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By R. J. Sherman, M. R. Achter

IT has often been reported that coatings may strengthen single crystals and polycrystalline specimens of coarse grain size. This note reports the effect of a surface layer of fine grains on the creep-rupture properties of coarse grained nickel 99.8 pct pure. Sheet specimens were machined from cold-rolled material, finished by surface grinding and annealed at 1230°C in vacuum for 4 hr. Half of them were re-ground on faces and sides and annealed at 925"C for 1 1/4 hr. The double grind-anneal treatment produced a structure consisting of a surface layer of fine grains of 0.02 mm diam on a coarse-grained substrate of grains of 0.40 mm diam. Comparison with specimens which received only the single grind showed that the second grind-anneal did not alter the structure of the substrate. Several modifications were made in specimen design to eliminate erratic rupture behavior outside of the gage length. In the final design the gage section, oriented parallel to the rolling direction, was 1.00 in. long, 0.4 in. wide, and 0.0625 in. thick. End tabs were pinned in place. Although other configurations (welded end tabs, transverse orientation, and wider gage section) showed similar effects of a layer of fine grains, because of the erratic rupture behavior, only the data from the final design are reported here. Creep tests were performed at 650°C in air and in a vacuum of 10~5 mm Hg. Creep rates were measured from the movements of the lever arm. Since the broken sheet specimens could not be fitted together, elongations at fracture measured by means of gage marks, do not include the necked portions adjacent to the fracture. Results of the creep tests with and without the fine grained surface are given in Table I. An explanation for the lower strength in air than in vacuum has been proposed previously in terms of the reduction of crack propagation energy by gas adsorption.l In both environments the fine-grained layer produced a small decrease in minimum creep rate and, except for the shortest test in air, a substantial increase in rupture life. The elongation values at rupture, as they are measured here, do not demonstrate an appreciable effect of the grain structure but do show much smaller ductilities in air than in vacuum. Greater elongations maybe associated with the finegrained layer, however, especially in vacuum, in creep curves such as those in Fig. 1. Duplicate tests were not run to determine the re-producibility of the data. It is felt, however, that, in view of the consistent behavior, the prolongation of rupture life may be attributed to the effect of the fine-grained surface. In the data not reported be-

Jan 1, 1962

By L. Dudley Stamp

On April 1, 1937, Burma, formerly a province of the Indian Empire, was formally separated from India and became an independent unit of the British Commonwealth. In future, therefore, statistics of oil production in India will exclude Burma and those for Burma will be separately published. The last few years have been marked by noteworthy, almost spectacular, developments in the oil fields of Burma and the Punjab. In Burma these developments have been the proving of unexpected extensions of the existing fields and not the discovery of entirely new fields. The new extensions are important not only to Burma in giving a new lease of life to her fields, but also in general as stressing some interesting geological aspects hitherto neglected. Production The production of crude oil in Imperial gallons has been: Burma India 1934 254,760,070 67,265,210 1935 251,338,974 . 71,323,362 1936 265,656,393 69,241,504 1937 (eat.) 270,000,000 70,000,000 The Chindwin Fields.—The small field at Indaw continues to produce steadily about 3,000,000 gal. a year, but no really deep test has yet been successfully carried out and resources are thus not yet fully known. The remote location of the field, inaccessible except by river and situated 22 miles from the Chindwin 270 miles up that river from its junction with the Irrawaddy, has not encouraged active exploitation. The field is worked exclusively by the Indo-Burma Petroleum Co., Ltd. (I.B.P.), using now an automatic gas-lift system, and the company formerly refined the oil at a small refinery at Pantha on the river near by. The chief market was for kerosene in upper Burma. The refinery has now been closed. The oil is stored on the field during the low-water season

