Tetsu-to-Hagane
Online ISSN : 1883-2954
Print ISSN : 0021-1575
ISSN-L : 0021-1575
Volume 70, Issue 1
Displaying 1-18 of 18 articles from this issue
  • Motoh ASAKAWA, Hisayoshi HAMAMATSU
    1984 Volume 70 Issue 1 Pages 16-22
    Published: January 01, 1984
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    Download PDF (1224K)
  • Junichi TANAKA, Mamoru SATO
    1984 Volume 70 Issue 1 Pages 23-36
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (5889K)
  • Yoshikazu TAKAHASHI, Reijiro AKAHASHI
    1984 Volume 70 Issue 1 Pages 37-42
    Published: January 01, 1984
    Released on J-STAGE: February 15, 2010
    JOURNAL FREE ACCESS
    Download PDF (1154K)
  • Tetsu NISHI, Hiroshi HARAGUCHI, Yoshiaki MIURA
    1984 Volume 70 Issue 1 Pages 43-50
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    The deterioration of coke in the blast furnace was taken as the change in coke size with the reaction between the coke and CO2 gas. To clarify this reaction mechanism, a series of experiments were carried out, using apparatus for measuring coke strength after CO2 reaction. The findings obtained are as follows:
    (1) The process of progress of the reaction between the coke and CO2 gas can be analyzed by a single-particle model.
    (2) As a result, a homogeneous-phase model or an unreacted-core model may be considered to represent the reaction type of lump coke.
    (3) When coke contains a large amount of isotropic textures, the reaction proceeds at the surface. The type of this reaction is close to that represented by the unreacted-core model.
    (4) When coke has a high porosity, the CO2 gas permeates the inside of coke lump along the pores. The type of this reaction is close to that represented by the homogeneous-model.
    (5) The difference between these two types of reaction depends on the matrix nature and structure of coke.
    (6) Based on the above findings, the conditions required of coke that is not readily reduced in size by CO2 gasification are proposed.
    Download PDF (1301K)
  • Takahiro FUKUDA, Fumio NAITO, Masataka HIMEDA, Tetsuro SUETAKI, Michit ...
    1984 Volume 70 Issue 1 Pages 51-57
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    For the efficient blast furnace operation, a computer system having following functions was developed and has been used in Hirohata works.
    (1) Control function of gas flow distribution : The accuracy of gas flow detection can be improved by this function, and the efficient gas utilization has been achieved.
    (2) Control function of heat balance : This function consists of estimation model and operational guide for heat balance operation, and it helps stabilization of hot metal quality.
    (3) Prevention function of abnormal condition : The abnormal condition can be forecasted and prevented by this function, and the stable condition in blast furnace has been obtained.
    (4) Function of operation analysis : This function supports other functions by rapidly analysing operational data.
    These functions have been refined according to the change of circumstances successively, and contributing to efficient blast furnace operation.
    Download PDF (1237K)
  • Hiroshi SAITO, Akinori YOSHIZAWA, Tanekazu SOMA
    1984 Volume 70 Issue 1 Pages 58-64
    Published: January 01, 1984
    Released on J-STAGE: February 15, 2010
    JOURNAL FREE ACCESS
    Average mass transfer between an impinging laminar jet of gas and a liquid surface in a crucible was studied.
    The experiments were carried out in the following systems;
    a) H2O (1)-CO2 (g), C2H5OH (l)-H2 (g) and H2O (l)-CO2 (g) systems with known diffusion coefficients DAB (m2/s) near room temperature (1060°C),
    b) FeCl2-(l)-N2 (g) system with unknown diffusion coefficient in high temperature (700930°C).
    (1) For the average Sherwood number Sh (≡kdc/ DAB), the correlation was obtained as
    Sh=m (rc/d)-1Re0.87 Sc0.66, (m= 0.56 ± 0.06)
    by the experiment on systems a) under condition;
    4≤Re≤800, 0.5≤Sc≤1.24, 3.17≤(rc/d)≤9.5.
    (2) For the system b), Sh could also be expressed by the above equation above for 20≤Re≤200, rc/d= 2.42.
    (3) Temperature dependence of the diffusion coefficient of FeCl2 (g) in N2 (g) for 700 to 930°C, 1 atm was obtained as
    DFeCl2- N2=a (T/273)2.0×10-4, (a= 0.31±0.01) (m2/s)
    based on the similarity between experiments a) and b) for gas-phase mass transfer.
    Download PDF (946K)
  • Shiro BAN-YA, Nobutoshi MARUYAMA, Yukio KAWASE
    1984 Volume 70 Issue 1 Pages 65-72
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    The vapor pressure of phosphorus on liquid Fe-P-j (j=Ti, V, Cr, Mn, Co, Ni, Cu, Nb, Mo, or W) alloys has been measured by the transportation method at 1 673K.
