Journal of the Japan Institute of Metals and Materials
Online ISSN : 1880-6880
Print ISSN : 0021-4876
ISSN-L : 0021-4876
Volume 31 , Issue 6
Showing 1-20 articles out of 20 articles from the selected issue
  • Jun-ichiro Yagi, Hiroaki Nishio, Keiichi Sasaki, Iwao Muchi
    1967 Volume 31 Issue 6 Pages 711-716
    Published: 1967
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The over-all reaction rate Eq. (8) of the reaction between cokes and steam is derived, considering the steps of the diffusion through a gaseous film, intraparticle diffusion and chemical reaction. Considering that the rate of reaction between CO and steam is very fast and that gas flow is almost completely turbulent in the blast furnace, it has been assumed that the equilibrium of this reaction holds in the gas phase in the blast furnace. The over-all reduction rate of the iron oxide with hydrogen is given as Eq. (6), neglecting the effect of adsorption of water vapor.
    Our model(3) reported already has been modified here by addition of three reactions mentioned above and the boundary conditions of our new model have been calculated by means of the over-all heat and material balances and operating conditions.
    Using this improved model, the axial distributions of temperatures of gas and particles, volume rate of flow of gas, compositions of CO, CO2 and H2, fractional conversions of iron and of limestone, density of gas, bulk density of particles and gaseous pressure under practical operating conditions in the blast furnaces have been determined numerically by a disital computer. The calculated results are illustrated in Figs. 4 and 5.
    It has been confirmed that the calculated results agree well with the values reported by Shürmann(18).
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  • Hiroshi Takechi, Hiroshi Kato, Tatsuya Sunami, Tadashi Nakayama
    1967 Volume 31 Issue 6 Pages 717-723
    Published: 1967
    Released: April 04, 2008
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    A model which can explain the ridging phenomenon in 17%-chromium stainless steel sheets was proposed and examined experimentally. It can be proved that the ridging phenomenon has an origin in shear strain of the texture which has the [011] axis in the rolling direction. Although the ridging phenomenon has been believed to occur only after working, in the present study, it was observed even in the cold-rolled sheets.
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  • Yoshitaka Nakagawa, Koreaki Suzuki, Akitsugu Momose
    1967 Volume 31 Issue 6 Pages 723-728
    Published: 1967
    Released: April 04, 2008
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    The viscosity of Fe-C-Si alloy (3.5%C, 1.20%Si) was measured by an apparatus which uses the oscillating crucible method, in order to investigate the presence of hysteresis and the difference in viscosity between white and grey iron melts of the same chemical compositions. The results obtained were summarized as follows: (1) Viscosity curves measured during the superheating process did not correspond with those during the cooling process in the temperature range of 1255° to 1480°C, and negative hysteresis was recognized. The higher the maximum heating temperature, the more wider became the width of hysteresis. (2) In this temperature range the viscosity of grey iron was higher than that of white iron. (3) In case of holding the melt at 1342° and 1288°C, the change of the viscosity coefficient with time decreased rapidly until 20 minutes of holding. Even after the further elapse of time, the difference between white iron and grey iron melt was clearly recognized, showing that the viscosity of the latter was higher than that of the former. (4) With increasing Si content up to 0.43%, the hysteresis was hardly recognized, but over 1.22%Si there appeared negative hysteresis. In both superheating and cooling processes the viscosity showed a maximum value at 1.22%Si and a minimum value at 0.43 and 2.70%Si, respectively.
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  • Mayumi Someno, Kyuya Nagasaki, Kunio Kadoi
    1967 Volume 31 Issue 6 Pages 729-734
    Published: 1967
    Released: April 04, 2008
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    The solubility of hydrogen in liquid iron and in its binary alloys with aluminium, cobalt, chromium, germanium, molibdenum, nickel, silicon, tin and vanadium has been determined by Sieverts’ method at 1 atm pressure of hydrogen. Interaction parameters eH(i) for iron-i alloys are determined and compared with the available data.
