. Pitts-burgh Section at Pittsburgh in the spring of 1940. As that paper was not published, the present authors have availed them-selves of Mr. Morrow's kind permission to use information given therein. Similar figures for the latest years available have been added to many statistics originally presented. It is unfortunate that Mr. Jordan's death removes his stimulating guidance and help, which the authors would have welcomed and have found invaluable in the past. One interested in the Pittsburgh seam should not fail to read the exhaustive and authoritative paper by Eavenson2 presented in 1938. As Allegheny, Fayette, Greene, Washington, and Westmoreland Counties contain practically all the reserves and furnish nearly all of the production from the Pittsburgh seam in Pennsylvania at the present time, this area only is intended when reference is made to the Pittsburgh seam in Pennsylvania. On much of the seam in Greene and Washington Counties, which contain a large proportion of the total reserves, insufficient data are available to determine the detailed characteristics of the seam with any degree of finality. It is hoped that the data presented here will fairly well indicate the probable characteristics. Economic Importance of the Pittsburgh Seam The Pittsburgh seam in Pennsylvania is of primary importance as a coal resource, not only because of its substantial reserves but because it contributes such a large proportion of the coal used in the country and an even larger proportion of that used in the manufacture of coke. Mr. Ashley3 placed the estimated recoverable reserves (1935) of the Pittsburgh coal bed in Pennsylvania at 7,500,000,000 tons.* Although a considerable portion of this tonnage is not now suitable for coking coal, because of its high sulphur content, undoubtedly the supply of coking coal will last for many years and that not suitable for coking will furnish industry with an ample supply of energy. In attempting to assess the contribution of the Pittsburgh seam to total coal production and to that of coal used in making coke, one finds that the statistics published annually by the U. S. Bureau of Mines, Minerals Yearbook, do not give tonnages classified as to seams but only as to districts or states and counties. However, it happens that, at present and during much of the

Jan 1, 1944

By Wm. Hamilton Merritt

IN this paper, which I have the honor to submit to the Institute, it is my intention to treat especially of that part of the North Staffordshire field which converges to a long tongue in the neighborhood of Congleton, and which includes the villages of New Chapel, Ford Green, Norton, Biddulph, Bradley Green, Gillow Heath, and the immediate vicinity. My object is not so much to give a minute description of the geology or systems of mining and smelting, as by a general review, some idea of the extraordinary facilities for the production of excellent iron, which have enabled this district to maintain its position more successfully than any of its rivals against the late depression in trade. The North Staffordshire coal field has the Cheshire and Lancashire fields some thirty-five miles to the north, those of Derbyshire and Nottinghamshire forty miles to the east, those of South Staffordshire and Shropshire, about thirty miles to the south, and the Denbighshire and Flintshire fields some forty miles to the west. It is highly probable that the coal continues under the new red sandstone to the Western and Southern fields as the dips on both sides, and absence of large faults, make it impossible to come to any other conclusion. In a section of this coal field, from Chatterly to Whitfield, thirty-two workable seams of coal are shown, of an aggregate thickness of 130 feet, varying from 2 feet 6 inches to 7 feet, and thirteen seams of ironstone, 24 feet, averaging from 2 to 4 feet. All of these seams have been minutely described in a paper by Mr. Charles J. Homer, read in 1875 before the British Iron and Steel Institute. In the northern part, to which I especially wish to direct your attention, the beds lie in a V-shaped basin, the underlying millstone grit and Yoredale rocks rising and forming escarpments on either side of the valley containing the coal. Throughout this district, at the outcrop of the coal, there are indications of old workings. A shaft 4 to 5 feet in diameter reaches the coal at about 14 yards from the surface, and from it the coal has

Jan 1, 1880

By Gilbert E. Doan

WHEN metallurgists and other engineers meet their college classmates or former teachers, the conversation will frequently become reminiscent and finally turn to engineering education. These graduates have tested the value of their college training in the hurly-burly of the outside world so respectful attention is due their opinions, which, strangely enough, fall into two opposite categories. A member of one group expresses a deep-seated conviction that engineers should have a fuller foundation of physical chemistry, another asks for a more thorough training in mathematics, others wish a more thorough grounding in refractories, a series of courses in petroleum engineering, or in electric welding. Each alumnus of this group

