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By Henry J. Joesting

During the past year and a half, the Territorial Department of Mines in Alaska has conducted a modest experimental program for the purpose of determining the extent to which magnetic and resistivity methods can be used in interior Alaska in connection with prospecting, mining and geological studies. Since little information is available concerning previous work,l,2 and since conditions differ considerably from those in most other regions, it was considered advisable to make a general study of the possibilities and limitations of the two methods, rather than a detailed study of any single problem. Problems One of the most serious handicaps to prospecting and geological study in interior Alaska, especially in the mature regions, is a cover of unconsolidated deposits ranging in thickness from a few feet to several hundred feet. These deposits, some of which are permanently frozen, consist of silt with varying proportions of vegetation and windblown material in the valleys and of residual deposits on the hills.3'4 The problems treated here are caused by the existence of this overburden: I. Location of buried placers. 2. Determination of depth and areal distribution of permanently frozen and of thawed unconsolidated deposits. 3. Location of water-bearing beds under unconsolidated deposits. Instruments and Methods Magnetic and direct-current resistivity methods were used because they are relatively simple, rapid and inexpensive and because generally they are well suited to the study of the problems indicated. The instruments used were a vertical Schmidt-type magnetometer and a direct-current resistivity instrument similar to those used by the Geophysical Branch of the U. S. Geological Survey. For placer surveys with the magnetometer, a sensitivity of about 25 gammas per scale division was found suitable. For resistivity studies of frozen and thawed overburden and of underground water, the Lee partitioning method6 was found to be most generally suitable. In the Lee method a central potential electrode is placed midway between the two potential electrodes of the Wenner four-electrode configuration.7 Nonpolarizable electrodes were made from unglazed porcelain pots about 10 cm. high and 5 cm. in diameter. In order to retard evaporation of the electrolyte the sides of the pots were glazed, inside and out, with clear Duco lacquer. For resistivity work in cold weather, a nonfreezing electrolyte consisting of equal parts of ethylene glycol and a saturated water solution of copper sulphate proved satisfactory. Stainless steel rods of 3/4-in. diameter made excellent current electrodes because their bright finish enabled good ground contacts to be made.

Jan 1, 1946

By Henry J. Joesting

During the past year and a half, the Territorial Department of Mines in Alaska has conducted a modest experimental program for the purpose of determining the extent to which magnetic and resistivity methods can be used in interior Alaska in connection with prospecting, mining and geological studies. Since little information is available concerning previous work,l,2 and since conditions differ considerably from those in most other regions, it was considered advisable to make a general study of the possibilities and limitations of the two methods, rather than a detailed study of any single problem. Problems One of the most serious handicaps to prospecting and geological study in interior Alaska, especially in the mature regions, is a cover of unconsolidated deposits ranging in thickness from a few feet to several hundred feet. These deposits, some of which are permanently frozen, consist of silt with varying proportions of vegetation and windblown material in the valleys and of residual deposits on the hills.3'4 The problems treated here are caused by the existence of this overburden: I. Location of buried placers. 2. Determination of depth and areal distribution of permanently frozen and of thawed unconsolidated deposits. 3. Location of water-bearing beds under unconsolidated deposits. Instruments and Methods Magnetic and direct-current resistivity methods were used because they are relatively simple, rapid and inexpensive and because generally they are well suited to the study of the problems indicated. The instruments used were a vertical Schmidt-type magnetometer and a direct-current resistivity instrument similar to those used by the Geophysical Branch of the U. S. Geological Survey. For placer surveys with the magnetometer, a sensitivity of about 25 gammas per scale division was found suitable. For resistivity studies of frozen and thawed overburden and of underground water, the Lee partitioning method6 was found to be most generally suitable. In the Lee method a central potential electrode is placed midway between the two potential electrodes of the Wenner four-electrode configuration.7 Nonpolarizable electrodes were made from unglazed porcelain pots about 10 cm. high and 5 cm. in diameter. In order to retard evaporation of the electrolyte the sides of the pots were glazed, inside and out, with clear Duco lacquer. For resistivity work in cold weather, a nonfreezing electrolyte consisting of equal parts of ethylene glycol and a saturated water solution of copper sulphate proved satisfactory. Stainless steel rods of 3/4-in. diameter made excellent current electrodes because their bright finish enabled good ground contacts to be made.

