巻号一覧
58 巻, 8 号
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菅原 茂夫, 渡辺 慈朗1994 年 58 巻 8 号 p. 843-846
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーThe (111) surface of copper crystal was etched for 10 s at temperatures 270 to 290 K with Marukawa’s etchant containing FeCl3·6H2O 0.88 kmol·m−3, HCl 4.4 kmol·m−3 and HBr 0.12 kmol·m−3. The dissolved thickness of matrix surface S was determined by a two-beam interferometric measurement of the step height produced at the boundary between neighboring areas exposed and unexposed to the etchant. The width h and depth d of etch pits of triangular pyramidal shape developed at screw dislocation sites were measured by replica electron microscopy. The lateral dissolved length and the normal dissolved depth at the dislocation sites, H and D, were determined from S, h and d, respectively.
As the etching temperature was raised, all of H, D, D/H and S increased monotonically. It was shown that these results could be explained qualitatively on the basis of the spiral theory of crystal dissolution at screw dislocation and the two-dimensional nucleation theory at dislocation-free surface, respectively.抄録全体を表示PDF形式でダウンロード (530K) -
山本 悟, 若林 利幸, 小林 久芳1994 年 58 巻 8 号 p. 847-854
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーIn the present work the solid solubility, compound formation and strength in Fe alloys have been examined by the calculation of energy and Mulliken’s population of cluster models by the extended Hückel method.
The results of the present work are as follows:
1) The stability of alloy systems and the nature of chemical bonds between Fe atoms and alloying atoms can be estimated based on the cohesive energy, atomic bond populations and atomic populations.
2) The tendency of mutual solid solubility, insolubility and compound formation in Fe alloys can be judged as follows:
a) In the case of elements which make compounds and have no mutual solubility with Fe, the change of cohesive energy with the composition deviates markedly from lineality and the nature of chemical bonds is ionic or covalent.
b) In the case of elements which make compounds and have mutual solubility with Fe, the change of cohesive energy with the composition deviates a little from lineality and the nature of bonds is the mixture of (an ionic or covalent bond) and a metallic bond.
c) In the case of elements which make no compounds and have mutual solubility with Fe, the cohesive energy changes linearly with the composition and the nature of bonds is a metallic bond or its mixture with a covalent or ionic bond.
d) In the case of elements which make no compounds and have no mutual solubility with Fe, the change of cohesive energy with the composition deviates a little from lineality and the nature of bonds is anti-bonding.
3) The hardening ability of solute atoms in Fe alloys may be attributed to the (covalent+ionic) part in the nature of chemical bonds between Fe atoms and solute atoms.抄録全体を表示PDF形式でダウンロード (760K) -
山本 悟, 若林 俊幸, 小林 久芳1994 年 58 巻 8 号 p. 855-864
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーIn the present work, the cohesive energy and energy fluctuation of cluster models have been calculated by the extended Hückel method and the stability of substances has been discussed by the use of these quantities. The results of the present work are as follows:
1) The cohesive energy of a cluster changes with the change of lattice parameter and shows its maximum at the position of actual lattice constant.
2) The cohesive energy and energy fluctuation of a cluster change linearly with the chemical composition in complete solid solution systems. On the other hand, they show the maximum or minimum at the composition corresponding to compounds in compound-forming systems.
3) The cohesive energy and energy fluctuation are the physical quantities useful for a measure of static and dynamical (reactive) stabilities, respectively. For example, the aging-behaviour of Al-Cu, Al-Zn and Al-Ag systems cannot be understood with the help of either of these two quantities but can be reasonably understood only through the simultaneous usage of them.
