巻号一覧
57 巻, 6 号
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高橋 裕1993 年 57 巻 6 号 p. 597-603
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーA new method to calculate the atomic structure of equilibrium and the balanced state in crystalline materials bonded with a pair potential was developed. In such a state, the potential energy of the system is minimized and corresponds to the static state at 0 K.
The method is based on the principle of the minimum potential energy and its formulation is quite similar to the finite element method (FEM) in structural mechanics. The interaction between two atoms is approximately expressed by a linear equation of which matrix should be modified for convergency. It is termed a stiffness equation in FEM. An overall stiffness equation is constructed by assembling these atom-atom interactions. The large linear equation is solved by conventional calculus.
Hydrostatic pressure and uniaxial tension problems in a two-dimensional Lennard-Jones crystal are solved to check the validity of the method. The calculated results for small clusters showed good agreement with analytical solutions for infinite models.
The method is expected to apply to statics problems of some kinds of lattice defects.抄録全体を表示PDF形式でダウンロード (657K) -
渡辺 万三志, 堀田 善治, 藤波 隆善, 佐野 毅, 根本 実1993 年 57 巻 6 号 p. 604-611
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーThe energy dispersive X-ray microanalysis in an analytical electron microscope (AEM-EDS) which provides a high spatial resolution was used to measure interdiffusion coefficients in the Ni-Al binary system. Electron transparent thin specimens were prepared from a Ni/Ni-8 mol%Al diffusion couples. A modified technique was introduced to avoid breaking at the couple interface during preparation of thin specimens. The absorption correction required for the AlKα line was achieved by the differential X-ray absorption (DXA) method. A comparison showed that the agreement was fairly good between the results of the AEM-EDS and the electron probe microanalysis (EPMA). Thus, it was suggested that AEM-EDS can be used for the measurement of interdiffusivities as an alternative to EPMA, particularly at lower temperatures where a high spatial resolution is required. The interdiffusivities measured in this study are compared with other reported values. The interdiffusivities of this study are consistent with the impurity diffusivities of Al in Ni reported in other studies, but higher by an almost order of magnitude than the reported self-diffusivities of Ni in Ni. The diffusion periods and temperatures necessary for AEM-EDS were discussed in comparison with those for EPMA.抄録全体を表示PDF形式でダウンロード (752K) -
吉冨 康成, 岩山 健三, 黒木 克郎, 松尾 征夫, 増井 浩昭1993 年 57 巻 6 号 p. 612-620
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーSecondary recrystallization of Fe-3%Si alloy containing AlN and MnS precipitates, which is usually given a heavy reduction at the final cold-rolling stage, was investigated with special reference to an influence of annealing of hot-rolled band before first cold rolling. In the annealing process of hot-rolled band, fine carbides or nitrides with 10∼20 nm in diameter precipitated, resulting in increasing the dislocation density with tangling dislocations around those precipitates. Accordingly, on the annealing stage after the first cold-rolling, the recrystallized microstructure was finer and more homogeneous. In addition, a decrease in {211}⟨011⟩∼{100}⟨011⟩ (RD\varparallel⟨011⟩) oriented grains and an increase in {111}⟨112⟩ ones occurred. Annealing of hot-rolled band is probable to have an important effect on enhancement of {110}⟨001⟩ secondary recrystallized grain growth, because of more {111}⟨112⟩ primary recrystallized grains, which has Σ9 coincidence orientation relationship to the {110}⟨001⟩ orientation.抄録全体を表示PDF形式でダウンロード (1321K) -
井口 征夫, 後藤 千寿子, 柳沢 満, 斉藤 文夫1993 年 57 巻 6 号 p. 621-627
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーComputer color mapping for the preferential growth of secondary recrystallized Goss grains at an incipient stage during secondary recrystallization in the grain oriented silicon steel sheet was performed with an image analyzer, using crystallographic orientation data measured by a Kossel examination.
The results are summarized as follows.
(1) With secondary recrystallization annealing for 3 h at 850°C, secondary recrystallized Goss grain in an ellipitcal form of 80 μm in the rolling direction and 50 μm in the transverse direction grew preferentially at 1/10 depth beneath the surface of the silicon steel sheet.
