Tetsu-to-Hagane
Online ISSN : 1883-2954
Print ISSN : 0021-1575
ISSN-L : 0021-1575
Volume 69, Issue 10
Displaying 1-20 of 20 articles from this issue
  • Hidetake KUSAMICHI, Toshio MATSUMOTO
    1983 Volume 69 Issue 10 Pages 1215-1228
    Published: August 01, 1983
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    Download PDF (4161K)
  • On the Effects of Alloy Compositions
    Kazumi SHIMOTOR, Tatsuyoshi AISAKA
    1983 Volume 69 Issue 10 Pages 1229-1241
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (1855K)
  • Jun-ichiro YAGI
    1983 Volume 69 Issue 10 Pages 1242-1249
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (1372K)
  • Eiji ISONO
    1983 Volume 69 Issue 10 Pages 1250-1256
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (1283K)
  • Yukio NISHIYAMA
    1983 Volume 69 Issue 10 Pages 1257-1265
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (1780K)
  • Tuneomi ISHIZAKI
    1983 Volume 69 Issue 10 Pages 1266-1271
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (991K)
  • Kyoji SATO, Yasunori NISHIKAWA, Isamu TAMURA
    1983 Volume 69 Issue 10 Pages 1272-1279
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    A hematite sphere of 3.3cm in diameter was reduced by H2 in pressure up to 27 atm at 900°C. The temperature profiles within the solid sphere and the weight change were continuously measured. The experimental results were analyzed by the three interface unreacted-core shrinking model with dynamic effective diffusivity. Influence of gas flow through product layers on the reduction rate elucidated reasonably by using the known structural constants obtained from the permeability and the isobaric diffusion experiments.
    The effect of pressure on the reduction rate was found to be governed essentially by three rate parameters : the effective molecular diffusivity at 1 atm (D°AB) eff', Knudsen diffusivity KA, and chemical reaction rate constant ks. The larger (D°AB) eff' was, the faster reduction rate became and the larger pressure effect became. In the case that ks and KA became larger under the condition of constant (D°AB) eff' the reduction rate increased but the pressure effect decreased. The reduction rate increased with the increase of the pressure, while it became maxmum when the molecular diffusion through the products layers governed the overall reduction rate.
    Download PDF (1406K)
  • Yoshimoto WANIBE, Tatsuya SHIMODA, Koin ITO, Hiroshi SAKAO
    1983 Volume 69 Issue 10 Pages 1280-1287
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    This report presents the elucidation on the reaction of magnesia refractory on molten iron and the refractory transmutation during the deoxidation of iron, based on the investigation of the oxygen concentration in iron melted in magnesia crucibles under Ar atmosphere and reduced pressures, and the examination of the refractory. The results obtained are the various time-dependent behaviors of dissolved oxygen according to differences in crucibles and environmental conditions, together with the growth of the refractory grains, and the particular transmutations of crucibles as to the deoxidation. The successful explanation of these results can be also discussed on the reasonable assumptions.
    Download PDF (5283K)
  • Rokuro SAKAGAMI, Takashi SASAI
    1983 Volume 69 Issue 10 Pages 1288-1295
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    During the repeated cooling and heating of Fe-Si-O alloys (0.07<Si%<0.81) from 1600°C to 1555°C, specimens were sampled from the melt at 1555°C by using Cu sampler, silica tube (inner diameter : 4mm) or silica sampler (10mm). The behavior of the oxide phases formed during solidification of the specimen was reported, with particular attention paid to the distribution and morphology of dendritic inclusion precipitated in the intercellular region of solidified structure. From a qualitative investigation of formation mechanism, it was concluded that very fine silica particles, presumably of several tens angstrom in size, were readily formed in the boundary layer enriched with silicon and oxygen, and the reaction Si+2O = SiO2 proceeded there to equilibrium during solidification, and they were pushed along by the advancing solid and gradually accumulated just ahead of the solid-liquid interface. Silica inclusion was formed by successive adhesion of silica particles to the possible nuclei suspended in the liquid phase after enough accumulation was built up, and the morphology of silica inclusion was strongly influenced by the size of very fine silica particle.
