Journal of the Japan Institute of Metals and Materials
Online ISSN : 1880-6880
Print ISSN : 0021-4876
ISSN-L : 0021-4876
Volume 39 , Issue 9
Showing 1-17 articles out of 17 articles from the selected issue
  • Yoshiharu Mae
    1975 Volume 39 Issue 9 Pages 889-893
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Es ist bekannt, dass Bleche aus Titanlegierungen sich mit zunehmendem R-Wert texturverfestigen.
    Der Einfluss des R-Wertes auf die Biege-, Streckzieh-und Tiefziehfähigkeit wurde schon berichtet. Hier wurde der Einfluss des R-Wertes auf den Fliessort und den Mechanismus der Rissbildung beim Streckziehversuch wie Erichsen-Tiefungsversuch untersucht.
    Die Ergebnisse sind in folgender Weise dargestellt.
    (1) Der aus der Knoop-Härte ermittelte Fliessort stimmt mit der Hillschen Theorie ziemlich gut überein. Mit zunegmendem R-Wert nimmt die Anisotropie des Werkstoffs zu und der Werkstoffs texturverfestigt sich im Zug-Zugbereich.
    (2) Aber es ist nicht immer richtig, aus obigem Fliessort die Bruchspannung unter dem Komplex-Spannungszustand zu schätzen.
    Der Grund ist, dass der Riss unter wesentlich kleinerer Spannung als die Fliessspannung im örtlichen formänderungskonzentrierten Bereich leicht auftritt, weil sich die Form des Risses vom echten Scher-Typ zum Normalspannungsbruch verändert, infolgedessen die Umformbarkeit abnimmt.
    (3) Mit der Theorie für plastische Instabilität kann man über den Einfluss des R-Wertes auf die Streckziehgrenze unter solchen Bedingungen nicht erklären, dass sich Bruchszustand verändert. Mit diesen Versuchsergebnissen stimmt die Theorie von Kikuma, die den Bruchmechanismus berücksichtigt, gut überein.
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  • Ryoichi Urao, Kazuo Nakajima, Tadashi Chihaya
    1975 Volume 39 Issue 9 Pages 894-898
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Some kinds of metals are hardened by ion-bombarding with the reactive gas in glow discharge. This technique is being applied to surface hardening of some metals. In most cases, however, metals have been hardened by ion-nitriding using a nitrogen-hydrogen gas mixture as a bombarding gas. In this work iron and some steels were bombarded in the city gas (the reformed naphtha which have a combustion heat of 3600 kcal/m2) in the temperature range from 400 fo 700°C in order to ion-carbo-nitriding. The gas seems to be useful for carbo-nitriding, because it consists of CH4, CO, CO2, N2, H2, H2O, etc. The change on ion-bombarded specimens were investigated by means of optical microsrcopy, hardness measurement, X-ray analysis, etc. The following results were obtained.
    In α-iron and S 15 C steel, the surface layers of cementite are formed at 650 to 700°C and their maximum hardnesses are higher than Hv 1000.
    In SCM 21 and SACM 1 steels, the same layer is not observed clearly by the optical microscope but the reflections from the cementite are obtained on X-ray diffraction. They are soft in comparison with α-iron and S 15 C steels.
    SUS 304 steel could not be carbo-nitrided.
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  • Toshiro Suhara, Kazunori Kitajima, Shigehisa Fukuda, Hiroshi Ito
    1975 Volume 39 Issue 9 Pages 899-903
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    This paper describes the measurements of adhesive strength and metallographic observations of coating films obtained by means of wire explosion spraying, together with some considerations on the mechanisms producing the adhesive bonds on mild steel substrate. The sprayed materials were tungsten, molybdenum and piano wire. The critical shearing stresses of adhesion measured by the shearing test specially designed, ranges in 17∼26 kg/mm2 in the case of tungsten and molybdenum and about 25 kg/mm2 in the case of high carbon steel coated on the substrate of mild steel. These values are about 5 times as large as those obtained by flame spraying. The mechanism of adhesion of coating to mild steel substrate is studied in the case of tungsten coating. The high strength of adhesion is attributed to the formation of welded zone between coating and substrate which is observed by electron microscope and electron probe X-ray microanalyser (EPMA). The mechanisms are explained by means of high impinging velocity and high temperature of sprayed particles which are characteristics of wire explosion spraying. Theoretical considerations attempt to explain the mechanisms of formation of the structures and the adhesion properties.
