Tetsu-to-Hagane
Online ISSN : 1883-2954
Print ISSN : 0021-1575
ISSN-L : 0021-1575
Volume 49, Issue 6
Displaying 1-15 of 15 articles from this issue
  • [in Japanese]
    1963 Volume 49 Issue 6 Pages 875-876
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • Study on pilot plant of fluidizing reduction-III
    Yoshikazu YAMAMICHI
    1963 Volume 49 Issue 6 Pages 877-882
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    A semi-pilot plant was constructed for development of fluidizing reduction of iron are (inner dia. =350mm: outer dia. =800mm: height=7m.) At first, a triple hearth type which consisted of heating, prereduction and final reduction was operated but abandoned owing to two defects.
    Next, the furnace was reconstructed into a double hearth type. By this reconstruction, steady operation could be assured. By blowing 600°C hot gas, and heating the ore up to 900 °C, good reduction results could be attained. Consumption of coke oven gas was 2, 800Nm3/ton-M. Fe, nearly 1 in terms of gas excess ratio. If cracked gas is used, the consumption of coke oven gas must be 1, 000Nm3/ton-M. Fe.
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  • Studies on hanging of a blast furnace-II
    Koretaka KODAMA, Akitoshi SHIGEMI, Katsuya ONO, Toshimitsu OGATA, Hide ...
    1963 Volume 49 Issue 6 Pages 883-888
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Furnace hanging is possibly caused by flooding. It is confirmed as a result of our experiments by a furnace model and a small scale test blast furnace that the flooding condition in packed column is qualitatively applied to the blast furnace by multiplying the correction coefficient. Coefficients are experimentally evaluated to be 0·5 and 0·35 in case of uniform and mixed coke size respectively. Present blast furnaces are operated nearly at the limiting flooding condition. It may safely be said that the furnace approaches the flooding condition, when the increase of blast volume is frequently accompanied with furnace roughness, slip or hanging.
    Constitutional improvement of blast and more delicate control of burden preparation must be contemplated for increasing the prodution rate.
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  • Takeshi KATO, Kamematsu MATSUDA, Masaru TOKUSHIGE
    1963 Volume 49 Issue 6 Pages 888-894
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Ingot weight of steel has increased as a result of recent mass-production and modernization of the steel plant, with such progress, that the reducing of sulphur segregation in the ingot of rimmed steel became an important problem for maintenance of the quality of steel product.
    We considered that the segregation of sulphur in the ingot was influenced remarkably by the shape of the ingot, and studied many rimmed steel ingots with different shapes, with the following results:
    1) Degree of maximum segregation of sulphur increases with an increasing of the ingot weight, therefore it is necessary to consider the shape of the ingot and pouring pit practices for a large ingot.
    2) Increasing of ingot thickness widens the heavy segregation range of sulphur more than the proportional ratio of ingot shape.
    3) Maximum segregation of sulphur is shifted to ingot top direction by the decreasing of ingot thickness or increasing of the ratio of width to thickness.
    4) It is considered that the heavy segregation of sulphur in rimmed steel ingot results from the rising and coagulation of sulphide during the solidification of molten steel, and that the position and shape of the heavy segregation zone are mainly influenced by the solidifying speed of ingot from top and side to center.
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  • Study on the high-temperature carburizing-I
    Akira ADACHI, Kiyoshi MIZUKAWA, Kakuo KANDA
    1963 Volume 49 Issue 6 Pages 894-900
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Theoretically, there is nothing particularly unusual about the fact that steel carburizes more rapidly at higher temperatures. Higher production rate is obviously possible. With higher temperatures all reaction rates increase but furnace parts erode more rapidly and the grain-size of the steel being treated increases with temperature. The authors experimented on the effect of additional elements especially titanium in carburizing steel on the coarsening temperature of austenitic grain size. The results are as follows:
    (1) Relation between nitrogen and titanium in iron.
    The behavior of titanium nitride in titanium-iron alloys with up to 0·2% titanium was observed on the quenched specimens after equilibrated with the controlled atmosphere at 1560, 1600 and 1650°C. The equilibrium constant in the reaction was determined.
    (2) Effect of titanium on austenitic grain size.
    The effect of titanium compounds on the grain coarsening temperature was studied with titanium-iron alloys containing oxygen, nitrogen or carbon respectively. The results are as follows:
    (A) The grain size was reduced and its coarsening temperature increased by the presence of titanium nitride or carbide. The amount of added titanium required for enhancement of grain coarsening temperature was 0·01 to 0·1%.
    (B) Titanium as solid solution or oxide had not any visible effect on the grain size.
    (C) The steels containing aluminum, zirconium or niobium were superior to the steels containing aluminum or vanadium in the enhancement of grain coarsening temperature.