    Download PDF (8020K)
  • Tsuyoshi INOUE, Tetsuo SOSHIRODA, Koji KANEKO, Hisashi TAKADA
    1983 Volume 69 Issue 10 Pages 1296-1302
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    A new rapid spheroidization annealing (RASA) method of wire rod has been developed to complete spheroidization within about 16 minutes. This method consists of two steps. The first step comprises heating rapidly up to a maximum temperature (TM) and cooling down to a temperature below A1 (TH) In the second step, the wire rod is held about 15 minutes at temperature TH. It has been revealed that there is an optimum combination of temperatures TM and TH for each steel to obtain a sufficiently spheroidized structure. The mechanism of RASA method is the same as that of conventional spheroi-dization. There are three different points between the two methods which cause the difference in duration time. First, the new method adopts rapid heating and cooling. Second, temperature TM of the new method is higher than that of the conventional method so as to shorten the austenitizing time. Thirdly, the holding time at temperature TH is shortened to suppress the total time within 16 minutes.
    The strand heat treatment is suitable for this method, because the precise control of wire temperature is essential. The trial of RASA treatment adopting the strand treatment has been performed using gas furnace and induction furnace, and the good upsettability of treated wire has been confirmed.
    Furthermore, the trial production of hexagon headed bolts using RASA treated wire has been done.
    Download PDF (8129K)
  • Kazuo MATSUDO, Takayoshi SHIMOMURA, Koichi OSAWA, Satoshi ONO, Masatak ...
    1983 Volume 69 Issue 10 Pages 1303-1311
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    The effect of phosphorus on the deep drawability of cold-rolled steel sheets was studied by changing carbide morphology before cold rolling and heating rate in annealing. The main results obtained are as follows. (1) In slow-heating annealing, phosphorus improves the deep drawability in the presence of solute carbon and deteriorates the deep drawability in the absence of carbon. (2) In the presence of coarse-carbide, increase in heating rate improves the deep drawability of low-phosphorus steels, but deteriorates that of high phosphorus ones. These results are discussed in detail, taking account of the γ-value and the texture.
    Download PDF (4267K)
  • Osamu SAEKI, Hisashi TAKADA, Masatoshi SUDO, Tsuguaki OHKI
    1983 Volume 69 Issue 10 Pages 1312-1319
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Effects of C, Mn, Ni, Si, and N on structural changes and magnetic properties of cold-worked and heat-treated high manganese non-magnetic steels were studied by means of optical and transmission-electron microscopy, X ray diffraction, magnetic measurement, and Mossbauer spectroscopy.
    Additions of C, Mn, Ni, and Si restrain increase in permeability with cold working. Additions of C and Si accelerate increase in permeability with isothermal annealing at 600°C, and those of Mn and Ni restrain this increase. The increase of the permeability with cold working corresponds to the appearance of strain-induced martensite. The increase of the permeability with isothermal annealing at 600°C is considered to be caused mainly by the ferrite among the pearlitic constituent precipitates. When the amount of ferrite is over 2%, the permeability is above 1.1.
    From these results, it is found that the permeability of steels containing optimum alloying elements such as 0.65%C, 14%Mn, 2%Cr, and 2%Ni remains at a low level under cold working and heat treatment.
    Download PDF (7811K)
  • Manabu TANAKA, Haruhiko FUJITA, Dai FUJISHIRO
    1983 Volume 69 Issue 10 Pages 1320-1327
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Effect of grain size on the high temperature creep deformation has been investigated at temperatures of 873K and 973K on an austenitic steel 21-4N with a large amount of M23C6 carbides as well as on steel SUS304 without precipitates.
    In steel 21-4N, steady-state creep rate decreased with an increase of grain diameter in the range below 100200μ both at 873K and 973K. In the range above this grain diameter, it increased with an increase of grain size at 973K, while it showed the minimum value at 873K. This increase in steady-state creep rate at 973K was associated with the change in the microstructures during creep such as coarsening of grain boundary carbides, formation of ledges and irregularities in grain boundaries. Internal stress during steady-state creep in this steel was almost independent of grain size provided that stress and temperature was constant, and it was primarily related to particle size and interparticle spacing of M23C6 carbides in the interior of the grain.
