巻号一覧
51 巻, 1 号
選択された号の論文の15件中1～15を表示しています
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宮川 長二, 羽田 紘一, 後藤 公美1987 年 51 巻 1 号 p. 1-4
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーFine particles of Sr ferrite (SrO·6Fe2O3) have been synthesized by the hydrolysis method of refluxed ethanol solution of Fe(III) and Sr(II) acetylacetonates and subsequent heat-treatments of the precipitates, and their magnetic properties have been studied. The particle size of the present hexaferrite heated at 1173 K for 3.6 ks was about 50-60 nm on average. The coercive force MHC=533 kA·m1 (6700 Oe), one of the highest values reported so far for isotropic SrO·6Fe2O3 samples, has been obtained for this particle-size region. This value of MHC approaches the theoretical limit based on the coherent rotational model of magnetization for an assembly of single-domain particles oriented at random.抄録全体を表示PDF形式でダウンロード (577K) -
井上 尚三, 奥山 佳正, 芳井 熊安, 川辺 秀昭1987 年 51 巻 1 号 p. 5-11
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーIn order to investigate the interfacial microstructure of Al/a-SiC and the interfacial reaction at the temperature range of 573-773 K, Al/a-SiC double layered and a-SiC/Al/a-SiC triple layered films prepared by rf planar magnetron sputtering were studied with transmission electron microscopy (TEM), reflection electron diffraction (RED) and Auger electron spectroscopy (AES).
RED and AES observations of as-deposited layered films found that some thin reaction layer might exist at the Al/a-SiC interface. This interfacial structure did not change with annealing below 573 K. When a-SiC/Al/a-SiC triple layered films were annealed above 673 K, silicon precipitates and Al4C3 layer were formed at the Al/a-SiC interface. The thicknesses of these reaction layers were relatively thin. It was confirmed from in-situ observations with TEM that these silicon precipitates were formed during the heating process up to 673 K, and also that Al4C3 was made durig annealing at 673-773 K.抄録全体を表示PDF形式でダウンロード (2666K) -
井上 尚三, 須崎 嘉文, 芳井 熊安, 川辺 秀昭1987 年 51 巻 1 号 p. 12-17
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーAn a-Si1−XCX film is very interesting material from a viewpoint of an atomic structure, since the carbon atom has two kinds of coordination numbers (three-fold for the graphite structure and four-fold for the diamond structure). The purpose of this study is to investigate the atomic structure of a-Si1−XCX films.
a-Si1−XCX films (0≤X≤0.5) were deposited onto (001) silicon wafers by rf planar magnetron sputtering with composite targets which consist of silicon and graphite. The structures of these films were investigated by IR absorption measurements, X-ray diffraction and transmission electron diffraction, and also the atomic arrengements of a few atomic layers at the surface by reflection high energy electron diffraction (RHEED).
It is shown from IR measurements, X-ray diffraction and transmission electron diffraction that the carbon atoms are distributed uniformly in these films and that the coordination number of carbon atoms is four-fold in the carbon mole fraction range of 0≤X≤0.5. The positions of halo peaks observed in RHEED profiles differ from those observed in X-ray and transmission electron diffraction profiles. From a comparison of these data it can be considered that the distance between the nearest neighbor atoms at the surface is longer than that in the film, and also from the distorted micro-crystalline model it is suggested that the structure in the surface layer is more distorted than in the film.抄録全体を表示PDF形式でダウンロード (1125K) -
吉田 信, 深谷 益啓, 宮崎 亨1987 年 51 巻 1 号 p. 18-23
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーCoarsening behaviors of γ′-precipitates in Ni-Cu-Si ternary alloys have been extensively investigated by means of X-ray diffraction and transmission electron microscopy. Furthermore the propriety of application of a bifurcation theory to coarsening of precipitate particles has been also examined.
