巻号一覧
43 巻, 7 号
選択された号の論文の18件中1～18を表示しています
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江島 辰彦, 嶋影 和宣, 横尾 俊信, 中島 和隆, 武井 和彦1979 年 43 巻 7 号 p. 577-583
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーViscosity coefficients of molten ZnCl2-MCl (M=Cd, Pb, Sn, Ba) binary systems have been measured by means of the rotating cylinder method on the ZnCl2-rich side. The results obtained are summarized as follows:
(1) Viscosity coefficient for each salt mixture decreases drastically with increasing MCl2 content and temperature. The temperature dependence of viscosity coefficients exhibits non-Arrhenius behavior in the composition range of 0-about 30 mol%MCl2 (0-about 10 mol%BaCl2 for the ZnCl2-BaCl2 system).
(2) Apparent activation energies for viscous flow in these binary systems decrease markedly with increasing MCl2 content in the order of CdCl2<SnCl2<PbCl2<BaCl2 in the composition range up to about 25 mol%MCl2.
(3) Isothermal viscosity coefficients and activation energies of the molten ZnCl2-SnCl2 system are larger than those of the molten ZnCl2-PbCl2 system in the composition range less than 25 mol%MCl2, but their magnitudes reverse in the composition range of more than 25 mol%MCl2.
(4) The effect of each metallic cation on the destruction of molten ZnCl2 polymer is explained on the basis of simple Førland’s model.抄録全体を表示PDF形式でダウンロード (569K) -
中川 正樹, 有賀 正, 矢島 悦次郎1979 年 43 巻 7 号 p. 583-589
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe Effect of cold work on the aging behavior of modulated structure were investigated for Cu-Ti alloys which show a typical modulated structure, by means of electrical resistivity, transmission electron microscopy, and hardness and 0.1% proof stress measurements. We prepared Cu-5 at%Ti supersaturated alloys by rapid cooling, and these alloys were rolled and aged at 623,673 and 723 K.
The results obtained were as follow:
(1) In the short time aging specimens the resistivity of the as-quenched alloy indicated three principal processes on the semilogarithmic plot. In the case of the deformed alloy, however, it was found that the first process disappeared, but the second and third processes continued to exist. The second process is thought to correspond to the predominent constant wavelength range defined in Cahn’s spinodal decomposition theory. The average predominent wavelength was about 4.8 nm upon aging at 673 K. The experimental activation energy for this process was 202.1 kJ/mol for the as-quenched alloys and 99.2 kJ/mol for the deformed alloys and the effect of cold work was initially affected in the aging process.
(2) For a long time aging, the electrical resistivity of the as-quenched and deformed alloys decreased during aging and then became constant. These break points of the resistivity curves corresponded to aging time at the maximum hardness. These break point of the deformed alloys occurred earlier than the as-quench alloys. Eventually, the aging behavior was accelerated by cold work.
(3) The deformed alloys were higher in both maximum hardness and 0.1% proof stress than as-quench alloys. The amount of hardness increased with increasing deformation.抄録全体を表示PDF形式でダウンロード (901K) -
小原 嗣朗, 武藤 範雄, 今西 良文1979 年 43 巻 7 号 p. 589-594
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe TiC coating on carbon fiber by chemical vapour deposition and the compatibility of TiC coated carbon fiber with aluminum have been investigated. The elastic modulus of TiC coated carbon fiber increased with the thickness of the TiC layer. The tensile fracture strength also increased with the thickness of the TiC layer, compared with that of carbon fiber heated at the same temperature as the coating treatment.
The compatibility of carbon fiber with aluminum was studied by strength testing after heating the aluminum coated fiber specimens in an argon atmosphere. Though the uncoated carbon fiber showed a marked loss in strength after the heat treatment in contact with the aluminum layer, the TiC coated carbon fiber showed no loss in strength after the heat treatments at 673 to 873 K for 25 h and also showed no noticeable loss in strength after the heat treatments at 973 to 1273 K for 30 min. However, a slight degradation in strength was observed after the heat treatment at 1373 K for 30 min.抄録全体を表示PDF形式でダウンロード (521K) -
小若 正倫, 工藤 赳夫1979 年 43 巻 7 号 p. 595-601
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーIntergranular attack behaviour of sensitized 304 stainless steel, e.g., the effects of potential and stress on intergranular attack, was studied in both polythionic acid and 15%H2SO4 solutions, and the difference between intergranular stress corrosion cracking (IGSCC) and intergranular corrosion behaviours was discussed. The results obtained are as follows:
(1) Susceptibility to IGSCC in the polythionic acid solution was greatest in the potential range of −0.1 to 0 V (vs SCE), and intergranular corrosion occurred between −0.4 and −0.1 V. No intergranular corrosion was observed at the corrosion potential.