Jan 1, 1938

By Foster J. Witthauer

First mining operations in the Tyrone District, located just north of the Burro Mountains in Grant County, New Mexico, commenced in the 1870's. A major operation was undertaken by Phelps Dodge Corporation in the early 1900's when a 2,000 ton per day underground mine was developed and a gravity concentrator was built east of the mine and across the Continental Divide. It was during this time that the picturesque Tyrone townsite was built and occupied. In 1921, however, the underground operation was closed because of high operating costs and low demand for copper. The area was drilled extensively during the 1950's and in October 1966 Phelps Dodge announced the pending development of the new Tyrone with a large open-pit mine, a modern concentrator, suitable support facilities, and a new townsite to be located between the mine and Silver City. Stripping for the pit and construction of shop and milling facilities began in 1967. By the spring of 1969, ore was being stockpiled near the primary crusher. Operation of the concentrator on a 3-shift per day basis commenced on July 17, 1969. The concentrator as initially built had one primary, two secondary, and five tertiary cone crushers, two grinding sections of six ball mills each, two flotation sections, four filters, and four tailing thickeners. The capacity was about 30,000 tons per day. In 1971 and 1972, the capacity was increased to 48,000 tons per day by the addition of one secondary and two tertiary crushers, one section of eight ball mills, one flotation section, two filters, and four more tailing thickeners. Centralized automatic control was built into the original and expanded facilities to the greatest extent possible, considering the state of the art at that time. Installation of additional control

Jan 1, 1976

By C. H. Samans, G. F. Tisinai, J. K. Stanley

The times at which the first detectable amount of a phase forms at temperatures between 900° and 1800°F were determined. Both X-ray diffraction and metallography were used to detect a in highly strained filings; metallography alone to detect it in annealed bulk samples of six different types of stainless steels. The a phase was found to form in accordance with the C-type reaction curve in both austenitic and ferritic alloys. In filings of types 304, 347, and 446, a formed in a few hours, and in types 316, 309, and 310, it formed in a matter of minutes at temperatures corresponding to the knee of the C-curve. Only in the bulk type 309 steel, after 500 hr, and in the bulk type 310 steel, after as short a time as 25 hr at temperature, was n detected; in both instances at approximately the same optimum temperature as in the filings. The annealing temperature affected a phase nucleation only for the filings of type 304 and 347 steels, and for the bulk samples of type 309 and 310 steels. KNOWLEDGE of both the rate of nucleation and the rate of growth of the new phase is required for a complete description of metallurgical rate phenomena. However, data on the time for nucleation alone may frequently be useful in evaluating the tendency of commercial stainlcss steels to form s under various conditions. Very little correlated information of this type is available in the literature. Shortsleeve and Nicholson' indicate that s forms in ferritic 24, 27 and 30 pet Cr steels according to a C-type of reaction curve, and Emmanuel's' data for austenitic type 310 steel also suggest this type of solid state reaction. In addition, significant, though fragmentary, information has been given by Binder, Dulis and Smith,4 Payson and Savage,.; Guarneri, Miller, and Vawter,8 rerichs and Clark,7 Wilder,5 Lismer, Pryce, and Andrews,' Smith, Dulis, and Link,10 Dulis, Smith, and Houston," and Henry, Cordovi, and Fischer." The bearing of these data on this work is covered in the discussion. The purpose of this paper is to present such correlated data on s formation in AISI type 304 (18 pct Cr-8 pet Ni), 347 (18 pet Cr-10 pet Ni-Cb), 316 (18 pet Cr-12 pet Ni-2 pet Mo), 309 (25 pet Cr-12 pet Ni), 310 (25 pet Cr-20 pet Ni), and 446 (27 pet Cr) stainless steels. Materials and Test Methods X-ray diffraction and metallographic methods were used to determine the first appearance of the s phase in cold worked filings and in annealed bulk samples of seven steels, under various combinations of time and temperature. The rate of growth of the s particles was not determined. Commercial heats of six AISI steels and a low carbon laboratory experimental heat containing about 28 pet Cr were studied. Analyses are given in Table I. Because cold work greatly accelerates the nucleation of s particles, the relative rates of s nucleation in mechanically strained samples, i.e., filings through 120 mesh, were determined for direct comparison with those in annealed bulk alloys of the same composition.

