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By R. W. Raymond

CLARENCE King born January 6,1842, at Newport, R. I. His ancestors on both sides mere New Englanders, of English blood, and among them not a few distinguished themselves in art, science, politics or commerce. His grandfather, Samuel Vernon King (partner in 1803 in the house of Talbot, O1yphant & King, later known as King $ Co.), was a pioneer in the China trade, and four of his sons succeeded him in the business. Three of the four died in the far East; and one of

Jan 1, 1903

Abbott, Franklin E. Adgate, Frank Aertsen, G. Aid, Kenneth Albert, H. I. Alexander, D. B. W. Allan, Wm. G. Allen, R. 0. Allen, Roy H. Aller, Mr. and Mrs. F. D. Altmayer, Maurice Ambler, Harry A. Ambrose, A. WV. Ammon, Mark A. Ammon, Mr. and Mrs. Robt. Anderson, George H. Anderson, Mr. and Mrs. L. D. Andros, S. 0. Appleby, W. R. Archer, R. S. Armitage, Paul Arobb, Alden D. Arthur, Walter Ashman, A. 0. Atkinson, R. H. Aupperle, J. A. Austin, D. F. Avery, G. E.

Jan 11, 1919

By U. K. Custred, E. W. Long, V. R. Degner

In 1973, the United States production of marketable phosphate rock set a record in excess of 42 million tons. This production rate is expected to continue to increase, due to the growing international requirement for fertilizer, at a rate exceeding 5% per year well into 1977. One approach towards increasing plant production capacity to meet the growing demand is through large-capacity flotation cells, provided they achieve metallurgical performance comparable to existing smaller cells. A 9-month evaluation test program recently completed at the Haynsworth mine at Bradley, Fla., demonstrated the feasibility of achieving economically acceptable concentrate grade and recovery levels using large, high-capacity flotation cells. The composition of the feed to the Haynsworth beneficiation plant is a typical Florida pebble phosphate matrix composed of phosphorite pebbles ranging in size from approximately 1-1/2 in. down to 150 mesh and intimately associated with a mixture of clay and sand (essentially silica). The feed contains approximately 22 to 28% phosphate reporting as tricalcium phosphate, Ca3 (PO,) 2, or "bone phosphate of lime" (BPL). The flotation section utilizes the double-float procedure typical of Florida plants. The phosphate is first floated away from the silica in the rougher circuit, using crude fatty acid, ammonia, and fuel oil or kerosene. Rougher conditioning is accomplished at 60 to 70% pulp solids with sufficient ammonia added to raise the pH to 9 to 9.5. Following coarse and fine rougher flotation, the concentrate (overflow) streams are joined and conditioned (sulfuric acid cleaned and washed) prior to entering the cleaner circuit where an amine float (cationic reagent and kerosene added in the feed box; pH 7.3 to 7.8) is employed to float the silica. The feed to the coarse rougher circuit averages 29% +35 mesh while the fine rougher feed averages 10%+35 mesh. Primary attention was directed toward the large rougher cell performance (recovery and grade) on coarse feed during the Haynsworth evaluation program. Flotation Cell Test Program A row of three No. 120 size (300 cu ft) WEMCO flotation cells was installed in parallel with an existing air-cell row. The total installed volume of the large cell circuit was 900 cu ft and required a floor space of 306 sq ft. This compared to the air-cell total volume of 200 cu ft and 152 sq ft floor space. (Both floor areas include feed and tails hoppers but exclude walkways.) Fig. 1 is a schematic cross section of the large flotation cell showing the relative location of key mechanism elements. In operation, the rotor generates a fluid vortex extending up along the walls of the standpipe and creating a sufficient vacuum within its core to ingest air into the standpipe/rotor cavity through the air inlet duct. The ingested air mixes with the pulp, which has been recirculated through the false bottom and draft tube, in the rotor. Further mixing occurs as the air and pulp move radially outward from the rotor, finally passing through the disperser into the flotation cell. Flotation is accomplished outside the disperser, where phosphorite laden air bubbles rise and the remaining pulp recirculates down along the cell wall to the false bottom and draft tube. Large-flotation-cell performance is influenced by the ability of the mechanism to (1) circulate, or suspend, the solids in the pulp; (2) ingest air into the rotor cavity; and (3) mix the air and pulp effectively. The proper balance between pulp circulation and air ingestion is a key consideration in achieving good recovery in a course feed application. Large-flotation-cell pulp circulation and air transfer characteristics are significantly influenced by rotor speed and rotor submergence; therefore, these two operational parameters can be used to "optimize" a particular mill application. Fig. 2 maps the hydraulic performance of the WEMCO No. 120 size flotation cell. This map can be used to relate the cell operational parameters which influence metallurgical performance. At a given rotor speed, power intensity (i.e., pulp circulation) is seen to increase, and airflow decrease, as rotor submergence is increased. The inverse relation between power and airflow is due to the two-phase air-liquid mixture density reduction accompanying the increased airflow rate. For any fixed rotor submergence, the power intensity (i.e., fluid circulation) and airflow both increase as rotor speed is increased. The selection of these two mutually related operating conditions (i.e., rotor speed and submergence) was a key consideration in the Haynsworth evaluation program.