The coarsening rates of γ′-particles in Ni-Cu-Si ternary alloys remarkably depended on the composition of alloys; the alloys whose compositions are close to the center of the miscibility gap show extremely low coarsening rates. The coarsening of γ′-precipitates nearly stops when γ′-precipitates grow up to a certain size which depends on the alloy composition; the critical size of γ′-precipitates is small in the alloy close to the center of miscibility gap. These phenomena are successfully understood by the microstructure-bifurcation diagram concerned with the structure-stability, which is established by taking into account the elastic energy and the chemical free energy as well as the interfacial energy as a driving force to coarsening.抄録全体を表示PDF形式でダウンロード (1202K) -
羽木 秀樹, 林 安徳1987 年 51 巻 1 号 p. 24-30
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーThe diffusion coefficient of hydrogen in iron specimens of various interstitial impurity (C, N) contents has been measured at 298 K by an electrochemical permeation method. The diffusivity of hydrogen is significantly reduced by cold-working. In pure iron specimens (high C, N specimens), the diffusivity of hydrogen is slightly restored with increase of Vickers hardness by aging at room temperature. In decarburized-denitrided specimens (low C, N specimens), however, these changes by the aging are not found. Annihilation of dislocations by heat treatments causes recovery of the diffusion coefficient. These results indicate that dislocations serve as trapping sites for hydrogen and formation of the atmosphere of interstitial impurity atoms (C, N) around dislocations weakens the trapping effect of dislocations. In order to evaluate quantitatively the trapping effect of dislocations, the diffusion coefficient of hydrogen has been analyzed on the basis of the trapping theory, and the ratio of the number of the trapping sites to that of total lattice sites (i.e., the so-called trap density) has been calculated. The trap density before the formation of the atmosphere of interstitial impurity atoms is, within experimental error, proportional to the dislocation density.抄録全体を表示PDF形式でダウンロード (1095K) -
松尾 欣枝, 鳥居 靖子1987 年 51 巻 1 号 p. 31-36
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーThe transition process in the β′→ζ transformation of Ag-Zn alloys has been investigated by measuring the electrical resistivity of bulk and melt-spun specimens, and the following results have been obtained.
The transition temperature of melt-spun specimens is lower than that of bulk specimens, suggesting that the transition temperature is affected by quenched in vacancies. Furthermore, the results of the isothermal variation of the electrical resistivity analyzed by using the theoretical equation of Johnson-Mehl indicate that the β′→ζ transition consists of two processes: At the first stage, the coefficient m which is related to the transition mechanism increases linearly with the holding temperature, while at the second stage m is constant at about 2.0.抄録全体を表示PDF形式でダウンロード (695K) -
大橋 鉄也1987 年 51 巻 1 号 p. 37-43
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーBy an analytical method, we examine non-uniform multiple slip near a grain boundary plane in fcc bicrystals. To analyse the multiple slip deformation, we develope a new computer code of finite element structure analyses that utilizes models for movement and interaction of dislocations to have a quantitative constitutive relation for fee crystals. In this method, the critical resolved shear stresses for activation of slip systems are assumed to be given by a linear combination of twelve functions that are proportional to 1/2 power of the density of accumulated dislocations on slip systems. And these functions are weighted with constants which represent interaction intensity between dislocations on twelve slip systems.
We analyse deformation of isoaxial bicrystals of nominal strain incompatible type and discuss in detail on the formation process and structure of the multiply slipped region. Results of the analyses are summarized as follows:
(1) At a very early stage of the activation of secondary slip systems, shear strain on the systems is in the order of 10−7 and it is about 1/100 of the one on the primary system.
(2) At a deformation stage when the nominal strain is about 12 times as large as the one at the elastic limit, the multiply slipped region consists of rather uniform distribution of shear strain on the primary slip system and non-uniform shear strain on the secondary systems. Shear strain on the secondary systems range from 10−7 to a value comparable to the one on the primary system.
(3) When the interaction intensity between moving and forest dislocations is doubled, the growing rate of the multiple slip region and shear strain on the secondary systems are reduced to about 1/1.6 and 1/2, respectively.抄録全体を表示PDF形式でダウンロード (1102K) -
鄭 敏輝, 幸塚 善作1987 年 51 巻 1 号 p. 44-50
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーThe thermodynamic properties of the liquid In-Bi-Pb system have been determined from galvanic cell measurements on five pseudobinary systems of fixed NBi⁄NPb molar fraction ratio. The cells used were as follows:
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The emf measurements were carried out in the temperature range of 923-1123 K. The activities and the partial molar properties of indium were determined from the experimental data. From the partial properties of indium the excess integral properties of the ternary alloys were calculated by means of Darken’s method, and the activities of bismuth and lead were calculated by using Gibbs-Duhem equation. The excess free energies of the ternary alloys are slightly positive in the composition range NBi<0.1 and exhibit negatively large values as the molar fraction of bismuth increases.
