Journal of the Japan Institute of Metals and Materials
Online ISSN : 1880-6880
Print ISSN : 0021-4876
ISSN-L : 0021-4876
Volume 17 , Issue 9
Showing 1-15 articles out of 15 articles from the selected issue
  • Yasumitsu Shimomura
    1953 Volume 17 Issue 9 Pages 421-424
    Published: 1953
    Released: April 04, 2008
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    In the present experiment it is clarified that the lattice deformation of nickel oxide can be controlled by dissolving the foreign cations. That is to say, if it contains aluminium irons, its deformation increases (Table 3); on the other hand when copper is dissolved in it, the lattice constants vary as equations (1), (2) and (3) (Fig. 1). Thus the oxide containing 24 at.% Cu (referred only to cations) has a cubic structure at the ordinary temperature, but its antiferromagnetic Curie point is higher than 130°C (Fig. 2). These facts show that the deformation must be affected not only by the exchange interactions, but also by the ionic radius ratio. According to such a view, it can be well understood why the structure of nickel oxide film is cubic at room temperature.(2) The followings are also shown: When the solute copper becomes as rich as 28 at.%, it has a tendency to enter chiefly into one of the {100} planes (Table 1), but at a lower concentration, no such tendency is observed; and at the concentration where the deformation disappears, one fourth of the magnetic ions with an antiparallel spin in each of the first and second nearest neighbors is replaced by copper ions.
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  • Mikio Yamamoto, Jirô Watanabe
    1953 Volume 17 Issue 9 Pages 424-427
    Published: 1953
    Released: April 04, 2008
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    Light-figure phenomena have been studied on single crystals of silver etched under various conditions, especially with the object of finding out light figures suitable for determining orientation by the light-figure method. Experimental results obtained are summarized in Table 1 of the text. It was found that clear {100}, {110} and {111} light figures, suitable for determining orientation were produced by silver crystals etched for a short time with such strongly oxidizing etchants as concentrated sulphuric acid (at 50∼60°C) and 50 percent sulphuric acid saturated with potassium bichromate.
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  • Takuro Saga, Ohmi Miyakawa
    1953 Volume 17 Issue 9 Pages 427-431
    Published: 1953
    Released: April 04, 2008
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    It is well known that the hardness numbers of metallic materials change considerably under different conditions. In spite of the fact that a quantitative study is very important for the stochastical analysis of the measured hardness values, very few studies on the subject have been reported. Experiments on Vickers hardness in various materials, including pure iron, carbon steel and brass, were carried out under loads of 1 to 100 kg. The results obtained were as follows:—(1) The populations (Vickers hardness values) show normal distributions. (2) The standard deviation σ (coefficient of variation C) of the populations varies with the applied load P in the following relation; σ·P1⁄4=constant, or C·P1⁄4=constant. (3) Under a definite load, the values of σ or C for homogenous materials, such as pure iron, eutectoid steel and 7∼3 brass, vary little according as the grain size of the materials, but in heterogenous materials, such as carbon steel, they vary considerably, as shown in Fig. 2. (4) The values of C are generally expressed as follows: C=(2.5∼4)P, where P−1⁄4 is in kg.
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  • Kichizo Niwa, Yoshinobu Katsufuji, Tatsuo Maekawa
    1953 Volume 17 Issue 9 Pages 431-434
    Published: 1953
    Released: April 04, 2008
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    For studying the reduction mechanism of iron pyrite with hydrogen this process was investigated kinetically within the range of 460-550°C, by measuring continuously the weight loss of the samples with a quartz spring balance and by analysing the change of phases in the course of reduction with X-ray diffraction method. Although the rate of reduction is approximately proportional to the fraction of pyrite remaining to be reduced at the initial step of reaction, the relationship characteristic of a first order reaction deviates with time and the rate constant increases gradually. This tendency becomes remarkable at about 60% decomposition. Identification of the phases was accomplished by taking X-ray photograms of powdered samples in the course of reduction, using characteristic FeKα radiation in a Debye camera. X-ray diffraction patterns of the samples indicate the following results: In the course of reduction of FeS2, at first, FeS1.15 phase is separated to give a diphasic system. As long as FeS2 exists, no FeS phase is detected. After FeS2 phase has disappeared by reduction, the decomposition of FeS1.15 phase to FeS takes place. Consequently, the reduction mechanism of FeS2 can be represented as follows:
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    \ oindentwhere FeS1+x corresponds to FeS1.15. From the fact that no FeS phase appears in the presence of FeS2 phase, it is concluded that the reaction (2) proceeds fairly rapidly in comparison with the other reactions. The increace in the rate of reduction can be attributed to the reaction caused by FeS1.15 phase according to the equation (2) and (3).