Jan 1, 1976

By H. A. Wheeler

It may surprise some of our members to learn, that, among the industries based on the mineral resources of the United . States, clay now ranks third, being exceeded in value of product only by pig-iron and coal. The present annual value of clay-products exceeds the value of the outputs of gold or silver, and also exceeds the combined values of copper, leacl, zinc, aluminum, mercury, antimony and nickel. These facts are shown in Table I. which gives the statistics for the year 1902 :

Jan 1, 1905

By G. R. Leverant, C. P. Sullivan

Re crystallized TD-nickel mi-2Th0,) in both coated und uncoated conditions was fatigued at 1800°F at total strain ranges varying .from 0.2 to 0.75 pct. The fatigue life of uncoated inaferal, Nf, was related to the total strain range, ?eT, by (2Nf/021AeT = 0.014. A duplex Al-Cr pack coating increased the fatigue life by about a factor of two. The cracks that led to failure in both coated and uncoated material were initiated at the outer surface, indicating that the mechanical properties of the surface layers were important in determining fatigue life. Crack propagation and subsurface crack initiation in the TD-nickel occurred preferentially at grain boundaries with cavitation at thoria particle-matrix interfaces an integral part of the grain boundary fracture process. The importance of both the grain morphology developed during thermome chanical processing of TD-nickel and the distribution of thoria particle sizes to fatigue resistance are discussed. THE fatigue properties of only a few dispersion-strengthened metals have been studied at temperatures 0.5 Tm;1,2 among these have been lead and aluminum containing oxide dispersions. TD-nickel is a material of interest for application in aircraft gas turbine engines, but little fundamental information is available on its behavior under cyclic loading conditions. In this study, the low-cycle fatigue properties of TD-nickel were determined at 1800°F with emphasis on the 101-lowing; 1) the relation of the grain morphology produced during thermomechanical processing to crack initiation and propagation; 2) the role of thoria parti-cles in the fracture process; and 3) the effect of an oxidation resistant coating on fatigue life. I) MATERIAL AND EXPERIMENTAL PROCEDURE The TD-nickel was supplied by DuPont as a 5/8-in. thick plate which had been subjected to a proprietary series of thermomechanical treatments with a final anneal at 2000°F for 1 hr in hydrogen. The composition of the material is given in Table I. At the test temperature of 1800°F, the 0.2 pct offset yield stress was 15,000 psi, and the elongation and reduction in area were 4.6 and 3.0 pct, respectively. The microstructure of this material has been previously described.&apos; Briefly, it consists of an array of lath-shaped grains, about 0.15 mm in thickness, with the long dimension of each grain parallel to the primary working direction, Fig. 1(a). The presence of very small annealing twirls, Fig. l(b ), together with the absence of extensive dislocation networks, Fig. L/C), indicated that the material was in the recrystal- Table I. Composition of TD-Nickel ThO2 2.3 vol pct C 0.0073 wt pct lex 0.01 wt pct Cr 0.01 wt pct Cu 0.004 wt pct S 0.001 wt pct Ti <0.001 wt pct Co <0.01 wt pct Ni bal lized condition. Commercial TD-nickel sheet has a similar grain size and shape, but unlike the present material is not recrystallized as evidenced by the absence of annealing twins and the presence of a well-developed dislocation substructure.4 The plate material had Young&apos;s moduli in the rolling direction of 22 x 106 psi and 13 x 106 psi at room temperature and 1800°F, respectively, indicating a texture with a strong {100}<001> component in agreement with previous observations on recrystallized TD-nickel sheet.596 The 2.3 vol pct of thoria particles were uniformly distributed although some clustering and stringering of larger particles was occasionally seen. The average diameter of the particles was 450 and the calculated mean planar center-to-center spacing was 2100Å. Two specimens were coated with a duplex A1-Cr pack coating. The coating was somewhat nonuniform from one position to another along the gage length. An area of the coating after testing is shown in Fig. 2. Electron microprobe analysis revealed the following zones in the various lettered regions indicated in Fig. 2: A) a bcc matrix of B-NiA1 with some chromium in solid solution along with a fine dispersion of a chromium-rich second phase which was probably precipitated during cooling from the test temperature to room temperature; B) fcc y&apos;-Ni,Al with some chromium in solid solution; C) porosity; D) a two-phase mixture of a chromium-rich solid solution containing nickel and aluminum and a small volume fraction of a nickel-rich solid solution having approximately the same composition as the immediately adjacent portion of region E, E) the TD-nickel substrate containing chromium in solid solution to a depth of 5 to 10 mils. As expected from the nature of the diffusion processes involved,7 the thoria particles were present only up to the layer of porosity, region C, Fig. 2. The measured thickness of the coating proper, zones A to D, after testing was 1 to 2 mils. The specimen design and testing techniques have been previously discussed.&apos; Stressing was axial and parallel to the lath-shaped grains (i.e., parallel to the rolling direction). The total strain range was controlled between zero and a maximum tensile strain varying from 0.2 to 0.75 pct. (The test at 0.2 pct total strain range was switched to load control at 1030 cycles at which point the peak tensile and compres-