    The results obtained are treated by the model of interstitial solution proposed by J. CHIPMAN, and the effects of alloying elements on the activity coefficient of phosphorus in liquid iron are determined by assuming that all the alloying elements studied in the present work are substitutional.
    The interaction parameters obtained in this work are summarized as follows:
    εTlP=-11.0±2.1, εVP=-8.67±2.79
    εCrP=-9.34±2.26, εMnP=-7.17±1.16
    εCoP=-1.17±1.04, εNiP=-1.47±0.88
    εCuP=-9.42±2.86, εNbP=-16.1±1.6
    εMoP=-7.26±1.78, εWP=-19.4±3.9
    Download PDF (1210K)
  • Nobuya SHINOZAKI, Kaichiro ISHIDO, Katsumi MORI, Yasuji KAWAI
    1984 Volume 70 Issue 1 Pages 73-80
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Rate of reduction of MnO in slag by liquid iron was studied at mainly 1 600°C. Experiments were carried out with liquid iron containing carbon from 0.8% to saturation and CaO-SiO2-Al2O3 slag containing about 5%MnO. Evolution of CO gas was observed with X-ray technique. Reduction of MnO in slag took place by exchange reaction with iron and reaction with carbon in iron.
    Reaction rate was interpreted by the rate equation derived from the assumption that the reaction was controlled by transfers of reacting components.
    Calculated mass transfer coefficient of MnO in slag was in the same order of the value obtained for the study of rate of transfer of manganese between liquid iron free of carbon and slag. Therefore, it was considered that the stirring of slag phase by CO bubbles was not so intensive.
    Download PDF (3188K)
  • Tadanobu KOMAI, Ikuro NODA, Katsuhiko NORO, Kazuyuki IGA, Jun OSHIDA, ...
    1984 Volume 70 Issue 1 Pages 81-88
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Studies on accumulation of non-metallic inclusion in sub-surface of continuously cast slabs were carried out. Results obtained are as follows:
    (1) Accumulation of alumina cluster in sub-surface of slabs occurs at the stagnant zone of the upward streams from the immersion nozzle in mold. The degree of the above-mentioned accumulation of alumina can be decreased by improving absorption capasity of mold flux.
    (2) Accumulation of alumina cluster in the sub-surface of slabs is caused by entrapping in solidifing shell near the meniscus of alumina, which is carried up to the surface of molten steel in the mold and can not be absorbed enough in the mold flux.
    (3) Argon gas bowing nozzle is effective in reduction of alumina cluster in sub-surface of slabs.
    (4) Degree of surface defects, caused by fluctuation of surface level of molten steel, can be explained by the products of its fluctuation velocity and its fluctuation width.
    Download PDF (2604K)
  • Koshiro TSUKADA, Kazuaki MATSUMOTO, Yoshitaka YAMAZAKI, Kenji HIRABE, ...
    1984 Volume 70 Issue 1 Pages 89-95
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    The plate mill on-line accelerated cooling (OLAC) process is a controlled cooling process characterized by interrupted accelerated cooling in the transformation temperature range after hot-rolling, and subsequent air cooling to room temperature. To optimize production conditions, the effects of rolling conditions, cooling conditions and chemical composition on the mechanical properties of the controlled cooled plates were studied in comparison with controlled rolled (CR) plates. The controlled cooling process could increase strength withont sacrificing toughness, resulting in improved weldability because of decrease in carbon and alloying elements. The beneficial effect was attributed to the fine ferrite and finely dispersed bainite microstructure. The toughness and strength of the controlled cooled plates were determined by the CR conditions before cooling, and the subsequent cooling conditions, respectively. The optimum cooling conditions were as follows : the initial cooling temperature above Ar3, the final cooling temperature ranging from 500 to 600°C, and the cooling rate from 3 to 15°C/s. The controlled cooled plates produced under the optimum conditions had good mechanical properties, equal or superior to those of the CR plates finish-rolled in the (γ+ α) regions, even with the remarkably reduced separation. The production results are also described herein.
    Download PDF (5178K)
  • Kohsaku USHIODA, Mitsunobu ABE
    1984 Volume 70 Issue 1 Pages 96-103
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    In the process of rolling and subsequent annealing, the influence of rolling temperature on the recrystallization texture has been investigated using Fe-0.01 wt% N alloy having the initial grain size of 80μm. Coarsely arranged and wide deformation bands with {110} <001> and {100} <011> orientations are formed after 300°-400°C rolling which is under the condition of dynamic strain aging. Because recrystallized grains with these orientations are preferentially nucleated during annealing at the deformation band, {110} <001> recrystallization textures with a minor intensity of {100} are obtained after annealing. On the other hand, deformation twins formed by-196°C rolling are considered to act as the preferential nucleation site of {211} recrystallized grains and consequently provide {211} <011> recrystallization textures. At other rolling conditions where the formation of deformation bands and deformation twins is not observed, {111} recrystallization textures are developed by the preferential nucleation of recrystallized grains with {111} near existing grain boundaries.
