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Volume 24, Issue 7
Displaying 1-19 of 19 articles from this issue
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Shirô Watanabe1960 Volume 24 Issue 7 Pages 401-405
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSNo reliable method has been developed for the determination of iron in the state of ferrous oxide coexisting with ferric oxide and trivalent and tetravalent manganese oxides in an ore sample. The ordinary method of dissolving a sample with hydrochloric or sulfuric acid is not suitable to determine the ferrous iron of manganese ore, either, because of the oxidation of ferrous oxide by chlorine or oxygen, produced during the sample solution. After some experiments, the recommended procedure for the above purpose was decided as follows: A 0.2 g sample is dissolved in a mixed solution of 10 mL of 20% sodium sulfite and 30 mL of (1+1) phosphoric acid, passing carbon dioxide through it on a boiling water bath, then the solution is transfered to a heater to decompose the excess of sodium sulfite by approximately 10 minutes boiling. The flask is cooled and the ferrous iron in the solution is titrated with N/50 ammonium metavanadate solution with diphenyl amine as an indicator. The ferric oxide is given, by subtracting the ferrous oxide thus obtained from the total iron of the sample, previously determined by means of the stannous chloride reduction-permanganate titration method.View full abstractDownload PDF (742K) -
Shirô Watanabe1960 Volume 24 Issue 7 Pages 405-409
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe methods for the determination of the available oxygen in manganese and reduced manganese ores with sodium oxalate and with ferrous sulfate were examined. The result of analysis of pure synthesized manganese dioxide indicated that the sodium oxalate method gave positive errors, because sodium oxalate was decomposed by manganous manganese and air, but gave a good result when correction was made for the amount of the decomposed salt. The result of ferrous sulfate method was in good agreement with theoretical values. Although both the methods gave negative errors when the samples used contained ferrous compounds, reasonable results could be gained if corrections were made for the ferrous iron in the sample which had been preliminary determined by means of phosphoric acid solution containing sodium sulfite, as reported in Part 5.View full abstractDownload PDF (676K) -
Shiro Watanabe1960 Volume 24 Issue 7 Pages 409-413
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe methods for the determination of the trivalent and tetravalent manganese oxide in manganese and reduced manganese ores were examined. With acetylacetone the trivalent manganese ion forms a stable complex without any oxidizing action on acidified potassium iodide. In the presence of acetylacetone, manganese-tetrachloride, the resultant product of an ore sample dissolved in hydrochloric acid, loses chlorine and forms stable trichloride. The chlorine thus liberated chlorinates the acetylacetone, liberating iodine in an acid medium, if potassium iodide is present. Thus, by estimating the iodine liberated it is possible to determine the tetravalent manganese oxide in the presence of the trivalent manganese oxide. Although the method gives a positive error when the acetylacetone complex oxidizes potasium iodide if the acidity is high in a sample containing ferric iron, reasonable results can be gained if potassium iodide is added after the ferric iron has been reduced with stannous chloride. Hence the trivalent manganese oxide in an ore sample can be calculated by subtracting the value of tetravalent manganese, obtained as above, from the sum of trivalent and tetravalent manganese equivalent to the available oxygen obtained with ferrous sulfate method, as reported in Part 6.View full abstractDownload PDF (677K) -
Tadashi Yanagihara, Hirozo Kimura, Minoru Chiba1960 Volume 24 Issue 7 Pages 413-417