(2) With secondary recrystallization annealing for 7 h at 850°C, four secondary Goss grains coalesced to 100-350 mm in size grew preferentially in a state elongated in the rolling direction.
(3) The deviation angle of orientation of these coalesced secondary Goss grains was within 2 degrees.
(4) It is considered that the preferential growth of secondary recrystallized Goss grains at an incipient stage of secondary recrystallization annealing took place in the defined zones at 1/10 depth beneath the steel surface, these zones being inherited by the structure memory near the surface of the hot-rolled silicon steel sheet.抄録全体を表示PDF形式でダウンロード (683K) -
村山 洋之介, 三上 雅人, 石山 成志, 花田 修治1993 年 57 巻 6 号 p. 628-636
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーMechanical properties of α Ti are strongly influenced by texture and oxygen content. The effect of texture and oxygen content on the deformation behavior was investigated using three kinds of textured Ti sheets containing 0.05, 0.1, 0.2 and 0.4 mass%O. Especially, we paid attention to deformation twinning and ⟨c+a⟩ slip. Consequently, it was found that occurrence of deformation twinning is suppressed and ⟨c+a⟩ dislocations become operative as the oxygen content increases. Therefore, anisotropy in mechanical properties due to the deformation twinning disappears as the oxygen content increases. However, the operation of ⟨c+a⟩ slip having high critical resolved shear stress leads to easy cleavage fracture and reduced elongation.抄録全体を表示PDF形式でダウンロード (1907K) -
中佐 啓治郎, 佐藤 博史, 西山 文隆1993 年 57 巻 6 号 p. 637-644
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーCharpy impact tests were carried out on the Ti-15V-3Cr-3Al-3Sn (15-3-3-3) and Ti-13V-11Cr-3Al (13-11-3) alloys which were hydrogen-charged in sulfuric acid solution with a concentration of 0.5 kmol/m3 under a charging current density of 1000 A/m2.
Hydrogen charging resulted in a decrease in Charpy impact energy for the as-solution treated 15-3-3-3 alloy at temperatures lower than 300 K and for the aged alloy lower than 700 K. For the aged 13-11-3 alloy, the impact energy decreased slightly by hydrogen charging at all the testing temperatures. The aged 15-3-3-3 alloy was higher in the hydrogen concentration CH than the as-solution treated one and the aged 13-11-3 alloy, and the alloys did not show any change in CH by heating up to 700 K. The hydrogen charging promoted the cleavage fracture of the as-solution treated 15-3-3-3 alloy and the aged 13-11-3 alloy, and the quasi-cleavage fracture of the aged 15-3-3-3 alloy.抄録全体を表示PDF形式でダウンロード (1698K) -
佐貫 須美子, 高田 和博, 新井 甲一, 砂田 聡, 杉山 明夫, 真嶋 宏1993 年 57 巻 6 号 p. 645-651
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーExperimental studies were conducted to elucidate a possible mechanism for the reductive stripping-precipitation of ultrafine particulates of Au from Au(III)-loaded MIBK. The principal findings are as follows: (1) Under the irradiation of day light, the yellow color of Au(III)-loaded MIBK fades gradually at the same time, the equilibrium potential shifts towards the noble direction, suggesting the decomposition of (H+MIBKAuCl4−)o into (H+MIBKAuCl2(OH)2−)o or (H+MIBKAuCl2−)o via a photochemical route. (2) Water acts as a reductant of Au(III)-loaded MIBK under the catalytic action of a small amount of a suitable reducing agent to precipitate ultrafine particulates of Au. (3) The role of H+ or Cl− on the reductive stripping-precipitation reactions was also studied. The rate of reductive stripping-precipitation of Au increases with the increase in temperature under the presence of NaCl, exhibiting an activation energy of 43.7 kJ·mol−1.抄録全体を表示PDF形式でダウンロード (700K) -
下尾 聰夫, 陳 和民, 岡村 清人1993 年 57 巻 6 号 p. 652-658
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーThe effect of thermal history on pyrolysis of Si-C-O fibers coated with oxide films was investigated. The fibers were oxidized at 1373, 1573 and 1773 K to form an oxide film about 4.7×10−1 μm in thickness, and were quenched to room temperature. These oxidized fibers (named fiber-a, -b and -c respectively) were heated rapidly up to 1573, 1673 and 1773 K in Ar. During these heat treatments, mass changes of the fibers were measured with a thermobalance method. The heat-treated fibers were examined by X-ray diffraction, SEM observation and the tensile test.