4) The cohesive energy and energy fluctuation reflect the nature of chemical bonds. The former increases and the latter decreases in the order of metallic bond, electrostatic bond and covalent bond. Thus, these quantities can be used to judge the nature of chemical bonds together with Mulliken’s population.抄録全体を表示PDF形式でダウンロード (1237K) -
細田 秀樹, 里 達雄, 手塚 裕康, 三島 良直, 神尾 彰彦1994 年 58 巻 8 号 p. 865-871
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーThe substitution behavior of additional elements in the L12-type metastable intermetallic compound of Al3Li (δ′ phase) is investigated for the Al-Li alloy design based on the relative internal energies of the Al3Li phase with various defect structures. The Al-Li alloys containing δ′ phase are expected to be a new class of structural materials with low density and high specific strength. In the conventional Al-Li alloys the contents of aluminum are higher than the stoichiometry of 75 mol%Al and the precipitation of the Al3Li phase is effective in increasing the mechanical strength of Al-Li alloys. A prediction method has been developed for the substitution behavior of ternary elements and the type of defect structures of the Al3Li phase at offstoichiometric compositions and the pseudo-ground state. The substitution type defect (or antistructure type defect) is found to be preferred, and most of transition metals substitute only for Li atoms at all compositions investigated. Ca and Sr are predicted to be useful as low-density alloying elements for improving the properties of Al-Li alloys based on the results of the present investigation.抄録全体を表示PDF形式でダウンロード (598K) -
山本 広－, 井上 泰1994 年 58 巻 8 号 p. 872-881
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーStudies were made of the effect of alloying elements on the grain boundary embrittlement of commercially pure iron (from electrolytic iron; C content∼0.002 mass%, O content∼0.015 mass%, S content∼0.006 mass%) by Charpy tests and AES analysis of impurities at grain boundaries. Special reference was made to oxygen as oxides. It was found that the improvement of the embrittlement by the addition of C, Al, Mn and Ca is due to the decrease of S concentration at grain boundaries. As a result of the reaction with Mg which is a trace impurity in molten iron, (Al, Mg)xO, possibly MgO·Al2O3 of the cation vacancy type, was formed in the specimens containing Al. On the basis of this result, it was deduced that the diffusion of Mg and Al by cation vacancies easily occur and the preferential nucleation of MgS and Al(N, S) on the outermost MgO·Al2O3 results in the suppression of grain boundary segregation of S. A similar analysis were made on the effect of Mn and Ca.抄録全体を表示PDF形式でダウンロード (1560K) -
吉冨 康成, 増井 浩昭, 原勢 二郎, 高橋 延幸1994 年 58 巻 8 号 p. 882-891
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーIn the presence of AlN and MnS precipitates in an Fe-3%Si alloy, secondary recrystallization characterized by final heavy cold rolling was investigated with special reference to the phenomenon of unstable secondary recrystallization caused by excessive cold-rolling reduction. Excessive cold-rolling reduction produces smaller grains, which are characterized by more {100}⟨025⟩ oriented grains and higher possibility for the {100}⟨025⟩ oriented grains associated with Σ5 coincidence boundaries in the primary recrystallized specimen. An enhancement of the grain growth of the {100}⟨025⟩ primary recrystallized grain is considered to cause unstable secondary recrystallization by reducing the driving force of grain growth for the secondary recrystallized grain. It may be essential for this unstable secondary recrystallization that the presence of two equivalent orientations of the {100}⟨025⟩ oriented grain which is increased with higher cold-rolling reduction, have the Σ5 coincidence orientation relationship with each other.抄録全体を表示PDF形式でダウンロード (1675K) -
井上 博史, 稲数 直次1994 年 58 巻 8 号 p. 892-898
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーQuantitative texture analysis based on the calculation of crystallite orientation distribution functions (ODF) is necessary to accurately evaluate physical and mechanical anisotropies of polycrystal materials. In the ODF calculation, an analytical method using incomplete pole figures measured by the reflection method alone is convenient, particularly for the materials difficult to prepare thin specimens for the transmission method. In the present study, the complete ODF’s including the odd terms for ghost correction were determined from incomplete pole figures by the iterative series expansion method for cubic, hexagonal and tetragonal materials. To check the reliability of this method, they were compared with the ODF’s calculated from complete pole figures by an ordinary method or from incomplete pole figures by other methods.