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe contamination of platinum with nuclear fission products and its decontamination has been studied. Platinum plates were contaminated by soaking in a solution of fission products. The contamination increased with increase of the soaking time, and was saturated in about 3 hr. It was confirmed by the methods of autoradiography, electron microscopy and optical microscopy that the contamination was markedly affected by the surface condition of platinum. The results of the experiments of the decontamination are summarized as follows: (1) Decontamination with tap water: A sample soaked in the solution of fission products only for a short time was easy to decontaminate and the amount of the residual contamination reached equilibrium more rapidly than in the long-soaked sample. (2) Decontamination with acids: HCl, HNO3, H2SO4, H3PO4 and HF were tried. The effect of temperature on the decontamination was very significant. The decontamination with HCl of high temperature was more effective than with the other acids. (3) Decontamination with fused salts: The decontamination with fused KHSO4 was more effective than with the acids and other fused salts. Only one immersion of the contaminated platinum plate into fused KHSO4 could remove 99.4% of the contamination. Finally, it may be confirmed that the degree of the contamination of platinum with fission products is very low and it is easy to decontaminate it with the decontaminating agents such as HCl and KHSO4.View full abstractDownload PDF (753K) -
Tasaburo Nishioka, Yukio Yasukuni1960 Volume 24 Issue 7 Pages 417-421
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn diesem Bericht wurde die Beziehung zwischen Gefüge und Vickershärte in Längsschnitt sowie dem Verhältnis (HL⁄HQ) der Härte, die von jeder Diagonale in Längs- und Querrichtung des Eindruckes berechnet wurde, in verschiedentlich wärmebehandeltem und gezogenem Stahldraht aufgeklärt. Nämlich grösser wird die Zunahme der Härte durch Ziehen nach dem 1.Zug mit abnehmendem C% und Wärmebehandelfestigkeit und nach mehren Zügen mit zunehmendem C% und Festigkeit. HL⁄HQ bleibt mit steigender Ziehverformung anfangs unter 1 und dann steigt über 1 langsam auf,aber in weiteren Verlauf des Ziehens bleibt unveränderlich. Und mit steigendem C% nimmt HL⁄HQ unter 90% Querschnittsabnahme zu und darüber ab. In Bezug auf der Wärmebehandlung,zeigt der luft-patentierte Draht den grössten Wert von HL⁄HQ und der geglühte den kleinsten.View full abstractDownload PDF (813K) -
Hisashi Yamamoto1960 Volume 24 Issue 7 Pages 421-424
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSMaking more detailed investigation of the results of our previous study on the hardening of W-Co layer electrodeposited on 0.06%C steel caused by carburizing in cracked town gas, it was found that the maximum value of 1350 Hv was obtained with heating at 1050∼1100°C for about 3 hours, and that the formation rate of tungsten carbide became more rapid at higher temperature beyond about 1000°C. An oxidizing process was observed on the surface of W-Co deposit and its carburized surface by heating in air at the range of 100∼1100°C for 1 hour; the weight increase was measured and the structure of the oxidized film was examined by X-ray and electron-diffraction methods. The results obtained were as follows: (1) Hardly any oxide film was formed on either surface by heating below 300°C. (2) The surface layers of the oxide film formed at the temperature over 400°C consisted of Co3O4 in both the W-Co deposit and the carburized surface. (3) In the inner parts of oxide films formed at above 900°C, W-Co double oxide (CoWO4) was detected in W-Co deposit, while only CoO was found on the carburized surface.View full abstractDownload PDF (637K) -
Kyuya Nagasaki, Masami Kaneko1960 Volume 24 Issue 7 Pages 425-428
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe effects of various conditions on desiliconizing of 2∼7%Si-Cu alloys by heating in nitrogen atmosphere containing 10%Si Cl4 vapour were studied. The results obtained were summarized as follows. The weight decrease by desiliconizing and the depth of desiliconized layers of the samples rose to the maximum at 500°C and 600°C respectively, and were not remarkable at about 800°C. At 500°C the weight change by desiliconizing was the greatest in 5.40%Si alloys, but at 800°C it decreased with increasing silicon content in the alloys. From these results the present authors considered that desiliconizing of Si-Cu alloys with SiCl4 proceeds along the following consecutive reactions,
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and that the former reaction to be analogous to the decarburization reaction of steel with CO2, (This article is not displayable. Please see full text pdf.)View full abstractDownload PDF (718K) -
Sadao Koshiba, Kazuo Tanaka, Akeo Sumi1960 Volume 24 Issue 7 Pages 429-432
