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By H. D. Kessler, R. J. Van Thyne

Phase diagrams of the titanium-rich portion of the ternary systems from 0 to 10 wt pct Al and 0 to 1 wt pct 0, N, and C were determined. Micrographic analysis of annealed high purity arc melted alloys was the principal method of investigation and was supplemented by X-ray diffraction. TITANIUM-ALUMINUM alloys exhibit excellent properties, particularly for elevated temperature use. For this reason, the Materials Laboratory, Wright Air Development Center, sponsored an investigation of the effect of the interstitially soluble contaminants, oxygen! nitrogen, and carbon, on the Ti-A1 system. Using high purity arc melted alloys and micrographic analysis of annealed samples as the chief method of investigation, titanium-rich partial phase diagrams were determined for the ternary systems. Experimental Procedure Materials: The titanium used in the preparation of the alloys was iodide crystal bar (99.9+ pct pure) produced by the New Jersey Zinc Co. and Foote Mineral Co. The aluminum was obtained from the Aluminum Co. of America in the form of sheet. The given analysis was: Si, 0.0006 pct; Fe, 0.0005; Cu, 0.0022; Mg, 0.0003; Ca, <0.0006; Na, <0.0005; and Al, 99.99. High purity titanium dioxide purchased from the National Lead Co. was used in the preparation of the oxygen-bearing alloys. The spectrographic analysis of this material was as follows: SiO,, 0.07 pct; Fe,O,,, 0.002; A1,0,, <0.001; Sb,O,, <0.002; SnO,,, <0.001; Mg, <::0.001; Cb, <0.01; Cu, 0.0004; Pb, 0.002; Mn, <0.00005; W, <0.01; V, <0.002; Cr, <0.002; Ni, <0.001; and Mo, <0.002. Special spectroscopic graphite rod purchased from the National Carbon Co. was used in the preparation of the Ti-A1-C alloys. Alloy Preparation: Alloy ingots weighing 10 grams were melted in a nonconsumable tungsten electrode arc melting furnace using water-cooled copper hearths and a helium atmosphere. The arc was struck on a tungsten stud in the copper block to minimize contamination from the electrode. Details of the techniques have been reported.&apos;, &apos; Each ingot was inverted and remelted a minimum of four times to insure homogeneity, without opening the furnace. Remelting small control ingots of iodide titanium under similar conditions resulted in no measurable hardness increase, indicating contamination-free melting conditions were used. The alloy charges and resultant ingots were weighed to the nearest milligram. Only small weight losses were obtained upon melting, indicating that the actual compositions were very close to the nominal compositions. Check analyses substantiated this. Oxygen and nitrogen were added during ingot preparation as master alloys. An oxygen master alloy containing 25 wt pct 0 was prepared by melting iodide titanium and pressed titanium dioxide (40 pct 0) powder. The Ti-25 pct 0 alloy is more easily handled during weighing and charging than the pressed TiO, powder. Chemical analysis indicated that titanium-nitride received from an outside source contained large amounts of impurities (2.7 pct Ca). Therefore, a master alloy containing approximately 12 pct N was prepared by melting nitrided sponge titanium. As the sponge melted with difficulty, the alloy was diluted by addition of titanium to lower the melting point. The chemical analysis of the final alloy was 6.69 pct N. Both master alloys are friable and were used as —8 +16 mesh lumps resulting from crushing the ingots. NIelting the Ti-A1-0 and Ti-A1-N compositions five times produced homogeneous ingots. The preparation of homogeneous carbon-bearing alloys caused considerable difficulty. Alloys containing less than 1 pct C were prepared using spectrographic graphite rod, 1/8 in. diameter by 1/8 in. long. However, the graphite did not dissolve even with long melting times and many remelts. The ?/s in. pieces of graphite were used rather than powder because the low density powder is troublesome in arc melting.

Jan 1, 1955

"In the spring of 1927, six members of the American Institute of Mining and Metallurgical Engineers met for dinner at the Chemists&apos; Club in New York to discuss the possibility of setting up a committee within the Institute to further the current interest in the science of steelmaking. Attention&apos; to this subject had been crystallized by a symposium held by the Faraday Society in 1925. &apos; After a prolonged discussion, ranging from thermodynamics to slag conditioning, it was decided to approach the Institute with the request that a standing committee on "The Physical Chemistry of Steel Making" be set up. This committee proposed to promote scientific and practical papers on the subject, and was designed to cooperate with the Open Hearth Committee of the Institute in bringing scientific developments to the attention of open-hearth operators throughout the country... . "As the life of the [Physical Chemistry of Steelmaking] Committee lengthened and general interest in the technical phases of steelmaking grew, it became evident that there was a distinct need for a book that might serve the open-hearth interests to better advantage than standard texts whose scope is necessarily wide and whose detailed exposition of the open-hearth process is, therefore, somewhat limited. With this thought in mind, the Committee, after some years of consideration and debate, embarked on the venture of writing a manuscript on `Basic Open Hearth Steelmaking&apos;." The foregoing paragraphs, taken from the introduction by C. H. Herty, Jr. to the first edition, well describe the circumstances which led to the publication of "Basic Open Hearth Steelmaking" in the spring of 1944. The book consisted of nineteen chapters contributed by twenty-three authors and edited by the staff of Alloys of Iron Research and T. S. Washburn, B. M. Larsen, and J. S. Marsh with Frank T. Sisco as consulting editor. The Engineering Foundation and the Open Hearth Steel Committee of the Iron and Steel Division, AIME, made financial grants; steel companies and other organizations supported the publication by contributing time and expenses of staff members in their capacity as authors or editors. The volume was sponsored by the Seeley W. Mudd Memorial Fund and appeared under the