Jan 1, 1946

By E. A. Smith, E. R. Parker

METALLURGISTS and engineers have always been interested in the mechanism of high-speed deformation because metals are rapidly deformed in various applications and manufacturing processes. The deformation of metals by impact loads has recently engaged the attention of a number of investigators. Many of their results have not been disclosed but some of the published investigations1-8 have shown that the tensile strength, yield strength and elongation generally increase with increasing strain rate. The investigation reported herein is an attempt to determine the reason for this increase in strength and elongation. Single-crystal copper specimens were broken in tension at impact velocities up to 100 ft. per sec. The distribution of slip bands in the fractured crystals was found to depend upon the strain rate. In the bars broken at high speeds, the slip bands appear to be more numerous. This might account for the higher strength as well as the greater elongation. EXPERIMENTAL PROCEDURE Single crystals of copper (approximately 99.98 per cent) were made in graphite molds by the conventional method of lowering the mold out of the hot zone of a hydrogen furnace at a rate of one inch per hour. Solidification progressed from the bottom upward, forming a single crystal. The crystals were about 0.30 in. in diameter and 4 in. long. They were made into test bars by sliding threaded steel bushings over each end of a crystal and then flowing silver solder between the crystal and the bushing. The inside diameter of the bushings was slightly greater than the diameter of the crystals, to allow space for the silver solder. The bushings were placed so that the gauge length of the crystals was one inch. The assembly is shown in Fig. I, with two views of a fractured crystal. Annealed polycrystalline copper bars of similar shape were machined from solid stock. X-ray measurements were made on all single crystals to determine their orienta¬tions. The results are shown in Fig. 2, where the location of the axis of each specimen is indicated on a standard projection. The bars were broken in a commercial variable-velocity tension im¬pact machine, which has been described in detail elsewhere.7,8 The stress and strain were recorded by means of wire strain gauges and a special commercial oscillo-raph, also described in detail elsewhere.9,10 The equipment and method can be briefly described as follows. The impact machine consists of a motor-driven flywheel containing a two-pronged hammer. This hammer is held retracted in the flywheel

Jan 1, 1944

By G. A. Crowe, W. T. Bishop

WHILE the literature in the United States on general polarographic technique is extensive, very little appears to be directly applicable to the analysis of flotation tailings. For this reason, it seemed worth while to present a few polarographic methods of ore analysis that have been in constant use in the laboratories of the Hercules Experiment Station for the past few years. At the time of our initial investigation of the polarographic method, there was little or no mention of its specific application to flotation tailings. It was therefore necessary for us to establish suitable conditions for the analysis of our flotation tailings and to consider possible interfering constituents. The polarograph, or dropping mercury electrode, method was discovered in 1925 by J. Heyrovsky and M. Shikata,1 of the Charles University, Prague. This method has since received extensive development and the literature contains many articles on the use of the polarograph for the quantitative determination of metals as well as anions, oxygen in solution, and reducible organic compounds. Kolthoff and Lingane,2 by the publication of their book, "Polarography," in 1941 did much to advance the knowledge and use of the polarograph. In chapter 25 of that book, methods for the polarographic analysis of brass, steel and iron products, alloys, and zinc ore are given. Aluminum,3 cadmium,3.4 cobalt,4 copper,3-9 gold,10 iron,3,11 lead, 3,12,13 molybdenum," nickel,4.8,9 tin,15 and zinc3,4,5,7 in ores have been analyzed by the polarograph. However, most of the work on tailing samples has been published in Russian journals and translations are not yet readily available. In this paper we will describe the method that was developed and used in our laboratory for the determination of copper, zinc, and lead in flotation tailings. PRINCIPLE OF THE METHOD The polarograph is an instrument for applying a potential to a mercury pool and a dropping mercury electrode separated by a solution, and for measuring the resultant electrical current. The procedure is essentially a small-scale electrolysis, in which the voltage required to reduce or oxidize the material identifies it qualitatively and the current measures the concentration quantitatively. Different constituents in a sample may often be determined simultaneously provided they reduce at sufficiently different voltages. An example is the determination of copper and zinc in the same solution. The reduction potentials are quite far apart, as shown in Fig. I. The polarographic method is particularly useful in the range of concentration between those normally determined by spectographic and chemical methods. In

Jan 1, 1946

I. PRESIDING OFFICER. At all business meetings of the Institute the President, or, in his absence, the First Vice-President, or, in the absence of both of them, any other Vice-President or Director, chosen by the meeting, shall preside. At all other meetings of the Institute the President, or, in his absence, one of the Vice-presidents, shall preside. If none of these be present the meeting shall elect a Chairman. The President shall do and perform such other duties as may from time to time be assigned to him by resolution of the Board of Directors of the Institute. II. ORDER OF BUSINESS. At each business meeting of the Institute the order of business shall be as follows: 1. Reading of minutes of preceding meeting. 2. Report of the President. 3. Report of the Treasurer. 4. Report of the Secretary. 5. Election of Directors. 6. Reports of Standing Committees. 7. Reports of Special Committees. 8. Special Orders. 9. Miscellaneous business. This order of business may be changed at any meeting, by a vote of a majority of the Members and Associates present. At all sessions of the Institute, other than business meetings, the order of proceedings and the time of adjournment shall rest in the discretion of the presiding officer. III. SECRETARY OF THE INSTITUTE. The Secretary shall keep a record of the proceedings of all the meetings of the Institute. He shall be custodian of the corporate seal, of the minute books and of all the legal documents belonging to the Institute. He shall have charge on behalf of the Institute of all correspondence. He shall notify all Officers and Directors and all members of committees of their election and appointment; shall issue notices of all meetings of the Board, and of the annual and other business meetings of the Institute; and shall, in calling special meetings of the Directors, specify the objects of such meetings. He shall act as clerk at all the meetings of the Board of Directors and at all meetings of the Institute. The Secretary shall be custodian of all technical or scientific papers submitted to the Institute for its consideration and shall have general charge and supervision of the editing and proof-reading of all material published by the Institute, and of the distribution thereof. The Secretary shall be the custodian of all back numbers of the Transactions and other publications of the Institute. There shall be kept under his direction an account

