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By E. C. Pechin

AT the suggestion of some members of the Institute, attention is called to the record of the working of Dunbar Furnace during the twelve months ending in January, 1874. During this period, with a product of over eleven thousand gross tons, not a single ton of

Jan 1, 1874

[VOL. XXXVI. Page. Line. 155 29 For "Joachimstahl," read "Joachimsthal." 215 Foot-note 2. For " May, 1892," read " May, 1902." 216 21 For " ack-screw," read " jack-screw." VOL. XXXVII. 31 3 For "quantity of tons," read "quantity of slimes." 35 10 Expunge "recorded in Table VII." 37 24 Expunge "to." 38 33 For "page 89," read "page 9." 44 40 For "page 86," read "page 6." 47 In table, third line under heading "Excavators and Conveyors," expunge "per 40 ft. of."]

Jan 1, 1918

By Elbert Rowland

THE widespread interest in the alloys of beryllium with copper is due principally to the fact that certain compositions show very favorable precipitation-hardening characteristics and are, in fact, the strongest nonferrous alloys known at the present time. Investigations have been conducted by Masing and Dahl and others on the physical characteristics of ternary beryllium alloys, in an attempt to produce precipitation-hardening effects with a smaller amount of beryllium than that required in the binary copper-beryllium alloys (2.0 to 2.5 per cent Be). The results of these investigations show that ternary alloys of beryllium with Cu-Sn, Cu-Al and Cu-Zn, among others, exhibit promising improvements in physical properties after precipitation-hardening treatment and, while the increases in properties obtained are not as high as those realized from the binary copper-beryllium alloys, excellent properties are obtained with beryllium contents averaging about one-half the amount required in the binary alloys. This paper presents the results of an investigation of the equilibrium relations of certain alloys containing copper, tin and beryllium. The alpha-phase boundary of the ternary system is given for alloys containing from 0 to 1 per cent beryllium. The equilibrium conditions beyond the alpha-phase boundary are presented for alloys containing up to 32 per cent tin and 1 per cent beryllium. The data were collected by means of

Jan 1, 1935

By J. P. Nielsen, H. Margolin, E. Ence

The Ti-Ni phase diagram has been investigated up to 68 pct Ni with iodide titanium base alloys by metallographic, X-ray, and melting point methods, and from 68 to 90 pct Ni by examination of as-cast structures of sponge titanium base alloys. NVESTIGATION of the nickel-rich portion of the I Ti-Ni phase diagram was first reported by Vogel and Wallbaum in 1938.' This work was subsequently extended to lower nickel contents by Wallbaum' who indicated the possibility of a eutectic reaction for nickel contents below 38 pct. Long et al.3 studied the titanium-rich portion of the phase diagram and found eutectic and eutectoid reactions below 38 pct Ni. However, the temperature of the eutectic indicated by Long et al. was considerably lower than that suggested by Wallbaum. Long and his coworkers synthesized their alloys by powder metallurgical techniques and encountered oxygen and/or nitrogen contamination. Thus the diagram which was obtained did not represent binary alloying conditions. However from these results the features of the binary diagram were predicted. At Battelle Memorial Institute4 the Ti-Ni diagram was investigated up to approximately 11.5 pct Ni with sponge titanium alloys. The range of temperatures used was not sufficient to define the eutectoid temperature or composition. The data of Wallbaum2 and Long et al.8 were of particular interest for the present study, and although the work was originally concerned with the region below 40 pct Ni, the investigation was extended to higher nickel contents in an attempt to resolve the differences between these workers. Experimental Procedure Preliminary work on the Ti-Ni system was carried out with duPont Process A sponge titanium alloys to reduce the amount of subsequent work to be done with iodide titanium base alloys. The sponge titanium used contained 99.71 to 99.77 pct Ti, 0.1 pct Fe and 0.005 to 0.009 pct Ni. The iodide titanium obtained from the New Jersey Zinc Co. contained 99.9 to 99.95 pct Ti. Nickel used with sponge titanium was 98.9 pct pure. The high-purity nickel alloyed with iodide titanium was cobalt-free with approximately 0.05 pct C and was obtained through the courtesy of the International Nickel Co. The 15 g sponge titanium charges for melting were prepared by compacting in a die or by placing the weighed portions of nickel and titanium directly into the furnace. Iodide titanium charges were made by drilling holes in the as-received rod and inserting the nickel or by wrapping the nickel in sheet. Sponge titanium alloys containing from 0.2 to 90 pct Ni and iodide titanium alloys containing 0.2 to 68 pct Ni were prepared by these methods. In addition to these alloys several 1/2 1b sponge titanium alloys were supplied by the Allegheny Ludlum Co. The charges were melted in an arc furnace under an argon atmosphere. The procedures used were similar to those reported in the literature5,' and the furnace has been described.' Except for iodide titanium alloys with 40 to 68 pct Ni (see section on copper contamination), each alloy was melted for 1 min, then either turned over or broken before re-melting for an additional minute. Currents of 200 to 400 amp were used depending on the melting point of the alloy. Prior to heat treatment, alloys containing less than 14.5 pct Ni were hot-forged at 750°C. With the exception of alloys in the homogeneity range of the compound TiNi, alloys of higher nickel contents could not be hot-forged. Heat treatment of iodide titanium base alloys was carried out in argon-filled quartz capsules which were broken under water at the conclusion of heat treatment to quench the specimens. Temperatures were controlled to ±5oC and annealing times up to 48 hr were used. For melting point determination, specimens were placed in carbon crucibles which were in turn en-capsuled in argon-filled quartz capsules. The start of melting was determined by rounding of corners and by metallographic examination. Complete melting was considered to have occurred at that temperature at which the specimen assumed the shape of the crucible. Specimens were prepared for metallographic examination by mechanical polishing or by an electrolytic procedure." For alloys containing up to 80 pct Ni Remington A etch7 50 pct glycerine, 25 pct HNO,, 25 8 HF) was used. For higher nickel alloys aqua regia and Carapella's etch (5 g FeCl,, 2 ml HNO,, and 99 ml methyl alcohol) were employed. Specimens to be exposed for powder patterns were prepared by filing, by breaking specimens in a