At 1773 K, fibers-a and -b pyrolyzed completely, while the growth and coasening of β-SiC was not observed in fibers-c. Pyrolysis of cores of the fibers took place, due to both the preferential oxidation of free carbon and the crystallization of the oxide film into cristobalite. The tensile strengths of the as-oxidized fibers were about 80% of that of the original fibers. Fibers-c heated in Ar at 1773 K retained 56% of that of the original fibers. This gradual reductions in strength were caused by the formation of surface defects, such as cracks and pits. The oxide film formed at 1773 K was found to be resistant to the thermal stress and to be effective for suppressing the pyrolysis of Si-C-O fibers.抄録全体を表示PDF形式でダウンロード (1009K) -
加藤 雅敏, 榊 孝1993 年 57 巻 6 号 p. 659-665
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーThe effect of purity on corrosion behaviour of Cr in various acid solutions was investigated by measuring the polarization curves, change in corrosion potential with time and corrosion rates. HCl, HCOOH and HNO3 solutions were used as corrodents.
High purity Cr of more than 99.9 mass% exhibited high corrosion resistance in HCl solutions. With an increase in purity of Cr, the active dissolution current and the passive current were decreased. Therefore, corrosion potential easily sifted to the passive area from the active dissolution area, and the corrosion resistance increased with purification.
Investigations showed that the effect of purity on the corrosion resistance of Cr in HCOOH solutions was also same as that in HCl solutions.
On the other hand, the corrosion rate of Cr in HNO3 solution was not affected by the purity of Cr. Because the corrosion potential of Cr in HNO3 solution was in the passive or transpassive area due to an oxidation power of the NO3− ion, the corrosion resistance of Cr in HNO3 solutions was irrespective of the purity of Cr.抄録全体を表示PDF形式でダウンロード (624K) -
谷口 滋次, 柴田 俊夫, 加藤 直樹1993 年 57 巻 6 号 p. 666-673
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーTiAl coupon specimens were coated with sol-derived SiO2 films of about 0.2 μm thickness and subjected to oxidation tests at 1100, 1200 and 1300 K in a flow of purified oxygen under atmospheric pressure.
At 1100 and 1200 K the oxidation was suppressed very much by applying the coating. This is attributable to the formation of alumina layers beneath the coating. The formation of the protective alumina layer can be explained in terms of the slow diffusion of oxygen through the coating which can favor the preferential oxidation of aluminum. However, at 1300 K the coating suppresses the oxidation a little during the initial oxidation period, after which its protectiveness decreases as the oxidation proceeds. This can be explained by the diffusion of oxygen which is enhanced by the temperature rise and the development of mechanical failure in the coating which may be caused by the oxide growth.抄録全体を表示PDF形式でダウンロード (1348K) -
井上 亮, 後藤 良三, 水渡 英昭1993 年 57 巻 6 号 p. 674-678
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーThe study on the determination of ultra low content of carbon was made by using ion-chromatography, coupled with the combustion method in an oxygen gas stream. A considerable increase in the variation of conductivity with the content of carbonate ion was observed because of the high ionic conductivity of OH− in NaOH eluent. The Na+ (OH−) ion could be removed by a cation exchange column according to the reaction: R-H++NaOH→R-Na++H2O. Therefore, carbonate ions in the NaOH absorbent, which absorbed CO2 gas produced by the reaction of carbon in metal with oxygen gas, could be concentrated on the concentration column. It was found that 1.67 mass ppm of carbon in a pure iron sample was determined within the accuracy of 0.24 mass ppm of standard deviation.抄録全体を表示PDF形式でダウンロード (421K) -
金 得圭, 金子 純一, 菅又 信1993 年 57 巻 6 号 p. 679-685