Jan 1, 1970

Elected Died 1882 *ABBOTT, ARTHUR V 1906 1903 * ADAMS, CHARLES C. 1905 1884 *ADDY, MATTHEW 1896 1894 *ALLFN R B 1896 1874 *AMIOT, H 1892 1886 *AMSLER, CARL 1894 1895 *ÅNGSTROM, CARL 1901 1895 *ARMSTRONG, JOHN F 1898 1882 *ARNOLDS, HUGO 1886 1875 *ASHBURNER, CHARLES A 1889 1872 *ASIIBURNER, WILLIAM 1887 1883 *ATKINS, C M , JR 1885 1897 *AYERS, WILLIAM 1898 1885 *BABCOCK, GEO H 1893 1884 *BAILEY, EDWARD 1889 1880 *BAILEY, JACKSON 1887 1900 *BALLOU, FRANKLIN 1903 1886 *BARNES, F W 1892

Jan 1, 1910

By M. J. Marcinkowski, E. N. Hopkins

An investigation has been made of the ß(fcc) — a(hexagonal) transformation which occurs in lanthanum using both electrical resistivity and transmission electron microscopy techniques. It has been shown that the ß phase can be retained below the transformation temperature by rapid quenching but that the sample immediately begins to transform to the a phase. The transformation is observed to nucleate in the vicinity of inclusions. Based on the above observations, a detailed model of the transformation has been advanced which involves the nucleation of an extrinsic stacking fault bounded by a pair of Shockley partial dislocations in the vicinity of some heterogeneity, i.e., an inclusion. The stress field of the resultant dislocation pair acts to nucleate extrinsic faults in adjacent planes and leads quite naturally to the B-a conversion with a minimum of strain energy induced in the crystal. LANTHANUM possesses an fcc structure ß) (8) upon cooling transforms to a hexagonal modification (a) in much the same way as cobalt. The one exception, however, is that the stacking sequence of the closest packed planes in a La is ABAC ABAC, and so forth,1 whereas in cobalt it is ABAB, and so forth, i.e., hep. Mainly on the basis of transmission electron microscopy techniques, there seems to be little doubt that the 0 — a transformation in cobalt involves a dislocation mechanism2 although its exact nature still remains obscure. Although the ß - a transformation in lanthanum is somewhat more complex than that occurring in cobalt, it was thought that its very uniqueness would be helpful in understanding fcc — hexagonal transformations in general. Such a general understanding of these transformations is important since they represent what are perhaps the simplest of the martensitic class of transformations. The experimental techniques used were those of electrical resistivity and transmission electron microscopy. EXPERIMENTAL PROCEDURE The lanthanum used in this investigation was prepared by the calcium reduction of lanthanum fluoride in a tantalum crucible under an argon atmosphere as described by Spedding et al. The residual calcium was removed by vacuum remelting in a tantalum container. Portions of the metal were then analyzed by emission spectroscopy as well as vacuum fusion. The amounts of the various impurities that were found are listed in Table I. A portion of the lanthanum ingot was swaged at room temperature into 0.030-in.-diam rod for the resistivity samples while the remainder was rolled into 0.010-in.-thick sheet for the transmission electron microscopy phase of this investigation. In order to eliminate the plastic deformation induced in the samples during fabrication, they were sealed in evacuated tantalum lined quartz capsules and annealed for 1 hr at 700° C. Specimen resistances were measured using the conventional "four-wire" technique described by MacDonald, 4 employing a type K-3 Universal Potentiometer and a standard 0.001-ohm resistor, both manufactured by Leeds and Northrup Co. By taking into account all of the possible errors in the apparatus, it was felt that the absolute resistivities of the approximately 0.87-in.-long specimens measured are reliable to 3 pct. Resistances from room temperature to 700°C were measured using a vacuum furnace. In order to avoid sample contamination by the thermocouple, chromel-alumel leads were spot-welded into a tantalum shield which in turn was welded to the lanthanum specimen. Resistances below room temperature were obtained by transferring the sample to a helium gas-filled quench tube and slowly dripping liquid nitrogen into a surrounding dewar flask. A steady reduction of temperature to about —190°C was completed in about 23 hr, and the resistances were measured at various temperature intervals. As will be shown shortly, rapid quenching from above about 350°C was sufficient to suppress the B -a transformation initially but subsequent annealing at lower temperatures leads to a partial ß --a conversion. To investigate this aspect of the transformation, the samples were suspended in the hot zone of a helium-filled furnace from which they could be rapidly dropped into the quench tube mentioned previously which was now