Jan 1, 1954

Many definitions have been advanced and many limitations advocated in the use of the terms, veins, lodes and ledges. The following definitions appear to follow the best usage. [ ] A fissure vein, according to Lindgren, is a mineral mass tabular in form as a whole, though often irregular in detail, filling or accompanying a fracture or series of closely set and intimately related parallel fractures in the enclosing rock, the mineral mass having been formed later than both the country rock and the

Jan 1, 1932

By Harvey Brooks

Jan 1, 1963

Jan 1, 1881

By Charles H. Fulton

There are comparatively few accurate data on the melting-or the freezing-point temperature of metallurgical slags, or on related physical phenomena, such as fluidity near the melting-point, specific heat, latent heat, etc. With the exception of the work of H. 0. Hofman,' and some older work by R. Akerman, P. Gredt, and H. M. Howe, no information is available that is of direct interest to the metallurgist. Hofman's valuable work is the only one that refers to slags produced in the metallurgy of copper and lead. The classic work of J. H. L. Vogt,2 who views slags from the standpoint of physical mixtures (solutions in which the entities are minerals), has opened up a new field in the study of slags, and has placed the investigation of such properties as melting-temperatures, etc., on a rational basis. The recent work of A. L. Day, E. T. Allen, and W. I?. White, of the Carnegie Institution, at Washington, and of European investigators3 on certain systems of silicate minerals confirms the value of the investigation of silicate series from this standpoint, and it is my aim to apply this method to metallurgical slags, in order to gain exact data of value in metallurgy. The work recorded in the present paper is the result of an investigation of reverberatory-furnace slags made for a Western smelting company to determine exactly the influence of change in composition, within comparatively narrow limits, on the melting-point. For a general discussion concerning the mineralogical character of slags and the principles on which this investigation is based, reference should be made to other work: for the subject is too large to be stated in this paper, except very briefly in the following outline:

Jan 1, 1913

Jan 1, 1898

Sec. 1. The membership of the Institute shall comprise six classes, namely: 1. Members; 2. Honorary Members; 3. Senior Members; 4. Associates; 5. Junior Members; 6. Rocky Mountain Members. All shall be equally entitled to the privileges of membership, excepting that no member of any class whom residence shall be outside of the United States of America, except those residing in Mexico and Canada, shall be entitled to vote. SEC. 2. Members: A person to be eligible for election or transfer into the claw of Member must be at least 27 years of age and must have had at least six years' employment in the practice of engineering, mining, geology, metallurgy, or chemistry, during at least three years of which he must have held positions of responsibility in one or more of these fields. This shall not apply to Rocky Mountain members.