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーPowders of metal oxides of different standard free energies of formation, CuO, Fe2O3, SiO2 and MgO, were mechanically alloyed with pure aluminum powder by a high energy ball mill under an argon atmosphere. P/M materials were fabricated from mechanically alloyed powders by cold pressing, vacuum degassing and hot extrusion. The solid state reaction of aluminum-oxide systems was studied by DSC analysis and X-ray diffraction. Thermit reaction occurs in Al-CuO and Al-Fe2O3 systems during mechanical alloying and hot extrusion, respectively. In the case of SiO2 and MgO which have a relatively high standard free energy of formation, no reaction with aluminum occurs even after heating of P/M materials at 873 K for 24 h. It is shown by X-ray diffraction and DSC analysis that the Al-CuO system P/M material consists essentially of the Al-Cu alloy matrix with dispersion of Al2O3. The hardness increase by age hardening for Al-CuO P/M material after solutionizing and water-quenching is about half as much as that of I/M Al-Cu alloys. The P/M material of the Al-CuO system shows the highest tensile strength of 600 MPa at room temperature, whereas that of the Al-Fe2O3 system has the highest tensile strength of 330 MPa at 573 K.抄録全体を表示PDF形式でダウンロード (1323K) -
李 明勲, 長谷川 恭孝, 沖 猛雄1993 年 57 巻 6 号 p. 686-691
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーAl thin films were prepared on SPCC steel substrates by a thermo-electron activation ion plating process. The influence of argon gas pressure and substrate bias voltage on the crystal orientation and morphology of the films was determined by using X-ray diffraction and scanning electron micrography (SEM), respectively. And the effect of crystal orientation and morphology of the Al thin films on corrosion behavior was estimated by measuring the anodic polarization curves in deaerated 3%NaCl solution.
The crystal orientation of the Al films deposited at high argon gas pressure exhibited a (200) preferred orientation, regardless of the substrate bias voltage. Film morphology changed from a columnar to a granular structure with the increase of argon gas pressure. The morphology of the films depended not only on argon gas pressure but also bias voltage; i.e., the effect of increasing bias voltage was similar to that of decreasing argon gas pressure. The Al films which exhibited the (200) preferred orientation and the granular structure showed good corrosion resistance. Especially, the corrosion resistance of the film prepared with the bias voltage of −2.0 kV and the argon gas pressure of 7.3×10−1 Pa was better than a rolled plate of 99.99%Al. That is, this showed that the corrosion resistance of the Al thin films can be changed by controlling the crystal orientation and morphology. It appears well established that the properties of the Al films prepared by the thermo-electron activation ion plating process depend on the deposition conditions.抄録全体を表示PDF形式でダウンロード (765K) -
薩田 寿隆, 原田 展道, 長谷川 正, 浅井 滋生1993 年 57 巻 6 号 p. 692-698
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーEleven kinds of metals, i.e. Al, Ti, V, Fe, Ni, Cu, Zr, Nb, Mo, Ta and W, were adopted as electrodes and atomized by utilizing discharge taking place between electrodes of the same metal set in deionized water. By examining the composition of produced particles, the metals could be classified into two groups; from the group consisting of the metals/Zr, Al, V, Nb, Fe, Ta, Ti/oxides were produced, and from the group consisting of the metals/Mo, W, Ni, Cu/oxides were not obtained. The produced particles showed various shapes which were peculiar to each metal. From the observation of discharge behaviour, it was found that an electrolysis and a transient arc discharge take place alternatively in all of the metals. In the case Zr, ZrO2 which provides an additional short period of stable arc discharge and finally an insulating state was observed at the edge surface of the cathode.抄録全体を表示PDF形式でダウンロード (886K) -
寺崎 俊夫, 秋山 哲也, 穴見 敏也1993 年 57 巻 6 号 p. 699-705
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーThis paper deals with the method to estimate the strength of the bonded face at which singular stress distributions are caused.
Brazing and adhesive joints were prepared to obtain the strength of the bonded face experimentally.
The authors propose the energy release rate g at the imaginary crack tip to estimate the strength of the bonded face. From the theoretical and numerical analises by using BEM, the energy release rate exponent to imaginary crack length “m” was proposed as 2nd parameter to estimate the strength of bonded dissimilar materials.
The results obtained from applying these two parameters to estimate the experimental strength are as follows.