    The results obtained are summarized as follows:
    (1) Solubility of hydrogen in liquid iron over the temperature range of 1540°∼1700°C:
    (This article is not displayable. Please see full text pdf.)
    (2) Interaction parameter eH(i) in liquid iron alloys:
    (This article is not displayable. Please see full text pdf.)
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  • Norio Nagata, Susumu Yoshida
    1967 Volume 31 Issue 6 Pages 735-740
    Published: 1967
    Released: April 04, 2008
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    The dynamic deformation behaviours of copper single crystals (99.999% purity) and polycrystals (99.99% purity) were investigated by compression tests at room temperature and partly at liquid nitrogen temperature, using a bar-bar type impulsive loading apparatus. Strain rates studied were of the order of 102∼103 sec−1 for the dynamic test and 10−4∼10−2 sec−1 for the static test.
    The time variation of the observed stresses at both ends of a specimen under dynamic test definitely shows the effect of plastic wave propagation. Crystals with orientations ranging from the middle to the [110]-[111] boundary in the stereographic triangle show higher critical resolved shear stresses and flow stresses and more extensive regions of stage I, followed by definite regions of stage II, under dynamic deformation than those under static deformation. The rates of work-hardening of stages I and II are shown to be independent of strain rate. The strain rate dependence in the stress-strain relations for crystals with orientations near [100] and polycrystals is negligibly small. Microscopic observations show that there is no remarkable difference in slip markings between the dynamically deformed specimen and the statically deformed one.
    It is concluded from the above results that for a high strain rate deformation of copper single crystals, the influence of the frictional stress on moving dislocations becomes too large to be negligible, if the dislocation density of the specimen is fairly small.
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  • 1967 Volume 31 Issue 6 Pages 740
    Published: 1967
    Released: April 04, 2008
    JOURNALS FREE ACCESS
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  • Taichi Kamijo
    1967 Volume 31 Issue 6 Pages 741-746
    Published: 1967
    Released: April 04, 2008
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    Copper polycrystalline aggregates with (001)[110] and (001)[100] orientations were cold-rolled up to 96.7 pct and annealed for 30 min at 250°C to examine the inverse Rowland mechanism. On annealing a simple {112}⟨111⟩ rolling texture which is formed after 75 pct rolling of the (001)[110] orientation, no cube texture can be observed. With increasing the amount of the {011}⟨211⟩ or the {123}⟨211⟩ component of the rolling texture, the intensity of the cube texture component increases at higher reduction. In case of the (001)[100] orientation, a fairly sharp cube texture is developed from a rolling texture which scarcely contains the {112}⟨111⟩ component. It is clear that these results are not in good accordance with the expection derived from the inverse Rowland mechanism.
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  • Moriya Ohyane, Hideo Sekiguchi
    1967 Volume 31 Issue 6 Pages 746-752
    Published: 1967
    Released: April 04, 2008
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    The effect of deformation rate on the behavior of recrystallization has been studied with pure polycrystalline iron, compressed 60 pct at two widely different rates. Within the temperature range of 600° to 650°C, the isothermal recrystallization curves of the dynamically deformed iron (impact velocity, 12 m/sec) and the statically deformed iron (crosshead speed, 10 mm/min) are obtained. The recrystallization rate after dynamic deformation is considerably smaller than that after static deformation. However, at the beginning of the annealing process, it seems that the nucleation rate of recrystallization of the dynamically deformed iron is larger. The activation energy for recrystallization of the dynamically compressed iron is larger by 40 pct than that of the statically deformed one.
    It is also investigated that there are the differences of the work-hardening and the microstructure between the dynamically deformed iron and the statically deformed iron.