Jan 1, 1969

Frank 11. Probert, Neudorf, Anhalt, Germany (communication to the Secretary): I have read with much pleasure Mr. Collier&apos;s valuable paper. But the system of timbering which he describes as used in the levels, stopes, etc., though it must be admitted to be very strong and safe, seems to me somewhat extravagant. The amount of timber required every month for such a system must be enormous; and only where suitable material could be cheaply obtained would such a plan be economically practicable. The first point which strikes me is the unusually great diameter of the timber employed. In the mines of Pfaffenberg and Meiseberg, which are under my supervision, the country-rock consists of argillaceous slates, traversed by innumerable small fissures or joints, dipping at all angles and striking to all points of the compass. Undoubtedly, this net-work has been caused by the upheaval of granite masses in the vicinity. Each fissure is accompanied by a more or less well-c1efinc.d gouge or fluccan, caused by the rubbing together of the slates at or after the original disturbance. In such

Jan 1, 1900

By F. J. Haller

IN 1943, we found, in the new Mather operation, a very unusual and disappointing condition in the footwall rock where all of our main haulageways were to be located. With the exception of a few hundred feet out of the thousands then planned and since driven, all of the openings require support. In general, the ground is not particularly heavy, at least by our standards, but it must be supported and the back carefully covered. Also, our operations require rather wide plat openings (16 to 18 ft) and rather flat curves at the turn-outs, all of which adds to the problem. When this completely unforeseen condition was discovered, ordinary timbering was the only answer, because of the impossibility of obtaining adequate steel supplies in time due to war shortages. Then by the time steel supplies were obtained and a practice developed, we found ourselves with between four and five miles of main haulage drifts and plat openings of a permanent nature, all of which were supported by hardwood timber, some of which had already rotted to an unsafe degree. Also, our drifting program was adding some two miles per year to the above figure. F. J. HALLER, Member AIME, is Superintendent, Mather Mine, Cleveland-Cliffs Iron Co., Ishpeming, Mich. AIME Columbus Meeting, September 1949. TP 2840 A. Discussion (2 copies) may be sent to Transactions AIME before May 31, 1950. Manuscript received Aug. 22, 1949. Revision received Jan. 17, 1950. To give all of the details of our experiments, studies, and experiences would fill a large book, but we were satisfied that our organization had done an excellent job, starting from scratch. You can appreciate our surprise when we discovered that we had added very little to an existing record. Attention was called to a footnote in a copy of "Carnegie Pocket Companion" year 1923. The note read: "Full information as to uses of H-Beams is given in pamphlet entitled &apos;Steel Mine Timbers.&apos; " A search of our Engineering Library brought to light a pamphlet printed in 1911 showing extensive use of steel for this purpose. Except for welding in place of riveting, we have added very little to the designs in that book. We have, however, developed an experience which proves, at least to our own satisfaction, that steel mine supports pay off under the proper conditions. We are now convinced, in spite of the relatively high initial cost of materials, that steel sets, because of comparatively low installation cost, are actually cheaper than either treated or untreated wood sets, if they are properly designed and adapted. Several Sections in Use: Convenience guided our first experiments in steel sets, since for a number of years, we had used the 4-in. WF, 10 lb per ft section in 10-ft lengths as safety forepoles along with wood forepoles. This section replaced the 40-lb rail which had formerly been used for the purpose. Having the 4-in. WF sections on hand, it was natural that our first experiments in steel sets involved their use. Later, the rolling of the 10-lb section was discontinued in favor of the much stronger 13-lb section, which is now standard for both legs and caps in areas of no particular weight, but which, none the less, require permanent support. Our experiments involved the use of the 10- and 13-lb sections as legs and 6- and 8-in. I beams, 16 and 23 lb per ft, respectively, as caps. Experience soon indicated that, if the ground were heavy enough, and the opening wide enough to require a cap stronger than 13-lb, the 8-in, 23-lb should be used, eliminating the 6-in. I beam. We now know that the 8-in. WF section of the same weight, which we propose to use in the future, is considerably stronger for the amount of money involved. Comparative Strengths: Tables I to IV giving strengths of several species of timbers as compared with the structural sections that we now use have been prepared in accordance with accepted practice. Experience indicates that failure due to compression perpendicular to the grain of the wood does not destroy the effectiveness of a wood set frequently enough to be a practical factor. Therefore, no table of these values is included.