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  • Tunezô Saitô, Yasuji Kawai
    1953 Volume 17 Issue 9 Pages 434-438
    Published: 1953
    Released: April 04, 2008
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    As the first step in the study on the kinetics of desulphurization of iron by slag, the rate of diffusion of sulphur in molten CaO-SiO2-Al2O3 slag was determined by the use of radioactive sulphur S35. Iron sulphide powder made from barium sulphide containing S35 was mixed with slag powder and after melting, it was poured into a graphite tube to form a radioactive sample. Then, it was coupled with a graphite crucible containing a non-radioactive sample the composition of which was nearly the same as the former. This couple was heated in a high frequency induction furnace in nitrogen atmosphere for a definite time. After cooling i in the furnace, small pieces were cut off successively from the top to the bottom and the radioactive intensities of polished surfaces of the remainder were measured by a Geiger-Müller counter. From these measurements, the diffusion coefficient of sulphur in molten basic slag was determined as follows: D=1.4e−49000⁄RT. The value of diffusion coefficient in acid slag at 1440° was nearly the same as in basic slag, but values at higher temperatures could not be determined owing to the gas evolution by the reaction, SiO2+2C→Si+2CO. As shown from the results, the rate of diffusion of sulphur in molten slag is so slow that it seems to be the rate controlling factor governing the desulphurization of iron by slag.
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  • Sôsuke Uchida
    1953 Volume 17 Issue 9 Pages 438-441
    Published: 1953
    Released: April 04, 2008
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    The effect on the reaction of steel in carburizing atmosphere produced by combustion of charcoal in wet air and mingled with ammonia gas was studied under various conditions, especially, on the subject of the carbonitriding of the steel by the gas, and the following results were obtained: (1) The same degree of carbonitriding was obtained with lower gas velocity than in mere carburizing. (2) The relation of carbonitriding (in mg/cm2, weight %) and treating time was illustrated in parabolic curves. (3) The carbonitrided quantity increased with the increase of NH3 gas at lower temperatures, but decreased at higher temperatures. (4) Sooting decreased even at low temperature by addition of NH3 gas to the carburizing atmosphere.
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  • Goro Shimaoka, Kichizo Niwa
    1953 Volume 17 Issue 9 Pages 441-445
    Published: 1953
    Released: April 04, 2008
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    The procedures of electrolytic polishing of 18-8 and 18 Cr stainless steel in electrolyte containing H2SO4, H3PO4 and glycerine (1:3:1, by vol.) were examined by electron diffraction. (1) In the first process of electrolysis, the surfaces gave sharp α-Fe patterns. In the process of brightening, the surfaces gave diffuse patterns of α-Fe overlapped by Fe3O4. These diffuse patterns changed into 2 diffuse haloes when the surfaces were treated in this process again and again. In the process of active gas evolution weak γ-FeOOH patterns appeared. (2) Though slightly electrolytically polished surfaces had a tendency to increase oxide formation, sufficiently polished surfaces showed rather decrease or stop of oxide formation. (3) Transmission patterns of thin sections in electrolytically polished surfaces showed no reformation of elements in alloys. (4) Results of low temp. air oxidation indicated that the oxide films of electrolytically polished surfaces might be solid soln. of γ-(Fe,Cr)2O3, in which Cr content might be richer than Fe. (5) It was concluded that, in the process of brightening, dissolution and formation of surface oxide proceeded almost continuously under the condition in which amorph. oxide layer covered the surface, and this resulted in a bright surface.
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  • Kiichiro Shinji
    1953 Volume 17 Issue 9 Pages 446-449
    Published: 1953
    Released: April 04, 2008
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    The auther carried out the investigation of Cr stainless steel and its modifications used for turbine blades and parts of chemical instruments which require corrosion resisting property. The results obtained on 13 Cr stainless steel are as follows: (1) Potassium ferricyanisde method for inspecting non-metallic inclusions which tend to be contained in this kind of steel is effective to detect them rapidly and easily all over the surface. (2) Non-metallic inclusions detected by potassium ferricyanide method have no effect on mechanical durability. (3) Tensile strength is increased by adding Cu or Mo, but elongation and reduction are decreased. (4) Effects of Cu and Mo on corrosion resisting properties against inorganic and organic acids and salt solutions were investigated at room temperature and their boiling points. Corrosion resisting property against HCl at room temperature is decreased by adding Cu but this result is different from those of published experiments.