Jan 1, 1957

NEW MEMBERS The following list comprises the names of those persons who became members during the period Apr. 10, 1916 to May 10, 1916. ALLEN, WILLIAM R.... Pres., Boston and Montana Development Co., Butte, Mont. BARKER, EDGAR EARL, Min. Engr. Mine Supt., Chile Exploration Co., Chuquicamata, Chile, S. Amer. BAYLESS, JOHN Z., Met. Engr Alaska Gastineau Min. Co., Thane, Alaska. BLACKWOOD, ARTHUR E., Mgr., Sullivan Machinery Co., 30 Church St., New York, N. Y. BREYER, FRANK G., Chief Testing Dept., The New Jersey Zinc Co., (of Pa.), Palmerton Pa. CARPENTER, JAY A., Mill Supt... . West End Cons. Mining Co., Tonopah, Nev. CORLESS, GEORGE BRADFORD, Geol., Missouri Bureau of Geology and Mines, Joplin, Mo.

Jan 6, 1916

Quarrying and crushing 500 tons of limestone plus burning some 240 tons of limestone per day are the two initial phases in the production of borax, soda ash, sodium sulfate and related chemicals at Stauffer Chemical Co.'s plant in Westend, Calif. These processing steps have been upgraded in recent years by the installation of new primary and secondary crushers, an 8 x 340-ft rotary kiln plus kiln feed, control and cooling components-all designed and manufactured by Traylor Engineering and Manufacturing Division of Fuller Co. As a result of this new equipment, a new product- quicklime-has been added to the West End product family and considerable reductions have been realized in fuel and manpower costs.

Jan 1, 1965

By L. P. Teas

Although 1930 has been a year of stagnation, proration and curtailment, the Gulf Coast has measured up to its tradition in the matter of interesting and significant discoveries. Only 2 domes and 7 new structural areas were brought into the producing column in 1930, whereas, in 1929, 13 domes and one structure were added to this list, yet a total of 14 new producing horizons were proved on various domes and structures. On 5 domes new flanks were successfully tested for commercial production. The year 1930 has shown at Barber's Hill that oil in commercial quantities may exist below salt or cap. Numerous wells have been drilled through cap, or even salt itself, into good producing sands. The past year has been particularly notable in the interest and in the number of deep holes drilled. Two wells have gone below 8000 ft. in each of the states of Texas and Louisiana, and in the two states together 14 wells have gone below 7000 ft At the beginning of the year only one well was producing below 6000 ft. in coastal Texas, while at its end, 19 wells were producing or had produced. Geophysical discoveries and activity on the Coast have waned and this type of work has moved further inland. The peaks of production at Pettus, Barber's Hill, Raccoon Bend, Refugio, Orchard and at Humble, in Texas; and at Lake Barre, Port Barre, Black Bayou, White Castle and Vinton in Louisiana, were seen this year. These were new peaks for Humble and Vinton, of course, these fields having previously gone through periods of peak flank production. In Table 1 the completions listed are for the entire month of December in both years. It is remarkable that in 1930, a year of overproduction and proration, there were actually more wildcat operations at its end than at the end of 1929; but it is gratifying that the operations in the proven fields were exactly one-half what they had been at the end of 1929. The price of A grade coastal crude, or oil below 25" Bé., has been cut from $1.30 at the beginning of the year to $1.00 at its close; and B grade, or oil above 25o Bé., has been reduced from a price range of $1.15 to $1.63 down to a range of from $0.75 to $1.22. In spite of these reductions there has been no proration program on the Coast. Systematic