Jan 1, 1951

By Robin O. Williams

Robin 0. Williams (Oak Ridge National Laboratory)— The authors have questioned the degree to which the coherency strains between the iron-rich and chromium-rich phases are isotropic as proposed in Ref. 5 on the basis of the difference between the elastic properties of the two phases. The relative magnitude of the stresses is determined by the moduli as shown by Eqs. [2], [3], and [4] of Ref. 34. However, the moduli of the two phases have no direct bearing on the uniformity of either the stress or strain within either phase. The idea that the strains are isotropic within each phase (but normally of different magnitude and always of different sign) is based entirely upon the experimental observation that X-ray line broadening has not been detected even when the particles become rather large. It has not proven possible to grow the particles sufficiently large that they lose coherency. Based upon this lack of line broadening one can estimate an upper limit for the nonuniformity of the strains within each phase as follows. It is considered possible to detect line broadening if it is as great as 10 pct of the separation of the K, doublet for the (211) line using chromium radiation. The doublet separation would correspond to a total strain of 0.0017 such that the total variation of lattice parameter relative to the average lattice is now k0.05x0.0017 or something less than ± * For the present case the strain in each phase is roughly 0.002 such that the variation of strain within a phase will not exceed 5 pct. It is stated that the expression derived for strengthening for the hydrostatic straining as observed in this system would substantially overestimate the magnitude due to dislocation flexure. This is contrary to the conclusion reached in the original paper34 for the present range of particle sizes. What is the lowest temperature at which a has been observed to form in this alloy? M. J. Marcinkowski, R. M. Fisher, and A. Szirmae (nutlzors&apos; reply)— -Williams&apos; arguments based on X-ray findings for a chromium-rich precipitate and an iron-rich matrix strained to a common lattice parameter are certainly convincing. This being the case, there are no shear components of strain associated with the precipitate-matrix aggregate to interact with the shear components of the dislocation stress fields, contrary to the opinion expressed by the present authors. On the other hand, the present authors, in spite of this error, did not expect the shear interactions to be significant. The chief objection to Williams&apos; model in the present case is that the various segments of the dislocation line are assumed to pass from one potential valley to the next independently of neighboring segments. This is only true for a highly flexible dislocation line, i.e., one whose radius of curvature is something less than the center to center distance between precipitate particles which amounts to about 90A in the present alloy. In order to maintain this curvature, an externally applied shear stress of at least 230,000 lb per sq in. would be required or about four times the observed stress. It is therefore concluded that the dislocation lines move rather rigidly through the lattice. This being the case, the forces on the dislocation resulting from the hydrostatic interaction between the stress fields of the edge-dislocation components and the precipitate particles should average out to zero; that is particles above the below the slip plane produce forces on the dislocation of opposite sign and therefore will cancel when averaged over the entire length of the dislocation. On the other hand, since the dislocation is not perfectly rigid, Williams&apos; model may lead to some strengthening, but far less than that predicted. A second and equally serious objective to using Williams&apos; strengthening model for the present alloys is that profuse wavy slip due to the motion of screw dislocations played a predominant role not only in the unaged alloys but in the fully aged ones as well. Since the screw dislocation has associated with it only shear components of stress the hydrostatic strengthening model no longer applies. In view of these arguments the present authors must reject Williams&apos; model of strengthening as being pertinent to the present alloy system. The present authors have made no detailed study of the lowest temperature at which a forms in the quenched ferritic alloys. None was ever observed n the alloys aged at 500°C so that forma-tion must occur at temperatures higher than this and was therefore not a factor in the present study.

Jan 1, 1965

By T. J. Whalen, M. Humenik

The liquid surface tension of copper-nickel ad copper-nickel-titanium-carbon alloys and the wettability of titanium caybyde by these alloys have been measuhed. It was found that the surface tensions of the binary copper-nickel alloys Lie on a smooth curve between the end members, copper and nickel. The addition of small amounts of titanium and carbon has nO effect on the surface tensions of copper-nickel alloys. Small additions of nickel to copper significantly reduce the contact angle of Ike alloy with titanium carbide. From a Gibbs treatment, nickel is shown to be adsorbed at the titanium carbide-alloy interface. X HE microstructure of two-phase materials has been shown to be influenced largely by the interfacial energies between the phases present.&apos; , In systems prepared by powder metallurgy techniques and densi-fied in the presence of liquid phase, a precise analysis of microstructure and interfacial energy relationships requires a knowledge of the solid-solid interface energies and liquid-solid interface energies. However, marly metal-nonmetal systems are characterized by the "sweating" of the liquid during sintering, and in these systems wettability is a principal consideration. The wetting in turn is dictated by the various interface energies of the system, as shown in Fig. 1 for a liquid drop formed on a solid substrate. The equation which expresses the vectorial balance of surface forces in the horizontal plane, at the point of contact, A, is given by: where ssv = solid-vapor interface energy sSL = solid-liquid interface energy sLV= liquid-vapor interface energy 6 = contact angle measured through the liquid phase. The angle and the surface tension, slv, can be measured accurately by the sessile drop method.3, The absolute value of the surface energy of the solid cannot be determined by this method, but with reasonable changes in the composition of the liquid only, the value of ssv can be considered constant. The changes in contact angle, then, can be attributed to changes in sSL and sLV and since sLV can be measured, the changes in sSL can be determined. Several studies have indicated that the surface and bulk properties of solid alloys can be correlated with electronic structure. The catalytic activity of copper-nickel alloys was reported to follow the dband vacancies in these alloys.5 Nickel has been considered to have 0.6 holes per atom in the d-band. The addition of copper to nickel is thought to bring about a filling of the d-band of nickel, since each copper atom contributes one electron. Thus, at an atomic concentration of 60 Cu-40 Ni (62 wt pct Cu-38 wt pct Ni) the d-band is believed to be full, and magnetic measurements support this view.6 If the electronic structure is influencing a property of the alloy, this property should show some sort of discontinuity as the composition changes from one side of the 60 Cu-40 Ni composition to the other. Since the catalytic activity can be considered as a surface property of the alloy, it is logical to assume that other surface properties, such as surface tension, may also be influenced by electronic structure. The suggestion has been made that there is a correlation between the solid titanium carbide-liquid Cu-Ni alloy interfacial energy and d-band filling.7 One purpose of this investigation was to determine if the changes taking place in the electronic structure with compositional changes in the solid copper-nickel alloys were reflected in the surface tension values of the liquid alloys. Such a change, if present, would lend support to the suggestion that one can refer to discrete energy bands in the liquid state. Other purposes of the present study were to investigate in detail the wettability in the system copper-nickel-titanium carbide, and to discuss the possible processes which take place during wetting in this system.