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  • Yachiyo Katita
    1953 Volume 17 Issue 9 Pages 450-452
    Published: 1953
    Released: April 04, 2008
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    In the photometric determination of arsenic with molybdenum blue, phosphorus shows the same absorption as arsenic. Therefore, the determination of pure arsenic was studied after the separation of phosphorus from arsenic. Before the reduction to molybdenum blue, phosphorus in the form of molybdate compound was extracted with organic solvents, but not arsenic. This treatment was applid to the photometric determination of arsenic, and satisfactory results were obtained.
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  • Yasumasa Sakuma, Takashi Ishida
    1953 Volume 17 Issue 9 Pages 453-456
    Published: 1953
    Released: April 04, 2008
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    The wear of sewing machine needles is increased by the drop of hardness of the needle tips. Generally, the hardness of the tips is considerably decreased by tempering. The results of the present study for preventing such a drop of hardness during tempering are shown in Figs. 4 and 5. The hardness is kept at Hv 750 grade by a tempering method in which approximately 7 mm of the needle tips are kept from dipping in the tempering oil.
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  • Tokutaro Hirone, Kazuo Kamigaki
    1953 Volume 17 Issue 9 Pages 456-459
    Published: 1953
    Released: April 04, 2008
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    Attenuation of longitudinal ultrasonic waves in polycrystalline pure aluminium rods (99.9%) was measured with impulse method at several frequencies between 2 and 25 megacycles per second with various heat treatments of rods. Due to the successive heat treatment the mean grain diameter of the aluminium rods made a growth from about 0.2 to 3 mm, as shown in photo 1. Measured values of attenuation are plotted in Fig. 3 as a function of frequency. As it shows, the value of attenuation changes greatly with the grain sizes of the specimens. When grain size is small, attenuation is nearly propotional to frequency and the proportional constant increases with grain diameter. For large grain size, however the attenuation curves seem to saturate at high frequency range. If the grain diameter becomes very large, attenuation reaches a constant value independent of frequency. Attenuation constant of the present experiment is considerably smaller than the previous results by Mason and McSkimin and Roth. Those changes of attenuation can be explained as follows. First, the attenuation of ultrasound in proportional range is due to elastic hysteresis loss. If the wave length becomes shorter, a considerable part of the attenuation is caused by the Rayleigh scattering and is proportional to the fourth power of frequency. If wave length becomes nearly equal to grain size, attenuation is proportional to the second power of frequency due to the change in phase of traveling sound at the grain boundaries. Last stage of constant attenuation will be explained as a result of reflection and refraction of the sound at the grain boundaries.
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  • Kazuo Hori
    1953 Volume 17 Issue 9 Pages 460-462
    Published: 1953
    Released: April 04, 2008
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    In former reports, it was stated that the addition of titanium to Al-alloys decreased their solidifying shrinkages and its effects were examined quanitatively, these effects of titanium were very remarkable but in utilization of titanium for Al-alloys, these effects on solidifying shrinkages were not yet positively utilized. In this report, the effects of titanium on castability were studied in co-existence of other prominent elements, such as Si and Cu, using the author’s instrument. The results obtained were as follows: 1. Al-Ti system. The results of this system resemble to the one reported previously in solidifying shrinkage and at 0.4%Ti, the runnability was improved greatly. 2. Al-Si-Ti system. In this system, the addition of titanium was fixed at 0.4% and Si content was changed. An addition of 0.5% Si showed the smallest runnability but the runnability was improved with increasing Si. 3. Al-Cu-Ti system. An addition of 0.5% Cu gave the best runnability in this system but addition of more Cu was not effective in improving the castability even in co-existence with titanium.
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  • Takashi Ikeno
    1953 Volume 17 Issue 9 Pages 462-466
    Published: 1953
    Released: April 04, 2008
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    The relation between casting techniques and cracks appearing in aluminium ingots has been studied with a practical tilting mould. The results obtained may be summarized as follows: The pouring temperature and the temperature of moulds affect seriously the cracks of aluminium ingots. The rate of casting, the shape of the runner, the degree of tilting the mould, etc. also influence the cracking. Among these, it was found: When the pouring temperature is high the temperature gradient along the vertical direction becomes large, and the gradient in the neighbourhood of the gate becomes much larger than that in the opposite portion, and in such a condition, cracking appears mainly on the gate side.
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  • K. Iwase, K. Ogawa, T. Takada
    1953 Volume 17 Issue 9 Pages 467
    Published: 1953
    Released: April 04, 2008
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  • K. Iwase, K. Ogawa, T. Takada
    1953 Volume 17 Issue 9 Pages 468
    Published: 1953
    Released: April 04, 2008
    JOURNALS FREE ACCESS
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