巻号一覧
47 巻, 1 号
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遠藤 孝雄, 福富 洋志, 丸茂 敬和, 吉田 賢次1983 年 47 巻 1 号 p. 1-9
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーRecovery and work hardening of Al have been investigated at temperatures from 623 to 848 K and strain rates from 2×10−4 to 7×10−3 s−1. Rates of recovery r (≡−∂σ⁄σt) and work hardening h (≡∂σ⁄∂ε) were obtained from stress relaxation analysis at steady states. The transition temperature Tc from pipe to bulk diffusion controlled regime was found to be about 735 K. Steady state creep rate \dotεs, r and h were represented by \dotεs=A(σ⁄E)nexp(−Qc⁄RT), r=B(σ⁄E)nrexp(−Qr⁄RT) and h=C(σ⁄E)nhexp(−Qh⁄RT), where A, B and C were constants, E the Young’s modulus, σ the applied stress, R the universal gas constant and T the temperature. n, nr, nh, Qc, Qr and Qh were 4.0(4.6), 2.7(2.3), −1.5(−2.4), 140(110) kJ·mol−1, 84(38) kJ·mol−1 and −65(−73) kJ·mol−1, respectively, where the values in the parenthises were those below Tc.
Based on a network growth model and an empirical dislocation density-strain relationship, r and h were roughly estimated. The model gives the correct order of magnitude ot them. Using \dotεs=r⁄h, \dotεs is represented by \dotεs=4.5×104(DGb⁄kT)(σ⁄G)4, where D is the coefficient of self-diffusion, G the shear modulus, b the Burgers vector and k the Boltzmann constant. The equation predicts the measured steady state creep rates above Tc within a factor of 3. The difference between Qc and Qr was briefly discussed.抄録全体を表示PDF形式でダウンロード (1318K) -
小野寺 龍太, 清水 峯男, 古賀 守1983 年 47 巻 1 号 p. 10-16
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーThe rate sensitivity of flow stress was investigated as a function of pre-strain for solution-treated and furnace-cooled aluminium alloy (2017), over a temperature range encompassing the regime of jerky flow (Portevin-Le Chatelier effect). In strain rate change (increase) tests, the stress increased at first and then decreased gradually to the stress level determined by the strain and the strain rate. This fact suggests that the stress relies on the strain rate in two manners; One is the “frictional stress”, which is assumed to be uniquely determined by the strain rate, and the other is the “interaction stress” between dislocations and solute atoms or precipitates, which is assumed to approach with time the limiting value determined by the strain rate when this is changed. The relation between stress and log (strain rate) was linear in each case but its slope was positive for the former and negative for the latter. For solution treated specimens the slope of frictional and total stress was about 3 MPa and −2 MPa, respectively, at room temperature. The absolute values of these were unaffected by the strain rate up to ∼10−2 s−1, but increased slightly with strain.
A temperature range in which the total rate sensitivity was negative was about from 200 K to 400 K for solution treated specimens and from 230 K to 500 K for furnace-cooled specmiens. These ranges were wider than that in which P-L effect was observed; only at room temperature for the former, and between 228 and 398 K for the latter at the strain rate equal to 10−4 s−1. Therefore, it is impossible to explain the P-L effect only by the condition that the rate sensitivity is negative.抄録全体を表示PDF形式でダウンロード (918K) -
上田 康, 土居 定雄, 近藤 明1983 年 47 巻 1 号 p. 17-20
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーThe electrical conductivity of a slag consisting of a mixture with CaO-SiO2-CaF2 was measured by the four electrodes method, using several Pt crucibles of different volumes. In the case of a small crucible, the conductivity was observed to be frequency dependent; it increased with increasing frequency. In the case of a large crucible, the conductivity was almost independent of frequency in the range from 0.2 kHz to 10 kHz. The shift of phase angles existed between the current and the potential in the slag. It was shown that the slag acted not only as a resistance but also as a reactance. In the case of a small crucible, it seemed that the impedance of the slag was affected by the crucible wall and, hence, that the frequency dependence of the conductivity resulted.抄録全体を表示PDF形式でダウンロード (496K) -
中村 博昭, 郡司 好喜1983 年 47 巻 1 号 p. 21-25
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーThe electrical conductivities of MgS and SrS disks carefully prepared to avoid any contamination have been measured at temperatures from 973 to 1223 K and in the PS2 range from 10−10 to 104 Pa. Because the conductivities were independent of sulfur pressure in the low sulfur pressure range, it was concluded that MgS and SrS may be ionic conductors. The specific conductivities can be expressed as follow;
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\ oindentand the apparent activation energies for the conduction of MgS and SrS are 218 kJ/mol and 180 kJ/mol, respectively.