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  • Hirofumi Miura, Yoshinori Wakamatsu, Masami Onishi
    1975 Volume 39 Issue 9 Pages 903-908
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Iron-electrodeposited zinc diffusion couples were annealed at temperatures from 240 to 360°C at various compressive stresses. In the diffusion zone, intermetallic compounds appeared in the order of the ζ, δ1 and Γ phases. The thickness of the initial ζ phase layers which exist as a singl phase in the diffusion zone increases with increase in compressive stress up to 20 kg/cm2, remaining constant above this stress. The growth of the initial ζ phase layers at 50 kg/cm2 follows a parabolic rate law governing diffusion control. The temperature dependence of diffusion coefficients in the ζ phase layers was given by the following equation:
    (This article is not displayable. Please see full text pdf.)
    \ oindentThe equation is nearly equal to that estimated by our previous study which was carried out by the use of clamps.
    Kirkendall porosities develop at the interface between the ζ and zinc phases and restrict the transfer of atoms from zinc into the diffusion zone. The effect of compressive stress in the Fe-Zn system is to increase the growth rate of diffusion layers by decreasing the Kirkendall porosity.
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  • Yoshinori Shirane
    1975 Volume 39 Issue 9 Pages 908-916
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Equilibrium relations in the system NiO-MgO-SiO2 have been determined at 1400°C at oxygen pressure of air (pO2=0.21 atm). The following silicate and oxide phases have a stable equilibrium existence under these conditions, an orthosilicate solid solution with the olivine-type structure (approximate composition Mg2SiO4-Ni2SiO4), a metasilicate solid solution with the pyroxene-type structure (approximate composition MgSiO3-“NiSiO3”), and an oxide solid solution with the NaCl-type structure (approximate composition MgO-NiO). The pure nickel pyroxene is unstable relative to silica and the nickel olivine at oxygen pressure of air. Although pure NiSiO3 is unstable, cristobalite reacts with olivine to form a pyroxene in a low concentlation range of Ni2SiO4 in the olivine. The equilibrium among pyroxene, olivine and cristobalite at 1400°C is represented in the NiO-MgO-SiO2 plane at 1400°C by the three-phase triangle among olivine, pyroxene and cristobalite at oxygen pressure of air. The maximum solubility of NiSiO3 in the pyroxene solid solution at 1400°C is 12 mol%NiSiO3.
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  • Kazuo Tsumuraya, Seiichi Nishikawa
    1975 Volume 39 Issue 9 Pages 916-925
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The thermal stability of Sb-rich precipitates is investigated by means of the calorimetric method and electrical resistivity measurement in order to make clear the anomalous enhancement effect of a trace additional element As (0.01 wt%).
    Electrical resistivity is decreased with ageing time monotonously. With small arsenic additions, the precipitation of Pb-Sb alloys is greatly accelerated, and remarkable reversion phenomena are observed at the lower temperature side than that of the heat absorption due to the resolution of equilibrium precipitates in their specific heat vs temperature curves. In the case of Pb-Sb alloys free of arsenic, only a faint reversion reaction is observed, but a considerably longer time is necessary for the completion of reaction. It is shown that rather complicated reversion phenomena in Pb-Sb alloy system are fully interpreted by the critical size theory considering the change in size of precipitates, the degree of supersaturation and the relation between ageing and reversion temperature.
    The resolution mechanism of the precipitates is as follows: Since the coarsening process of the fine precipitates proceeds at the state of nonisotherm and nonequilibrium, the system dissolves the fine precipitates smaller than the critical size at the reversion temperature, so as to cancel the free energy increase of the system due to the interfacial energy between precipitates and matrix.
    The reversible precipitates are considered as fine equilibrium phase containing As atoms considering from its reversion behavior. Anomalous enhancement effect in Pb-Sb alloys with small arsenic addition may be attributed to the refinement and increase in distribution density of Sb-rich precipitates by As atoms or its clusters as “catalyzer” in the nucleation of the precipitates.