(2) The formation of a sulfide film plays an important role in the mechanism of IGSCC in the polythionic acid solution, and it is considered that the destruction of the film by stress is essential to the occurrence of intergranular attack at the corrosion potential.
(3) In 15%H2SO4 solution at 373 K, intergranular corrosion occurred in the potential range of −0.2 to +0.1 V. Stress is not necessary for the intergranular attack, although it accelerates intergranular corrosion.
(4) The mechanism was proposed on the intergranular attack of sensitized stainless steel in the polythionic acid solution.抄録全体を表示PDF形式でダウンロード (1013K) -
藤田 欽一郎, 黄 燕清, 多田 政義1979 年 43 巻 7 号 p. 601-610
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe present paper dealt with the studies on the equilibria of Ta-H, Nb-H, and V-H systems, in terms of the P(hydrogen pressure)-T(temperature)-X(composition of hydrogen in metal) relationships by using a modified Sieverts’ apparatus in the range of 0.1∼104 Pa, 353∼773 K and 0.1∼40 at% hydrogen, and the phase boundary of each diagram has been proposed on the basis of the results of electrical resistance measurement.
Vacuum degassing of the sample was done by heating it up to 1573∼2173 K at high frequency under a vacuum of less than 2×10−4 Pa until the leak rate reached 6×10−7 (l·Pa/s) at least.
The equilibrium pressure of hydrogen in each system was lower than the previously reported value. The plateau pressure which indicated the coexistence of the two was measured to 6.0×10−1 Pa at 423 K in the range 14∼30 at%H for the Nb-H system, and the eutectoid temperature of this system was found at 373 K by the electrical resistance measuerment. Relative partial molar quantities of hydrogen in the three metals were slightly larger than the reported values of former works.抄録全体を表示PDF形式でダウンロード (700K) -
藤田 欽一郎, 黄 燕清, 多田 政義1979 年 43 巻 7 号 p. 611-617
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe purpose of this work dealt with the measurements of the equilibrium pressure of deuterium and with the determination of the thermodynamic properties of deuterium in V, Nb and Ta. The P-T-X relationships were established for these three systems using the modified Sieverts’ apparatus in the range of 0.1∼104 Pa, 0.1∼40 atomic percent of deuterium and the temperature range of 423∼773 K.
The equilibrium pressure of deuterium and the relative partial molar quantities of deuterium are larger than that of hydrogen in the three systems. In the Nb-D system, the two phase region has been measured in the range of 19∼32 at%D, 2.3×10−1 Pa at an isotherm of 443 K. The isocomposition measurement was carried out in the two system, V-D, and Nb-D, and the two phase region for each system was estimated at temperatures below 393 K for V-D and 453 K for Nb-D, respectively. The partial phase diagram of each system was proposed on the basis of the results of the resistometric work. It is clear that the phase boundary of α⁄(α+β) in each of the Nb-D and Ta-D systems was located at a slightly higher temperature position than that of the Nb-H and Ta-H systems. However, in the system of V-D this was a reverse.抄録全体を表示PDF形式でダウンロード (452K) -
田中 浩, 吉田 一也1979 年 43 巻 7 号 p. 618-625
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe influence of oxygen contents in copper wire on the occurrence of cupping has been studied. The defect occurred more often with increasing oxygen content, especially, when it was >400 ppm and no cupping was observed when it was as low as 4 ppm. From microscopic observations, it has been concluded that the amount of Cu2O which causes the wire to break easily induces void formation under tensile force and acts as the cause to accelerate the defect. The stress distributions in the deforming zones found both by FEM and slip line solution were also shown as they are the controlling factors for cupping.抄録全体を表示PDF形式でダウンロード (1441K) -
大内 義昭, 加藤 栄一1979 年 43 巻 7 号 p. 625-633
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe viscosities of melts in the PbO-CaO-SiO2, PbO-MgO-SiO2, PbO-BaO-SiO2, PbO-NiO-SiO2 and PbO-CoO-SiO2 systems containing 50 mol% SiO2 have been measured in the temperature range from 950 to 1250°C by means of the counterbalanced sphere method. Instead of Stokes’s law, Oseen’s equation has been applied to determine viscosities in the range from 0.1 to 1 Pa·s under the experimental condition that the Reynolds number of the flow is higher than 0.1. From the slope of the linear relation between log viscosity and 1⁄T, the activation energy for viscous flow is evaluated.