However, in the high sulfur pressure range, the specific conductivities of both sulfides increase with an increase in sulfur pressure, suggesting the positive hole conduction.抄録全体を表示PDF形式でダウンロード (548K) -
俣野 泰司, 角田 成夫, 森永 健次, 柳ヶ瀬 勉1983 年 47 巻 1 号 p. 25-30
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーThe electrical conductivity (κ) and the viscosity (η) of molten ferrite systems have been measured to find out the behavior of Fe3+-ion in these melts. Fe3+-ion in these melts is concluded to be amphoteric, that is, Fe3+-ion is located in both the tetrahedrally (Fe3+(4)) and the octahedrally (Fe3+(6)) coordinated state. It means that the Fe3+(4) forms an oxygen complex anion like SiO2, and the Fe3+(6) is a cation like CaO. The Fe3+(4)/Fe3+(6) ratio depends mainly upon the content and basicity of the added basic oxide and was estimated for the RO-Fe2O3 system (R=Ca, Sr, Ba). The dependence of κ and η upon the composition of melts has been discussed in terms of the ratio Fe3+(4)/Fe3+(6). The Stokes equation of κ may be applied for the κ and η of these melts, but the observed value of κ is 5-20 times as large as the value calculated from the Stokes equation.抄録全体を表示PDF形式でダウンロード (775K) -
原 信義, 杉本 克久1983 年 47 巻 1 号 p. 31-39
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーIn order to get spectral information on the in situ analysis of passive films on Ni, modulated reflection spectra from thin films of several Ni oxides and oxyhydroxides have been measured. Thin films of NiO, α- and β-Ni(OH)2, γ-NiOOH·NiO2, β-NiOOH, and γ-NiOOH·2NiO2 were coated on Pt electrodes using various deposition techniques, and then their spectra were measured in 1 kmol·m−3 Na2SO4 (pH 8.0 and 12.0) and 1 kmol·m−3 NaOH (pH 13.7). Effects of composition and thickness of films on the spectra were examined.
It was found that the spectrum of each film had a characteristic structure; the spectrum for a NiO film formed by CVD technique showed a peak at 3.0 eV and a trough at 4.2 eV, that for a NiOx (x<1.5) film formed by an anodic oxidation of NiO only one broad peak at 3.4 eV, that for a γ-NiOOH·NiO2 film formed by the anodic oxidation of α-Ni(OH)2 a large sharp peak at 2.0 eV and two small peaks at 3.5 and 4.6 eV, that for a β-NiOOH film formed by the anodic oxidation of β-Ni(OH)2 a large broad peak at 2.1 eV and two small peaks at 3.6 and 4.5 eV, and that for a γ-NiOOH·2NiO2 film formed by anodic deposition also three peaks at 2.0, 2.5, and 3.4 eV. The spectra for α- and β-Ni(OH)2, however, showed no characteristic structures.