Jan 1, 1961

By A. D. Schwope, L. R. Jackson, K. F. Smith

Burghoff and Blank1 have pointed out that the creep properties of hard-drawn coppers are closely associated with their individual softening characteristics and have further shown that the creep resistance of various types of copper is improved, under certain circumstances, by cold stretching. In the design of certain types of electrical machinery, it is important to have the creep resistance as high as possible; furthermore, short-time creep strength is important since in many cases stresses are large only during warming-up and cooling-down periods. In this paper, data are presented showing the effect of cold work on the short time creep strengths of various types of commercial copper under several conditions. It is shown that trends from short-time creep tests are evident at longer times. Materials Used in the Investigation The coppers used in this investigation were commercial grade and of two basic types, oxygen free high conductivity (OFHC) and tough pitch. Additions of silver in amounts of 15 and 25 oz per ton were added to each of the two coppers. The analyses of these six coppers are given in Table 1. Originally, they started as wire bars 4 X 4 X 54 in. A. square rod was made by hot rolling the wire bars to 9/16-in. rod in 8 passes. This rod was then cold drawn to 0.445-in.-diam rod and annealed for 3 1/2 hr at 1000°F. It was then cold drawn to 0.325-in. rod and again annealed at 1000°F for 3 1/2 hr. Hard square rods were then made by cold rolling to 0.257 X 0.257-in. rod. Soft wire was made from the hard- drawn material by annealing at 650°F for 3 hr. The final rolling was performed using a set of 9-in. grooved rolls revolving at 30 rpm, which produced square wires. Reductions of approximately 5, 20, 30, and 40 pct were obtained using several passes in the same direction for the large reductions. The 5 pct reduction by drawing was accomplished using a steel die having 2 parallel bearing surfaces. The die angle was 7 1/2 degrees and the wires were lubricated with a paste of ceresin wax dissolved in carbon tetrachloride. The speed of drawing was 13 fpm. Since work was done on only two sides of the wire simultaneously, it was necessary to rotate it 90 degrees each pass to insure uniform deformation. The room-temperature tensile properties of the various tempers are given in Table 2. The grain size of the an- nealed 0.257-in. wires was uniform and averaged about 0.035-0.045 mm. Experimental Procedures for Short-time Creep Tests Standard creep-test frames (Fig 1) were used for the testing. Special fixtures were designed to apply axial compressive and tensile loads to the copper wires. The compression specimens were 1 in. long and the ends were ground flat and parallel. The creep in compression was indicated by the movement of reference marks s-ratched on intersliding platinum strips attached to the moving heads of the fixture. The movement was measured with an optical micrometer fitted with a filar eyepiece on which the smallest division was 0.00005 in. The tensile creep specirriens were 4 in. long which provided ample gripping surface for the jaw-type grips. The platinum strips were attached to a one-inch gauge length of the wire and the creep measured as previously described. The single-specimen furnaces were connected to individual power and control sources. The controlling equipment consisted of Foxboro controllers

Jan 1, 1950

By Thomas M. Drown

I DESIRE to communicate to the Institute the results of a few analyses which bear on the condition of carbon in gray and white iron. These analyses were made in the course of an investigation, now in progress, of the chemical composition of "chilling" irons. It will be remembered that Bell says he found no material difference in the amount and condition of carbon in gray and white pig iron made at the Clarence furnace, in England, and he therefore refers the difference in color and appearance in these two varieties of iron to the size of the particles of graphite. I quote from his "Chemical Phenomena of Iron Smelting:" "The inference I would draw from the information afforded by these analyses is, that the condition of iron in respect to its so-called &apos;richness&apos; is, within certain limits, entirely independent of its chemical constitution.. .. In the fluid state, I conceive the carbon, so taken up, confers upon the iron the property of fusion much below the temperature at which the pure metal melts, and the carbon itself may be regarded as dissolved in the iron. If, during the process of manufacture, the pig metal has been formed at a low temperature, consolidation, I imagine, takes place under such circumstances that the crystals are so minute, and the carbon which is separated assumes the uncombined or graphitic form in particles so minute as to be invisible, and, in consequence, the iron is white. If, on the other hand, the furnace is working at a very high temperature, the intensely heated iron crystallizes with large facets, upon which the extruded carbon assumes the condition of distinct plates or flakes. Should the temperature be less intense, these crystals are of smaller dimensions, and the separated carbon is less conspicuous, and, as the temperature of the furnace declines, the crystals decrease in size, as do the flakes of carbon, until both disappear in white iron.. .. Returning, then, to temperature as the cause of differences in quality of pig iron, the &apos;chilling&apos; of gray metal, and its conversion into white, may be regarded as the effect of preventing, by rapid cooling, the formation

By JOHN R. SUMAN

COMMENCEMENT exercises this year have a peculiar significance because the graduating students are entering upon their life&apos;s work at the most critical time in the history of the United States. We are engaged in a great struggle the outcome of which is none too clear even to the best informed students of international affairs. We are starting late in a vicious world conflict where it is generally recognized that our adversaries have distinct superiority over us in armament on the land, on the sea, and in the air. We have the gigantic task of building up our armed forces and armament and at the same time supplying our allies with equipment which they must have. We can do this job if we are given sufficient time, but there is a possibility that the war will be over before we are ready. Few realize the seriousness of this situation. If this fight is to be won-and we dare not try to visualize the future of this country if it is lost-all dissension and bickering between Congress, capital, labor, and agriculture must cease. When and where voluntary co-operation proves inadequate for the successful conduct of the war effort, laws must be enacted or strengthened to achieve our purpose.