Jan 1, 1931

By Thomas R. Mager

An in.t!estigation has been made of the equilibrium conditions at 1200°C in the reaction between hydrogen sulfide gas and sulfur dissolved in Fe-Si alloys From this the equilibrium constant, activity coefficient, and activity of sulfur in solution were calculated. A number of studies of the equilibrium of sulfur with iron and iron alloys have given closely agreeing results from which the activity and free energy of the dissolved sulfur may be found. Sherman, El-vander, and chipman1 discussed the significant researches of dilute solutions of sulfur in liquid iron prior to 1950, and the results of this study indicated that the relationship between the ratio of PH2S/PH2 in the environment and the percentage of sulfur in solution is not a linear one. Morris and williams2 studied the equilibrium conditions in the reaction between hydrogen sulfide gas and sulfur dissolved in liquid iron and Fe-Si alloys, and reported that silicon dissolved in iron has a pronounced effect on the equilibrium conditions. They found that the activity of sulfur in iron is increased by the addition of silicon. At a silicon content of 4 pet the activity coefficient of sulfur was about twice that for sulfur dissolved in pure iron. Sherman and chipman3 investigated the chemical behavior of sulfur in liquid iron at 1600°C through the study of the equilibrium: H2 + S = H2S; K = PH2S/PH2 . 1/as [1] From the known equilibrium constant of the reaction between H2, H2S, and S and the experimental data, the activity of sulfur in the melt was determined. They found that the activity coefficient of sulfur defined as fs = as/%s is increased by silicon and decreased by manganese. Morris4 and Turkdogan5 also reported that manganese decreases the activity coefficient of sulfur in liquid iron and iron-base alloys. A recent technique of sulfur analysis developed by Kriege and wolfe6 of the Westinghouse Research Laboratories permits an accurate sulfur analysis of 0.5 * 0.2 ppm in the range of 0.1 to 3 ppm, whereas in the range of 3 to 50 ppm the accuracy is ±1 ppm. This technique of sulfur analysis was utilized in this experiment. Previous unpublished data reported that sulfur analysis by the combustion technique was not accurate below 20 ppm. EXPERIMENTAL PROCEDURE Five 5-lb ingots of high-purity Fe-Si were prepared. Three of these ingots were prepared without the addition of manganese but with a variation of silicon contents from 2 to 4 pet. The remaining two ingots contained 3 pet Si with the addition of manganese. Ingots were made at each of three silicon levels: 2, 3, and 4 pet. No alloys were made with less than 2 pet Si since below approximately 1.8 pet Si the binary alloy exhibits a to ? transformation. The two additional ingots of 3 pet Si-Fe were made at each of two manganese levels: 0.20 and 0.50 pet. To minimize the effects, if any, of impurities on the activity of sulfur on Si-Fe, the best metals available were used for melting. All ingots were vacuum-melted in magnesium oxide crucibles. After obtaining samples for chemical analyses, the ingots were processed. This consisted of hot rolling and subsequently cold rolling the alloys. Each ingot was hot-rolled at 1000°C, reheating between every pass to minimize grain growth. All heating was done in a protective argon atmosphere. The slabs were hot-rolled to strips 50 mils thick. After hot rolling, all the material was pickled to remove the scale formed on the surface of the strip during hot rolling. The material was then cold-rolled to 12-mil strips. Single strips of the material used in this experiment were hydrogen-annealed at 1200°C for 16 hr in an alumina tube. Chemical analyses of strips M-1, M-3, M-4, M-7, and M-8 are given in Table I. Sulfur, silicon, and manganese analyses were made from the millings from the cold-rolled 12-mil strips. The oxygen analyses were made from slugs of the as-cast material. The hydrogen sulfide used in these experiments was supplied from cylinders containing a mixture of argon and 1 pet hydrogen sulfide. The parts per million of hydrogen sulfide were determined from the analysis of the exit gas of the annealing furnace during each anneal. The flow rate of hydrogen was approximately 1 liter per min in all anneals. The

