Journal of the Japan Institute of Metals and Materials
Online ISSN : 1880-6880
Print ISSN : 0021-4876
ISSN-L : 0021-4876
Volume 16 , Issue 9
Showing 1-15 articles out of 15 articles from the selected issue
  • Yûki Shirakawa, Tôru Ôhara, Takeshi Abe
    1952 Volume 16 Issue 9 Pages 473-475
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The Wiedemann effect of “Alfer” (12.91% Al-Fe alloy) was measured with the annealed specimen at high temperatures. As the temperature rise, the effect gradually decreases at the eonstant current through the specimen, and also the higher the temperature is the weaker the field is for the maximum effect. Keeping the eurrent through the specimen as well as the longitudinal field constant, the effect gradually decreases with the rise of temperature, and becomes extremely small at the magnetic transformation temperature of the Fe3Al superlattice, and vanishes at the magnetic transformation temperature of α phase. The effect of Ni and Fe was measured to compare with that of Alfer. The temperature change of Ni is similar to that of Alfer, but the change of Fe is different from the both and gradually increases as the temperature rise, and after reaching a maximum at about 600°, rapidly decreases, becoming zero at the magnetic transformation temperature.
    Download PDF (456K)
  • Mikio Yamamoto, Ryôfu Miyasaya, Jirô Watanabe
    1952 Volume 16 Issue 9 Pages 475-478
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Light figures produced by the three principal crystallographic planes {100}, {110} and {111} of etched single crystals of iron-aluminium alloys containing less than 6% Al were observed and their suitability for the orientation determination byteh light-figure method was examined. It was found that light figures revealed by etching for several minutes with 20% aqueous solution of ammonium persulphate were suitable to the orientation determination of iron-aluminium single crystals containing less than 4% Al,and those produced by etching for several minutes with saturated aqueous solution of ferric chloride were appropriate for cases of single crystals of pure iron and alloys containing more than 4% Al.
    Download PDF (776K)
  • Ryûtaro Nagai
    1952 Volume 16 Issue 9 Pages 479-482
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Download PDF (478K)
  • Tetsuo Yagihashi, Tadashi Satô
    1952 Volume 16 Issue 9 Pages 482-486
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The authors measured the equilibrium of the reaction, Cu2S(S)+H2(g)\ ightleftarrows2Cu(S)+H2S(g) at the temperature range from 700° to 900° by means of flow method. The equations for the temperature function of the equilibrium constant and Gibbs’ free energy changy in the above reaction from the experimental results were obtained as follows: logK_P=log\fracp_H_2SpH_2=\frac-1214T-1.393
    ΔF=5555+6.377T Then, comparing the thermodynamical data of FeS with those of Cu2S, the authors concluded that the former was unstable at higher temperature range, 930∼1000°C and the lattr at lower temperature range, 700∼930. Furthermore, combining the above equation with the equation of the temperature function of dissociation constant of hydrogen sulphide gas the following equation were obtained: & 4Cu+S_2 \ ightleftarrows2Cu_2S
    & logK’=log\frac1p_S_2=\frac14578T-4.896
    & ΔF°=-66694+22.399T
    Download PDF (666K)
  • Masao Homma, Yasuhiko Hashimoto
    1952 Volume 16 Issue 9 Pages 486-492
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The change of structure caused by a minute diffrence of oxygen content in Fe-C, Fe-Si-C and commercial grey cast iron was studied for a purpose regulating the oxygen content of each melt by covering it with specially prepared flux. The flux used acted as the oxidizing or reducing agent toward the melt. The alloy having a coarse flake graphite structure was used as a starting substance and its melt was subjected to the action of the flux. The relation between oxygen content and the structure of the alloy thus treated is shown in Table
    From Table 2 it is to be noticed that similar cast iron structures are reguraly obtainable by reducing or increasing the oxyen content of the flake graphite-cast iron melt. The mechanism of formation of such structures is under discussion.