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  • Shigeo Zaima, Yuzo Takatsuji, Susumu Kamo
    1975 Volume 39 Issue 9 Pages 926-931
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    In the dry drilling of aluminium-silicon alloys, there were troubles on the accuracy of drilled holes, i.e. roundness of the hole figure and surface roughness of the drilled hole, and it was considered that these troubles were mainly due to the behaviour of built-up edge. So, in this paper, the behaviour of built-up edge was searched in regard to the helix angle of drill dimension by using a trial quick-stopping device for the drilling operations of commercial aluminium-silicon cast alloys, i.e., AC2A, AC3A, AC4A, AC4B and AC8A in JIS. The results obtained are as follows.
    Under the experimental drilling conditions, built-up edges were observed on the drill rake face and the formation of built-up edges was not so much near the drill margin part, but the formation was recognized largely approaching with the chisel part. On the whole, the formation of large built-up edges were found, but the formation of built-up edges for the Cu-bearing alloys such as AC 2A was not remarkable. And the formation for T6-material (heat treated) was smaller than the case of F-material (as cast). Then a good surface of the drilled hole will be obtained if the drilling condition for the formation of small built-up edges in the margin part is found in the case that the formation of built-up edges is recognized largely and, in the drilling of alloys of this system, the formation of small built-up edges near the margin part is expected when using the drill of a high helix angle near 40° and consequently a good surface of the drilled hole could be obtained.
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  • Mitsunori Tsutsui, Naomasa Fujise
    1975 Volume 39 Issue 9 Pages 932-938
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    In order to clarify the kinetics of hydrogen absorption in Zr during galvanostatic cathodic polarization in 4N H2SO4, 1N Na2SO4 and 1N NaOH, the hydrogen content was determined by solid state vacuum extraction at 900°C. In addition, the anodic polarization behavior of Zr hydride formed by the cathodic treatment was investigated by means of galvanostatic and potentiostatic methods.
    The results obtained are as follows:
    (1) The δ phase which had a fcc type structure (a=4.810±0.005 Å) and the ε phase which had a fct type structure (ac=0.930±0.002) were formed during the cathodic polarization.
    (2) The rate of hydrogen absorption increased abruptly at current density il, above which the rate was independent of c.d.
    il=5×10−2 A/cm2 (in Na2SO4),
    il=1×10−1 A/cm2 (in NaOH).
    The rate was initially linear but then became palabolic, indicating that the hydrogen diffusion was rate controlling. A value of 3×10−11 cm2/sec was obtained for the diffusion coefficient of hydrogen in Zr.
    (3) In the anodic polarization curve, the peak of current was created by oxidation of Zr hydride.
    The unitary formation rate R calculated from the gradient of the E-t curve was linearly related to logi, but R decreased with hydrogen content.
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  • Mineo Gonda, Tsuneo Takahashi, Hisafuji Watanabe
    1975 Volume 39 Issue 9 Pages 939-943
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The order-disorder transition temperature, the composition dependence of transition temperature and the ordering parameter in the β-brass containing 0.6∼5.9 at% manganese has been investigated by means of electrical resistivity and specific heat measurements. The results obtained are as follows.
    (1) The order-disorder transition temperature decreases linealy from 470°C to 432°C as the manganese content increased from 0.6 to 5.9 at%.
    (2) A small amount of disorderd lattice is quenched-in when quenched the β-brass containing 4.7∼5.9 at% manganese from 520°C.
    (3) The ordering parameter between Cu and Zn, Zn and Mn, Cu and Mn obtained are as follows:
    Ordering parameter between Cu and Zn=3.0 kcal/mol
    Ordering parameter between Zn and Mn=18.6 kcal/mol
    Ordering parameter between Cu and Mn=14.1 kcal/mol
    (4) The stability of the ordered lattice decreases by the addition of manganese.
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  • Kuniyasu Sakai, Masanori Kiyoshige, Kiyoshi Kita
    1975 Volume 39 Issue 9 Pages 944-951
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The susceptibility to delayed fracture of 18%Ni Maraging and SNCM 8 steels which were heat-treated variously, was studied in 3%NaCl solution by means of the following three methods; constant load, constant displacement and constant strain rate methods. Delayed fracture surfaces of these steels were observed by scanning electron microscopy.