The structural changes of the silicates anions in these melts are estimated from the viscosity changes with composition, and these results are combined with the previously reported experimental results on the activities of PbO in these systems to discuss the behaviors of the basic oxides in these systems.
The results obtained from the systems containing the transition metal oxide, PbO-NiO-SiO2 and PbO-CoO-SiO2, indicate that when the content of NiO or CoO in the ternary lead-metasilicates is less than 4 mol%, NiO or CoO in these melts behaves as if it were more basic than it is in the binary silicate melt.
The results obtained from the systems containing the alkaline earth metal oxide, PbO-CaO-SiO2, PbO-MgO-SiO2 or PbO-BaO-SiO2, indicate that when the content of CaO, MgO or BaO in the ternary lead-metasilicate is less than 10 mol%, CaO, MgO or BaO in these melts behaves as if it were more acidic than it is in the binary silicate melt.
The changes in basicity of basic oxides in the other ternary melts are also discussed.抄録全体を表示PDF形式でダウンロード (716K) -
白川 究, 増本 健1979 年 43 巻 7 号 p. 634-636
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe strain gauge factor K at room temperature, the electrical resistivity ρ at 20°C and its mean temperature coefficient Cf, and the mean thermal electromotive force Emf in the temperature range of 0° to 40°C have been measured with ribbons of amorphous Cu-Ag-P alloys. Compared with conventional strain gauge materials, these amorphous alloys exhibit comparable K(1.8∼3.1), high ρ (135.6∼154.3×10−8 Ω·m), negative Cf(−0.67∼−1.23×10−4/°C) and low Emf(1.02∼1.07 μV/°C). From the above results, these amorphous alloys are expected to serve as strain guage alloys below the crystallization temperatures.抄録全体を表示PDF形式でダウンロード (381K) -
白川 究, 井門 秀秋1979 年 43 巻 7 号 p. 636-639
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe ferrimagnetic to antiferromagnetic transition of the compounds Mn2Sb-Bi is investigated by following the change of lattice parameters, thermomagnetic properties and thermal expansion of the compounds. The single Cu2Sb-type phase region in the Mn2Sb(1−x)Bix system exists from x=0 to x=0.175. Although the C-axes of the Mn2Sb-Bi system at room temperature are longer than that of ferrimagnetic compound Mn2Sb, the Mn2Sb-Bi system transforms from the ferrimagnetic to the antiferromagnetic state with decreasing temperature. This result could be explained in terms of a larger thermal expansion coefficient of the c-axis in the Mn2Sb-Bi system than that in Mn2Sb. The transition temperature of the Mn2Sb-Bi system increases initially and then decreases monotonously in the composition range of Bi above x=0.05 with increase in Bi concentration.抄録全体を表示PDF形式でダウンロード (315K) -
藤平 昭男1979 年 43 巻 7 号 p. 640-646
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーFor the purpose of realizing rapid graphitization in a low alloy structural steel (0.24 wt%C, 1.42 wt%Si and 2.13 wt%Ni), the effects of pre-quenching, pre-cold rolling and graphitization temperatures on the graphitization rate were studied by means of dilatometric measurements and optical microscopic observations. The main results obtained were as follows. (1) The time required for 50% graphitization, τ50, showed charactaristic C curve behavior with changing graphitization temperature, and the noses of the C curves, i.e. the temperatures of the highest graphitizing rate, were in the range of 923∼973 K. (2) The effects of pre-quenching were remarkable and rather complex, where the smallest τ50 of about 1 h (the highest rate), was obtained when pre-quenched from the temperature just above Ac1 and graphitized at 973 K. (3) The effect of pre-cold rolling was simpler and weaker than that of pre-quenching and τ50 decreases monotonically with increasing reduction of thickness. (4) The number of graphite nodules in the specimens also changes remarkably with pre-treatments and graphitizing temperatures, and the most dense and the finest graphite nodules (average diameter of ca. 0.3 μm) were obtained when pre-quenched from the temperature just above Ac1 and graphitized at 777 K.抄録全体を表示PDF形式でダウンロード (1595K) -
花井 義泰, 須藤 一1979 年 43 巻 7 号 p. 647-652
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe Gleeble tensile test, Auger electron spectroscopy and electron microscopy techniques were used to investigate the relationship between the over-heating embrittlement (the loss in ductility on cooling below 1300°C) and the behavior of sulphur at grain boundaries in 0.55%C-1%Ni-3%Cr steel.