    Download PDF (1900K)
  • Yuzo Nakamura, Motoi Nishizaka
    1952 Volume 16 Issue 9 Pages 492-495
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    No systematic investigation of recrystallization diagram to have been carried out on the high purity aluminium. The authors seems investigated the recrystallization diagrams of the high purity aluminiums with a purities of 99.998, 99.992 and 99.92%, comparing with the commerical aluminium (99.5%) to determine the coarsining range. In the case of the initial sheet annealed at 550° which is usually adopted it was found that the coarsening phenomenon took place in the lower rolling reduction less than 5%, as expected in all pure aluminiums. On the other hand, in the case of the initial sheet annealed at 350° from the standpoint of practice, it was found that a remarkable coarsening took place only in 99.92% Al and its range seems to be limitted within the purities from 99.991 to 99.985%, And its coarsening did not take place in lower reduction less than 5% as expected, but it did in higher reduction such as 10∼45%. Another coarsening phenomenon was observed in 99.5% Al which had undergone a heavier reduction, of 45∼65%.
    Download PDF (1438K)
  • Namio Kawashima, Yuzo Nakamura
    1952 Volume 16 Issue 9 Pages 495-499
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Download PDF (643K)
  • H. Hagiwara
    1952 Volume 16 Issue 9 Pages 500-503
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The reduction equilibrium of sulphur in molten lead by hydrogen was investigated in the temperature range of 800∼950°C. It is concluded that sulphur in molten lead may be regarded as an ideal solution within the limit of experiment. Experimental results are summarized as follows: & S(% in Pb)+H_2 \ ightleftarrowsH_2S;
    & K=P_H_2S/P_H_2[S% in Pb]=K_p/[S% in Pb],
    & logK=-2,243/T+0.342,
    & ΔF°=10,285-1.565T
    By combining the dissociation equilibrium of hydrogen sulphide with the above results, the following results were obtained: & 2S(% in Pb) \ ightleftarrowsS_2; K’=P_S_2/[S% in Pb]^2,
    & logK’=-13,949/T+5,838,
    & ΔF°=63,817-26.709T.
    Download PDF (592K)
  • Yoshikazu Hosoi
    1952 Volume 16 Issue 9 Pages 503-508
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    In the previous works, we reported in detail the various characters of β′ and β″ which were determined by H. Imai and M. Hagiya. As the microstructures of the quenched specimens are varied owing to the quenching temperatures and concentration of Sn, many other tempering phenomena do not coincide with each other. We reexamined the tempering mechanism of β tin bronze by means of the dilatometrid and specific heat measurements.
    As the microstructures of the quenched specimens are classified into the following three kinds, the results obtained are summarized as follows:
    (This article is not displayable. Please see full text pdf.)
    That is, β: residual β, βQ′: quenched aciqular structure, βA′: tempered state at about 250° of βQ′ or β, is aciqular, β′: tempered state at about 250° of β, is not aciqular, β″: re-arranged state of βA′ or β′.
    Although the first gradation of βA′ or β′ is the tempered state at about 250°, the change to next one is continuously occurring except in the case of (c). The second gradation of β″ which is the lowest electric resistance and max. hardness is the tempered state at about 300°. At the third process of β″→(α+δ), it was thought that β″ was thrown into confusion in atomic arrangement at about 300∼330° before the decomposition to (α+δ) which was accomplished at about 420°.
    Download PDF (940K)
  • Ikushiro Shinya
    1952 Volume 16 Issue 9 Pages 508-510
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The author describes an improved method for the simultaneous and rapid estimation of oxygen and sulphur in tough-pitch copper. The main past of appartus is similar to that used in the determination of oxygen in iron and steel, which had been established by the Nippon Gakuzyutsu Shinko Kai. Only the H2S absorbing tower is attached to the improved method. According to current methods, the two elements are deter mined individually, and the determination of sulphur takes so long a time as 6 days. On the contrary, the improved method can determine oxygen and sulphur at the same time in 2 hours. The errors by the improved method are not greater than the usual method.