Jan 1, 1942

By L. C. Brown, A. J. Stewart

Phase transformations have been studied in Ag-Zn alloys quenched from the high-temperature bcc 0 phase and lying in the composition range 37.4 to 50.0 at. pct Zn. On quenching, the alloy with the lowest zinc content transformed to massive a (fcc); all other alloys formed the ordered (3&apos; phase. On deformation, a martensitic reaction took place forming a close-packed structure. At Lou&apos; zinc contents transformation to this structure was complete. However, above 43 at. pct Zn a p.rogressively increasing amount of ß&apos; was retained following deformation. The close-packed structure was fcc at lower zinc contents (under 47 at. pct Zn) and either hcp or a mixture of fcc and hcp at high zinc concentrations. The structures produced by cold working were unstable and on aging transformed to the ß&apos; phase or the complex hexagonal to phase. For low zinc contents (under 43 at. pct) the fcc st-ructure transformed directly to the equilibrium To phase. With higher zinc contents, some 13&apos; was retained following defownation, and on aging the amount of this phase relative to the close-packed structure increased. On further aging both structures transformed cornpletely to PO. Metallographic examination indicated that the nature of the deformation product depended very markedly on the mode of deformation. Tensile deformation gave a microstructure characteristic of thermal martensite. KING and Massalski1 have shown that an alloy of Ag-50 at. pct Zn quenched from the high-temperature bcc ß phase undergoes a low-temperature ordering reaction forming ß&apos; which can be retained to room temperature. On deformation an hcp phase is produced, although this is unstable and the structure reverts completely to ß&apos; on aging. In the present paper, the work of King and Massalski is extended to cover a wide composition range in the p phase, observations being made of the structure of the quenched 13 and of the effects of deformation and aging. The relevant portion of the Ag-Zn phase diagram is shown in Fig. 1. King and Massalski have shown that close to stoichiometry the ß&apos; phase is the equilibrium structure at low temperatures. The approximate composition range of this phase, taken from a recent paper by Pops and Massalski,3 is shown on the phase diagram. The locations of atom sites are very similar in the ß&apos; and to structures, and the 4, structure can be derived from the 0&apos; structure by a small movement of atoms mainly in the direction of the cube diagonal.4&apos;5 However, the probability of filling any particular atom site by a silver or a zinc atom is markedly different in the two structures. The structure can be considered partly ordered but the arrangement of the ordered atoms is completely different from that in the p&apos; structure and transformation from ß&apos; to requires a large fraction of the atoms to change position. It has been shown that the ß&apos; transformation is thermally activated involving normal nucleation and growth processes.5,8 Massalski and Barrett7 have shown that in the Cu-Zn binary the (3 phase can be retained in the ordered state to room temperature over a wide composition range. On deformation a new close-packed phase is produced, the structure varying from fcc to a mixture of fcc + hcp to hcp alone with increasing zinc concentration. It appears that an ordering reaction is necessary to retain the bcc phase to room temperature. In CU-Ga,8 the bcc phase cannot be retained to low temperatures as it transforms by a massive reaction above the ordering temperature of the ß phase. The structure of the massive phase is very similar to that in Cu-Zn, varying from fcc to fcc + hcp to hcp with increasing zinc concentration. Similar structures have also been observed in CU-A1,9 Ag-Cd,10,11 and Ag-Al.12 EXPERIMENTAL The alloys were prepared by melting fine silver (99.99 pct purity) and electrolytic zinc (99.999 pct