The ternary excess free energies calculated from related binary data by means of the Kohler, the Toop and the Jacob and Fitzner equations which are based on the regular approximation do not agree with the experimental results. By assuming the pseudobinary systems of fixed NBi⁄NPb to be regular solutions the authors derived a new equation for predicting ternary excess free energies. The calculated ternary free energies from the equation agree well with the experimental results.抄録全体を表示PDF形式でダウンロード (907K) -
常光 幸美, 大野 湶, 春山 志郎1987 年 51 巻 1 号 p. 51-56
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーAmorphous Co-P alloys have been deposited by d.c. and pulse plating from Watts-type Co plating bath containing phosphorous acid, and their electrochemical properties in sulfuric acid solution have been studied by means of electrochemical polarization and impedance measurements. Pulse conditions were found to have profound effects on the nature of the deposits. In particular, the Co-P alloys pulse-plated at low duty cycles, namely electrodeposited at high activation overpotentials, exhibited an amorphous alloy phase having a high degree of homogeneity, in spite of their very low phosphorus content less than 4.0 mass%P compared with those of d.c.-plated Co-P alloys. The amorphous Co-P alloys exhibited high corrosion resistance in contrast with pure Co deposit. This may be attributable to the formation of a uniform protective film containing phosphates. The electrocatalytic activity of the amorphous Co-P alloys for cathodic hydrogen evolution was one order of magnitude higher than that of pure Co, although the exchange current density was considerably low. This high activity for hydrogen evolution can be ascribed to the low Tafel slope, which is originated from the reaction mechanism. The amorphous Co-P alloys, having high corrosion resistance and high electrocatalytic activity for hydrogen electrode reaction, can possibly be used as cathode material for water electrolysis.抄録全体を表示PDF形式でダウンロード (1444K) -
石田 章, 小川 一行, 武井 厚1987 年 51 巻 1 号 p. 57-62
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーTiC was deposited on SUS 304 stainless steel by ion plating, and it was found that film adherence was improved by ionization. To determine the effect of ionization, the composition and microstructure of the TiC coating films deposited at various probe currents were investigated using an electron probe microanalizer (EPMA), auger electron spectroscopy (AES), transmission electron microscopy and selected area electron diffraction. From the results of EPMA and AES, the composition was not changed by ionization. On the other hand, the electron diffraction patterns of the ion-plated TiC coating films on SUS 304 showed that many TiC grains coherent to the substrate were formed at the TiC-SUS 304 interface by ionization. The epitaxial TiC grains seemed to contribute to improvement of the adherence of the TiC film.抄録全体を表示PDF形式でダウンロード (1564K) -
八百 周作, 加来 久幸, 中村 崇1987 年 51 巻 1 号 p. 63-69
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーAg-Zn alloys containing Zn over a range of 7.0 to 86.4 mass% were exposed at 303 K and 353 K in N2-O2 atmospheres containing 1 vol%H2S and 2-90% relative humidity. Corrosion product layers on the Ag-Zn alloys after exposure were investigated using AES and XPS. It was found that there was a good agreement between depth profiles of AES and XPS. Ag2S was a main product on the alloys containing less than 25.4 mass%Zn. ZnS as well as Ag2S was found at the surface of corrosion product layer on the alloys containing more than 35.5 mass%Zn. The presence of ZnO was confirmed near the boundary between the corrosion product layer and the alloy. O1s spectra of XPS suggested the presence of thin ZnSO4 layer adjacent to ZnO layer. The statistical analysis of AES data was in reasonable agreement with the results obtained by XPS.抄録全体を表示PDF形式でダウンロード (896K) -
斎藤 守正, 須藤 恵美子1987 年 51 巻 1 号 p. 70-75
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーFor the determination of the amounts of oxygen up to the level of 1 ppm in zone-refined iron, the vacuum fusion method using Si was studied.