Jan 1, 1925

By A. Cochardt, D. H. Feisel

HE success of the sintered aluminum powder material (SAP)' in raising the maximum useful temperature of aluminum alloys has stimulated effort in investigating similar systems in which the metallic matrixes have higher melting points. Examples of such systems which have been studied are nickel-alumina,2, 3copper-silica,4 copper-alumina,4 titanium-cerium oxide,5 and 80/20 nickel-chromium,8 cobalt,= and molybdenum7 matrixes with various hardeners. Conventional precipitation-hardened high-temperature alloys are often thermally unstable in service. The original fine particles that are responsible for good strength properties grow in size at elevated operating temperatures, a process termed "over-aging." This growth of precipitated particles causes a gradual loss in strength properties. A previous paperb describes the factors that govern the process of overaging, and estimates the time required for overaging of a nickel-alloy matrix dispersion-hardened by various precipitates such as are found in current high-temperature alloys, and by alumina. These calculations indicate that nickel-base alloys hardened with Ni3Al, Tic, or TiN are quite unstable at 1340" F (727°F). Such alloys should overage within a few hours at that temperature. A nickel-base alloy hardened with alumina, on the other hand, should behave differently. It should not overage appreciably within a thousand years. It was further shown8 that the thermal stability of the oxide-hardened alloy is mainly due to the low solubility of oxygen in equilibrium with alumina in the nickel-base matrix. Since the oxygen solubility is small, little oxygen can diffuse, and structural changes require very long times. This paper illustrates the effects of time and temperature on the structural stability of nickel alloy matrixes hardened by dispersions of Ni3A1, Ni3Ti, Tic, and alumina, and of nickel-chromium matrixes hardened by alumina. Hardness measurements and metallography have been used as a measure of structural stability. EXPERIMENTAL PROCEDURE Using the best information from published phase diagrams,'-l4 compositions of the Ni-Al, Ni-Ti, and Ni-Ti-C alloys were determined so as to have 5 vol pct of precipitate at 1350° F(732°C), the temperature selected to illustrate the effect of time on structural stability. Table I lists the chemical compositions of these alloys. Standard laboratory melting and alloying techniques were used in preparing ingots of the F-Series of alloys. The cast ingots, 1 3/4 in. in diam, were forged to 3/8-in. diam rods.

Jan 1, 1960

By H. C. Lukens, E. V. Potter

The volume of hydrogen released from electrolytic manganese at various temperatures and pressures was determined in a previous investigation1 as part of a study to determine the most practical procedure for removing the hydrogen from electrolytic manganese metal. No attempt was made to determine the absolute volume of gas in the metal at any temperature and pressure; the volume of gas released showed only the variation in solubility with temperature and pressure. The results were very similar to those obtained by Sieverts and Moritz.² Both sets of data show a minimum solubility between 500' and 700°C., but they differ in certain respects; on cooling from 500°C., our results showed an increase in solubility of about 7 C.C. as compared with an increase of 34 C.C. per 100 grams shown by Sieverts. Furthermore, the transition temperatures, as indicated by sharp breaks in the solubility curves, did not agree well with Sieverts' data. This information was of secondary importance in the earlier investigations, and the solubility at low temperatures and the transition temperatures were subject to considerable error. Therefore, a subsequent investigation, reported in this paper, was made to measure the absolute solubility at temperatures from room temperature through the melting point and make more accurate observations of the transition temperatures. Apparatus and Method The apparatus and method were essentially the same as those described in the previous work,' as shown in Fig. I. At high temperatures, the small tube containing the thermocouple in the sample container A frequently broke off, so for some of this work the thermocouple was placed outside the sample container and protected by a quartz tube of about the same wall thickness as the sample container. No significant difference was found in the transition temperatures obtained in the two ways. The automatic temperature controller was used in these tests in the regions where there was little change in solubility with temperature. In the neighborhood of the transition points a continuously variable autotransformer was used instead of the automatic controller, and the power input to the furnace was adjusted so that the temperature increased or decreased at a very slow, uniform rate through the transition range. This procedure was followed because the temperature oscillations produced by the controller were too great compared with the transition range, and the transi- . tion points determined under such conditions were less accurate. Absolute Solubility Procedure ad Results The absolute solubility of hydrogen in manganese could be determined most

Jan 1, 1947

By E. V. Potter, H. C. Lukens

The volume of hydrogen released from electrolytic manganese at various temperatures and pressures was determined in a previous investigation1 as part of a study to determine the most practical procedure for removing the hydrogen from electrolytic manganese metal. No attempt was made to determine the absolute volume of gas in the metal at any temperature and pressure; the volume of gas released showed only the variation in solubility with temperature and pressure. The results were very similar to those obtained by Sieverts and Moritz.² Both sets of data show a minimum solubility between 500' and 700°C., but they differ in certain respects; on cooling from 500°C., our results showed an increase in solubility of about 7 C.C. as compared with an increase of 34 C.C. per 100 grams shown by Sieverts. Furthermore, the transition temperatures, as indicated by sharp breaks in the solubility curves, did not agree well with Sieverts' data. This information was of secondary importance in the earlier investigations, and the solubility at low temperatures and the transition temperatures were subject to considerable error. Therefore, a subsequent investigation, reported in this paper, was made to measure the absolute solubility at temperatures from room temperature through the melting point and make more accurate observations of the transition temperatures. Apparatus and Method The apparatus and method were essentially the same as those described in the previous work,' as shown in Fig. I. At high temperatures, the small tube containing the thermocouple in the sample container A frequently broke off, so for some of this work the thermocouple was placed outside the sample container and protected by a quartz tube of about the same wall thickness as the sample container. No significant difference was found in the transition temperatures obtained in the two ways. The automatic temperature controller was used in these tests in the regions where there was little change in solubility with temperature. In the neighborhood of the transition points a continuously variable autotransformer was used instead of the automatic controller, and the power input to the furnace was adjusted so that the temperature increased or decreased at a very slow, uniform rate through the transition range. This procedure was followed because the temperature oscillations produced by the controller were too great compared with the transition range, and the transi- . tion points determined under such conditions were less accurate. Absolute Solubility Procedure ad Results The absolute solubility of hydrogen in manganese could be determined most