Jan 1, 1937

By M. Gensamer

ONLY recently has it been realized that preferred orientations are common in hot-rolled steels. In a recent paper, N. P. Goss1 stated that hot-rolled mild steel exhibits a texture different from that charac-teristic of cold-rolled steel. No complete study of these hot-rolling textures has been reported using the pole-figure method of Wever. The material used in the work reported in this paper was the same material used by Gensamer and Mehl2 in a recent study of preferred orientations in cold-rolled steel, to which reference may be made for the composition and thermal history of the steel. Automobile-body sheet bar, 4 in. thick was hot-rolled at two temperatures, 780° and 910° C. (1436° and 1669° F.). (These temperatures refer to the tempera-ture of the furnace in which the steel was heated.) After each pass the steel was returned to the furnace and held there long enough to return to temperature. Although no accurate method was used to measure the temperature after each pass, it was estimated by color that only a slight drop in temperature occurred. In order to determine the effect of any preferred orientation that might have persisted through the normalizing treatment, one specimen at each temperature was rolled in the same direction as the original working direction and the other at right angles to it. The total reduction in each case was 85 per cent, the specimens having been reduced from 0.250 to 0.0375 in. in five passes. Final cooling was in air. Pinhole reflection photograms were taken of all four specimens, with the rolling direction vertical and the X-ray beam at an angle of 7° with the transverse direction (the transverse direction is defined as that direction in the rolling plane perpendicular to the rolling direction). These photograms, taken with a Me target at 35 kv., are reproduced in Figs. 1, 2, 3 and 4. They show that a more pronounced texture was developed by the low-temperature rolling (780° C.), and that of the two

Jan 1, 1936

By I. N. Knapp

Introduction.—The spccial object of these notes is to describe the mixing, testing, and use of mud-ladened water for rotary drilling in such a way as to make them helpful to the driller, the operator, or the engineer in solving his own special drilling problems. The structures, apparatus and tools used are indicated in a general way. No attempt is made to describe the art of rotary drilling; only such descriptions as are necessary to make plain the use of mud are given. The information is the result of actual experience in drilling in Coastal Plain formations. The materials encountered in the wells drilled were unconsolidated sands, gravels, and clays, in which thin layers of sandstones, shell conglomerates, and shales began to appear at about 1,200 ft, in depth, although one well was drilled to 3,018 ft. without encountering any cemented or indurated materials. Unusual Conditions.—-The general surface of the ground where the drilling was done being hardly a foot above mean tide, and the daily tidal variation being about 15 in., it was found necessary to plank over the sod surface with 3-in. plank to work from. A 30 by 30 ft. planked area was sufficient to carry the derrick with equipment and 2,500 ft. of 4-in. drill pipe stacked in it. The derrick was set up 3 ft. on cribbed blocking arranged to spread the load over the planking. The engine, bailers, and pipe yard were also carried on 3-in. planking. Drilling 0utfit.—This consisted of a derrick, 20 by 20 ft. and 84 ft. high, two 35-h.p., "oil country" boilers, one double 8 1/4 by 10 in. reversible engine, two 10 by 6 by 12 in. duplex mud pumps, one 15-in. rotary, "hoisting works" with chain drive, hoisting block with line, crown block with pulleys, rotary jetting swivels, hose, complement of tools, pipes and connections, and a mud mixer, with engine. Hydraulic Rotary Drilling Method.—This method of drilling is an adaptation of Fauvelle'sl invention made in France in 1833 for drilling

Jan 1, 1915

By Leonid V. Azároff, H. N. Murty

In the course of investigating the soft X-ray absorption spectra of Ni-A1 alloys, Das and ~zfiroff' observed an anomalous brittleness in solid solutions containing 3 to 5 at. pct Al. The brittle alloys also had anomalously larger lattice constants' and the fine structure at the nickel K edge of an alloy containing 3.96 at. pct A1 unexpectedly resembled that of NiA1 more closely than that of a solid solution containing 5.51 at. pct Al. This led them to suggest the possibility that short-range ordering was produced during the homogenization anneal to which each specimen was subjected, similar to that observed in dilute solutions of vanadium and of chromium in nickel: as the principal cause of embrittlement. It was decided to repeat the above measurements on several alloys in this composition range in order to test the above hypothesis and to establish the effect of heat treatment on the alloys' properties. Three solid solutions in this range were prepared containing, respectively, 3.16, 4.00, and 4.54 at. pct Al, in addition to alloys containing 6 and 9 pct. All samples were annealed in vacuum at 1800°F for 100 hr and then furnace-cooled to room temperature, as in the original study. The lattice constants of these alloys are shown by open circles in Fig. 1 and can be seen to fit quite closely the curve established by the previously measured values, indicated by solid circles. (The experimental errors are of the order of the size of the circles, +o.oo~R.) The three alloys containing 3 to 5 at. pct A1 were found to be quite brittle, as previously reported. In order to test the possibility of ordering, these three solid solutions were again heated to 1800°F and, following a few hours at that temperature, were quenched directly to room temperature. All three alloys lost their brittleness. In order to verify the proposed ordering hypothesis, it was decided to subject each sample to several cycles of quenching and annealing (disordering and ordering). After some experimentation, it was established that reproducible results could be obtained by anneal-

Jan 1, 1968