    Download PDF (437K)
  • Sadao Koshiba
    1952 Volume 16 Issue 9 Pages 511-513
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The author carried out a series of experiment on the effect of each elements, i.e. C 1.0∼1.4%, Cr 3∼6%, W 4∼1%, V1∼3%, for standard composition containcing C 1.1%, Cr 4%, W 6%, Mo 2%, V2% and studied changes in their hardness and microstructures brought about by different heat treatments, and also tested their cutting durability by putting them in actual service. As the results of this investigation, it is ascertained that moderate composition are C 1.0∼1.2%, Cr 4.0∼5.5%, W 5∼7%, Mo 2%, V 1.8∼2.8%, and that this high speed steel containing moderate composition have better cutting durability than low tungsten high speed steel containing W 11%.
    Download PDF (465K)
  • Minoru Yohda
    1952 Volume 16 Issue 9 Pages 514-517
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    In the production of regenerated pig iron, small blast furnaces areused sometimes, but to obtain iron suitable for casting as well as iron castings directly, regenerating cupolas (cupola type furnce) are generally used: in the present study, the latter kind of the furnace is used. The experimental result shows us that (1) the pressure of the blast in the present case is similar to that in the ordinary cupola because the furnaces are of similar heights, while (2) the amount of the blast rather resembles to that in the blast furnace because the reactions taking place in the furnaces the reduction of oxides, the absorption of carbon and silicon in iron, etc.… are alike.
    Download PDF (607K)
  • Susumu Oki, Ren Obata
    1952 Volume 16 Issue 9 Pages 517-521
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    It is already well known that the grain boundaries of the primary austenite of low carbon steel usually do not coincide with those of the primary dendrites, and also that they have little effect on the mechanical properties after the heat treatment for grain-refining. But the authors have often experienced to observe a remarkable embrittlement occurring at some parts of castings such as spokes and test coupons attached to the bosses of driving wheels of locomotives, in spite of normal heat-treat- ment for grain-refining. The distinctive features of the appearances of this brittleness are as follows: (1) Coarse granular fractures are distinctly observed along the interfaces of grains of primary austenite. (2) In the microscopic specimens, etched with aqueous solutions of 10% HNO3-10% H2SO4 and repolished, network of pit-chains are clearly obeserved. (3) Loss in elongation is not so remarkable. The coarse fractures and pit-chains are gradually eliminated on eating the specimens, partly at about 1300° and entirely at about 1450°.
    The authors tried to reproduce the embrittlement artificially by means of monotonous cooling of the specimens from very high temperatures at various cooling rates, but in vain. Later they, however almost succeeded in to do so by keeping the specimens at 1000° for one or two hours after fairly rapid cooling from solidifying temperature. From the results of these experiments, an idea was introduced for the reason why the embrittlement occurred only at the peculiar parts of castings. These parts of castings are rather thin in themselves but they are attached to some large masses, and so they cool rapidly just after the solidification and then very slowly between about 1000° and 800°. So the authors reached the conclusions that the embrittlement would be caused by precipitation of certain elements or compounds along the grain boundaries of primary austenite. This phenomenon may be substantially the same with so called “Overheating”. The physical and chemical properties of the precipitates are not yet investigated.
    Download PDF (980K)
  • Tsunenobu Shigematsu, Hirozo Kimura
    1952 Volume 16 Issue 9 Pages 521-525
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Gravimetric and colorimetric methods for the determination of a wide range of sodium in metallic calcium by means of uranyl-nickel-acetate reagent was studied. A gravimetric procedure was utilized for the determination of industrial crude calcium containing up to 1 or 2 percent of sodium, and a colorimetric procedure was utilized for the determination of microquantities of sodium in distilled calcium.
    Download PDF (626K)
  • Tsunenobu Shigematsu, Hirozo Kimura
    1952 Volume 16 Issue 9 Pages 525-527
    Published: 1952
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    A sensitive colorimetric method for sodium by means of uranyl-nickel-acetate reagent have been applied to the analysis of sodium in aluminium, magnesium and their alloys.
    Aluminium and its alloy were dissolved, and after aluminium was removed as AlCl3·6H2O by saturating with hydrochloric acid gas or adding concentrated hydrochloric acid, sodium in the solution was determined colorimetrically. Under suitable condtions, less than 200 milligrams of magnesium did not interfer with the determination of microgram quantities of sodium; thus sodium in magnesium was directly found.
    Download PDF (497K)
feedback
Top