Jan 1, 1951

By F. J. Haller

IN 1943, we found, in the new Mather operation, a very unusual and disappointing condition in the footwall rock where all of our main haulageways were to be located. With the exception of a few hundred feet out of the thousands then planned and since driven, all of the openings require support. In general, the ground is not particularly heavy, at least by our standards, but it must be supported and the back carefully covered. Also, our operations require rather wide plat openings (16 to 18 ft) and rather flat curves at the turn-outs, all of which adds to the problem. When this completely unforeseen condition was discovered, ordinary timbering was the only answer, because of the impossibility of obtaining adequate steel supplies in time due to war shortages. Then by the time steel supplies were obtained and a practice developed, we found ourselves with between four and five miles of main haulage drifts and plat openings of a permanent nature, all of which were supported by hardwood timber, some of which had already rotted to an unsafe degree. Also, our drifting program was adding some two miles per year to the above figure. F. J. HALLER, Member AIME, is Superintendent, Mather Mine, Cleveland-Cliffs Iron Co., Ishpeming, Mich. AIME Columbus Meeting, September 1949. TP 2840 A. Discussion (2 copies) may be sent to Transactions AIME before May 31, 1950. Manuscript received Aug. 22, 1949. Revision received Jan. 17, 1950. To give all of the details of our experiments, studies, and experiences would fill a large book, but we were satisfied that our organization had done an excellent job, starting from scratch. You can appreciate our surprise when we discovered that we had added very little to an existing record. Attention was called to a footnote in a copy of "Carnegie Pocket Companion" year 1923. The note read: "Full information as to uses of H-Beams is given in pamphlet entitled &apos;Steel Mine Timbers.&apos; " A search of our Engineering Library brought to light a pamphlet printed in 1911 showing extensive use of steel for this purpose. Except for welding in place of riveting, we have added very little to the designs in that book. We have, however, developed an experience which proves, at least to our own satisfaction, that steel mine supports pay off under the proper conditions. We are now convinced, in spite of the relatively high initial cost of materials, that steel sets, because of comparatively low installation cost, are actually cheaper than either treated or untreated wood sets, if they are properly designed and adapted. Several Sections in Use: Convenience guided our first experiments in steel sets, since for a number of years, we had used the 4-in. WF, 10 lb per ft section in 10-ft lengths as safety forepoles along with wood forepoles. This section replaced the 40-lb rail which had formerly been used for the purpose. Having the 4-in. WF sections on hand, it was natural that our first experiments in steel sets involved their use. Later, the rolling of the 10-lb section was discontinued in favor of the much stronger 13-lb section, which is now standard for both legs and caps in areas of no particular weight, but which, none the less, require permanent support. Our experiments involved the use of the 10- and 13-lb sections as legs and 6- and 8-in. I beams, 16 and 23 lb per ft, respectively, as caps. Experience soon indicated that, if the ground were heavy enough, and the opening wide enough to require a cap stronger than 13-lb, the 8-in, 23-lb should be used, eliminating the 6-in. I beam. We now know that the 8-in. WF section of the same weight, which we propose to use in the future, is considerably stronger for the amount of money involved. Comparative Strengths: Tables I to IV giving strengths of several species of timbers as compared with the structural sections that we now use have been prepared in accordance with accepted practice. Experience indicates that failure due to compression perpendicular to the grain of the wood does not destroy the effectiveness of a wood set frequently enough to be a practical factor. Therefore, no table of these values is included.

Jan 1, 1951

By H. W. Turner

THE axis of the middle portion of the Ural mountains is made up chiefly of highly compressed igneous and sedimentary schists, considered of Devonian age by the Russian geologists, with large areas of serpentine (peridotite originally) gabbro, etc., intrusive in the schist series. In addition there are large areas of probably older granitic and gneissic .rocks. The nickel deposits referred to in this paper are found in the Devonian schists and their associated igneous rocks. The gabbro-peridotite intrusions probably took place in late Devonian or early Permian time, inasmuch as the Permian and Carboniferous beds lie at gentle angles on the Devonian series on the west slope of the Urals. Perhaps the first attempt to work a nickel deposit in the Urals was made about 1866 in the Revdinsk district, which is situated southwest of Ekaterinburg. I was informed by a Russian that a wet method of extracting the nickel was tried but was not a commercial success. This deposit has been described by Müller,1 Foullon,2 and Karpinski.3 Beck4 gives an abstract of these papers.

Jan 2, 1914

By F. C. Muttitt

The physical arrangement of the continuous casting facilities at Algoma have been described a number of times in previous papers. For the purposes of this discussion, it is sufficient to state that the casting plant is located at a considerable distance from the basic oxygen shop which supplies it, involving a relatively lengthy ladle transfer movement. (Fig. I) The handling of the ladle by two separate cranes, first to the argon station, and thence to the casting machines, results in an average interval, from start tap to start cast, of 45 minutes. The effects of such extended retention time on temperature control and on refractory performance are well known. Tapping temperatures well above normal are necessary to insure that the ensuing heat losses do not result in an undue incidence of premature tundish freeze-offs. The heat lost, as well as being a function of the retention time, becomes more critical with smaller ladle size; winter temperatures add to the problem with their effect in chilling ladles and increasing radiant losses.