Jan 1, 1969

By H. P. Rassbach, E. R. Saunders

MUCH progress has been made in recent years in the theory and practice of making stainless steel. By effective utilization of oxygen for decar-burization and more suitable alloying agents, it has been possible to attain consistent production of very low-carbon stainless steel. In order to facilitate economical production of stainless steels, the Electro Metallurgical Co. has carried out an extended experimental program that has clarified some of the complex interrelations of temperature and composition under decarburizing and reducing conditions. These results&apos;-:&apos; have been founded in large part on small experimental heats, and in order to confirm their validity and significance under commercial conditions, a survey of stainless steel melting practice has been made with the cooperation of stainless steel producers. Conditions required for decarburization and associated oxidation of chromium, manganese, and iron have been fairly well established in relation to the beneficial effect of the highest practicable temperature. The recovery of chromium and manganese from highly oxidized slags by reduction with silicon has been indicated with somewhat less precision and this study has shown significant deviation in large commercial heats from the small experimental heats. In spite of an unsatisfactory degree of accuracy in estimating the conditions affecting reduction of metallic values, it has been possible to calculate a slag weight in reasonably good agreement with the results observed in large heats. While there still is much to be learned about both the qualitative and quantitative aspects of stainless steel melting, this survey has indicated the manner by which the efficiency of the production process may be measured. Oxidation Period In order to establish practices for the recovery of chromium and manganese from the slag the amounts of these metals oxidized should be known. Moreover, since reduction of oxidized chromium and manganese must necessarily be accompanied by similar reduction of iron, knowledge of the total quantity of metallics oxidized is essential. The relations between carbon, chromium, and temperature under oxidizing conditions were developed by Hilty in 1948.&apos; While it had been realized previously that retention of chromium in the metal during carbon oxidation is favored by high temperatures, the Hilty relation provided quantitative information useful for evaluating melting procedures. For example, it was shown that decarburization to moderate carbon levels can be achieved while retaining substantial amounts of chromium. However, in decarburizing to the low-carbon level necessary for producing 0.03 pct maximum carbon stainless steel, very little chromium remains in the bath at the temperatures generally employed. For this reason, Hilty, Healy, and Crafts&apos; later projected an extension of the chromium-carbon relation to the low-chromium region. Although this chromium-carbon-temperature relation defined the composition of a chromium steel bath at the end of the oxidizing period, it did not provide a direct means for estimating the total amount of metallic oxidation occurring during decarburization of a stainless steel heat. This subject was investigated by Crafts and Rassbach³ and, later, by Hilty, Healy, and Crafts" who demonstrated that metallic oxidation is a function of the chromium content of the initial furnace charge, the minimum carbon content attained, and the temperature. It was further demonstrated from data on 1-ton heats that an empirical relationship exists between the ratio of chromium plus manganese to iron in the slag (S) to the corresponding ratio of these components present in the metal bath. The following expression was derived to permit the calculation of the amount of metallics oxidized during decarburization of a given charge: W-2000 (Cr1 + Mn1)-(Cr2 + Mn2) 1 100s/s+1-(Cr3 + Mn2) where W is the pounds of chromium, manganese, and iron oxidized per ton of charge; Cr1, the percentage of chromium in the charge; Mn1, the percentage of manganese in the charge; Cr2, the percentage of chromium in the bath after oxidation; Mn2, the percentage of manganese in the bath after % Cr + % Mn oxidation; and S =%cr+ % Mn/%Fe in the slag after %Fe oxidation. In order to establish whether the slag ratios of commercial heats are consistent with those found in the experimental heats, the slag and metal analyses shown in Table I were evaluated. These data represent samples taken after the oxidation of two 1-ton and seven 15 to 25-ton heats of types 303, 304, and 304L stainless steel made in chromite, acid, and basic hearths. Fig. 1 illustrates that the results for the commercial heats correlate reasonably well with the relationship originally established for experimental 1-ton heats. It will be noted that in the range of metal composition of these heats, the slag values generally lie above the line. As was suggested by

Jan 1, 1954

By P. T. Chiang

Chemical etching methods for the simultaneous revealing of the tellurium or selenium Phase and the chalcogenide grain boundaries of the alloy systems are given. A tellurium eutectic was found Present in zone-melted ingots. Similarly, a selenium monotectic was present in ingots. In general, the second phase (tellurium or seleniumn) occubies three different sites; viz., along the chalcogenide grain boundaries, as inclusions within the chalcogenide grain, and on the undersurface of the ingot. The detection limit for the tellurium phase is about 1 u in width. THERMOELECTRIC materials based on Group V (bismuth, antimony) and Group VI (selenium, tellurium) elements have aroused considerable interest in recent years in the practical application of thermoelectric cooling. In many cases, a small amount of excess tellurium (or selenium) was added to the material to optimize its thermoelectric properties. Then the question immediately arises as to the number of phases present in the resultant alloy. In the binary systems of Bi-Te, Sb-Te, and Bi-Se, the congruent melting compositions have been reported to be non-stoichiometric and are represented by Bi~Te respectively. It is to beexpected and known that Bi2Te3 and SbzTe3 crystallize from the melt with an excess of bismuth and antimony in the lattice and that tellurium forms a eutectic.~&apos; The same could be assumed to take place in the pseudo binary systems of (Bi,Sb)zTe3 and Bi2(Se,Te)3 as well as in the system studiedby puotinen5 and other workers. Likewise, BiaSe3 crystallizes from the melt with an excess of bismuth in the lattice and selenium forms a monotectic.~ Therefore, in practice, alloys solidified from the melt often contain a second phase (tellurium or selenium) in one region or another of the solid mass even without the addition of excess tellurium (or selenium). ~u~~recht&apos; studied the thermoelectric properties of (Bi,Sb)2Te3 alloys with excess tellurium and simultaneous additions of selenium. He mentioned that the materials show two phases because of the considerable excess of tellurium or selenium. However, he did not report as to how the tellurium or selenium phase was identified. It is generally believed that the presence of an excessive amount of tellurium or selenium phase in the alloy would adversely affect its thermoelectric properties and its uniformity. Consequently, there is a need for a simple method for the identification of the tellurium and selenium phase. The quantity of the second phase present is usually too small to be detected either by chemical analysis or by normal X-ray techniques. This investigation was therefore carried out, first, to devise a simple metallographic method for the identification of the tellurium or selenium phase coexisting with the chalcogenides and, second, to determine the distribution and specific location of the tellurium or selenium phase in the ingots. EXPERIMENTAL PROCEDURE The starting materials used for the alloy preparations were 99.999 pct pure bismuth, antimony, and tellurium and 99.997 pct pure selenium. The bismuth and antimony were obtained from Consolidated Mining and Smelting Co. of Canada Ltd., while the selenium and tellurium were obtained from Canadian Copper Refiners Ltd. The tellurium was purified further in the laboratory by zone refining. The elements were pulverized in a stainless-steel pestle and mortar. The amounts for the desired composition were weighed out each time on an analytical balance to make up a 100-g sample. Then the sample was introduced into a Vycor ampule (19 by 150 mm), pumped down to a vacuum of 10"5 Torr for 15 min, and sealed off. The ampule was then heated in a horizontal resistance furnace at 800" to 900°C for about 20 hr. During this period the assembly was rocked back and forth several times to ensure good mixing. At the end of the heating period, the ampule was quenched in cold water and then transferred to the zone-melting apparatus described in a previous publications to grow large-size aligned polycrystals. The background and ring-heater temperatures were adjusted to make the freezing solid-liquid interface slightly convex to the liquid. The recorded temperature gradient in the vicinity of the freezing solid-liquid interface was around 15°C per cm. The ampule was moved horizontally at a speed varying from 0.4 to 2 cm per hr so that the ring heater would cover the whole ingot length from end to end. A single zone-melting pass was used for the Bi-Te, Sb-Te, and Bi-Sb-Te ingots. Two passes in the forward and reverse directions were carried out for the Bi-Se and Bi-Se-Te ingots. Six passes in the forward and reverse directions were performed for the Bi-Sb-Se-Te ingot. The zone-melted ingots were found to contain several large crystals, with their basal planes (0001) approximately parallel to the growth axis. Samples of bismuth and antimony tellurides coated with a layer of tellurium, and bismuth selenide coated with a layer of selenium, were prepared for comparison in phase identification. These coatings were made by dropping a piece of the zone-melted ingot into some molten tellurium or selenium under argon atmosphere and allowing them to cool slowly to room temperature. The metallographic specimens were prepared by