    In steel SUS304, steady-state creep rate decreased with an increase of grain size, and showed a constant value in the range above about 70μ. This is attributed to a decrease in effective stress (increase in internal stress) with an increase of grain size.
    Download PDF (6833K)
  • Hideharu FUKUNAGA, Tadahisa AKASAWA
    1983 Volume 69 Issue 10 Pages 1328-1335
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Machinability of low alloy steels with extra-low and ordinary sulfur contents was studied by means of turning tests using sintered carbide tools under conventional machining conditions. The results are as follows. Reduction in sulfur contents decreases chip breakability, improves surface roughness and topography at cutting speeds of 100m/min or higher, and exerts only a minor effect on tool life and cutting forces. On the whole, the desulfurized steel can be machined at a high removal rate without any serious problem, provided proper cutting conditions are selected and the smooth machined surface thus obtained promises a good tribological effect.
    It was discussed and found that there was no difference between the mechanisms accounting for the effects of desulfurization and those of resulfurization on the machinability of steel.
    Download PDF (5307K)
  • Masato ENOMOTO
    1983 Volume 69 Issue 10 Pages 1336-1343
    Published: August 01, 1983
    Released on J-STAGE: February 16, 2010
    JOURNAL FREE ACCESS
    The generalized central atoms model of multicomponent interstitial solutions is placed in a form which permits direct application to the calculation of α-γ phase boundaries in dilute Fe and Fe-C base multicomponent alloys. Example calculations are made of the ortho and paraequilibrium boundaries in the systems containing two species of substitutional alloying elements in which experimental data on carbon activity, equilibrium tie-line and/or phase boundaries are available. The calculation can be readily extended to the systems containing more than two species of alloying elements. It is expected that the use of this model facilitates the evaluation of thermodynamics of α-γ transformation in steel.
    Download PDF (1366K)
  • Yoshiharu OHASHI, Yasuko FURUNUSHI, Kozo TSUNOYAMA
    1983 Volume 69 Issue 10 Pages 1344-1349
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Grimm-type glow discharge spectrometry (GDS) utilizing both sub-and pre-discharge techniques is capable of providing a rapid and accurate method for determining the elemental composition of iron and steel surfaces, and also for determining in-depth concentration profiles in thin surface layer (within 1000Å from surface). By using GDS with the preliminary discharge technique (modified GDS), the influence of abnormal fluctuation at the first stage of discharge was completely excluded, and the unstable region of the intensity profile at the beginning of discharge was restricted to 10Å or so. This modified GDS provides a means for measuring the correct depth profile at the uppermost surface layer of steels, and also provides the capability for an important application of GDS to surface analysis.
    Download PDF (1102K)
  • Minao ITO, Minoru YANAGYIDA, Hiroshi FUSHIDA, Masanao NARITA
    1983 Volume 69 Issue 10 Pages 1350-1357
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    On rapid determination of total, acid soluble and insoluble contents of aluminium in steel by emmision spectrochemical method with pulse height distribution analyzer, it was made clear that each intensity of pulse distribution was composed of several factors, such as soluble and insoluble aluminium, interfering elements and background, and that influence degrees of these factors change with pre-spark pulses and kind of intensity. Among these factors, influence degree ratio of insoluble to soluble aluminium changed from 1.47 to 3.05 in this study. This fact was the cause of error in using one intensity method. In order to eliminate this error, the ratio should be corrected by using two intensities which are different in the ratio. Good accuracy for determining total, soluble and insoluble aluminium was obtained by using 40% and 70% intensities at 2 000 pre-spark pulses. It was also found on standardization method of this two-intensity method that coefficient ratio for two intensities of calibration equation can be considered constant and that almost the same standardization method as one-intensity method can be used.
    Download PDF (1400K)
  • [in Japanese], [in Japanese]
    1983 Volume 69 Issue 10 Pages 1358-1359
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (416K)
  • [in Japanese]
    1983 Volume 69 Issue 10 Pages 1359-1359,1366
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (452K)
  • [in Japanese], [in Japanese]
    1983 Volume 69 Issue 10 Pages 1360-1365
    Published: August 01, 1983
    Released on J-STAGE: June 30, 2009
    JOURNAL FREE ACCESS
    Download PDF (1393K)
feedback
Top