Jan 1, 1964

By M. Dubrovsky, J. W. Evans

A laboratory scale cell (approximately 50 amps current) equipped with a fluidized bed cathode was used in a study of the electrodeposition of cobalt from acidified aqueous sulfate solutions The effect of current density (in the range 0.1 to 1 amp/cm2 of diaphragm), cobalt concentration (4 8 to 100 glliter) and catholyte pH (1 35 to 6 2) on current efficiency and energy consumption were determined. Generally the current efficiency increased with increasing current density and cobalt concentration Current efficiencies were comparable to those reported in the literature for conventional electrowinning

Jan 1, 1981

By Wm. Terry Siemers, Frank E. Kottlowski, George S. Austin

The value of industrial rocks and minerals produced in New Mexico in 1978 exceeded $227 million. The state ranked first in the nation in production of potash and perlite and was a leader in pumice production. Other commodities with sizable production in New Mexico include barite, caliche, clay, dimension stone, fuorspar, gypsum, humate, limestone, mica, salt, sand and gravel, scoria, and silica sand. Non-metallic resources are distributed throughout the state, but development and exploitation is concentrated in western and southeastern New Mexico. The value of industrial rocks and minerals within the state grew about 9% to more than $227 million in 1978. Continued growth, however, depends on continued demand, exploration, and development.

Jan 1, 1982

By M. K. Yen, W. R. Hibbard

Previous studies of plastic deformation of metals have emphasized the important role of bending and constraints during strain under relatively pure stresses.1"5 Some new phenomena such as early conjugate slip6 and polygonization7 are intimately concerned with the relief of bending stresses, the former by slip and the latter by a process analogous to re-crystallization. However, few analyses of the bending deformation of single crystals were found in the literature, and those8,9 are sufficiently previous to the modern interpretations of slip to invite further investigation in this area. The transverse bending mode of testing, using the two-point loading method, was selected because the center portion of the specimen may be considered as under a theoretically pure bending stress with a uniform bending moment. Considerable attention was given to both the lattice distortion and flow characteristics of the crystals during deformation. Experimental Proeedare A specimen under the action of equal and opposite couples at both ends is said to undergo pure bending. The shear and moment diagrams of a specimen under the two-point loading method of transverse bending are shown in Fig 1. The moment over the middle-third of the span is equal to PL/6, and the vertical shear is zero. Fig 2 (A) illustrates the stress distribution in the elastic range on a plane across the middle of the specimen. It can be seen that the normal stress has a maximum value at the extreme surfaces on the tension and compression sides, and decreases proportionately to zero as it approaches the neutral plane. However, when the plastic range is reached, the stress distribution is no longer a straight line relation, but changes in a manner which can be best illustrated as shown in Fig 2(B). The following calculation and stress analysis are mainly in accordance with the works reported by Timoshenkol0 and Kochendörfer.9 From the simple beam formula, the maximum normal stress will occur at the surface of the specimen. For a round specimen with a radius r and for a rectangular specimen with a height 2h and width 2b, the maximum normal stress, Sp, will be given by the following formulas: For round specimen: 2PL Sp = 3pr3 [1] For rectangular specimen: Sn = 8bh2 [2] Since it is reasonable to consider that slip takes place under the same conditions as in uniaxial loading, the resolved shear stress S?, along the operative slip direction will be as follows: For round specimen: 2PL sin x cos ? Sp = 3pr3 sin x cos ? [3] For rectangular specimen: PL S8 = 8bh2 sin x cos ? [4] where X is the angle between the specimen axis and the slip direction and X, the angle between the specimen axis and the major axis of the glide ellipse. It was also reported by Kochenclorfer9 that the critical bending moment, that is, the bending moment exerted on the specimen to initiate slip, should be higher than the value given by the equations stated above. Based