Change in the thickness of the films has only an effect on the relative intensity of peaks in the spectra, except for a case in the spectrum for a NiO film at lower potentials.抄録全体を表示PDF形式でダウンロード (1257K) -
原 信義, 杉本 克久1983 年 47 巻 1 号 p. 39-47
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーModulated reflection spectra have been measured on Ni at passive and transpassive potentials in 0.5 kmol·m−3 H2SO4 (pH 0.3), 1 kmol·m−3 Na2SO4 (pH 2.0-12.0), 0.1 kmol·m−3 NaOH (pH 13.1), and 1 kmol·m−3 NaOH (pH 13.7). By comparing the spectra with those of several reference Ni oxides and oxyhydroxides, kinds of consitituent substances of passive and transpassive films formed on Ni in these solutions have been identified.
It was found that the composition of the films changed remarkably with solution pH and electrode potential: In acid solutions of pH≤4.0, the primary passivation film was mainly composed of NiO, and the transpassivation film of a nonstoichiometric Ni(II) oxide, i.e., NiOx. The value of x in NiOx increased with increasing potential. The change in the film composition in neutral solutions of pH between 6.0 and 9.0 was very similar to that in acid solutions, except that a thin layer of γ-NiOOH·2NiO2 was formed on the surface of NiOx film at transpassivation and oxygen evolution potentials through the anodic oxidation of dissolved Ni2+ ions. In alkaline solutions of pH≥10.0, the passivation films formed at lower potentials were composed of Ni(OH)2 and NiO layers. The Ni(OH)2 layer, which was the outer layer of the films, took an α-form in solutions of pH≤12 and a β-form in those of pH≥13. These α- and β-Ni(OH)2 in the films were oxidized to γ-NiOOH·NiO2 and β-NiOOH with increasing potential, respectively.抄録全体を表示PDF形式でダウンロード (1334K) -
尹 鐘大, 須藤 一, 根本 実, 越後谷 淳一1983 年 47 巻 1 号 p. 48-54
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーChanges in hardness and microstructure during aging at 773 K (500°C) of a 3.5 GPa grade maraging steel having the concentration of 8%Ni-14%Mo-20%Co-58%Fe with or without pre-cold-working after quenching from 1623 K (1350°C) have been observed by transmission electron microscopy and electron diffraction. Results obtained are as follows:
(1) The hardness increased rapidly after short time aging. In these specimens modulated structures have been observed. The wave length was several nano-meters and increased by pre-cold-working.
(2) The wave length of modulated structures in over-aged specimens aged for 300 h was about 50 nm, and M2Mo (Laves phase) particles severel nano-meters in diameter precipitated densely in the Mo-enriched zones in the modurated structure in the in-situ manner. However, the contrast of modurated structure was indistinct, and increase of the wave length during aging was suppressed by pre-cold-working. Consequently, the dispersion of precipitated M2Mo particles was more uniform than that in the specimen without pre-cold-working.抄録全体を表示PDF形式でダウンロード (3696K) -
張 栄武, 根本 実, 須藤 一1983 年 47 巻 1 号 p. 54-61
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーDirectionally solidified γ/γ′ eutectic Ni-Al-Ti alloys with and without Ta were prepared and the mechanical properties were examined. Alloys were melted in Al2O3 crucibles 6 mm in inner diameter using a vacuum Mo furnace, and the crucibles were lowered at various speeds. The oriented structure was obtained by the lowering speed of 2.78 μm/s (10 mm/h). The growth direction of γ and γ′ was ⟨100⟩, and it inclined by 10°-15° from the axes of specimens. The tensile strength showed maximum values at about 973 K (700°C). Compositions of alloys with best mechanical properties are 80.5Ni-11Al-8.5Ti (alloy L) and 81.5Ni-9Al-5.5Ti-4Ta (alloy T) in at%. The high temperature strength of alloy “T” was superior to that of alloy “20” having the composition of 72Ni-15Al-4.5Ta-5Co-1.75V-0.75Re-1W in at% examined by Jakson.抄録全体を表示PDF形式でダウンロード (4420K) -
森 福孝, 三浦 維四1983 年 47 巻 1 号 p. 62-66