Jan 1, 1944

By C. R. Ramachandra, C. C. Patel

Flotation of chalcopyrite from a low grade ore was studied by using different xanthates and dixanthogens as collectors and by conditioning the flotation pulp with oxidizing gaseous systems. The improvement in the recovery of chalcopyrite with the oxidizing systems was mainly due to the auto-activation of chalcopyrite, leading to the enhanced adsorption of xanthates and dixanthogens even when the latter were formed by oxidation of the xanthates. With air or oxygen as oxidizing system, the amount of ethyl xanthate required at pH 8.5 was much less than normally employed in the industry, the recovery being 97-99% of chalcopyrite with a concentrate of 24% copper. With isopropyl and isoamyl xanthates, the recovery was improved but the grade was lowered. By conditioning the pulp with air-CO2 or oxygen-CO2 mixture, the recovery was lowered with ethyl xanthate only, mainly due to the depressant action of bicarbonate formed. Flotation with dixanthogens gave cleaner concentrates of chalcopyrite. because iron pyrite did not float with these collectors. Of the dixanthogens tried, diisopropyl dixanthogen gave the highest recovery, 99% chalcopyrite with a concentrate containing 28.5 to 30% copper, when the pulp at pH 8.5 was condi-tioned with air. Isopropyl dixanthogen was found to be the best collector of all the xanthates and dixanthogens studied. It was found that the adsorbed ethyl, isopropyl and isoamyl xanthates at chalcopyrite surface, activated by cupric sulfate, and at iron pyrite surface were oxidized to the corresponding dixanthogens to different degrees in presence of air, oxygen, air-carbon dioxide mixture and oxygen-carbon dioxide mixture.' The dixanthogen formed at chalcopyrite surface was, however, firmly adsorbed while that at iron pyrite surface was easily desorbed. Since dixanthogens formed have greater hydrophobicity than the corresponding xanthates, as revealed by contact angles,1,2 the former were expected to improve the flotation results. It was, therefore, thought desirable to find out the effect of air, oxygen, air-carbon dioxide mixture and oxygen-carbon dioxide mixture on the selective flotation of chalcopyrite when individual xanthates were used as collectors. The effect of direct use of dixanthogens as collectors on the selective flotation of chalcopyrite was also investigated. For these studies, low grade chalcopyrite ore, received from the Indian Copper Corp., Ltd. (I.C.C.), Ghatsila, Bihar, was employed. At the milling plant of the I.C.C., chalcopyrite is floated at a pH of 8.5, employing ethyl xanthate as collector. EXPERIMENTAL Materials Employed: XANTHATES - Ethyl, isopropyl and isoamyl xanthates of potassium were prepared in a pure state by the methods described earlier.4 A 0.03% aqueous solution of a xanthate was freshly prepared in air-free distilled water for flotation studies. DIXANTHOGENS - Diethyl, diisopropyl and diisoamyl dixanthogens were prepared by the oxidation of xanthates by iodine and purified by extraction with petroleum ether. A 0.03% alcoholic solution of dixanthogen was used as a collector. FROTHER - A 0.2% solution of pine oil in ethyl alcohol was employed. SODIUM CARBONATE - A 0.4 N solution was used. ORE - The composition of the -100 +200-mesh size (Tyler standard) powdered ore, as determined by standard methods of analysis, was: copper 1.57%, iron 10.29%, sulfur 3.15% and acid insolubles 66.10%. Iron present as chalcopyrite (CuFeS2) was 1.38%, while that present as iron pyrite (FeS,) was 1.37%. Both chalcopyrite and iron pyrite were found to be liberated from the gangue minerals and from each other, as observed under a microscope. Flotation of Chalcopyrite with Xanthates in Presence of Different Gaseous Systems: Fifteen grams of -100 + 200-mesh size ore were shaken well with 100 ml of distilled water. The pH of the pulp was adjusted to 8.5 by the addition of sodium carbonate solution. Then 0.1 ml of xanthate solution (0.005 lb xanthate per ton of the ore) was mixed with the pulp, and the latter together with washings transferred to a

Jan 1, 1963

By John H. Hearding

Induction heating, together with automatically controlled tempering and hardening is giving Oliver faster and more accurate bit sharpening, while experiments with bit taper promise to offer increased footage per bit.

