Tetsu-to-Hagane
Online ISSN : 1883-2954
Print ISSN : 0021-1575
ISSN-L : 0021-1575
Volume 48, Issue 8
Displaying 1-14 of 14 articles from this issue
  • [in Japanese]
    1962 Volume 48 Issue 8 Pages 923-924
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • Shiro BAN-YA, Sachio MATOBA
    1962 Volume 48 Issue 8 Pages 925-932
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    The equilibrium of CO-CO2 gas mixture with carbon and oxygen dissolved in liquid iron was studied in the range from a dilute solution to a concentration with 2·5% carbon at 1460, 1560, 1660 and 1760°C
    The results obtained gave the following equatians:
    C+CO2=2CO…… (1)
    logK1 (=Pcoco2/Pcoco2·aC) =-7, 558/T+6·765
    ΔF°1=34, 580-30·95T
    O+CO=CO2…… (2)
    logK2 (=Pcoco2/Pcoao) =8, 718/T-4·762
    ΔF°2=-39, 880+21·78T
    C+O=CO…… (3)
    logK3 (=Pco/ac·ao) =1, 160/T+2·00
    ΔF°3=-5, 310-9·16T
    The relationship between the activity coefficient of carbon or oxygen, and the concentration of carbon was expressed by the following equations, where the mole fration of carbon was below 0·09Nc:
    logγ (c) c=6·40Nc……<0·09Nc
    logf (c) o=-9·05Nc……<0·09Nc
    From these results activity coefficient of carbon in liquid iron was evaluated over the whole range of carbon of the Fe-C alloy.
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  • Study on continuous casting of steel-VIII
    Yoshio AKETA, Kiyoto USHIJIMA
    1962 Volume 48 Issue 8 Pages 933-940
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Homogeneity of chemical compositions and constitution of continuously cast billets are examined. Si-Mn spring steel is cast into billets with different sectional sizes, 91mm_??_, 130 mm _??_ and 170mm _??_, and each casting time of a heat is 60mn. Results of analysis, observation and testing of billets are as follows.
    1. The distribution of chemical compositions, oxygen content, sand content and content of nonmetallic inclusions are fairly homogeneous not only transversally but also longitudinally in spite of a long casting time.
    2. Constitution of a billet of as-cast state consists of a chill zone, a coarse dendritic zone and a free crystal zone.
    3. When a billet is rolled, its constitution of three zones, as mentioned above, is made homogeneous and the reduction ratio of area more than 10 gives it homogeneous mechanical properties.
    It is clear that a continuously cast billet has good characteristics as the rolling material.
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  • Yuzo HOSOI
    1962 Volume 48 Issue 8 Pages 940-946
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    The secondary hardening behavior of “ausformed” 13 Cr stainless steels was investigated. Steels were deformed by rolling at 450°C or 650°C in the metastable austenite condition prior to martensite transformation and subsequently tempered up to 550°C. Secondary hardening did not appear clearly in the ausformed and tempered specimens when the amount of deformation was increased, while it occurred in the conventionally quenched and tempered specimens at 450°C. By measuring the change in a half-value breadth of X-ray diffraction line with tempering and extracting carbide electrolytically from heat-treated steels, it was assured that this phenomenon could be explained by one of the following two reasons. (1) Precipitation process of carbide was accelerated by plastic deformation of austenite matrix before quenching and precipitation temperature was lowered to a low temperature, then it followed that softening of martensite by tempering would be cancelled by this accelerated precipitation hardening. Or, (2) hardening due to lattice strain produced by plastic deformation was so high that hardening due to precipitation would be covered with it.
    Effects of austenitized temperature and deformation temperature on hardening were also studied and discussed.
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  • Study on the graphitization of high-carbon steels-II
    Naomichi YAMANAKA, Kunio KUSAKA
    1962 Volume 48 Issue 8 Pages 946-953
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Several experiments have been made in an effort to reveal some of the fundamental factors which play a role in the graphitization of pure high-carbon steels deoxidized with aluminum and silicon. The authors suggested following mechanism for graphitization of high carbon steel.
    (1) It is considered that the graphitization proceeds by the ‘nucleation and growth’ reaction. In order for cementite to decompose into graphite and ferrite, nuclei must be formed. The growth of graphite nodules takes place by the diffusion of carbon atoms through the ferrite lattice.
    (2) It is considered that these nuclei may be formed by decomposition of unstable cementite, and the rate of nucleation depends on the form and composition of cementite. Nitrogen-and carbide-forming elements such as chromium, manganese, tungsten and molybdenum make cementite stable. Aluminum, silicon, titanium, zirconium and boron tend to make cementite unstable and promote graphitization through its role as a scavenger for nitrogen. A small amounts of tin and arsenic make a steel highly resistant to graphitization.