Jan 1, 1969

WELL known member of the Institute, Henry Krumb, survived the Japanese earthquake and has written a most interesting description of his personal experience to a friend in New York, an extended excerpt from which we publish, by permission, below. Not having been written for publication it has increased value as a human document in its vivid description of personal impressions and sensations in the midst of such a catastrophe. The earthquake was the most terrible experience I have ever passed through. We arrived at Miyanoshita, Friday, Aug. 31, about 6 p.m., having left Yokohama about 2:30 that afternoon by automobile. It was a most beautiful ride, although rather warm, but not unusually so, as it has been uncomfortably hot ever since we arrived in Japan. The first part of this automobile trip was along the old highway from Kyoto to Tokyo, which is lined with fine old pine trees. There are 52 villages along this highway and we saw real Japanese country life: naked children, both boys and girls, and men wearing nothing but gee-strings. The country on either side was intensively cultivated, the green rice fields and lotus ponds making a most beautiful sight. The occasional hills were all re-forested with young pines. In places the road runs close to the ocean beaches. The last part of the trip was up a steep mountain road, cut out of the side of the mountain. On one side of the road, in the gulch below, was a roaring river. The road crosses this river several times. Miyanoshita is beautifully located on the side of a mountain about 400 ft. above this river at an altitude of 1400 ft. The grounds of the hotel are laid out in Japanese style, small lakes with fish, waterfalls and dwarf trees making a very pretty sight. On the morning of Sept. 1, after walking around the garden and the hotel, we went to our room and I started to write up a few notes. Mrs. Krumb was reading a guide book. A few minutes before noon she came over to the table where I was writing and said that it was about lunch time. Just at that moment hell broke loose. It was the first earthquake I have ever experienced and I did not immediately realize what was happening. The building was shaking as a mine office might shake when heavy blasting was going on near by. Mrs. Krumb, having experienced many earthquakes, stepped to the open door between our room and the bathroom and called to me to get out from under the chande-lier. The plaster was commencing to fall and a large wardrobe fell over. I then knew what was happening and ran to the win dow. Before I reached it a large chunk of plaster from the ceiling hit me on the head and cut my forehead and nose. Mrs. Krumb ran for the other window just as the marble mantelpiece and the dresser fell. Without any hesitation, she jumped out of the win-dow and I followed suit out of the other. Luckily neither of us sprained an ankle-we had jumped 8 ft. We started to runaway from the building but had not gone more than 25 ft. when a second shock or rather a continuation of the first became so violent and the ground under our feet was trembling so that it was almost impossible to stand up without holding on to a tree. The ground seemed to have become liquid and rocked violently, it seemed to me in a vertical direction. In some later shocks the movement was more horizontal. About this time Mrs. Krumb saw the blood on my face and commenced to break down, but only for a moment: As soon as she saw it was not serious she was all right and during the following days stood the experiences and hardships as well as the best of them:

Jan 11, 1923

By Donald B. Gillies

The fundamentals of human nature don&apos;t change much from generation to generation, or even from century to century. Except for the spur of necessity and the lure of reward and ad venture, few of us would bestir ourselves unduly. The general welfare has little appeal to the average individual. Its promotion comes about mainly as a by-product to individual efforts directed at more personal benefits and satisfactions. In discussing incentives for the mining industry, we really are talking about incentives for people who devote their energies and resources to mining. The vigorous and productive mining industry as we have known it was the product of the varied incentives we have known in the past: the lure of great financial reward if you struck it rich; the thrill of romance and adventure in the search for mineral wealth, usually along the frontiers &apos;of civilization; the satisfaction of developing a great, productive enterprise by the application of skill, courage, and determination in the face of obstacles. Back of the prospector and engineer were other venturesome persons willing to take a flyer with their savings in a grubstake, or in stock in a promising mining venture, hoping for large returns, but reconciled to take a loss and try again with the next opportunity. It is free enterprise-a chance for high profits, but a chance also of total loss-that created the great mining industry of this country and of the world. Free enterprise has given us, in the United States, the greatest productive system in the world, the highest standard of living, the most abundant life. The lure of gold-whether from the ground or merely incidental to the discovery and development of our mineral resources-pushed our frontiers westward across the country and northward into Canada and Alaska far in advance of the staid course of agriculture and commerce. No one guaranteed success to our forebears as they risked life and fortune in developing a new country. Self-reliance was the backbone of our economic and spiritual Progress and achievements. Our neighbors had little time to spare from their own problems. And though there was a willingness among the pioneers to help one another, they didn&apos;t lean too much on one another.