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  • Kaizo Monma, Hajime Suto, Masayoshi Fujita, Yoshihiko Kubomura
    1967 Volume 31 Issue 6 Pages 753-757
    Published: 1967
    Released: April 04, 2008
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    The effects of ausforming on the mechanical properties of 0.2%C-3%Ni-2%Mo steel were examined. As is generally known, the yield strength increased by ausforming. The hardness and tensile strength of ausformed steel changed in a manner parallel to those of conventionally quenched steel with increasing tempering temperature and showed a clear secondary hardening. The size of θ and Mo2C particles in ausformed steel was smaller than that in conventionally heat-treated steel. The θ-phase in conventionally heat-treated steel shows a Widmanstätten structure. On the other hand, the θ-phase in ausformed steel precipitates also preferentially on the transformation twins formed by ausforming. When the holding time between ausforming and quenching was prolonged, recovery occurred and the effect of ausforming also decreased. But it appears that recrystallization did not occur during the period between ausforming and quenching even at 800°C.
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  • Kaizo Monma, Hajime Suto, Norihiko Kikuyama
    1967 Volume 31 Issue 6 Pages 758-761
    Published: 1967
    Released: April 04, 2008
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    Iron and 0.2%C-steel specimens containing zero%, 3% and 5% nickel were tested and the effect of nickel on the low temperature brittleness of iron and steel was discussed. It was found that by alloying nickel, the brittle-fracture strength of iron was not affected, but the yield strength was decreased, the deformation twin was suppressed, and the ferrite grain was refined. These characteristics of alloying nickel may contribute to the low temperature toughness of iron and steels.
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  • Genjiro Mima, Sigeoki Saji
    1967 Volume 31 Issue 6 Pages 761-766
    Published: 1967
    Released: April 04, 2008
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    Precipitation in a Cu-2.3 wt%Fe alloy was observed by transmission electron microscopy. In the specimens quenched into ice water after solution treatment, dislocations and dislocation loops were observed, but precipitation was not found. The characteristic contrast images were observed in the specimens aged for 18 min, 28 min, 160 min and 45 hr at 650°C, and each contrast image seems to be due to the elastic strain in the matrix around a spherical coherent precipitate particle. The diameter of the precipitate particles in the above-mentioned specimens were about 50 Å, 110 Å, 200 Å and 430 Å, respectively. In the specimens aged for 120 hr at 700°C, the precipitate particles were about 1000 Å in diameter, around which interfacial dislocations, moiré patterns, and usual glide dislocations generated from the particles were observed. The particles in these specimens would be quasi-coherent or non-coherent. A number of tangled dislocations were observed at the periphery of the non-coherent particles in the specimens aged for 340 hr or 1000 hr at 700°C. The spherical particles indicated a fcc structure. The spherical particle-free regions or elongated discontinuous precipitates were found in a limited area along grain boundaries in some aged specimens. The discontinuous precipitates were seldom observed within the grain and had a fcc structure. Homogenious precipitation occurred in the specimens which were cold-rolled to 6% or 28% reduction after the solution treatment and then aged 160 min at 650°C. In the specimens, cooled from 1050°C to 900°C or to 800°C in the furnace and then quenched, precipitates in peculiar shape were observed. They appeared to grow three-dimensionally in some of ⟨100⟩ and ⟨110⟩ directions and had a fcc structure.
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  • Hiroshi Yada, Takayuki \={O}oka
    1967 Volume 31 Issue 6 Pages 766-771
    Published: 1967
    Released: April 04, 2008
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    The growth of bainite relief in Fe-6%Ni-alloys with various carbon contents was studied by hot-stage microscopy, and its edgewise growth rate was determined over the temperature range 200°∼500°C. The results are as follows: (1) The dependence of the growth rate both on temperature and carbon content is consistent with the prediction from the theory that the growth rate of bainite is controlled by the diffusion of carbon in austenite near the austenite-ferrite interface. (2) The values of the growth rate obtained are always about 1/30 of the corresponding values predicted from the above theory for the iron-carbon system. This difference can be largely attributed to the effect of nickel on the equilibrium content of carbon in austenite at the austenite-ferrite interface. (3) In comparison with the other results published so far, the growth rate of bainite appears to decrease exponentially with the nickel content at the same temperature and carbon content.