Jan 1, 1950

By D. S. Jacobus

It is proposed to give in this paper an estimate of the cost at which carburetted and uncarburetted water-gas will have to he sold, in order to compete successfully for steam-boiler use with anthracite coal. The following are analyses of the gas direct from the generator, and of the same after it has been carburetted for illuminating pnrposes. Per cent. by Volumes. I. 11. Uncarburetted. Carburetted. Nitrogen,.4.69 2.5 Carbonic acid,.3.47 .3 Ethylene,....... 0 12.5 Oxygen,....... 0 .2 Benzole vapor,...... 0 1.5 Carbonic oxide,.36.80 29.0 Marsh-gas,.2.16 24.0 Hydrogen,.52.88 30.0 100.00 100.0

Jan 1, 1889

By O. N. Carlson, E. D. Gibson, D. W. Bare

SEVERAL investigators have recently contributed to a clarification of the controversy concerning the allotropy of chromium. Ross and Hume-Rothery1 and Vasyutinskii et a1.2 have reported high-temperature X-ray data on unalloyed chromium from which they have concluded that no allotropic transformation occurs in this metal. Bechtoldt and vacher3 in their investigation of the Cr-Ni alloy system found no evidence for a transformation in chromium and Smart and Haynes4 in critically analyzing the data presented to date concerning this system could find no evidence for a eutectoid reaction in this system. Wyder and Hoch5 in research concurrent with our

Jan 1, 1964

By A. Yazan, M. Sagheer

To meet the demands of the planned development of Turkish steel industry an Iron ore processing plant is under construction at Divrigi, Anatolia and is planned to be commissioned mid of 1978. The plant has been designed for an annual capacity of 4 million tons of crushed magnetitic ore. About 1.9 million tons of coarse concentrate of 25-2 mm size and 1.3 million tons of pellet feed concentrate will be produced by wet screening, dry magnetic concentration of coarse size fractions and wet magnetic concentration of fine size fraction. The fine magnetic concentrate will be reground and filtered to prepare the feed for the pelletizing plant.

Jan 1, 1978

US 4,185,996 -- Removal of arsenic and sulfur Impurities from arsenic-containing cobalt sulfide ore. The ore is oxidized In air at a temperature of 700 to 800°C for 3 to 8 hr to drive off the bulk of the sulfur The oxidized ore 1s heated with a reducing gas at a temperature of 700 to 800°C for 2 to 6 hr to volatilize arsenic, and the final calcine 1s leached with an acid to eliminate substantially all of the remaining arsenic. A.R. Zambrano, assigned to Hanna Mining Co Jan. 29, 1980. 3 pp. (75-2). Filed. 2-13-78 (877,002).

Jan 1, 1982

By C. E. Birchenall, H. M. Schadel, G. Derge

EXISTING distribution data' for silicon between liquid iron and silver at steelmaking temperatures, 1500" to 1600°C, has made activity relationships in liquid silver-silicon alloys desirable as a method of determining the silicon activity in molten iron. To this end, through the use of radioactive Ag110 and the molecular beam technique described in a previous paper,' the vapor pressure of silver as a function of temperature has been measured over three silver-silicon alloys containing 3.9, 9.3, and 15.4 atomic pct (eutectic composition) silicon. The technique was that described for pure silver with the exception that a porcelain liner was used inside