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to improve the cutting durability of high speed steel, specimens were nitrided in commercial liquid nitrizer NS350, and examined for the hardness distribution of nitrided case, the micro-structure, the toughness and the cutting durability. As the results, the proper nitriding temperature was found to range between 500∼570°C and in this case 30∼60 min is recommended for dipping time. The depth of nitrided case obtained by the above treatment were different by specification of the specimens, standing in the range of 0.03∼0.06 mm. Case hardness was over 1200 in Vickers-Hardness number at quenched and tempered conditions. The results of tool life tests showed that nitriding of high speed steel is very effective to improve the cutting durabilities of both drills and single point tools.View full abstractDownload PDF (675K) -
Sadao Koshiba, Terumi Nishinuma1960 Volume 24 Issue 7 Pages 433-436
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe authors studied the behavior of abnormal structure of Alnico-V Type magnetic alloy and its magnetic-field-cooling treatment at low temperatures which was conducted at about 875°C. In the presence of γ phase at mono-phase temperatures, there appeared abnormal structures at room temperature due to the transformation of γ to α. Existence of abnormal structures deteriorated the magnetic properties. The abnormal structure, once produced, could not be erased at lower temperatures and persisted after magnetic-field-cooling treatment. In the case of large specimens, abnormal structures often appear resulting from the inevitable slow cooling after casting. In these cases, if the specimens are once heated to upper mono-phase temperatures and cooled in air or water, they become free of abnormal structures and the subsequent magnetic-field-cooling treatment at low temperatures becomes effective. When specimens are kept for a long time in the lower mono-phase temperature range, γ phase is apt to appear even at temperatures as low as 850° and keeping specimens too long at these temperatures should be avoided.View full abstractDownload PDF (728K) -
Sadao Koshiba, Shin Kimura, Hideki Harada1960 Volume 24 Issue 7 Pages 437-440
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to investigate the several characteristics of high-speed steels, which were made in our works, we isolated carbides in steel by electrolysis, and studied the composition, the crystal structure and the shape of carbides by chemical and X-ray analysis, electron microscopy etc. This report, especially lays stress on the relation of cutting durability and carbides in high-C high-V high-speed steel. The results obtained were as follow: (1) The contents of carbides in annealed state was about 20% and existed in three types of carbides, M6C, MC and M23C6. The content of carbide MC in this steel was several times that in other high-speed steel. (2) In quenched state, the amount of insoluble carbides was about 8%. These carbides consisted nearly of MC alone. The remainder of carbides was only M6C, (3) With the progress of tempering, the carbide contents increased, especially suddenly at 575°C. But up to 650°C, the weight percentages between the two types of carbides, MC and M6C, remained unchanged. (4) This high-C high V (XVC1) steel, in spite of low W and no Co contents, indicated an as good cutting durability as W-Co (X00) steel. We consider, this is due to the presence of a number of small and hard carbides MC grains effectively serving for the purpose.View full abstractDownload PDF (622K) -
Kazuo Tsuya1960 Volume 24 Issue 7 Pages 440-444
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to study the mechanical properties of slack-quenched steel, the influence of bainite on the ductility of steels has been investigated. The principal results are as follows: (1) The detrimental effect of bainitic structures formed by continuous cooling transformation increases as the amount of bainite is increased. (2) The bainitic structures isothermally formed at higher temperatures remarkabley damage the ductility, though the detrimental effect of bainite formed at temperatures near Ms is negligible.View full abstractDownload PDF (566K) -
Gorô Yokoyama1960 Volume 24 Issue 7 Pages 445-449
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIt was proved that the corrosion potential of metals in a very small area can be measured by means of a microelectrode. The microelectrode is a thin-walled glass capillary containing a corrosive solution. The tip of electrode is so fine that the area contact with metal surface is limited to 0.02 to 0.03 mmφ. 10%NaCl and 20%H2SO4 solution were preferred as the corrosive media. The corrosion potentials at Zn, Fe, Cd, Sn, Cu, Al and Sb were measured by the microelectrode and they were compared with the result by the normal method. When 20%H2SO4 solution was introduced into the capillary, the potential values obtained by the two methods agreed very well with each other. However, in the case of 10%NaCl in 0.02∼0.03 mmφ capillary, some discrepancies were noted.View full abstractDownload PDF (894K) -