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  • Hiroshi Yada, Takayuki \={O}oka
    1967 Volume 31 Issue 6 Pages 771-776
    Published: 1967
    Released: April 04, 2008
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    In order to clarify the processes of bainite reaction, an Fe-6%Ni-0.6% carbon alloy, transformed for a short time at 300°C and 450°C isothermally and then quenched into water, was examined by transmission electron microscopy. The results are as follows: (1) The growing edge of the bainite plate is low carbon ferrite with lower dislocation density and with no precipitation in it. This fact supports the conclusion obtained by the same anthors in the preceding paper. (2) At 300°C plane faults parallel to {123}α were observed at the growing edge. These faults are considered to be formed due to the sidewise growth of bainite in the form of thin ferrite plates. Ribbon-shaped cementites nucleate at the ends of these faults, with the habit plane of {112}α. (3) At 450°C, cementites first precipitate at the sides of ferrite plate directly from austenite. These cementite plates, parallel to {112}α, are then converted into rod-shaped cementites with a long axis parallel to the ⟨111⟩α direction. (4) Selected area diffraction patterns show the same orientation relationship between ferrite and cementite as Pitsch-Schrader’s at 300° and 450°C.
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  • Yunoshin Imai, Tsuyoshi Masumoto, Mitsuru Watanabe
    1967 Volume 31 Issue 6 Pages 776-781
    Published: 1967
    Released: April 04, 2008
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    The polarizing characteristics of synthesized intermetallic compounds, FeCr, Fe36Cr12Mo10, Fe7Mo6, Fe2Ti, NiAl, Ni3Al and Ni3Ti, were studied by means of a potentiostat in order to determine the electrolytic conditions for isolating or etching the intermetallic compounds in the alloys. From the measurement of polarization curves of the compounds, some useful information was obtained as to the electrolyte and the electrolytic potential for isolating or etching.
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  • Seiichi Karashima, Hiroshi Oikawa, Tadashi Hasegawa
    1967 Volume 31 Issue 6 Pages 782-787
    Published: 1967
    Released: April 04, 2008
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    Structual changes in copper during high-temperature creep deformation were investigated by means of the Berg-Barrett method and transmission electron microscopy.
    In single crystals oriented for single slips, subgrains elongating parallel to the deformation band have been found at an early stage of transient creep. With the progress of deformation they were cut parallel to slip lines, resulting in square blocks (200∼300 μ in size), which covered almost the whole specimen surface at an early stage of steady-state creep. During steady-state creep these square subgrains were subdivided into smaller ones (50∼100 μ). Misorientation within the square subgrains and disorientation in their sub-boundaries increased very rapidly during transient creep, but remained almost constant throughout the steady-state region. On the other hand, misorientation within the smaller subgrains increased with increasing strain in the steady-state region.
    In single crystals oriented for multiple slips, subdivision into small subgrains began at an early stage of creep and complex substructure eventually developed.
    In polycrystalline specimens, the subgrain size subjected to creep deformation was generally small compared with single crystals. Fragmentation of a grain into a few blocks perhaps due to interactions with neighbouring grains was also observed.
    In transmission electron microscopy, sub-boundaries parallel to slip plane (111) and to deformation band (110) were mainly observed, which were generally composed of more than two sets of dislocations. However, dislocation pile-ups to substantiate the X-ray finding which might suggest that substructure developes through the formation of deformation bands have never been observed.
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  • Tsutomu Iimura, Susumu Kurokawa
    1967 Volume 31 Issue 6 Pages 787-788
    Published: 1967
    Released: April 04, 2008
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  • Noboru Takahashi, Teruzô Shimizu
    1967 Volume 31 Issue 6 Pages 789-793
    Published: 1967
    Released: April 04, 2008
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    In order to study the deformed superficial layers produced in 18-8 stainless steel by abrasion with emery paper, superfinishing, finishing with polishing cloth, etc., one side of a foil of 18-8 stainless steel of 0.15 mm thick was abraded, thinned by electropolishing from the other side which was not abraded, and examined by transmission electron microscopy.