Jan 1, 1947

By J. R. Long, T. R. Graham, R. S. Dean

ALTHOUGH considerable information has been published concerning manganese additions to the aluminum bronzes, these data refer principally to the two-phase alloys containing 8 to 11 pct aluminum, with some incidental information on the single-phase alpha solid solution alloys. Strauss1 gives an excellent review of the literature on aluminum bronzes up to 1927 and a bulletin2 of the Copper Development Association brings the bibliography up to 1938. The most extensive work on manganese addition is that of Rosenhain and Lantsberry,3 who investigated alloys ranging up to 10 pct aluminum and up to 10 pct manganese, and presented data on the physical properties of sand-cast, chill-cast, and several wrought alloys. The greater portion of the work, however, concerns alloys ranging from 7 to 10 pct aluminum in the cast condition and sheds little light on the properties of wrought single-phase alloys. Corson4 notes that alloys containing 10 pct manganese and 4 pct aluminum are not hardenable by heat-treatment, while one with 15 pct manganese and 5 pct aluminum can be hardened, but he gives no tensile data on it. In fact, no systematic study of the properties of single-phase wrought alloys containing substantial amounts of manganese has been reported. It should also be noted that most of the investigators worked with alloys containing significant amounts of iron and silicon, and that these impurities, whether intentionally added or accrued from the raw materials used in the preparation of the alloys, may be expected to have a direct bearing on the resultant properties. In the work on alloys made with electrolytic manganese, the Bureau of Mines has undertaken an investigation of the copper-manganese-aluminum system for the purpose of establishing the constitution and properties of high-purity alloys. In a recent paper5 the authors reported a metallographic investigation of the alpha solid solution area and the adjoining fields of the copper-manganese-aluminum system up to 50 pct manganese. This study established the alpha-phase boundaries at 50° temperature levels from 400° to 850°C. It was found that the addition of manganese to copper-aluminum alloys decreases the solubility of aluminum in the alpha phase (Fig I), curving the boundary toward the copper-manganese base line. The greatest change occurs in the first 20 to 25 pct manganese, which decreases the solubility of aluminum to approximately 4 pct. With larger amounts of manganese the alpha boundary tends to parallel the copper-manganese binary. At 1300°F and higher,

Jan 1, 1947

By Henry R. Joesting

DURING the past year and a half, the Territorial Department of Mines in Alaska has conducted a modest experimental program for the purpose of determining the extent to which magnetic and resistivity methods can be used in interior Alaska in connection with prospecting, mining and geological studies. Since little information is available concerning previous work,1,2 and since conditions differ considerably from those in most other regions, it was considered advisable to make a general study of the possibilities and limitations of the two methods, rather than a detailed study of any single problem. PROBLEMS One of the most serious handicaps to prospecting and geological study in interior Alaska, especially in the mature regions, is a cover of unconsolidated deposits ranging in thickness from a few feet to several hundred feet. These deposits, some of which are permanently frozen, consist of silt with varying proportions of vegetation and windblown material in the valleys and of residual deposits on the hills.3,4 The problems treated here are caused by the existence of this overburden: I. Location of buried placers. 2. Determination of depth and areal distribution of permanently frozen and of thawed unconsolidated deposits. 3. Location of water-bearing beds under unconsolidated deposits. INSTRUMENTS AND METHODS Magnetic and direct-current resistivity methods were used because they are relatively simple, rapid and inexpensive and because generally they are well suited to the study of the problems indicated. The instruments used were a vertical Schmidt-type magnetometer and a direct-current resistivity instrument similar to those used by the Geophysical Branch of the U. S. Geological Survey.5 For placer surveys with the magnetometer, a sensitivity of about 25 gammas per scale division was found suitable. For resistivity studies of frozen and thawed overburden and of underground water, the Lee partitioning method6 was found to be most generally suitable. In the Lee method a central potential electrode is placed midway between the two potential electrodes of the Wenner four-electrode configuration.7 Nonpolarizable electrodes were made from unglazed porcelain pots about 10 cm. high and 5 cm. in diameter. In order to retard evaporation of the electrolyte the sides of the pots were glazed, inside and out, with clear Duco lacquer. For resistivity work in cold weather, a nonfreezing electrolyte consisting of equal parts of ethylene glycol and a saturated water solution of copper sulphate proved satisfactory. Stainless steel rods of 3/4-in. diameter made excellent current electrodes because their bright finish enabled good ground contacts to be made.