The Fe-side sectional diagram of this steel bearing sulphur was obtained by means of a metallographic examination, and it shows that sulphide particles are melted as droplets at about 1100°C and dissolved in γ-Fe at about 1300°C. The number and size of sulphide particles at grain boundaries were measured, and it was found that the short time interruption of cooling at about 1100°C during cooling from 1300 to 900°C introduced the fine dispersion of grain boundary sulphide. The fine dispersion of grain boundary sulphide is certainly one of the most important factors affecting the over-heating embrittlement, and also supersaturated sulphur or its grain boundary adsorption may be concerned.抄録全体を表示PDF形式でダウンロード (885K) -
松山 豊和, 須藤 一1979 年 43 巻 7 号 p. 652-658
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe phenomenon of temper brittleness has been shown to be due to the segregation of impurities (P, Sb, etc.) to grain boundaries. It has been also shown that the presence of both impurities and alloying elements (Ni, Mn, Cr, etc.) is the prerequisite for temper brittleness. Some investigators have attached importance to the role of carbon or carbide. For a fundamental study on temper brittleness, the segregation of P, alloying elements (Ni, Mn, Cr, Mo, W) and other impurities (C, N, O, S) to grain boundaries in α-iron solid solution containing 1 at%P and the above-mentioned alloying elements quenched from the temperature of 1200°C to 700°C has been measured by means of AES. The results obtained are as follows:
(1) The saturation value of segregation of P was not affected by addition of alloying elements. From this result, it is improbable that a new two-dimensional boundary phosphide phase is formed by alloying Ni, Mn, Cr, Mo or W, and that these alloying elements are in severe competition with P for the segregation sites at the boundaries.
(2) Cr is hardly segregated to boundarise because of the little difference in atomic size between Fe and Cr. But Cr is more and more segregated cooperatively with N with decreasing temperature.
(3) Both C and N atoms segregate to the boundaries. By alloying Mo, the segregation of N is suppressed and the segregation of C is promoted. There is a competition between C and N for the segregation sites at the boundaries, but the alloying elements do not compete with C and N for the segregation sites.
(4) P and S segregate competitively to each other to boundaries.抄録全体を表示PDF形式でダウンロード (551K) -
矢野 信三, 諸住 正太郎, 幸田 成康1979 年 43 巻 7 号 p. 658-664
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーMolybdenum alloys containing up to 5.48 wt%Ti were studied after nitriding in a purified nitrogen (0.1 MPa) at 1573∼1773 K. The obtained results disagreed with those reported by some worker, because the latter appeared to be affected by a small amount of oxygen in nitrogen.