    Download PDF (8819K)
  • Tadaomi FUJII, Kazuo NOMURA
    1984 Volume 70 Issue 1 Pages 104-111
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Temperature dependence of hydrogen diffusivity in as-quenched 2 1/4Cr-1 Mo steel at temperatures of 25 to 300°C was investigated by a glycerine displacement increasing (GDI) method and a electrochemical method. In the determination of residual hydrogen by GDI method, hydrogen was charged at a austenitic temperature range under a hydrogen atmosphere and was discharged in isothermal baths at temperatures of 45 to 300°C.
    1) The hydrogen evolution curves measured by GDI method at 45°C and by a electrochemical method at 25°C in cylindrical specimens agree well with a analytical solution given from Fick's Law.
    2) Measured hydrogen diffusivities in as-quenched 2 1/4Cr-1 Mo steel agree considerably well with the values calculated from a theoretical equation based on a hydrogen trap theory. The apparent hydrogen diffusivity, D, is given as the following equation:
    D=Dl / (1+κ) (cm2/s)
    where, Dl= 7.6×10-4 exp (-2 300/R T) (cm2/s)
    κ= 1.05 × 10-4 exp (7 100/RT)
    R: gas constant
    T: absolute temperature
    Download PDF (1353K)
  • Kiyoshi KIUCHI, Tatsuo KONDO
    1984 Volume 70 Issue 1 Pages 112-119
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Simple and practical countermeasures to intergranular corrosion of normal commercial heats of SUS 304 stainless steels were developed by utilizing the microstructural features of the material aged after plastic deformation without modifying alloy composition. In this method, manufacturing process was modified through full solution treatment and subsequent cold working and aging at carbide precipitation temperature and then heating to recrystallization at temperatures of the levels low enough so that no carbide redissolution takes place.
    In contrast to the traditional mill annealing process, the thermomechanically treated material showed satisfactory immunity to intergranular corrosion. A typical structure obtained by this process is associated with fine crystal grain size and evenly dispersed fine spherical M23C6 type carbide particles.
    In addition to such resistance the material showed improved tensile properties due to the Hall-Petch effect with the refined grain size and the fine carbide dispersion.
    Download PDF (3539K)
  • Yoshitaka IWABUCHI
    1984 Volume 70 Issue 1 Pages 120-127
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    A study has been made of the effect of Ni content on the toughness of low C-13Cr martensitic stainless cast steels containing 4 to 6 percent Ni.
    The main results are as follows:
    (1) The superior toughness is obtained in a specimen tempered at temperature around 600°C.
    (2) Upper shelf energy is a function of the strength, and decreased with increasing Ni content.
    (3) Impact energy in the transition range is determined by the both of strength and reverted austenite content depending on Ni content.
    (4) Increase of Ni deteriorates the toughness as the results of grain boundary embrittlement due to slow cooling from tempering temperature.
    Download PDF (7883K)
  • Nobukatsu FUJINO, Yoshiro MATSUMOTO, Atsuyoshi SHIBUYA, Hideyoku NAKAH ...
    1984 Volume 70 Issue 1 Pages 128-135
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    The Ni-Zn electroplated steel sheet shows good corrosion resistance. On producing this sheet it is important to control the coating weight and the Ni content of alloy film for quality assurance. On line X-ray fluorescence analyzer has been developed for the determination of the coating weight and the Ni content of alloy film.
    The main features of the instrument are as follows:
    (1) Analysis can be done full automatically. (2) The X-ray fluorescence method is used. In the analysis system, X-ray intensities are measured by two detectors (ionization chambers), one is with Fe filter and the other with Ni filter. The coating weight and the Ni content are calculated from the intensities measured by the two detectors. (3) This analyzer is running for about two years without any trouble.
    Download PDF (1334K)
  • [in Japanese], [in Japanese], [in Japanese], [in Japanese], [in Japane ...
    1984 Volume 70 Issue 1 Pages 141-143
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (793K)
  • [in Japanese]
    1984 Volume 70 Issue 1 Pages 144
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (369K)
  • [in Japanese], [in Japanese], [in Japanese], [in Japanese], [in Japane ...
    1984 Volume 70 Issue 1 Pages 145-146,144
    Published: January 01, 1984
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (705K)
feedback
Top