    In the case of abrasion with emery paper, stacking fault ribbons and slip lines were observed as the result of the movement of deformation dislocations. C.p.h. ε-phase martensite was formed by transformation due to abrasion and the movement of dislocations was hindered by thin plates of ε-phase martensite. α-phase martensite was observed in crystallites produced by promoted grinding, showing bcc Debye-Scherrer diffraction rings.
    In the case of superfinishing, the deformed superficial layer was composed of crystallites of α-phase, but its thickness was much smaller than in the case of abrasion with emery paper. Stacking fault tetra hedra were observed sometimes.
    These results show that a deformed superficial layer is produced even by light abrasion and that there exists superficial work hardening. It is concluded that the essence of a finishing operation of a metallic surface consists in plastic deformation in a thin layer in the atmosphere of heating at high temperatures and successive quenching.
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  • Yoshimoto Wanibe, Kôkichi Sano
    1967 Volume 31 Issue 6 Pages 795-801
    Published: 1967
    Released: April 04, 2008
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    The present work was aimed to study the growth of the alumina inclusions forming a layer-like inclusions group and to investigate their distribution. So the experiment was carried out to drop an aluminum bar onto the static liquid iron containing oxygen, and the alumina inclusions formed during deoxidation were observed by the microscope and extracted by the iodine-alchol method. The results are summarized as follows:
    (1) As the inclusions grew dendritic, the long diameter, l and the short one, d, were measured by the microscope and were summarized by the initial oxygen content in the liquid iron and the reaction time. The results show that the inclusions are growing along the approximate equation, l=1470d2 (cm) (d and l>1×10−3 cm).
    (2) In the specimens containing the initial oxygen content of about 0.05% in the liquid iron, a few of the largest alumina inclusions, the position of which was reasoned not to change, were measured and the growth mechanism of the inclusions was discussed. So the mechanism can be explained successfully by the diffusion of an alumina molecule.
    (3) The extraction experiments show that the alumina inclusions increase in number and grow with the initial oxygen content and the reaction time. And the effect of the formation of the inclusions group on the decrease of the apparent diffusion coefficient of aluminum into the liquid iron was discussed.
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  • Kunihiro Mori
    1967 Volume 31 Issue 6 Pages 807-811
    Published: 1967
    Released: April 04, 2008
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    The following results were obtained by adding small amounts of various special substances to molten iron of ordinary malleable iron castings.
    (1) Malleable iron castings with spheroidal graphite is obtainable.
    (2) The special substance gives a carbide stabilizing effect to the molten iron. When the special substance is added to the molten iron, the heavy white iron section is obtainable. Because of the high silicon content and spheroidal graphite, the annealing time is shorter and the mechanical properties is better than the ordinary malleable iron castings.
    (3) The mechanical properties of this iron of the ferritic-type are 42 to 50 kg/mm2 in tensile strength, 17 to 21 percent in elongation and more than 150° in bend. The iron of the pearlitic-type has the properties: tensile strength, 77 to 85 kg/mm2: elongation, 2 to 4.5 percent: Brinell hardness, 250 to 280.
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  • Kunihiro Mori
    1967 Volume 31 Issue 6 Pages 812-816
    Published: 1967
    Released: April 04, 2008
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    Properties of Malleable iron castings with spheroidal graphite were investigated. The results were summarized as follows:
    (1) Quenched specimens of the ferritic-type iron was 55 to 48 in Rc scale and that of the pearlitic-type iron was 61 to 63 in Rc scale, but that of black heart malleable iron castings was 18 to 55 in Rc scale.
    (2) This iron showed a better wear resistance than ordinary malleable iron castings, but the dry sliding wear resistance of the ferritic-type iron decreases gradually with the increasing sliding speed.
    (3) The weight loss in specimens after the corrosion test in 2N-HCl solution at room temperature was smaller than ordinary malleable iron castings.
    (4) The impact value is higher than that of ordinary malleable iron castings. This impact value has some relation with the shape of temper carbon.
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