    The following results were obtained:
    (1) Heat treatment and loading condition have an effect on the crack propagation rate of delayed fracture of the steels, but have only a little effect on the morphology of the fracture surface. There is a wide range of the stress intensity factor over which the crack propagation rate is essentially constant.
    (2) The value of lower critical stress obtained from the constant load method is not directly related to the value of threshold stress intensity factor obtained from the constant displacement method.
    (3) In the strain rate range of 2×10−6 to 8×10−4 sec−1 at the constant strain rate method, the fracture behavior of SNCM 8 steel tempered at 300°C depends on the strain rate, and the smaller the strain rate the lower the reduction of area of this steel.
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  • Masanori Iwase, Kimio Fujimura, Toshisada Mori
    1975 Volume 39 Issue 9 Pages 952-959
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The emf measurement of two types of solid oxide galvanic cells have been carried out to measure the oxygen partial pressure in argon and nitrogen. The cells are
    Cell (A) Pt, pO2(gas)/ZrO2(CaO)/pO2′′(gas), Pt
    Cell (B) Pt, Ni-NiO/ZrO2(CaO)/O(in Ag), pO2′′(gas), Fe.
    \ oindentCell (A) was used to measure the oxygen partial pressure directly. Cell (B) was used for indirect measurement by determinig the oxygen activity in liquid silver in equilibrium with oxygen in argon blown into the melt.
    The obtained results are as follows:
    (1) In the case of cell (A), the emf was increased with increasing flow rate of argon, but constant emf values were obtained by keeping the flow rate beyond a critical value i, e, “Vmin”.
    (2) When the flow rate was beyond the Vmin for cell (A), the measured values of oxygen partial pressure showed a good accordance with that by cell (A).
    (3) Ullmann’s equation gave an explanation to the relation between the gas permeability of solid electrolyte and the dependence of emf on the gas flow rate in cell (A).
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  • Masakazu Sakaguchi, Takakuni Hirabayashi, Kazuhisa Nakazato
    1975 Volume 39 Issue 9 Pages 960-963
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The carburizing reaction of steel with the gases produced by the pyrolysis of Prussian blue was carried out in each atmosphere of O2, NH3 and H2S, and the behavior of the atmospheres was investigated.
    In O2 atmosphere, the amount of carburization showed obviously a maximum at about 3 cmHg of O2 pressure, and it was approximately proportional to pCO2pCO2. In NH3 atmosphere, the amount of carburization increased gradually with NH3 pressure until 10 cmHg, and it was kept constant above that pressure. In H2S atmosphere, the carburization was accelerated by the existence of H2S, but the sulfurization was suppressed by the carburization and most of the sulfur was segregated in the grainboundary of steel.
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  • Ry\={u}ta Onodera, Seiz\={o} Teshima
    1975 Volume 39 Issue 9 Pages 964-970
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    It is well known that ductile fracture occurs by the void coalescence, but few experimental studies of void growth have been published to date. In this paper, we describe an experimental study of the increasing rate of volume fraction of voids with deformation in low carbon steel. Many drawn or annealed round specimens whose initial shapes were smooth or notched were deformed in tension at room temperature. Some of the specimens, interrupted tensile deformation, were either ground by a small grinder to increase the radius of curvature of the neck or annealed at 700°C to remove strain hardening, and deformed again. Densities of the necked region of these specimens were measured. The results lead to the following conclusions: (1) Except in the early stage of deformation in which it is expected for microcracks to grow into voids, the increasing rate of volume fraction of voids (v) with true strain (ε) can be expressed by \dfracd(lnv)dε=1. This equation can be understood that each void is elongated equal to matrix in tensile direction with no reduction of its cross-sectional area. Otherwise in the early stage of deformation, v increased more rapidly than expected from the above equation. These experimental results can be explained well by the model proposed by Gurland et al. (2) In the early stage of deformation, v of the notched specimen increased more rapidly than that of the smooth one, but except in this stage v of the former increased as expected from the above equation, too. It is reasonable to consider from these results that the radial stress has a greater effect on void formation than on void growth. (3) After the true strain measured from annealing state exceeded 0.5∼0.7, the increasing rate of v was accelerated. Therefore we conclude that strain hardening has direct effects on void growth.