    (3) Graphite forms more rapidly in steels after quenching to martensite of cold working than after normalizing or annealing. It is considered that the strain added to cementite particles by prequenching to martensite and tempering or cold working would tend to decrease the stability of cementite.
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  • Hachiro HOMMA
    1962 Volume 48 Issue 8 Pages 953-959
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    To select the induction hardening steels, the author studied the effect of the nonmetallic inclusions on the sensitivity to induction-hardening crack.
    Namely, making use of the properties of the sulphide inclusions that of shape and distribution were changed remarkably by deoxidizing method in the steel melting, the author had prepared many crack test specimens that contained the abovementioned inclusions and various oxides, and examined the crack test by repeated quenching method on the induction hardening.
    The experimental results are summarized as follows:
    (1) The effect of the finely dispersed silicates, alumina and globular or polygonal sulphides in the cast steels on the crack sensitivity was not clear.
    (2) On the contrary, the eutectic type sulphides in the primary grain boundaries gave a distinct effect on the crack sensitivity.
    Namely, about 0·1% (area ratio) or more of the entectic sulphides increased the crack sensitivity with the 0·72%C cast steel.
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  • Studies on tempering process of the γ type heat-resisting alloys-VI
    Tsuyoshi MASUMOTO
    1962 Volume 48 Issue 8 Pages 959-967
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    An unknown phase, which had been, detected in the aged LCN-155 type alloys and temporarily designated as “X”, was examined and discussions were made on the cor-relation with the additional elements such as C, N, Mo, W and Cb, the precipitate reaction in alloy during aging, the X-ray diffraction pattern, the lattice parameter, the specific gravity, and the chemical composition.
    As the results, it was concluded that an unknown phase in the LCN-155 type alloys should be the new secondary phase unlike the well-known phases such as M23C6, M6C and η′ phase.
    Further, a model of crystal structure was presented for the new phase. It was presumed that this phase, which was newly named as “π”, might be the carbo-nitride compound having the following crystal structure:
    Symmetry……Cubic
    Space group……Fd 3 c
    Unit cell dimension……a0=10·70-10·75Å
    Number of atoms per unit cell……104
    Chemical formula……M11 (C, N) 2
    (Cr, Co, Ni, Fe) 8 (Mo, W) 3- (C, N) 2 in the LCN-155 type alloy.
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  • Toshimi YAMANE
    1962 Volume 48 Issue 8 Pages 967-971
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    The erosion of mild steel has been studied by E. J. Daniels in detail, but it was not understandable what composition steel should be used. There is an opinion that one should use a deoxidized and high-tensile strength steel plates such as boiler plates for zinc dipplating kettles. However, concerning the erosion by molten zinc bath, it is not always good to use such kinds of steel plates. It happens sometimes that a good erosion resistance to molten zinc bath is proved when an old steel plate is used which has been made by an inexperienced steelmaking technique. These are influenced by many factors. In this experiment, the author investigated the influences of carbon, manganese, silicon contents in steel plates, the deoxidation of steel, the molten zinc bath temperature and effects of aluminum addition in the zinc bath.
    Experimental results show that a low-carbon steel plate shows a good erosion resistance molten zinc, and about 0·1%C steel is good for the practical use, and a deoxidized steel shows good erosion resistance to molten zinc bath. On the contrary, a high-silicon or a highmanganese steel shows bad results, while aluminum-deoxized steel shows a good erosion resistance.
    Molten zinc bath is erosive to iron at near 500°C, for there is a peritectic reaction in the Fe-Zn diagram. It is desireable to operate dig-plating at a low temperature of 450°C for the long use of the dip-plating kettle.
    The erosion of steel plates in molten zinc is decreased by about 1/2 at the same temperature in the case of the 0·2% aluminum addition in molten zinc as comparted with a simple zinc bath.
    Stainless steels shows a good erosion resitance but it can not be used from the economical point of view.
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  • Michira UCHIYAMA
    1962 Volume 48 Issue 8 Pages 972-982
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • Yataro NISHIYAMA
    1962 Volume 48 Issue 8 Pages 983-989
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • Kokichi SANO
    1962 Volume 48 Issue 8 Pages 990-999
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • [in Japanese], [in Japanese], [in Japanese], [in Japanese], [in Japane ...
    1962 Volume 48 Issue 8 Pages 1000-1004
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • 1962 Volume 48 Issue 8 Pages 1007-1008
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Download PDF (534K)
  • 1962 Volume 48 Issue 8 Pages 1009-1011
    Published: July 01, 1962
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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