Jan 10, 1953

By Kichizo Niwa, Toshio Yokokawa, Mitsuo Shimoji, Yoshihiko Watanabe, Satoshi Kado

A LTHOUGH a systematic research on diffusion in liquid metals has not been carried out, partial studies have been developed by various workers in several systems. A few recent papers among them have shown that this line of approach is quite useful for understanding the structure of the liquid state. Furthermore, it has been found in kinetic

Jan 1, 1958

By E. H. Dix

All commercial aluminum contains small percentages of copper, iron, and silicon as unavoidable impurities. The purest metal obtainable commercially, special grade high purity ingot, contains a maximum of 0.50 per cent. impurities of which the usual minimum amount of copper is 0.01 per cent.; silicon, 0.12 per cent.; and iron, 0.20 per cent. This grade is too costly for most purposes. The two standard grades, Nos. 1 and 2, containing a minimum of 99.0 and 98.0 per cent. aluminum, respectively, are more generally used. Other grades of secondary aluminum often contain as high as 3 or 4 per cent. of impurities, which include 1 per cent., or more, of zinc. Specifications for high-grade aluminum-casting alloys generally allow a maximum of 1.7 per cent. for total impurities. The S. A. E. Specification No. 33, which is intended to cover alloys made from secondary aluminum ingot, gives the iron maximum as 1.5 per cent. and the maximum for silicon (including manganese and tin) as 0.75 per cent. The effect of even relatively small amounts of impurities on the physical properties of ingot aluminum is shown by the following cornparison of two lots of aluminum, which may be taken as representative of special grade and grade No. 2 ingot, respectively. AnalysEs Special Grade, Gbade No. 2, Per Cent. PeR CBnt. Copper................................. 0.01 0.32 Silicon................................. 0.12 0.32 Iron................................... 0.42 0.82 Aluminum.............................. 99.45 98.54

Jan 1, 1923

By E. H. Dix

All commercial aluminum contains small percentages of copper, iron, and silicon as unavoidable impurities. The purest metal obtainable commercially, special grade high purity ingot, contains a maximum of 0.50 per cent. impurities of which the usual minimum amount of copper is 0.01 per cent.; silicon, 0.12 per cent.; and iron, 0.20 per cent. This grade is too costly for most purposes. The two standard grades, Nos. 1 and 2, containing a minimum of 99.0 and 98.0 per cent. aluminum, respectively, are more generally used. Other grades of secondary aluminum often contain as high as 3 or 4 per cent. of impurities, which include 1 per cent., or more, of zinc. Specifications for high-grade aluminum-casting alloys generally allow a maximum of 1.7 per cent. for total impurities. The S. A. E. Specification No. 33, which is intended to cover alloys made from secondary aluminum ingot, gives the iron maximum as 1.5 per cent. and the maximum for silicon (including manganese and tin) as 0.75 per cent. The effect of even relatively small amounts of impurities on the physical properties of ingot aluminum is shown by the following cornparison of two lots of aluminum, which may be taken as representative of special grade and grade No. 2 ingot, respectively. AnalysEs Special Grade, Gbade No. 2, Per Cent. PeR CBnt. Copper................................. 0.01 0.32 Silicon................................. 0.12 0.32 Iron................................... 0.42 0.82 Aluminum.............................. 99.45 98.54