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  • Ry\={u}ta Onodera, Seiz\={o} Teshima
    1975 Volume 39 Issue 9 Pages 970-976
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    It has been recognized theoretically and experimentally that the ductility of metals in tension is influenced by the volume fraction of voids and radial stress. But almost no attempts have been reported to clarify what conditions must be satisfied to induce ductile fracture. In this paper we consider three quantities, namely volume fraction of voids, radial stress and strain hardening as the factors influencing ductile fracture, and try to obtain the relation among these factors at the moment when ductile fracture occurs. Radial stress and strain hardening are each expressed in terms of the curvature of neck of specimen and strain after annealing.
    Many drawn or annealed specimens of low carbon steel which were initially smooth or notched round bar were deformed and fractured in tension at room temperature. Some of specimens, interrupted deformation at various strains, were either ground by a small grinder to increase the radius of curvature of neck (R) or annealed at 700°C for 4 min in the air to remove strain hardening, and deformed again. These operations were repeated several times in some of the specimens. Fracture strains and rR (r=radius of narrowest section of specimen) at various strains were measured on all specimens. The results obtained are as follows. (1) Radial stress and strain hardening give not only indirect effects upon ductile fracture through an increase of volume fraction of voids but also direct effects on the fracture condition. (2) The condition of fracture can be shown as a curved surface in three-dimensional space whose axes represent the volume fraction of voids, rR, and strain after final annealing. The volume fractions of voids in various specimens were estimated from the experimental results reported previously.
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  • Shigeru Mukai, Junji Shibata, Sanji Nishimura
    1975 Volume 39 Issue 9 Pages 976-981
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    The effect of temperature on the solvent extraction of Cu, Ni, Co and Mn with Versatic acid 911 diluted in benzene was studied. Extraction temperature was varied between 10 and 60°C, and the results obtained are summarized as follows:
    (1) The equilibrium distribution ratio of metal is raised with the temperature. (2) The change in the composition of extracted species was not observed in the extraction of Cu and Ni in this temperature range, while the extracted species of Co was of dimeric form above 40°C and Mn ion was oxidized in the aqueous phase above the same temperature. (3) The extraction reaction of these metals is endothermic, and the heat of extraction of Cu, Ni and Co were 10.8, 14.5 and 18.9 kcal/mol, respectively. (4) A linear relationship in the form of pH0.5=a+bT−1 (a, b: constant) was observed in the extraction of these metals.
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  • Yoichi Ishida, Toshiyuki Yamamoto
    1975 Volume 39 Issue 9 Pages 982-990
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    Grain boundary energy cusp is a tasic property of theoretical importance. The practical significance depends largely on how strongly the population of the boundary is influenced by the energy cusp. The present work is a statistical analysis of the population in vapor-grown iron bicrystals. During the growth, the disturbing effects of the surroundings appeared relatively weak.
    The question investigated first is whether all the bicrystal boundary is in perfect coincidence relationship or only distribute about them with maxima at the coincidence orientations. Electron channeling pattern with an error limit better than 0.1° was applied to resolve the problem. It was concluded that they only distribute about the coincidence orientation.
    The observed distribution was very heterogeneous; The major component of the misorientation from the perfect coincidence was of tilt type. The result is explained if the population of the grain boundary is controlled by the energy and the boundary within the enrgy cusp is composed of grain boundary dislocation network superimposed upon the coincidence related boundary.
    Near coincidence boundaries were also observed although the population was very small. The boundaries were composed of two densely packed lattice planes joined parallel along the boundary. A general trend in the histogram suggested that the bicrystal is formed by the nucleation of a sister crystal on the {100} stepped surface of a growing single crystal.
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  • Iwao Katayama, Jun Shibata, Zensaku Kozuka
    1975 Volume 39 Issue 9 Pages 990-995
    Published: 1975
    Released: April 04, 2008
    JOURNALS FREE ACCESS
    E.M.F. of galvanic cells with the solid electrolyte (ZrO2+CaO) was measured to determine the standard molar free energies of formation of Sb2O3, GeO2 (hexagonal), GeO2 (tetragonal) and In2O3. The cells used were as follows:
    (This article is not displayable. Please see full text pdf.)
    \ oindentThe results were represented by the following equations:
    (This article is not displayable. Please see full text pdf.)
    \ oindentand they were compared with previously reported values. In the In-O system, e.m.f. corresponding to the formation of solid In2O were not obtained by the titration method.
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