Hardness of nitrided layer increased, with increasing titanium content and decreasing treatment temperature, to the maximum value of 800 VPN. Electron microscopy and electron and X-ray diffraction revealed three kinds of nitrides; namely, ribbon-shaped equilibrium TiN, disk-shaped metastable TiN which appeared to replace the G.P.zone, and non-equilibrium nitride with an unknown structure. At temperatures below 1673 K, preferential precipitation beneath nitriding front was observed on dislocations created to release the lattice expansion due to nitriding. This region affected layer thicknesses and hardness profiles. At 1773 K, the nitriding kinetics obeyed the parabolic law predicted by Wagner’s theory, but below 1673 K it was not the case. The latter departure was explained by the preferential precipitation region formed in front of the layer and non-equilibrium nitride precipitation.抄録全体を表示PDF形式でダウンロード (880K) -
佐藤 昭規, 昆 謙造, 辻川 茂男, 久松 敬弘1979 年 43 巻 7 号 p. 664-671
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe initiation curve of carbide precipitation at grain boundaries was determined by electronmicroscope observation of the specimens aged for various times at 350∼980°C. Carbides are easily recognized in 10 min above 700°C, but not recognized even after 9×103 h at 350°C. Under the condition near the initiation curve a specimen can have boundaries with or without precipitates. This fact shows that the precipitation depends on a crystallographic characteristic of grain boundaries. The rate of intergranular corrosion under the potentiostatically controlled condition in 1N-H2SO4 solution decreases with aging time and becomes constant after minimum, while the rate attacked under the naturally immersed condition in boiling 10N-HNO3 solution increases with aging time and becomes constant after passing through a maximum. In both water-quenched and aged specimens, the depth of intergranular corrosion decreases at coincidence boundaries and twin boundaries with [100], [110] and [111] rotation axes.抄録全体を表示PDF形式でダウンロード (1235K) -
和泉 康男, 岡野 洋一郎, 藤本 英明, 長村 光造, 山川 宏二, 村上 陽太郎1979 年 43 巻 7 号 p. 671-679
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーBoth the metallurgical and electrochemical studies were simultaneously performed in order to understand the mechanism of stress corrosion cracking (SC cracking) in Al-Zn-Mg alloys. The intergranular corrosion occurred preferentially in the low temperature aged specimens. Its ageing condition resulted in the high SC susceptibility and the pH dependence of the corrosive solution, where the SC cracking life was suggested to be controlled by the nucleation process of the SC crack at the grain boundary. On the other hand, general corrosion progressed in the two-step aged specimens. The alloy containing a small amount of the Cu element had a tendency toward general corrosion regardless of the heat treatment. The general corrosion was very effective in decreasing the SC susceptibility and the pH dependence. For the long life of SC cracking, the propagation of SC cracking exerted a dominant role. The propagation was modulated by some profitable microstructural factors as the region denuded of grain boundary precipitates and the precipitated free zones.抄録全体を表示PDF形式でダウンロード (945K) -
香山 滉一郎, 橋本 雍彦, 桐原 朝夫1979 年 43 巻 7 号 p. 679-685
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーThe cathodic deposition of vanadium was investigated using the V-C-O alloys (crude vanadium, V2C and VC) produced by carbothermic reduction as the anode materials, and two kinds of molten salts, KCl(44)-NaCl(44)-NaF(7)-K2NaVF6 (5 mol%) and KF(62)-NaF(33)-K2NaVF6 (5 mol%), as the electrolytes. The cathode current efficiency depended strongly on the anode current density and little on the cathode current density. Initial anode current densities more than 200 A/m2 was necessary to obtain high cathode current efficiencies. It was found that crude vanadium (C: 0.45∼1.27, O: 0.66∼3.66 wt%) is more suitable for the anode material than V2C and VC, and the KCl-NaCl-NaF-K2NaVF6 molten salt is more appropriate for the electrolyte than the KF-NaF-K2NaVF6 molten salt. Without special purification of the bath, pure vanadium which contained oxygen ranging from 1600 to 3000 ppm and carbon ranging from 90 to 270 ppm was easily obtained from the crude vanadium (C: 0.45∼1.27, O: 0.66∼3.66 wt%) in the KCl-NaCl-NaF-K2NaVF6 bath under the electrolytic conditions of the initial anode current densities of 210 to 290 A/m2, the initial cathode current density of 10000 A/m2, and the bath temperature of 725°C. The microvickers hardness number of vanadium obtained ranged from 159 to 220 (1 kg-load). Eighty-five percent of vanadium in the crude vanadium was recovered at the cathode.抄録全体を表示PDF形式でダウンロード (871K) -
木村 宏, 松井 秀樹, 森谷 信義, 木村 晃彦1979 年 43 巻 7 号 p. 686-687
発行日: 1979年
公開日: 2008/04/04
ジャーナル フリーPDF形式でダウンロード (180K)
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