Jan 1, 1951

By Leonard L. Melton, Calvin D. Saunders

The design and performance of many operations common to the petroleum industry depend upon the unique properties of a class of materials known as non-Newtonian fluids. The art of measuring and describing these properties, called rheology, has fallen far behind the field applica-tion of these fluids in this industry. Empirical methods are still employed although theoretically sound methods of analysis are now available. This paper illustrates a completely general method of analysis of the rheological properties of non-Newtonian fluids which id independent of the type of viscometer employed and also the rheological type of fluid encountered except those of a thixo-tropic or rheopectic nature. Values of the rheological properties of a fluid obtained using this method of analysis are based upon an absolute scale of measurement, eliminating the necessity of employ-jng arbitrary concepts of the flow properties of non-Newtonian fluids, The fundamental nature of this method of analysis is further demonstrated by evaluating the precision with which measurements have been made of these rheological properties by employing a dimensionless criteric: —the Fanning friction factor-Reynolds number correlation. INTRODUCTION Non-Newtonian fluids are not new in the petroleum industry. Particular properties of non-Newtonian materials have been recognized and used to advantage in drilling fluids and have found excellent application in the hydraulic fracturing process.'.' While usage of these fluids is not new in this industry, the art of measuring and describing their rheological properties is still in its infancy. This is reflected in the accepted method of evaluating drilling fluids, API RP 29, (1950), which recommends a one point "viscosity" measurement. These shortcomings are recognized by various groups in the industry and more adequate methods have been prposed.3,4 The efforts Of these people are to be commended; but, at the same time, the limitations of their method of analysis and viscometer must be appreciated. This method Of analysis is applicable Only to Bingham plastic fluids as is pointed out early in their articles. The consistency of a Bingham plastic fluid must also lie within the range of the viscometer which is also well defined by the author. It is believed that the apparent simplicity of this method of analysis and the utility Of Operation Of their viscometer will soon make the terms non-Newtonian fluid and Bingham plastic fluid synonymous as used in this industry; a tendency which has already been encountered. Application of this method of analysis to a non-Newtonian fluid other than a Bingham plastic can lead to erroneous results. The field of rheology has long been hampered by the adherence to arbitrary concepts of Of of the flow properties Of non-Newtonian fluids. This has resulted in the design and operation of viscometers so as to fulfill these concepts rather than following the more logical method of analyzing experimental data so as to yield a fundamental truth. completely Bingham proposed the concept Of plastic flow and yield asu rement. data presented by Buckingham could hardly be interpreted so as to substantiate this theory; but rather succeeded in establishing the fact that compliance with this flow concept could never be realized in the capillary tube vis-cometer.5 Bingham, in reply, sug-gested "Rather than complicate our formula, it would seem to me a much better plan to so change the conditions of flow that the formula will be linear... Reiner0 stated .This plan has been followed by me in collaboration with Miss Riwlin. . . . From the present paper (Reiner and Riwlin, 1929) it will be seen that it is possible to choose the conditions of flow so that the formula based on Bingham's law of plastic flow remains linear. This is realized in the rotation viscometer," Thus, a viscometer, with design and operation based on the Reiner and Riwlin equation for plastic flow, is restricted to a specific range of flow

Jan 1, 1958

By G. A. Reinhardt, H. J. Cutler

ThE Youngstown Sheet & Tube Co. has produced a large tonnage of 0.35 to 0.45 carbon forging steel, the acceptance of which was based on the physical properties of test specimens obtained by forging the original 5 3/4-in. (14.5 cm.) square bloom to a 3/4-in. (1.9 cm.) round. Annealed and tempered specimens were required. The test bars were annealed by heating from 900" to 950' C. and cooling slowly in mica. The test bars were tempered by heating to 825' to 875" C., quenching in water, and drawing to 515" to 535" C. Immediately after heat treatment, the test pieces were machined to a diameter of 0.534 in. (1.38 cm.) and tested. Very good physical properties were obtained and no difficulty was experienced in meeting the specifications called for. UlTimate Strength.. Elongation, Lb. pER Sq. In. PEE Cent.. in 4 In. Not LeEs Than Annealed specimens.............. 78,230 to 92,450. 18 Tempered...................... 120,000 to 149,350 9 After experience on this material, production of slightly higher carbon forging steel was started. The method of testing this material required that test blooms be either normalized or annealed. The normalizing consisted in heating to 850" to 900" C. and cooling in still air; the annealing, in heating to 850" to 900" C. and cooling in the furnace or in mica. From the treated bloom, the test pieces were taken either by core drilling or by sawing from points midway between the edges and the intersection of the diagonals. The cores or blocks were turned to a standard 2-in. test piece with a diameter of 0.564 in. and tested without further treatment. The physical requirements of the test pieces were: yield point, pounds per square inch minimum, 44,800; ultimate strength, pounds per square inch, 89,600 to 112,000; elongation, per cent. in 2 in. not less than 17. Difficulty was encountered as soon as work on this material was started. Many precautions and refinements were instituted but it was found very difficult to secure the required elongation.