Jan 1, 1941

By F. J. Meringer, C. W. MacGregor

Various investigations have been carried out to determine the effects of cold-rolling on the common physical properties as represented by the yield strength, tensile strength, percentage of elongation and ordinary reduction of area. Very little information is available in the literature with reference to the effects of cold-rolling on the true stress-strain properties. Since the ordinary physical properties base both the stresses and the strains on the original dimensions of the test piece, which are greatly changed during the test, they are essentially empirical values and do not represent physically either true stresses or true strains. Consequently, they do not give an accurate picture of the effects of different conditions, both mechanical and metallurgical, on the strength and ductility of the material. It is not, however, the purpose of this paper to review the various advantages accruing from the use of true stress and true strain values, since these have been shown elsewhere,1-l2 but to utilize them in representing the various effects considered. The true stress S and true strain (e = q') values mentioned above for the tension test are defined by1 S =1/A and where P, A, Ao are the axial load, the instantaneous area and the original area of cross section, respectively. From simultaneous readings of the axial load and the dimension or dimensions determining the instantaneous area of cross section, the true stress-strain curve is constructed by using the relations given in Eq. I. It is then the object of this paper to discuss the general effects of cold-rolling on the true stress and strain values for a low-carbon steel together with the effects of age-hardening and directionality on these properties. Preliminary Investigations The material considered throughout the paper is a low-carbon steel of the following chemical analysis: C, 0.19 per cent; S, 0.118; P, 0.092; Mn, 0.85; Si, 0.01. The stock was received in bars, 7 by 3/4 in., and was first annealed for one hour at 1650°F. followed by a furnace cool. Photomicrographs of this material showed considerable directionality even in the annealed condition. In view of the possible effects of the nonhomogeneity and directionality in this material, it was considered important to investigate their influence on the true stress-strain diagrams. In addition, the effect of strain-aging in this steel was also made the subject of a preliminary study. Effect of Aging on True Stress-strain Properties Since a certain time element would elapse between the cold-rolling operation and the final tension tests, it was determined to investigate the aging character-

Jan 1, 1945

By W. T. Bishop, G. A. Crowe

While the literature in the United States on general polarographic technique is extensive, very little appears to be directly applicable to the analysis of flotation tailings. For this reason, it seemed worth while to present a few polarographic methods of ore analysis that have been in constant use in the laboratories of the Hercules Experiment Station for the past few years. At the time of our initial investigation of the polarographic method, there was little or no mention of its specific application to flotation tailings. It was therefore necessary for us to establish suitable conditions for the analysis of our flotation tailings and to consider possible interfering constituents. The polarograph, or dropping mercury electrode, method was discovered in 1925 by J. Heyrovsky and M. Shikata,1 of the Charles University, Prague. This method has since received extensive development and the literature contains many articles on the use of the polarograph for the quantitative determination of metals as well as anions, oxygen in solution, and reducible organic compounds. Kolthoff and Lingane,² by the publication of their book, "Polarography," in 1941 did much to advance the knowledge and use of the polarograph. In chapter 25 of that book, methods for the polarographic analysis of brass, steel and iron products, alloys, and zinc ore are given. Aluminum,³ cadmium,³,4 cobalt,4 cop-per,³-9 gold,10 iron,3,11 lead,³,l2,l³ molybdenum,14 nickel,4,8,9 tin," and zinc³,4,5,7 in ores have been analyzed by the polarograph. However, most of the work on tailing samples has been published in Russian journals and translations are not yet readily available. In this paper we will describe the method that was developed and used in our laboratory for the determination of copper, zinc, and lead in flotation tailings. Principle OF the Method The polarograph is an instrument for applying a potential to a mercury pool and a dropping mercury electrode separated by a solution, and for measuring the resultant electrical current. The procedure is essentially a small-scale electrolysis, in which the voltage required to reduce or oxidize the material identifies it qualitatively and the current measures the concentration quantitatively. Different constituents in a sample may often be determined simultaneously provided they reduce at sufficiently different voltages. An example is the determination of copper and zinc in the same solution. The reduction potentials are quite far apart, as shown in Fig. I. The polarographic method is particularly useful in the range of concentration between those normally determined by spectographic and chemical methods. In

Jan 1, 1947

By G. A. Crowe, W. T. Bishop

While the literature in the United States on general polarographic technique is extensive, very little appears to be directly applicable to the analysis of flotation tailings. For this reason, it seemed worth while to present a few polarographic methods of ore analysis that have been in constant use in the laboratories of the Hercules Experiment Station for the past few years. At the time of our initial investigation of the polarographic method, there was little or no mention of its specific application to flotation tailings. It was therefore necessary for us to establish suitable conditions for the analysis of our flotation tailings and to consider possible interfering constituents. The polarograph, or dropping mercury electrode, method was discovered in 1925 by J. Heyrovsky and M. Shikata,1 of the Charles University, Prague. This method has since received extensive development and the literature contains many articles on the use of the polarograph for the quantitative determination of metals as well as anions, oxygen in solution, and reducible organic compounds. Kolthoff and Lingane,² by the publication of their book, "Polarography," in 1941 did much to advance the knowledge and use of the polarograph. In chapter 25 of that book, methods for the polarographic analysis of brass, steel and iron products, alloys, and zinc ore are given. Aluminum,³ cadmium,³,4 cobalt,4 cop-per,³-9 gold,10 iron,3,11 lead,³,l2,l³ molybdenum,14 nickel,4,8,9 tin," and zinc³,4,5,7 in ores have been analyzed by the polarograph. However, most of the work on tailing samples has been published in Russian journals and translations are not yet readily available. In this paper we will describe the method that was developed and used in our laboratory for the determination of copper, zinc, and lead in flotation tailings. Principle OF the Method The polarograph is an instrument for applying a potential to a mercury pool and a dropping mercury electrode separated by a solution, and for measuring the resultant electrical current. The procedure is essentially a small-scale electrolysis, in which the voltage required to reduce or oxidize the material identifies it qualitatively and the current measures the concentration quantitatively. Different constituents in a sample may often be determined simultaneously provided they reduce at sufficiently different voltages. An example is the determination of copper and zinc in the same solution. The reduction potentials are quite far apart, as shown in Fig. I. The polarographic method is particularly useful in the range of concentration between those normally determined by spectographic and chemical methods. In