Jan 1, 1972

By L. F. Mondolfo

R301 is a clad aluminum alloy, composed of a core of a duralumin-type alloy clad with a magnesium silicide alloy. It differs from other well-known clad alloys in that the cladding and the core respond to the same heat-treatments. and therefore the cladding contributes appreciably to the mechanical properties of the material. In Table I are reported the compositions of the core and cladding alloy for the material used for the experiments. Table i.—Chemical composition of R~OI Used for the Experiments Element Core Cladding Cu........................ . 0.01 Fe......................... . 0.42 Si......................... 0. 0.71 Mg........................ . 0.99 Mn ........................ . 0.54 In clad aluminum alloys where the core contains copper and the cladding does not, at elevated temperatures the copper tends to diffuse from the core through the cladding. This fact is well known and many investigations have been conducted to determine the features of this diffusion. Most of those investigations cover materials clad with pure aluminum; the present investigation covers a material clad with an alloy. Since the cladding thickness on R~OI varies with the gauge, as shown in Table 2, several gauges were investigated. Material and Procedure he material used was sheet of the following gauges: o.o2~, 0.040, 0.064, 0.102, 0.170 Cut in pieces approximately 3 by 5 in., it was in the cold-rolled state and was soaked for increasing times at the following temperatures: glo°F., 940°F., 970°F. A Lindberg cyclone furnace was used for the experiments. The procedure was as follows: The furnace was started empty with controlling pyrometer set at the determined temperature. After the furnace had reached that temperature, it was run for some 20 to 30 min. empty, in order to allow the temperature inside to become stabilized. Then the first samples were introduced. A load thermocouple, with recording pyrometer, was connected with the sample of the heaviest gauge. About 10 min. was required for the material to reach temperature and the soaking time was counted from that point. After zoo min. soaking, the second group of samples was introduced without stopping the furnace. After 200 min. more, the third group of samples was introduced, and so on, until the last sample had been introduced. Every time the furnace was opened and new samples were added, a drop of temperature was registered by the thermocouple connected with the material

Jan 1, 1946

By L. F. Mondolfo

R301 is a clad aluminum alloy, composed of a core of a duralumin-type alloy clad with a magnesium silicide alloy. It differs from other well-known clad alloys in that the cladding and the core respond to the same heat-treatments. and therefore the cladding contributes appreciably to the mechanical properties of the material. In Table I are reported the compositions of the core and cladding alloy for the material used for the experiments. Table i.—Chemical composition of R~OI Used for the Experiments Element Core Cladding Cu........................ . 0.01 Fe......................... . 0.42 Si......................... 0. 0.71 Mg........................ . 0.99 Mn ........................ . 0.54 In clad aluminum alloys where the core contains copper and the cladding does not, at elevated temperatures the copper tends to diffuse from the core through the cladding. This fact is well known and many investigations have been conducted to determine the features of this diffusion. Most of those investigations cover materials clad with pure aluminum; the present investigation covers a material clad with an alloy. Since the cladding thickness on R~OI varies with the gauge, as shown in Table 2, several gauges were investigated. Material and Procedure he material used was sheet of the following gauges: o.o2~, 0.040, 0.064, 0.102, 0.170 Cut in pieces approximately 3 by 5 in., it was in the cold-rolled state and was soaked for increasing times at the following temperatures: glo°F., 940°F., 970°F. A Lindberg cyclone furnace was used for the experiments. The procedure was as follows: The furnace was started empty with controlling pyrometer set at the determined temperature. After the furnace had reached that temperature, it was run for some 20 to 30 min. empty, in order to allow the temperature inside to become stabilized. Then the first samples were introduced. A load thermocouple, with recording pyrometer, was connected with the sample of the heaviest gauge. About 10 min. was required for the material to reach temperature and the soaking time was counted from that point. After zoo min. soaking, the second group of samples was introduced without stopping the furnace. After 200 min. more, the third group of samples was introduced, and so on, until the last sample had been introduced. Every time the furnace was opened and new samples were added, a drop of temperature was registered by the thermocouple connected with the material