Gorô Yokoyama1960 Volume 24 Issue 7 Pages 449-452
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe metallurgical structure of Cd-Sb alloy is devided into three phases. They are α, β and γ solid solution. Since the corrosion potential of alloy consisting of two or more phases is represented in the one of the least noble phase, the potential of the interphase or the nobler phases cannot be observed by the normal method. The microelectrode system described in the previous report was applied in this case, and also the potentials of the nobler phases could be separately measured. A diffused layer of Cu into Zn was subjected to microelectrode inspection and it was discoverd that the layer was separated into three parts showing different potentials.View full abstractDownload PDF (961K) -
Tadao Sano, Masanobu Miyake, Takao Konishi1960 Volume 24 Issue 7 Pages 452-456
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSA study has been made of the solution-rate of dissolution of solid nickel in liquid bismuth under static and isothermal condition, at the temperature in the range 300∼400°. A continuous measurement of the solution-rate has been carried out by the electric resistivity method which is based on the measurement of resistivity of bismuth-solution varying with change in nickel-concentration. By this method, the solution-rate was obtained within the accuracy of 0.08 at%. On the other hand,the ordinary method by chemical analysis was done on the same system, showing the results in good agreement with those by the electric resistivity method. The solution-rate obtained has been found to obey an equation of the form n=ns{1−exp(−kSt⁄V)} and the activation energy of the dissolution was estimated to be about 2.2 kcal/mol.View full abstractDownload PDF (686K) -
Tadashi Ichiyama, Masayuki Kawasaki, Kikuo Takashina1960 Volume 24 Issue 7 Pages 456-460
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe internal friction in quench-hardened plain carbon steels containing 0.68%, 0.85% and 1.14% carbon respectively was measured as a function of temperature, using a torsion pendulum at about 2 cps. The relaxation peak due to the stress-induced ordering of carbon atoms was observed in an as-quenched specimen of 0.68% carbon steel. The presence of such a carbon-peak seems to be the result of an unavoidable ferrite precipitation during quenching. On the other hand, such a carbon-peak was not detected in the as-quenched steels containing 0.85% and 1.14% of carbon respectively. The absence of a carbon-peak in as-quenched steels supports the assumption that the martensite in carbon steels has a superlattice. The Köster effect was observed in as-quenched martensite as well as cold-worked iron. In tempered martensite, a distinct relaxation peak was observed at about 225°C and this peak was found unstable. The activation energy of the process causing this peak is 32,600 cal/mol and this peak is characterized by a distribution of relaxation times. This peak is considered to be due to the interaction between carbon atoms and dislocations. A continuous increase in internal friction with an increase of measuring temperature from about 280°C was observed in tempered martensite. This high temperature relaxation seems to be caused by the coupled relaxations of an irregular network of sub-grain interfaces.View full abstractDownload PDF (774K) -
Tomisaburô Nara, Yoshito Yamada1960 Volume 24 Issue 7 Pages 460-464
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn order to obtain an extra pure copper the zone refining process has been applied to vacuum-melted copper. Some technical problems on zone refining were also discussed on the basis of the results of preliminary experiments. The following results were obtained on the ingot zone refined by sixteen passes of the molten zone. (1) Ag, Si, Mn, As, Pb and Sn in the original copper were concentrated markedly to the direction of travel of the molten zone but Al and Fe were not concentrated while Ca and Mg were distributed irregularly. (2) It was assertained by a qualitative spectrographic analysis that the purity of the most refined part was much higher than that of the Johnson Matthey’s spectrographically standardized copper (99.999%). (3) The electrical resistivity of the purest part was 1.667±0.002 μΩ cm (at 20°C) after annealing. (4) In the case of highly cold-drawn wires of zone-refined copper, a decrease of electrical resistivity was observed by annealing even at room temperature for long time, which seems to be dependent upon the high purity of the wires.View full abstractDownload PDF (728K) -