Jan 1, 1923

By B. J. Shaw, R. Kossowsky, W. C. Johnston

High purity (99,95) Ni-51 wt pct cr eutectic alloy was unidirectionalty solidified at rates of 0.1 to 8 in. per hr. The resulting material was characterized by large grains, approximately 0.5 mm in cross section and extending through almost the entire length of the specimen, parallel to the growth axis. The eutectic structure of specimens the growth at -1/3 The per hr consisted of a continuous nickel-rich phase and chrome -rich lamellae approximately 2 thick, spaced about apart. Specimens were tested in compression at temperatures ranging from —196 to 850"C over which range the 0.2 pet yield strength dp -creased from 160,000 p si to 35,000psi, respectively. Swaging to 40 pet reduction in area, followed by a 30-min anneal at 1000c to remove residual cold work, increased the 0.2 pet yield to 260,000 psi at -196°C, dropping to 35,000 psi at 850°C. The increase in strength was attributed to a residual cell structure. The strength of the alloy could be rationalized by the simple rule of mixtures if one assumed that additional strength is derived front a size effect characterized by is petch equation IN recent years there has been increasing interest in dispersion and second phase strengthening in materials needed for high-temperature applications. inm role of structure on the mechanical The of such alloys has been well established of such some extent accounted for theoretically. and to of how the strengthening mechanisms due to fibers and lamellae operate has been reduced to its fibers form by the fabrication of composites of strong rods unidirectionally aligned in a From work on tungsten-fiber-reinforced copper, for example, it was established that the "Rule of Mixtures" could explain the strengthening.12 " some what more sophisticated technique for introducing strong fibers into copper matrix was used by Hertzberg strong Kraft3 who unidirectionally solidified the copper-chromium eutectic. The use of unidirectionally fied eutectics has advantages in that there are no matrix-fiber wetting problems and fine fibers are automatically aligned and uniformly fiber However, one Is restricted to a specific volume fraction of the second phase. Nevertheless, even though the volume fraction is fixed, the rod or lamella thickness, , can be varied by controlling the freezing interface velocity. Alternatively, the grown material may be worked down by swaging or rolling. Embury and Fisher, " using this approach, drew down pear lite in iron and studied the mechanical properties iron and that the yield strength, oy, was properties.proportional They that d was the wire diameter. It could be inferred that was also proportional to but the work hardening had to be taken into consideration at the same time. By varying the growth rate of the cadmium-zinc lamellar eutectic, Shaw'1 showed that was proportional to without the introduction of work hardening and suggested that the lamellar interface itself contributed to the strengthening of the composite. In this investigation we have evaluated the mechanical properties of the unidirectionally solidified fec-bec eutectic Ni-Cr. This eutectic was selected because it presented the possibility was selected beca temperature, and high corrosion resistant alloy, and also represented a hard-soft phase combination with two completely different slip systems. Specimens were tested in compression and tension up to 850°C and a detailed study of the micro structure as a function of plastic strain and temperature was carried out by light and electron microscopy. It was shown that the composite strength tested in compression can be accounted for by the simple rule of mixtures if one allows for an additional term representing the effect of Intereprese EXPERIMENTAL PROCEDURE 1) Unidirectional Solidification. Fig. 1 is a schematic drawing of the apparatus used to produce 0.2 in. diam by 12 in. long alloy ingots. The crucible tube is alumina, containing the charge which has been is swaged, or machined to 0.195 in. diam. The lower end of the tube is immersed to 0 .195in in.d iam. The upper end is supported by a 10 mil nichrome wire which lowers the crucible mil nic hr the] wire at a prescribed rate. Surrounding the furnace is a graphite susceptor into which a control thermocouple is inserted. The furnace is insulated with fiberfrax and enclosed in a quartz tube. There is a sliding seal at the bottom around the crucible and one on the top so that an atmosphere may be used for the sample and suscep tor. The power for the furnace is supplied from a 10-kw, 450 kc generator. The skin depth (the skin depth at which the field falls to l/e of its value at the outer surface) for graphite (p = 10 (j-ohm-cm) is 0.1 in. at this fre-

Jan 1, 1970

By E. M. MacKevett

The only source of uranium ore in Alaska that has been mined commercially is the Ross-Adams de- posit, a gently inclined, fusiform orebody in alkali granite in which uranothorite and uranoan thorianlte are the chief ore minerals. In mode of occurrence, apparent genetic association with the granite, and to a lesser extent in mineralogy, this type of deposit is uncommon. The mine is in the southern part of Prince of Wales Island (Fig. 1) at an altitude of about 950 ft on the southeast flank of Bokan Mountain. A steep unpaved road 1 ¾ miles long leads to the dock on the West Arm of Kendrick Bay, which can be reached by boat or seaplane from Ketchikan, some 35 miles to the northeast.