Jan 5, 1950

By W. H. Echols

An oil-emulsion mud, consisting of a mixture of oil-base mud and bentonitic water-base mud, has been used experimentally in drilling 8 of the 35 wells in the Sivells Bend field, Cooke County, Texas. Experience indicates the oil-emulsion mud can be controlled in much the same manner as a water-base mud, and the "drilling" functions of the two types of mud are comparable. The average water-loss for the oil-emulsion mud was 3.8 cu cm per well. When using oil-emulsion mud to drill the last 2000 ft of 7000 ft wells, the mud costs were approximately 2½ times that of water-base mud. There is nothing to indicate well productivities have been affected through the use of oil-emulsion mud. However, drilling time and bit footages were increased and the holes were maintained more closely to bit guage. The apparent advantages gained through the use of oil-emulsion mud in the Sivells Bend field do not appear to justify the increase in mud costs. Introduction until a comparatively few years ago most of the development of drilling mud was directed toward improving the functions of the mud as related to actual drilling operations. The industry has long recognized that one disadvantage of rotary drilling over cable-tool drilling is the possibility of injury to producing zones through the blocking effect resulting from the infiltration of water or mud into the sands. Recognizing this disadvantage, considerable attention has been diverted toward the development of muds that will improve the quality of well com-pletions through the reduction or elimination of water into the sands, but without sacrificing too many of their "drilling" functions and at a cost commensurate with the benefits derived from their use. This phase of mud research has already found practical application, for example, in the development of the Rangely field, Colorado, it appears the use of oil-base mud during drilling-in operations will contribute appreciably toward making this exploitation more profitable. Much of the discussion to follow will be better understood if a brief sketch of the Sivells Bend field is given. The Sivells Bend field, discovered by The Texas Co. in 1944 and still in the process of development, is in a large bend on the Texas side of the Red River about 85 miles north of Dallas. Geologically, the structure is an unsymmetrical anticline, with faulting having contributed to its development. The productive sands are of the Strawn series of Pennsylvanian age, the sands being lenticular in character and varying considerably in development from well to well. At Present there are 35 producing wells in the field, producing from seven different sand lenses. The productive sand lenses vary from 15 to 50 ft in thickness and the individual sands have average permeabilities of from 75 to 375 md. The presently productive sands are encountered at depths of from 6300 to 7300 ft, but testing has indicated that commercial production might be obtained from other sands as high as 5200 ft. Histories of older Strawn

Jan 1, 1948

By W. H. Echols

An oil-emulsion mud, consisting of a mixture of oil-base mud and bentonitic water-base mud, has been used experimentally in drilling 8 of the 35 wells in the Sivells Bend field, Cooke County, Texas. Experience indicates the oil-emulsion mud can be controlled in much the same manner as a water-base mud, and the "drilling" functions of the two types of mud are comparable. The average water-loss for the oil-emulsion mud was 3.8 cu cm per well. When using oil-emulsion mud to drill the last 2000 ft of 7000 ft wells, the mud costs were approximately 2½ times that of water-base mud. There is nothing to indicate well productivities have been affected through the use of oil-emulsion mud. However, drilling time and bit footages were increased and the holes were maintained more closely to bit guage. The apparent advantages gained through the use of oil-emulsion mud in the Sivells Bend field do not appear to justify the increase in mud costs. Introduction until a comparatively few years ago most of the development of drilling mud was directed toward improving the functions of the mud as related to actual drilling operations. The industry has long recognized that one disadvantage of rotary drilling over cable-tool drilling is the possibility of injury to producing zones through the blocking effect resulting from the infiltration of water or mud into the sands. Recognizing this disadvantage, considerable attention has been diverted toward the development of muds that will improve the quality of well com-pletions through the reduction or elimination of water into the sands, but without sacrificing too many of their "drilling" functions and at a cost commensurate with the benefits derived from their use. This phase of mud research has already found practical application, for example, in the development of the Rangely field, Colorado, it appears the use of oil-base mud during drilling-in operations will contribute appreciably toward making this exploitation more profitable. Much of the discussion to follow will be better understood if a brief sketch of the Sivells Bend field is given. The Sivells Bend field, discovered by The Texas Co. in 1944 and still in the process of development, is in a large bend on the Texas side of the Red River about 85 miles north of Dallas. Geologically, the structure is an unsymmetrical anticline, with faulting having contributed to its development. The productive sands are of the Strawn series of Pennsylvanian age, the sands being lenticular in character and varying considerably in development from well to well. At Present there are 35 producing wells in the field, producing from seven different sand lenses. The productive sand lenses vary from 15 to 50 ft in thickness and the individual sands have average permeabilities of from 75 to 375 md. The presently productive sands are encountered at depths of from 6300 to 7300 ft, but testing has indicated that commercial production might be obtained from other sands as high as 5200 ft. Histories of older Strawn

Jan 1, 1948

By RICHARD MAIZE

IN this critical period of our history, the coal industry of the nation, faced with many obstacles, performed its work safely during the first ten months of 1943. Thousands of the younger mine workers were inducted into the armed forces of our country and in many instances their jobs have been filled by others without much if any experience and training. This situation alone would seem to be sufficient to interfere with the safe and orderly operation of the industry but the Government&apos;s demand for a substantial increase in coal tonnage over that produced in normal times introduced a hazard which always accompanies speed, regardless of the skill of the worker.

Jan 1, 1944

THE John Fritz Medal Board of Award, at its regu¬lar annual meeting Oct. 19, awarded its gold medal to Herbert Clark Hoover. Thus ended a process of selection begun a few years ago. The award was tentatively made a year ago by the Board, which is composed of sixteen recent past-presidents of the four national societies of Civil, Mining and Metallurgical, Mechanical, and Electrical Engineers, having together a membership of nearly 60,000. The sixteen members of the Board are: American Society of Civil Engineers : C. E. Grunsky, Robert Ridgway, George S. Davison and John F. Stevens ; American Institute of Mining and Metallurgical Engineers: William Kelly, J. V. W. Reynders, Samuel A. Taylor and E. DeGolyer; American Society of Mechanical Engineers: Fred R. Low, D. S. Jacobus, Dexter S. Kimball and Charles M. Schwab; American Institute of Electrical Engineers: Farley Osgood, M. I. Pupin, C. C. Chesney and Bancroft Gherardi.