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  • Study on the quenching effects of oil for steel-I
    Tomo-o SATO, Yoshinori FUJIMURA
    1963 Volume 49 Issue 6 Pages 900-907
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    This paper deals with a study on some properties of oils required for the quenching of steels. Some experiments were carried out on several oils having different properties, using carbon tool steels and low alloy structural steels. This study also treats some remarkable phenomena observed during the quenching as well as the cooling actions of quenching oils.
    The experimental methods are described in detail, together with a preliminary study on the relationship between the hardenability of carbon tool steel and the quenching effects of oil. The following conclusions are obtained:
    (1) The cooling behaviour of carbon tool steels during quenching varies remarkably depending on occurrence or none of pearlite transformation in the steel.
    (2) The presence of gas film generated during quenching is long when pearlite transformation takes place in the surface layer of the test piece.
    (3) The pearlite transformation occurring in the surface layer of a test piece affects remarkably the degree of its hardening.
    (4) The quenching effects of oil on a carbon tool steel differ greatly depending on its hardenability.
    (5) The quenching effects of oil should be examined with respect to steels having different hardenabilities. Proper evaluation of the quenching effects of oil is not obtained using a carbon tool steel having high hardenability.
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  • Taira NAKANO, Shunji YAMAMOTO, Tadataka GOTO, Sadao SUZUKI
    1963 Volume 49 Issue 6 Pages 908-914
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    To investigate the relation of the test piece positions and directions to the mechanical properties of a large sized steam turbine rotor shaft, the authors examined the impact transition temperature and the creep rupture properties of the 1Cr-11/4Mo-1/4V steel high pressure turbine rotor shaft for a 125, 000kW generator with varied positions of test pieces.
    As to the test piece positions, the impact transition temperature rises gradually from the outer part to the center, and the creep-rupture strength at the central portion is higher than that of the outer part because of slower cooling rate; this is in good agreement with other reports. Both the elongation and the reduction of area are higher at the outer portion than those of the central.
    As to the test piece directions, the impact transition temperature of the test piece of radial direction is 10° to 15°C higher than those of longitudinal and tangential direction at each position; however, these transition temperature values, even if at the central portion, satisfy mostly the A. S. T. M. standard value. The creep-rupture strength of the radial or the tangential test piece is lower than that of the longitudinal, the difference between them, however, being comparatively small, with the decrement under 10%.
    Finally comparing the notched specimens with the unnotihed, the former shows a higher creep rupture strength in the short time rupture test, and on the contrary a lower value in the long time rupture test, than the latter.
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  • Kiyoshi SEGAWA, Shinichi NAGASHIMA, Shyozo SEKINO, Haruo SHIMADA
    1963 Volume 49 Issue 6 Pages 914-920
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Bekanntlich, der Stahl mit 9% Ni zeigt gute Kerbschlagzähigkeit bei sehr niedriger Temperatur unter-190°C.
    Es unterliegt keinem Zweifel, daß das bei Abschrecken und Anlassen aufgetretene Austenit darüber eine groäe Rolle spielt.
    Jedoch, der ausführliche Mechanismus löst sich bisher nicht auf. Um diesen Mechanismus aufzulösen, wurde zunächst Austenit elektrolytisch isoliert und eingehend untersucht. Infolgedessen, wurde es festgestellt, daß Austenit durch die Verwendung des Elektrolyts, 5%Na-zitrat+1·2%KBr+HCl (PH: 5), vollkommen isoliert werden konnte. Da dieses isolierte Austenit geringes zementit begleitete, wurde Austenit untersucht, sowohl durch die chemische
    Analyse, als auch durch die magnetische Analyse. Daraus wurde es gefunden, daß Nickel im Austenit als im Grundmasse sich anreicherte. Auöerdem wurde es auch vermutet, daß Mangan und Kohlenstoff im Austenit sich anreicherten.
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  • Takao SASABE
    1963 Volume 49 Issue 6 Pages 921-927
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • Toshihiko ASAKUMA, Tetsuya WATANABE
    1963 Volume 49 Issue 6 Pages 928-942
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • CHARLES GOODEVE
    1963 Volume 49 Issue 6 Pages 943-946
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • CHARLES GOODEVE
    1963 Volume 49 Issue 6 Pages 947-948
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • [in Japanese], [in Japanese], [in Japanese], [in Japanese], [in Japane ...
    1963 Volume 49 Issue 6 Pages 957-960
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
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  • 1963 Volume 49 Issue 6 Pages 963-964
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Download PDF (459K)
  • 1963 Volume 49 Issue 6 Pages 965-966
    Published: June 01, 1963
    Released on J-STAGE: February 22, 2010
    JOURNAL FREE ACCESS
    Download PDF (651K)
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