Jan 1, 1947

I. PRESIDING OFFICER. At all business meetings of the Institute the President, or, in his absence, the First Vice-President, or, in the absence of both of them, any other Vice-President or Director, chosen by the meeting, Shall preside. At all other meetings of the Institute the President, or, in his absence, one of the Vice-presidents, Shall preside. If none of these be present the meeting Shall elect a Chairman. The President Shall do and perform Such other duties as may from time to time be assigned to him by resolution of the Board of Directors of the Institute. IL ORDER OF BUSINESS. At each business meeting of the Institute the order of business Shall be as follows: 1. Reading of minutes of preceding meeting. 2. Report of the President. 3. Report of the Treasurer. 4. Report of the Secretary. 5. Election of Directors. 6. Reports of Standing Committees. 7. Reports of Special Committees. 8. Special Orders. 9. Miscellaneous business. This order of business may be changed at any meeting, by a vote of a majority of the Members and Associates present. At all sessions of the Institute, other than business meetings, the order of proceedings and the time of adjournment Shall rest in the discretion of the presiding officer. III. SECRETARY OF THE INSTITUTE. The Secretary Shall keep a record of the proceedings of all the meetings of the Institute. He Shall be custodian of the corporate Seal, of the minute books and of all the legal documents belonging to the Institute. He Shall have charge on behalf of the Institute of all correspondence. He Shall notify all Officers and Directors and all members of committees of their election and appointment; Shall issue notices of all meetings of the Board, and of the annual and other business meetings of the Institute; and Shall, in calling Special meetings of the Directors, Specify the objects of Such meetings. He Shall act as clerk at all the meetings of the Board of Directors and at all meetings of the Institute. The Secretary Shall be custodian of all technical or Scientific papers Submitted to the Institute for its consideration and Shall have general charge and supervision of the editing and proof-reading of all material published by the Institute, and. of the distribution thereof. The Secretary shall be the custodian of all back numbers of the Transactions and other publications of the Institute. There Shall be kept under his direction an account

Jan 1, 1925

By Alfred V. de Forest

We are now assembled in this hall for the eighteenth lecture in honor of the memory of our greatest American metallurgist, Henry Marion Howe. Many of his most intimate contemporaries, led, as was fitting, by Professor Sauveur, have described his vital accomplishments in three fields: as a leader in technical industrial development; in theoretical research; and finally as a teacher and source of inspiration for nearly two generations of students. In 1914 Professor Howe had retired from active teaching, but maintained his laboratory at Columbia University under the care of Arthur G. Levy, with whom he published many of the papers that later were incorporated into his last book, " The Metallography of Steel and Cast Iron." My position at the time was that of personal assistant to Professor Campbell—no pay, no duties, but the great privilege of preparing specimens, taking pictures and attending to some of the current consulting work. Whenever possible, I visited Howe's laboratory to chat with Levy and gather ideas about the wonderful field of metallography—in which I was a rank amateur, rescued by the quiet enthusiasm of Donald Smith of Princeton from an instructorship in civil engineering. Levy let me act as a fly on the wall during the Professor's occasional visits. Busy as he was, Professor Howe took the time and trouble to encourage my interest, as he had done for hun- dreds of others. He told me how he went about gathering his own information speculating as to causes, considering experiments, and verifying his conclusions. I ventured to mention some tests I had run on the irregular stretching of wires of different metals. He read the small volume I had prepared of ill-assorted facts and fancies and remarked: "Nobody cares for your theories or the history of your tests. Describe what you found as briefly as possible and perhaps I can help you to publish." Curiously enough, among my discards were some autographically recorded load-versus-electrical-resistance measurements. Taken with inadequate knowledge and equipment, these curves did not reproduce consistently, but if the relationship between strain and resistance had then been explored, the latest type of strain gauge might have been in useful service for the past 25 years. Professor Howe was a gifted teacher, perhaps because he was primarily an ardent and assiduous student. His own eagerness to learn and his willingness to revise and extend his opinions constantly encouraged those of his environment to be diligent and painstaking in the pursuit of knowledge. In honoring his memory, I also wish to bring to mind the kindly, humorous and quiet Levy, and join his name again, as it was for too brief a space in the past, with that of many-sided Henry Marion Howe. Factors oF Impact Strength The subject chosen for the Howe Memorial Lecture by Dr. Gillett last year