Hakaru Masumoto, Hideo Saitô, Minoru Takahashi1960 Volume 24 Issue 7 Pages 465-469
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSThe magnetization and magnetostriction at high temperatures in a Fe3Cr alloy thermally demagnetized were measured simultaneously and their time changes at constant temperatures under external fields of 71.3 Oe and 285 Oe have been continuously traced from the instant of the application of a field. Then, the magnetization and magnetostriction at room temperature were measured after the isothermal magnetic annealing, which was continued till the time changes were completed. The amount of the time change of magnetization and magnetostriction at high temperatures becomes larger as the duration of the application of the field is prolonged and the strength of applied field is raised. The effect of isothermal magnetic annealing begins to appear at about 400° and increases with a rise of temperature, till the effect reaches its maximum at about 530°. Then, it decreases rapidly and becomes very small in the temperature range higher than the transformation temperature of Fe3Cr superlattice. With progress of the annealing, the positive magnetostriction becomes smaller and even changes to a negative one in the case of the magnetic annealing for 150 hours under the external field of 285 Oe in the temperature range from 500° to 540°, showing that there is an anisotropy of magnetostriction in Fe3Cr alloy. The effect of the isothermal magnetic annealing on the magnetization and magnetostriction at room temperature in Fe3Cr alloy are almost similar to that at high temperatures, excepting that the maximum permeability is larger when the alloy was annealed under the external field of 71.3 Oe, than in the case of the annealing under the field of 285 Oe. According to these results, it can be concluded that the relaxation of the magnetization and magnetostriction is caused by a micro-creep or a phenomenon similar to it, due to magnetostriction at high temperatures, and that the superlattice transformation plays an important part in the progress of the effect.View full abstractDownload PDF (718K) -
Tomo-o Satô, Taiji Nishizawa, Koreaki Tamaki1960 Volume 24 Issue 7 Pages 469-473
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSCarbides existing at equilibrium with austenite in molybdenum steels were studied by electrolytic isolation and by subsequent chemical and X-ray analyses. Three kinds of carbides, M3C, ξ and M6C, were found in the steels quenched from 900°C. Besides these carbides, M2C appeared in the case of short time austenitizing. By addition of Cr (about 1%) to molybdenum steels, M23C6 was stabilized, and this carbide was also found in the quenched structures. On the bases of these experimental results, the stable and the metastable carbide phase diagrams at 900°C were determined. It was confirmed that MaCb found by Kuo (1953) in several tempered molybdenum steels was identical with ξ carbide, which had been first noticed by Takei (1932). The X-ray photograph of ξ carbide resembles to that of Hägg’s iron percarbide, and so the crystal structure of ξ carbide is probably the orthorhombic.View full abstractDownload PDF (665K) -
Tomo-o Satô, Taiji Nishizawa1960 Volume 24 Issue 7 Pages 473-477
Published: 1960
Released on J-STAGE: April 04, 2008
JOURNAL FREE ACCESSIn the present research, X-ray and chemical analyses were carried out on carbides isolated electrolytically from several chromium, molybdenum, tungsten and vanadium steels tempered at 400∼730°C. Moreover, the volume change of these steels on tempering was examined by means of a differential dilatometer, and the correlation of the carbide reactions and the volume change occurring in the fourth stage of tempering was studied. It was found that the formation of VC, Mo2C, W2C and M6C at the expense of cementite causes a distinct expansion of the steel, but the conversion of cementite into M7C3 and M23C6 is not accompanied by a volume change of the steel. The cause is considered to lie in the difference in crystal structure of each carbide. That is, the structures of VC, Mo2C,W2C and M6C are so-called interstitial ones, in which the carbon atoms fit into the octahedral holes, and the interatomic distances between metal to metal atoms are larger than those in the carbides having complex structures as cementite, M7C3 and M23C6. This reasoning is possibly available to explain why the secondary hardening phenomenon occurs in vanadium, molybdenum and tungsten steels, but not in chromium steels, during the fourth stage of tempering.View full abstractDownload PDF (791K)
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