Jan 9, 1959

By Frank H. Skelding

Still the world's largest producer, consumer and importer/exporter of minerals, the United States has, in recent years, become more and more aware of the many diverse forces that increasingly affect its ability to maintain free access to and trade in minerals, both domestically and abroad. The nation's growing dependence upon foreign sources of minerals in the face of mounting competition is causing many changes, not only in the mineral industries, but in national attitudes and policies as well. This paper examines the position of the United States in the world mineral economy relative to the significant trends that have and are developing. It attempts to define and evaluate the major present and future impact of these trends and to anticipate the probable effects upon the U.S. and its mineral economy.

Jan 1, 1976

By B. Egeberg, H. B. Smith

Britannia metal is a white alloy consisting primarily of tin and antimony, the tin greatly predominating. The alloy usually contains a small amount of copper and occasionally very small amounts of one or two other metals, such as bismuth, zinc, and lead. It is capable of being cold-rolled, it takes a high polish, and it is fairly noncorrosive; properties which make it a popular metal for many household and traveling utensils. Britannia metal is similar in many respects to pewter and has largely replaced pewter in the arts, but it should not be confused with that alloy, because pewter is essentially a tin-lead alloy, while Britannia is a tin-antimony alloy. In view of the fact that so little has been published concerning Britannia metal, the authors feel justified in presenting the results of their investigation, particularly since the behavior of this alloy under cold rolling and heat treatment differs so greatly from that of other metals and alloys. The old craftsman, engaged in the making of ornaments or tableware, heated the cold-rolled sheet metal or his finished product to a straw color corresponding to about 375" I?., claiming to produce thereby a harder and more rigid article. The fact that possibly led him to this heating was that a reheated article or sheet made from Britannia metal has a distinct metallic ring when struck a sharp blow, whereas an unheated article or sheet has a leady, dead note. No doubt he has associated the metallic ring with a greater rigidity and strength, and justly so, as will be seen later. The approximate analysis of the metal we investigated was 91 Sn, 7 Sb, 2 Cu, and the molten metal was bottom-poured into an iron mold yielding an ingot 7 3/4 in. wide by 11 in. long and % in. thick, the casting temperature being 800" F. The ingot was cold-rolled to a sheet 0.032 in. thick, sufficiently large samples for experimental purposes being cut from the sheet at intermediate stages. The samples were all tested for hardness with scleroscope and Brine11 machine, then heated to 212" F. for 30 min., and again tested after cooling to room temperature. The same samples were heated successively at 300°, 400°, and 440" F., followed

Jan 1, 1929

By H. B. Smith, B. Egeberg

Britannia metal is a white alloy consisting primarily of tin and antimony, the tin greatly predominating. The alloy usually contains a small amount of copper and occasionally very small amounts of one or two other metals, such as bismuth, zinc, and lead. It is capable of being cold-rolled, it takes a high polish, and it is fairly noncorrosive; properties which make it a popular metal for many household and traveling utensils. Britannia metal is similar in many respects to pewter and has largely replaced pewter in the arts, but it should not be confused with that alloy, because pewter is essentially a tin-lead alloy, while Britannia is a tin-antimony alloy. In view of the fact that so little has been published concerning Britannia metal, the authors feel justified in presenting the results of their investigation, particularly since the behavior of this alloy under cold rolling and heat treatment differs so greatly from that of other metals and alloys. The old craftsman, engaged in the making of ornaments or tableware, heated the cold-rolled sheet metal or his finished product to a straw color corresponding to about 375" I?., claiming to produce thereby a harder and more rigid article. The fact that possibly led him to this heating was that a reheated article or sheet made from Britannia metal has a distinct metallic ring when struck a sharp blow, whereas an unheated article or sheet has a leady, dead note. No doubt he has associated the metallic ring with a greater rigidity and strength, and justly so, as will be seen later. The approximate analysis of the metal we investigated was 91 Sn, 7 Sb, 2 Cu, and the molten metal was bottom-poured into an iron mold yielding an ingot 7 3/4 in. wide by 11 in. long and % in. thick, the casting temperature being 800" F. The ingot was cold-rolled to a sheet 0.032 in. thick, sufficiently large samples for experimental purposes being cut from the sheet at intermediate stages. The samples were all tested for hardness with scleroscope and Brine11 machine, then heated to 212" F. for 30 min., and again tested after cooling to room temperature. The same samples were heated successively at 300°, 400°, and 440" F., followed

Jan 1, 1929