Jan 1, 1941

By Alfred V. de Forest

We are now assembled in this hall for the eighteenth lecture in honor of the memory of our greatest American metallurgist, Henry Marion Howe. Many of his most intimate contemporaries, led, as was fitting, by Professor Sauveur, have described his vital accomplishments in three fields: as a leader in technical industrial development; in theoretical research; and finally as a teacher and source of inspiration for nearly two generations of students. In 1914 Professor Howe had retired from active teaching, but maintained his laboratory at Columbia University under the care of Arthur G. Levy, with whom he published many of the papers that later were incorporated into his last book, " The Metallography of Steel and Cast Iron." My position at the time was that of personal assistant to Professor Campbell—no pay, no duties, but the great privilege of preparing specimens, taking pictures and attending to some of the current consulting work. Whenever possible, I visited Howe's laboratory to chat with Levy and gather ideas about the wonderful field of metallography—in which I was a rank amateur, rescued by the quiet enthusiasm of Donald Smith of Princeton from an instructorship in civil engineering. Levy let me act as a fly on the wall during the Professor's occasional visits. Busy as he was, Professor Howe took the time and trouble to encourage my interest, as he had done for hun- dreds of others. He told me how he went about gathering his own information speculating as to causes, considering experiments, and verifying his conclusions. I ventured to mention some tests I had run on the irregular stretching of wires of different metals. He read the small volume I had prepared of ill-assorted facts and fancies and remarked: "Nobody cares for your theories or the history of your tests. Describe what you found as briefly as possible and perhaps I can help you to publish." Curiously enough, among my discards were some autographically recorded load-versus-electrical-resistance measurements. Taken with inadequate knowledge and equipment, these curves did not reproduce consistently, but if the relationship between strain and resistance had then been explored, the latest type of strain gauge might have been in useful service for the past 25 years. Professor Howe was a gifted teacher, perhaps because he was primarily an ardent and assiduous student. His own eagerness to learn and his willingness to revise and extend his opinions constantly encouraged those of his environment to be diligent and painstaking in the pursuit of knowledge. In honoring his memory, I also wish to bring to mind the kindly, humorous and quiet Levy, and join his name again, as it was for too brief a space in the past, with that of many-sided Henry Marion Howe. Factors oF Impact Strength The subject chosen for the Howe Memorial Lecture by Dr. Gillett last year

Jan 1, 1941

By F. J. Mehringer, C. W. MacGregor

VARIOUS investigations have been carried out to determine the effects of cold-rolling on the common physical properties as represented by the yield strength, tensile strength, percentage of elongation and ordinary reduction of area. Very little information is available in the literature with reference to the effects of cold-rolling on the true stress-strain properties. Since the ordinary physical properties base both the stresses and the strains on the original dimensions of the test piece, which are greatly changed during the test, they are essentially empirical values and do not represent physically either true stresses or true strains. Consequently, they do not give an accurate picture of the effects of different conditions, both mechanical and metallurgical, on the strength and ductility of the material. It is not, however, the purpose of this paper to review the various advantages accruing from the use of true stress and true strain values, since these have been shown elsewhere,1-12 but to utilize them in representing the various effects considered. The true stress S and true strain (e = q') values mentioned above for the tension test are defined by1 [ ] where P, A, Ao are the axial load, the instantaneous area and the original area of cross section, respectively. From simultaneous readings of the axial load and the dimension or dimensions determining the instantaneous area of cross section, the true stress-strain curve is constructed by using the relations given in Eq. I. It is then the object of this paper to discuss the general effects of cold-rolling on the true stress and strain values for a low-carbon steel together with the effects of age-hardening and directionality on these properties. PRELIMINARY INVESTIGATIONS The material considered throughout the paper is a low-carbon steel of the following chemical analysis: C, 019 per cent; S, 0. 118; P, 0.092; Mn, 0.85; Si, 0.01. The stock was received in bars, 7 by 3/4 in., and was first annealed for one hour at 1650°F. followed by a furnace cool. Photomicrographs of this material showed considerable directionality even in the annealed condition. In view of the possible effects of the nonhomogeneity and directionality in this material, it was considered important to investigate their influence on the true stress-strain diagrams. In addition, the effect of strain-aging in this steel was also made the subject of a preliminary study. Elect of Aging on True Stress-strain Properties Since a certain time element would elapse between the cold-rolling operation and the final tension tests, it was determined to investigate the aging character-

Jan 1, 1945

By T. D. Guldem, J. L. Kaae

ALLOYS with nominal composition of 45-Fe 35-Ni 20-Cr, ASTM-B-163, known under the commercial names of Incoloy 800 and Sanicro 31 (Alloy 800), are often employed at elevated temperatures for extended periods. Therefore, knowledge of the aging behavior of these alloys is of considerable importance. Significant decreases in ductility and increases in yield strength have been observed in the 45-Fe 35-Ni 20-Cr alloys containing about 0.4 pct Ti and 0.4 pct A1 after long-term aging at 540" to 700"~."~ However, no direct evidence has been presented for precipitation phenomena that might result in such changes. Strengthening effects have been attributed to the effects of local or-dering.3 Since y' precipitation (Ni3A1, Ti) is known to occur in similar alloys which contain more titanium and aluminum,4-7 it was decided to explore the possibility that y' might precipitate in these alloys and might be responsible for the changes in mechanical properties on aging. This note reports some observations of two distict types of matrix precipitates made by means of transmission electron microscopy, in a 45-Fe 35-Ni 20-Cr alloy containing 0.31 pct Ti and 0.4 pct Al. The steel used in this investigation was obtained from the Sand-vik Steel Works; it is designated Sanicro-31 (Alloy 800). The chemical composition of the alloy is given in Table I. Aging of solution-treated material at 700" and 800°C for 130 and 100 hr, respectively, produced the matrix precipitates shown in Figs. l(a) and l(b). It is apparent from these micrographs that the precipitate particles occurred in the form of thin square plates parallel to the matrix cube planes. Extraction replication and selected-area electron diffraction showed that the precipitates were M23C6. Coherency strains, consistent with the semicoherent nature of small M23C6 precipitates,' were evident for certain imaging conditions. In addition to matrix precipitation, preferential precipitation of M23C6 on dislocations was common, as has been reported previously for austenitic stainless steels.'" Specimens aged for longer times (-300 hr) at 700°C exhibited a different type of coherent matrix precipitate in addition to the M23C6. An example is shown in Figs. 2(a) and 2(b). In addition to the few large M23C6 precipitates, small precipitates exhibiting strain contrastl0,ll are present. The "line of no contrast" of the strain field of a given precipitate lies along differ-