Jan 1, 1946

By B. D. Cullity

Gold and beryllium form an intermediate phase composed of the two metals in equal atomic proportions and having the formula AuBe. According to Winkler,&apos; this phase probably exists in two modifications: beta, stable below about 600°C, and alpha, stable between 600°C and the melting point, about 740°C. Only the low-temperature beta form will be considered in this paper. Experimental Procedure The gold used had a fineness of 999.75 to 999.85, balance mainly silver, and the beryllium purity was better than 99.8 pct. AuBe was prepared by melting the constituents in a beryllia crucible in an evacuated induction furnace. After melting and thorough mixing, the alloy was allowed to solidify in the crucible. No difficulty was encountered in obtaining a homogeneous ingot. Both chemical analysis and microscopic examination of the ingot showed that the alloy was essentially one phase, containing 50 at. pct gold. The alloy was quite brittle and powder samples could easily be prepared by grinding in an agate mortar. The X-ray diffraction patterns were made with CuK-alpha radiation in a Debye-Scherrer powder camera 57.3 mm in diameter. The film was placed unsym-metrically in the camera in order to afford a basis for film-shrinkage corrections. A sample homogenized at 500°C gave the same diffraction pattern as a sample taken from the as-melted ingot. General Results The diffraction pattern of AuBe was readily indexed on the basis of a simple cubic lattice with ao = 4.659 + 0.001kX. If the unit cell is assumed to contain four AuBe "molecules," the calculated X-ray density is 13.46 grams per cc as compared with the measured density of 13.55 gm per cc. The only missing reflections in the diffraction pattern are (100) and (220) (see Table I). Since these missing reflections are not those characteristic of body or face centering, the lattice of AuBe must be simple cubic. To locate the positions of the atoms within the unit cell, two possibilities had to be considered: I. The structure was disordered and there were eight positions to be filled by an LCaverage" gold-beryllium atom. That the structure was disordered seemed unlikely since the lattice parameter did not vary with composition in alloys containing sornewhat more and somewhat less than so at&apos; pet gold, indicating a fixed composition for AuBe.

Jan 1, 1947

By B. D. Cullity

Gold and beryllium form an intermediate phase composed of the two metals in equal atomic proportions and having the formula AuBe. According to Winkler,&apos; this phase probably exists in two modifications: beta, stable below about 600°C, and alpha, stable between 600°C and the melting point, about 740°C. Only the low-temperature beta form will be considered in this paper. Experimental Procedure The gold used had a fineness of 999.75 to 999.85, balance mainly silver, and the beryllium purity was better than 99.8 pct. AuBe was prepared by melting the constituents in a beryllia crucible in an evacuated induction furnace. After melting and thorough mixing, the alloy was allowed to solidify in the crucible. No difficulty was encountered in obtaining a homogeneous ingot. Both chemical analysis and microscopic examination of the ingot showed that the alloy was essentially one phase, containing 50 at. pct gold. The alloy was quite brittle and powder samples could easily be prepared by grinding in an agate mortar. The X-ray diffraction patterns were made with CuK-alpha radiation in a Debye-Scherrer powder camera 57.3 mm in diameter. The film was placed unsym-metrically in the camera in order to afford a basis for film-shrinkage corrections. A sample homogenized at 500°C gave the same diffraction pattern as a sample taken from the as-melted ingot. General Results The diffraction pattern of AuBe was readily indexed on the basis of a simple cubic lattice with ao = 4.659 + 0.001kX. If the unit cell is assumed to contain four AuBe "molecules," the calculated X-ray density is 13.46 grams per cc as compared with the measured density of 13.55 gm per cc. The only missing reflections in the diffraction pattern are (100) and (220) (see Table I). Since these missing reflections are not those characteristic of body or face centering, the lattice of AuBe must be simple cubic. To locate the positions of the atoms within the unit cell, two possibilities had to be considered: I. The structure was disordered and there were eight positions to be filled by an LCaverage" gold-beryllium atom. That the structure was disordered seemed unlikely since the lattice parameter did not vary with composition in alloys containing sornewhat more and somewhat less than so at&apos; pet gold, indicating a fixed composition for AuBe.

Jan 1, 1947

FOLLOWING the passage of resolutions by a num-ber of the western local sections, which have beer printed in previous issues, the Board of Directors appointed a committee consisting of Messrs. Reynders, DeGolyer, Taylor and Merica, to call on the Director of the Budget, and to bring these resolutions to his attention. In response to a request to the committee Mr. Reynders has addressed the following letter to General Lord. In response to a suggestion made in the course of the conference held between you and President DeGolyer of this Institute at Washington on Oct. 6, I present herewith a brief statement of the reasons that have led the mining engineers and metallurgists of this country to urge upon the Government a policy of increasing support from year to year to the United States Geological Survey and the Bureau of Mines. While these are not the only technical bureaus to which we look for data and guidance in our work of winning and rendering useful the mineral re-sources of the country, they are the ones on which we chiefly rely and the usefulness of which extends over all the industries which are based on mines and mining. In calling this matter to your attention and to that of the departments in which these bureaus are situated, I am acting on behalf of a special committee appointed by the Board of Directors and which includes men in close and intimate contact with the iron, coal, petroleum, metals and metallurgical industries; men well qualified by experience and position to voice the real feeling of these industries. The subject is not a new one to our Board, which has long kept a watchful eye on the work of the two bureaus as would be natural in that the American Institute of Mining Engineers, represents the largest group of technical men and executives and the one of most wide-spread interest in the American mineral industries. With 9000 members and. 27 local chapters scattered among the mining states, the Institute is in a peculiarly favorable position to know and to set out the feeling among mining men and metal-lurgists as to the proper scope of activities of these Federal bureaus, the quality of their work, and the gaps in knowl-edge that most need filling.