When 0.07-0.15 grams of pure Si were added into the graphite crucible at 2073 K, the oxygen blank values from the crucibles were reduced under 0.5 μg/600 s, and consequently the oxygen in pure iron was able to be rapidly determined. The procedures were as follows: After degassing the graphite crucible for 7.2 ks at 2473 K, the temperature of the crucible was redued to 2023 K and Si was added into the crucible, degassing being made for 1.2 ks at this temperature. The electropolished samples of 5-10 g were next added into the crucible and gases were collected for 600 s.
The usable amount of Si for the determination of oxygen in pure iron must not exceed 3 mass% because of the influences of Si on the determination of oxygen. In addition, large samples (surface area: less than 10×10−4 m2) were necessary to be used in order to minimize the sample contamination. Thus the crucibles were improved: The size of the inner crucible was 25 mm in diameter, 70 mm in height and 3 mm in thickness and the size of inlet of the crucible funnel was 18 mm in diameter.
This method was applied to the determination of oxygen in pure iron refined under the several zone conditions. The oxygen contents was found to be varied according to the zone-refined conditions and the location of zone-refined iron. The precision of this method was 7.2% with the relative standard deviation at the oxygen concentration of 2.2 ppm.抄録全体を表示PDF形式でダウンロード (765K) -
浅山 行昭, 川瀬 嘉孝, 岡田 真樹, 望月 俊男, 坂下 修一1987 年 51 巻 1 号 p. 76-82
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーThe relation between mechanical properties and heat-treatment was studied on an Fe-3Cr-14Ni-3Mo-1.5Ti steel. The steel is a new cobalt free maraging steel in which deterioration of toughness introduced by formation of low temperature precipitates associated with the presence of titanium is suppressed by addition of chromium.
When the steel is annealed at comparatively low temperature, the toughness of the steel after aging decreases with the effect of Laves phase present undissolved in the matrix. However, the steel annealed at a high temperature at which the Laves phase dissolves into the matrix shows excellent properties as follows, when aged at 783 K for 1.8 ks.
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山元 洋, 永倉 充, 斉藤 雅彦1987 年 51 巻 1 号 p. 83-90
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーIn melt-spun ribbons of Ce-(Fe, Co)-(B, Si) system alloys prepared by the single roller method, the effects of composition, substrate surface velocity and subsequent annealing on the magnetic properties were studied. The maximum coercivity (IHC=672 kA/m) and the magnetic energy product ((BH)max=33.6 kJ/m3); were obtained in a Ce20Fe70B10 ribbon prepared at a substrate surface velocity of 11.8 m/s. X-ray diffraction patterns from samples of the highest coercivity show a mixture of an amorphous and a fine crystalline phase.
In Ce20(Fe1−zCoz)70B10 system ribbons, as the Co content is increased, the coercivity tends to decrease, while the Curie temperature is raised, In Ce20Fe70(B1−wSiw)10 system ribbons Si substitution increases the coercivity as well as the magnetization. It is also found that the addition of Si tends to facilitate the fabrication of longer ribbons.抄録全体を表示PDF形式でダウンロード (1312K) -
渡邊 清1987 年 51 巻 1 号 p. 91-94
発行日: 1987年
公開日: 2008/04/04
ジャーナル フリーThe relations between the order-disorder transformation and the permanent magnet properties of iron and platinum alloys have been investigated.
An Fe-36 at%Pt alloy which is low in coercivity and is remarkable in the effect of heat treatments, has been investigated. The results show that the water-quenched γ single phase exhibits the typical soft magnetic properties. On aging at temperatures between about 770 and 870 K, the γ single phase is changed into a γ+γ1 phase, where the magnetization is not easily saturated for the high crystal magnetic anisotropy of the γ1 phase and the coercivity shows a low value. On aging at 903 K, the alloy of a γ1 single phase giving rise to broad diffraction lines exhibits the highest value of Hc=135 kA·m1. The ordering of the γ1 phase is advanced with the rise of aging temperature, while the coercivity rapidly falls.
It is presumed that the origin of the excellent permanent magnet properties of the Fe-Pt alloy are related to the existence of the constitutionally very imperfect γ1 phase and the low ordering state, and these are caused by the pinning in the magnetic domain wall.抄録全体を表示PDF形式でダウンロード (510K)
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