Jan 1, 1920

By Charles L. Harness

STRONTIUM is an essential constituent of celestite (strontium sulphate), of the rarer strontianite (strontium carbonate), and of a few very rare minerals. Celestite is the chief ore but strontianite is more valued except for making the purest strontium salts, because of its ease of processing. The public knows strontium mainly as the source of the red flame in fireworks but it has many other uses. PROPERTIES The celestite of commerce is a massive mineral of varying texture: coarsely crystalline, fibrous, bladed, very fine grained or earthy. The color varies greatly with the nature of the impurities but the purer specimens are light blue (Latin, caelum, sky) or white. The strontianite of commerce is a massive mineral, more or less coarsely crystalline. The color varies with the impurities. Distinctive characteristics are effervescence with acids, density (3.68 to 3.71), and crimson strontium flame. A typical British celestite before World War II analyzed: SrSO4, 96.55 pct; SrCO3, 0.17; BaSO4, 0.25; CaSO4, 0.54; MgCO3, 0.15; R20,, 0.90; Si02, 1.38.10 A German strontianite analyzed: SrCO3, 90.9 pct; CaCO3, 7.5; BaCO3, 0.1; Fe2O3, 0.05; A1203, 0.1; SiO2, 0.04; S, 0.1; P, 0.005.10 ORIGIN AND MODE OF OCCURRENCE According to Clarke,9 strontia forms about 0.02 pct of the crust of the earth and is present in most igneous rocks, but in smaller quantities than barium. Under certain conditions, large masses of celestite are deposited from sea water with anhydrite. The presence of large amounts of celestite in some saline deposits and its absence in others suggests that the deposition of celestite depends on whether certain as yet undetermined concentrations of sulphate and chloride ions are reached in the brines. The most extensive of these sedimentary deposits are those of the Keuper (Triassic) in England, of the Zechstein (Permian) in Germany, and of various Cretaceous formations in Texas, Arkansas, and Utah. Of the deposits of southeastern California and western Arizona,

Jan 1, 1949

By C. O. Burgess, A. B. Kinzel

Although vanadium is an important constituent of almost every brand of high-speed steel manufactured today, little is known as to its role in this series of alloys. The now standard 18 per cent tungsten and 4 per cent chromium constituents were the result of developments and improvements before 1903. In that year, vanadium was added to the steel by Dr. J. A. Mathews. This proved to be an outstanding contribution, so that the standard high-speed steel of today is generally referred to as the 18-4-1 type—18 per cent W, 4 per cent Cr and 1 per cent V. Various modifications have been attempted since then, but with the exception of the introduction of cobalt, no striking improvements have occurred. Vanadium has been increased to 2 per cent in many of the common brands, and at least one brand contains 5 per cent V in addition to the usual tungsten and chromium. The carbon has been gradually increased so that it is not uncommon to find 0.80 per cent in the standard grade, although the carbon in the 5 per cent vanadium steel mentioned above is approximately 1 per cent, and even 1.2 per cent has been made experimentally. The role of vanadium has never been well understood, and although vanadium has been increased to 2.5 and even 5 per cent in certain high speed steels, it has not been generally established that the higher vanadium contents result in superior cutting properties. However, in all of the investigations, of which the writers are aware, the interrelation of the vanadium and carbon contents was not considered as a prime factor. The carbon content was held at 1.2 per cent or less—generally at the usual 0.65 to 0.75 per cent. Theoretical Aspects Although the role of vanadium is not understood, there are theoretical considerations which indicate definite reasons for the improved cutting effciency due to vanadium. Refinement of the secondary grain is one distinct possibility. The well-known action of vanadium in limiting grain size might well be expected to operate in high-speed steels, and even though its action were not evident in the parent austenite grain.

Jan 1, 1932