Jan 11, 1927

The ventilation of metal mines is becoming more of a fundamental requirement than it was 10 or even 5 years ago. There are many reasons for this, and in general they are based on economy or efficiency rather than health or safety, yet the latter enters into the picture in at least some instances. One Montana metal mine which had installed mine fans and a general ventilating system shut down the fan when there was a period of cessation of work; within a few weeks it was found that the underground timbers were becoming so covered with fungus that the fans were put into operation and thereafter continued in operation whether the mine was worked or not. The fungus soon disappeared and the cost of operating the fans was held to be far less than would be the numerous losses from timber decay which quickly started when cessation of air flow was encountered. A large iron ore mine in Michigan had much difficulty in holding men in a slicing region due to foul air under certain surface conditions as to direction of wind. Upon the placing of a moderate sized fan on the surface with some doors, stoppings and regulators underground, not only was the bad air condition removed but there was found to be a decided increase of tonnage per man per shift and timber decay was retarded to a very considerable extent. This particular mining company was rather inclined to be angry when I called attention to some of the what I considered very bad working conditions underground, and the mine superintendent for about a year and a half was on anything but friendly terms with me. Later on when the effect of the placing of the fan was found (the fan had been placed over his protest), that, man came through very nicely with a letter and congratulated me on the recommendation made and congratulated himself and the company on the conditions obtained after the installation of the fan. Poisonous Fumes after Blasting A copper mine in the Southwest with an ore of a high sulfide content has much difficulty due to poisonous fumes after blasting, and the, fan installation is as elaborate as those of many of the most nearly up-to-date coal mines, and coal mine splitting and regulating practices are being

Jan 1, 1927

By R. P. Carreker

ONE of a series, this report is concerned with the experimental documentation of the deformation behavior of pure metals over a wide range of temperature. Previous reports in the series describe the creep behavior of platinum1 and aluminum2 and the tensile behavior of copper,&apos; silver,& and molybdenum.5 Subsequent reports will describe the creep behavior of copper and silver and the tensile behavior of platinum, thus providing extensive creep and tensile data on four face-centered-cubic metals tested under comparable conditions. Material Two lots of high-purity aluminum were used in this investigation. One lot, designated AC, was obtained direct from the Aluminum Co. of America as high-purity aluminum in notch-bar form. A typical analysis of this type of aluminum is 0.006 pct Si, 0.015 pct Cu, 0.006 pct Fe, and 99.975 pct Al. Lot BS was obtained from J. I. Hoffman of the Bureau of Standards as a portion of the Aluminum A described in his report of the redetermination of the atomic weight of aluminum.6 Lot BS originated with the Aluminum Co. of America also, and was received in the standard notch-bar form. A detailed chemical and spectroscopic analysis of lot BS has been published.6 Principa1 impurities were 0.006 pct Si, 0.003 pct Fe, 0.002 pct Cu, and >99.987 pct Al. Samples were processed identically by room-temperature swaging and drawing to 0.030 in. diam wires from approximately ½ in. diam rods that were machined from the notch-bar pigs. Samples were cut from the cold-drawn wire, placed in a grooved graphite block in groups of thirteen, and annealed in air for 1 hr at each of several temperatures, with the results shown in Table I. The two lots of aluminum responded quite differently to annealing, the behavior of aluminum AC suggesting that its grain growth was controlled by impurities. The recrystallization texture of aluminum of similar purity comparably treated has been reported as predominantly <111> fiber with some <100> fiber present.7 Testing Procedure The testing procedure and method of analyzing the data have been described previously.2,3 Annealed specimens of 5 in. gage length were tested in an Instron tensile testing machine at a constant head motion corresponding to a strain rate of 0.04 min-&apos; at a number of temperatures. Instantaneous tenfold rate changes were employed in some tests to deter-

Jan 1, 1958

By Carle Hayward

THE effect of copper on steel has been studied by numerous investigators. Before modern testing methods had been developed, blacksmiths noted red shortness in iron, the cause for which was ascribed to the presence of copper. Numerous papers have been published on the corrosion of steels containing various amounts of copper, and a few writers have discussed the effect of copper on the mechanical properties of steel. The purpose of the investigation described in the following paper was to obtain additional data on the mechanical properties of medium-carbon steel containing small quantities of copper. Among those who have published results of mechanical tests on copper steels are Ball,1 who states that copper increases the tensile strength and &apos;hardness but lowers the elongation. Stead2 states that copper steels closely resemble nickel steels containing equivalent percentages of nickel,, as regards tensile strength, resistance to shock, corrosion and hardness. Wigham 5 found that copper in small amounts had no injurious effect on steel. Breuil4 found that with 1 per cent. carbon, copper lessened the brittleness of steel and in low-carbon steel it increased the tensile strength and lowered the ductility slightly. H. H. Campbell 5 states that copper up to 0.25 per cent. slightly raises the elastic limit, elongation and reduction of area.

Jan 1, 1918