Jan 1, 1970

By R. S. Christie

Reservoir pressure is the pressure at which a fluid is held in a state of equilibrium in a porous stratum. This pressure may be a result of the genesis of oil or gas and its subsequent migration into and through an adjacent porous stratum, or of hydraulic head. Reservoir pressure is an indication of the potential energy contained in the reservoir, and when it is known the engineer is in a position to use it to advantage in recovering and lifting the oil. It is important to know the pressures in any type of reservoir, but this knowledge is probably of greater value in a limestone reservoir, as at Hobbs, where producing rates or conditions may be more sensitive to changes in pressures. The Hobbs field is in east central Lea County, New Mexico. The discovery well was completed by the Midwest Refining C I. in 1928, but intensive development did not begin until after the completion by the Humble Oil and Refining Co. of No. 1-A Bowers in February, 1930. There are 143 producing wells on approximately 5500 acres. The field has not been defined to the northwest, but a projection of structural contours indicates that the productive area ultimately may cover 7500 acres. The producing horizon is the White or Crystalline lime of Permian age. The top of the lime is found at an average depth of 4000 ft. and the wells penetrate it an average distance of 200 ft. The main pay zone is an oolitic stratum about 25 ft. below the top, and varies from 2 to 15 ft. in thickness. Other porous or cavernous strata are found lower in the lime but have little saturation. The initial production varied from 100 to 25,000 bbl. per day, depending perhaps to some extent on the structural location but chiefly on the porosity of the pay. The initial gas-oil ratio varied from 325 to 16,000 cu. ft. per barrel. In wells where the top of the White lime was found below 350 ft. below sea level (Fig. 1)) the gas-oil ratio was usually less than 1500 cu. ft. per barrel, while in wells higher than 350 ft. below sea level, the ratio was usually above 2000 cu. ft. per barrel. The water table has been determined at about 620 ft. below sea level, by three wells on the west side of the field. With few exceptions, the wells have been completed with 7-in. casing cemented

Jan 1, 1932

By Alfred V. de Forest

WE are now assembled in this hall for the eighteenth lecture in honor of the memory of our greatest American metallurgist, Henry Marion Howe. Many of his most intimate contemporaries, led, as was fitting, by Professor Sauveur, have described his vital accomplishments in three fields: as a leader in technical industrial development; in theoretical research; and finally as a teacher and source of inspiration for nearly two generations of students. In 1914 Professor Howe had retired from active teaching, but maintained his laboratory at Columbia University under the care of Arthur G. Levy, with whom he published many of the papers that later were incorporated into his last book, "The Metallography of Steel and Cast Iron." My position at the time was that of personal assistant to Professor Campbell-no pay, no duties, but the great privilege of preparing specimens, taking pictures and attending to some of the current consulting work. Whenever possible, I visited Howe's laboratory to chat with Levy and gather ideas about the wonderful field of metallography-in which I was a rank amateur, rescued by the quiet enthusiasm of Donald Smith of Princeton from an instructorship in civil engineering. Levy let me act as a fly on the wall during the Professor's occasional visits. Busy as he was, Professor Howe took the time and trouble to encourage my interest, as he had done for hundreds of others. He told me how he went about gathering his own information speculating as to causes, considering experiments, and verifying his conclusions. I ventured to mention some tests I had run on the irregular stretching of wires of different metals. He read the small volume I had prepared of ill-assorted facts and fancies and remarked: "Nobody cares for your theories or the history of your tests. Describe what you found as briefly as possible and perhaps I can help you to publish." Curiously enough, among my discards were some autographically recorded load-versus-electrical-resistance measurements. Taken with inadequate knowledge and equipment, these curves did not reproduce consistently, but if the relationship between strain and resistance had then been explored, the latest type of strain gauge might have been in useful service for the past 25 years. Professor Howe was a gifted teacher, perhaps because he was primarily an ardent and assiduous student. His own eagerness to learn and his willingness to revise and extend his opinions constantly encouraged those of his environment to be diligent and painstaking in the pursuit of knowledge. In honoring his memory, I also wish to bring to mind the kindly, humorous and quiet Levy, and join his name again, as it was for too brief a space in the past, with that of many-sided Henry Marion Howe. FACTORS OF IMPACT STRENGTH The subject chosen for the Howe Memorial Lecture by Dr. Gillett last year

Jan 1, 1941