1) The energy release rate g-value at the imaginary crack tip located at the end of the bonded face is useful for estimating the strength of the bonded face between dissimilar materials.
2) When the difference between the m values of specimens are small, the author’s method for estimating the strength has a potentiality to estimate the strength among the different shaped specimens.抄録全体を表示PDF形式でダウンロード (811K) -
小川 一行1993 年 57 巻 6 号 p. 706-713
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーA yttria dispersed iron alloy with the composition of 2 mol%Y2O3 have very strong tensile strength of 350 MPa. The interface structure of the iron-yttria in the materials was investigated by X-ray diffraction and electron prove microanalysis (EPMA). However, the observation shows no chemical reaction layers of yttria and iron formed in the boundary region. The microstructures of the interfaces in the (001)Y2O3/(001)Fe, (111)Y2O3/(111)Fe and (152)Y2O3/(111)Fe planes were means of the high-resolution electron microscope (HREM). In the cases of (001)Y2O3/(001)Fe and (111)Y2O3/(111)Fe planes, these were formed lattice images of about 10 nm layers at the interfaces. These now spots of the optical diffraction correspond to these lattice images show 0.35 nm and 0.29 nm, respectively. These images of the interlayer estimate chemical reaction layer. The reaction layer is contributed to relaxation at the boundary of Y2O3 and Fe. The narrow reaction layer causes the strong tensile strength of this material.抄録全体を表示PDF形式でダウンロード (1256K) -
真島 一彦, 長谷川 万希子, 勝山 茂, 三島 信, 永井 宏1993 年 57 巻 6 号 p. 714-720
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーNi-Zn ferrite is a promising material as the substrate for thin film magnetic recording heads. The influence of specimen composition and partial oxygen pressure (PO2) in sintering atmosphere (N2+O2) on the microstructure and magnetic properties of Ni-Zn ferrite has been investigated by SEM and XPS. The results obtained are summarized as follows.
(1) ZnO precipitates were observed at the grain boundaries, especially at the triple points of the Ni-Zn ferrite specimen sintered at 1453 K for 10.8 ks under 20% PO2. Such precipitates, however, were not detected in the specimen sintered in the atmosphere whose PO2 was 25%.
(2) Although the permeability (μ) and the resistivity (ρ) of the Ni-Zn specimens sintered at 1453 K for 10.8 ks under 10 to 100% PO2 increased with increasing PO2, both the loss coefficient (Q) and the relative loss coefficient (tanδ⁄μ) showed an optimum value under 20% PO2.
(3) The 0.3 mol% increment of ZnO and the 0.3 mol% decrement of NiO than the conventional composition (Fe2O3: 49.7 mol%, ZnO: 32.6 mol%, NiO: 17.7 mol%) prevented ZnO precipitation on the Ni-Zn ferrite specimen sintered at 1453 K for 10.8 ks in air.
(4) The HIP’ed specimen after sintered at 1423 K, 30 K lower than the conventional sintering temperature of 1453 K, in air showed neither ZnO precipitation nor pores.抄録全体を表示PDF形式でダウンロード (791K) -
熊谷 正樹, 渋江 和久, 金 睦淳1993 年 57 巻 6 号 p. 721-725
発行日: 1993年
公開日: 2008/04/04
ジャーナル フリーThe influence of chlorine, sodium and oxygen in TiAl on oxidation behavior has been studied by using reactive-sintered Ti-33.5 mass%Al-2.5 mass%Mn made from various raw powders.
As the chlorine content in reactive-sintered TiAl-Mn increases, the mass gain after the oxidation test at 1223 K for 86.4 ks decreases. The TiAl-Mn containing more than 500 ppm chlorine has excellent oxidation resistance owing to the protective Al2O3 film formed on the surface at an early stage of oxidation. Chlorine in the TiAl-Mn exists as NaCl particles which are introduced from the Ti powder produced by the Hunter method.
Moreover, halogen such as fluorine and bromine has been found to improve the oxidation resistance of TiAl-Mn.抄録全体を表示PDF形式でダウンロード (746K) -
飴山 惠, 柳田 美由紀, 時実 正治1993 年 57 巻 6 号 p. 726-727
発行日: 1993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 (192K)
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