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーIn the nucleation and growth process such as the primary recrystallization, the generated grain number and the reaction time have been studied by computer simulation. Homogeneous nucleation, constant nucleation rate, and constant growth rate are assumed. The generated grain number (n) is shown to increase with increasing nucleation rate (N) and decrease with increasing growth rate (G), and the expressions n=1.691(N⁄G)0.6573 for 2-dimensional reaction and n=2.183(N⁄G)0.7102 for 3-dimensional reaction are obtained. Time for reaction (t) is shown to decrease with increasing nucleation rate and growth rate, and the expressions t=1.733(G\sqrtN)−0.6690 for 2-dimensional reaction and t=1.744(G\sqrt[3]N)−0.7342 for 3-dimensional reaction are obtained. The 2-dimensional equation shows a good agreement with experimental data for the recrystallization of commercial pure aluminium.抄録全体を表示PDF形式でダウンロード (644K) -
石原 豪1983 年 47 巻 1 号 p. 67-72
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーA unique type of microstructure was successfully developed in low carbon steel, which is characterized by martensite encapsulating islands of ferrite. Moreover four kinds of fatigue test pieces having different martensitic hardnesses without changing grain size of ferrite, connectivity and the volume fraction of martensite, were made. In these duplx ferrite-martensite microstructures, we studied the relation among the selection ratio of the matrix by the fatigue crack, hardness of the second phase and the microstructure under high mean stress.
The matrix selection ratio of fatigue crack is high at a low hardness ratio (matrix to second phase) and a low stress at the crack tip. But in case of a high stress at the crack tip, the matrix selection ratio by crack is lower than that at a low mean stress, because the microstructure becomes a simple phase and it becomes impossible to be affected by the microstructure.
In case of higher hardness ratio (matrix to second phase) and high mean stress, the selection ratio of crack for matrix propagates with a static fracture mode as cleavage facets, and so the selection ratio is almost the same as in the case of low mean stress. That is to say, the selection ratio does not depend on the stress at the crack tip.抄録全体を表示PDF形式でダウンロード (1358K) -
米谷 茂, 能登谷 久公, 高辻 雄三1983 年 47 巻 1 号 p. 72-79
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーUp to this time, many researches regarding grinding residual stress have been reported. About the distribution of residual stress below the ground surface, large tensile stress is found in the layer neighboring the surface. Usually it is considered that residual stress may mainly be caused by the heat occurring due to the grinding. Simultaneously, it is necessary to consider that plastic deformation generated under the wheel-work contact zone results in the occurrence of residual stress.
In this report, the authors have investigated residual stress from the above view point. We used carbon steel S45C as specimens and measured residual stresses of the specimens ground under various grinding conditions.
We measured plastic distortion at each point of the specimens which were taken out in the process of grinding, and investigated the influence of plastic distortion on the occurrence of residual stresses.抄録全体を表示PDF形式でダウンロード (1009K) -
財満 鎮雄, 鈴木 正志, 南 立作, 山田 茂1983 年 47 巻 1 号 p. 80-89
発行日: 1983年
公開日: 2008/04/04
ジャーナル フリーCBN tool excellent wear resistance is known to be effective for difficult-to-cut materials, but it’s wear property is changed greatly with the material of binder which is selected differently in various manufactures. The wear properties of three kinds of commercial CBN tools binded with Co, Al2O3 and TiN in dry cutting of hypersilumin and heattreated SKD61 were examined experimentally and discussed in relation to EPMA observations of wear surface. Results obtained are as follows:
In cutting hypersilumin, the wear of CBN tool binded with Co, which has smaller affinity with work materials than the CBN tool binded with Al2O3 or TiN, was the smallest in the three kinds of tools. In cutting SKD61, the wear of CBN tool binded with Al2O3, which has small affinity with iron, was the smallest in the three kinds of tools. Long life of CBN tool was caused by the small affinity between the materials of tool and work. CBN tool should be chosen by considering the affinity between the material of tool and work.抄録全体を表示PDF形式でダウンロード (3808K)
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