Jan 1, 1928

By M. R. Campbell

You have just heard several papers on the classification of coal as this subject appears to the chemist; I shall approach it from the point of view of the geologist who, perforce, has to deal with coal as it occurs in the ground and with the miner of coal who knows certain phases of the physical characteristics of coal better than the scientist can possibly know them. The chemist is familiar with coal as it reaches him in the laboratory, but he seldom has an opportunity to see it in its native condition and to study its physical characteristics and its behavior under varying conditions of weather, transportation and use. He naturally regards the chemical composition of coal as the all-important feature upon which to base a system of classification and he is sometimes inclined to ignore as unscientific any scheme of classification that is based on characteristics other than chemical. The geologist, on the other hand, although he is glad to use the data furnished by the chemist, must depend largely upon the differences that he can see and feel. Classification Understandable to the Layman In the very comprehensive program of examination of the coal fields of the West which the U. S. Geological Survey undertook in 1906, it fell to my lot, as the responsible head of the work, to classify the coals in advance of much knowledge of their chemical composition and in regions where mining had not begun. In this work I was forced to devise some sort of classification that would work practically and that would be understandable to the layman in the field. Much of the classification was based on the work of those who had gone before me, but in the low rank coals of the West the field was unoccupied and I was forced to devise a scheme embracing both chemical and physical characteristics. This scheme has stood the test of actual practical application for several years but it needs revision and the sharpening of the limits between the different ranks. I feel that my experience warrants my saying that physical characteristics must be considered and I have faith to believe that some scheme embodying both can be devised.

Jan 1, 1930

By Charles McElroy White

IT is indeed an honor to have been asked to participate in the program which celebrates the seventy-fifth birthday of the American Institute of Mining and Metallurgical Engineers. This great organization has occupied an important place in the professional and industrial life of this country-of the world. Its members have explored the far reaches of our globe and have played a great part in the discovery, extraction and utilization of the mineral resources upon which our civilization so largely depends. These engineers, together with the restless prospectors, on the one hand, and the scientists, on the other, have literally been the advance scouts of our modern way of life. As such, we owe them a deep and lasting debt of gratitude. May I, therefore, wish many happy returns to the American Institute of Mining and Metallurgical Engineers and express the hope that it may long continue to be of great service, as it has been in the past. The subject assigned to me-Iron Ore and the Steel Industry-is, indeed, important, as one considers the future of our world. I shall give as few figures as possible. Pertinent statistical data are included in the tables in this chapter, which, I think, will prove interesting. Many studies of iron-ore reserves have been -published and are available; hence I shall limit myself mainly to an interpretation of these figures. The statistics data are from standard sources, including the Lake Superior Iron Ore Association, the American Iron and Steel Institute, the United States Bureau of Mines, the United States Geological Survey, the United

Jan 1, 1947

By Miguel Bustamente

In 1890 I mas manager of a mining enterprise in the State of Michoacan. The ores were composed principally of iron pyrites (much decomposed), in a quartz matrix, with native gold in very irregular grains. Some portions, however, carried their metallic value in a matrix of calcite arid siderite. The mill in which the ores were treated consisted of two 800-lb. stamps, two amalgamating-plates, four pans, two automatic washers, two Frue vanners, and the necessary accessories for assaying, retorting and refining gold. The plant, originally erected with American capital, and directed by competent Americans, passed in 1890 into the hands of Mexican owners. On taking charge of the business I found on hand a large amount of ore assaying 35 grammes of gold per metric ton (about 1 oz. Troy per ton of 2000 lbs.); but the company was losing money, and was about to abandon the business. Obviously, the difficulty lay in the treatment of the ore. The extraction of gold scarcely reached one-tenth of the assayvalue ; the loss of mercury was considerable; and high freight; charges excluded the alternative of exporting the ores. This situation naturally suggested that amalgamation was not applicable to these ores, and that a more appropriate method must be adopted. The cyanide- and chlorination-methods had been tried already, without practically satisfactory results. For the first few months I employed a combined system, extracting a part of the gold by direct amalgamation, and cyaniding the concentrates. This saved 32 per cent. of the assay-value, but the cost of milling still exceeded the proceeds. Meanwhile I observed

Jan 1, 1902

By David Baker

IN a paper presented to the American Institute of Mining Engineers, September, 1904, entitled ? Improvements in the Mechanical Charging of the Modern Blast-Furnace,"&apos; I showed the great fault of mechanical charging-devices to be that the materials charged by the dumping of the skip were separated, the coarse materials having high velocity, and the fine, low-thus giving paths of low resistance through the stock in the furnace, which resulted in unequal distribution of the furnace gases, unequal reduction, slips, scaffolds, irregular cutting of the. inwall, " off " iron, and increased fuel-consumption. I showed how this could be prevented by rotary distribution, through which the irregular distribution in one layer charged is compensated by charging the subsequent layers from successively varied positions of the charger, and becomes practically eliminated when the angle between two successive positions is a little more or less than an even fraction of a full circle. Of all the devices then on the market, the nearest approach to the ideal arrangement was found in the Brown distributor, a full description of which was given. The one defect pointed out, however, was the difficulty of maintaining so much mechanism on the top of a blast-furnace. Since the presentation of that paper, I have designed a very simple form of rotary distributor, which may be applied to any form of double-bell charger, retaining the perfect gas-seal, which is so admirably obtained by that construction. In seeking protection for this invention, I found no similar distributor on record in the patent offices of the various countries where application was made; but an application show-

Jul 1, 1906