The ODF’s determined from the incomplete pole figures measured up to a tilt angle of 70° coincided approximately with those determined from the complete pole figures. This method can therefore be utilized for the ODF analysis with sufficient reliability instead of the conventional method using the complete pole figures. As an attempt, the possibility of the ODF analysis from one incomplete pole figure was examined. However, it was found that the quantitatively exact texture analysis was considerably difficult in this case, though preferred orientations could be determined from the ODF obtained. A technique to determine the ODF from the incomplete pole figures measured at adjacent diffraction lines was also tested for the texture of titanium aluminide. The result indicated that the ODF could be exactly determined even from somewhat overlapped incomplete pole figures by reducing the range of measurement in the α angle and simultaneously increasing the number of pole figures.抄録全体を表示PDF形式でダウンロード (801K) -
日比野 敦1994 年 58 巻 8 号 p. 899-904
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーIn SHS, which synthesizes an intermetallic compound from a green mixed powder by propagating the reaction heat, an exothermic reaction rate affects the self-propagation of a combustion wave. The reaction rate in the heat balance equation is expressed in an Arrhenius style as an empirical formula. However, the basis for this expression is not clear and this assumption seems to treat a powder compact as a continuum. In my previous paper, microscopic observation of reaction between Ni and Al particles in SHS was performed and the combustion process was fairly well simulated with a resultant spherical shell model. The expression of the exothermic reaction rate using the same model is investigated here. The rate contains physical properties of component particles and chemical reaction rate constant and it varies depending on the conversion rate which indicates the comsumption of Ni particles. Furthermore, the phase transformations in reaction are also taken into consideration.抄録全体を表示PDF形式でダウンロード (658K) -
八尾(旧姓 大塚) 伸也, 玉置 雄一, 木村 秀雄, 幸塚 善作1994 年 58 巻 8 号 p. 905-912
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーThe SOx gas sensor utilizing beta-alumina as a solid electrolyte has a rigid theoretical background and produces a reliable emf corresponding to SO2 gas partial pressure, PSO2. However, its emf response to a change in PSO2 is not so fast in comparison with that of other electrolytes. In the present study, an attempt was made to improve the chemical properties of the surfaces of Na+-β″-alumina disc by sputtering Ce on the both sides through a stainless steel net and by oxidizing in air.
Before the experiments, the reaction between CeO2 and Na+-β″-alumina was examined as follows; CeO2 and Na+-β″-alumina powder mixtures and a Na+-β″-alumina plate with the Ce thin film sputtered were annealed at 1073 K in air for various periods, respectively, and then subjected to powder and thin film X-ray diffraction analyses with a diffractometer. Diffraction peaks due to the surface structure of the CeO2 thin film whose lattice constant was twice as large as CeO2 were detected; however, any compound was not detected.
The SO2 gas sensor utilizing the β″-alumina disk covered by CeO2 was tested at 873 and 1023 K. The island-like coverage of CeO2 did not reduce a hysteresis of the emf’s at 873 K with a change in PSO2. At 1023 K, the measured emf’s agreed with the theoretical values. The response of the sensor at 1023 K became much faster by the coverage, when PSO2 in the measured gas was decreased in the range of low PSO2; the SO2 gas released from Na2SO4 diffused smoothly. The decomposition of Na2SO4 may become easier when it had grown vertically along the island-like CeO2. It was concluded that CeO2 does not have a harmful effect on the lifetime of the sensor, and improve the properties of SOx gas sensor at a higher temperature.抄録全体を表示PDF形式でダウンロード (782K) -
日比野 委茂, 前 健彦, 鳥山 成一, 砂田 聡, 新井 甲一1994 年 58 巻 8 号 p. 913-921
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーThe effect of Ga content on the characteristics of anodic dissolution behavior of Al-Ga alloys in a NaCl containing dilute NaOH solution was investigated by means of an electrochemical measurement of the polarization curves, immersed corrosion tests and scanning electron microscopic observations of the corroded surfaces for the alloys.
The main results obtained are summarized as follows:
(1) The anodic polarization curves of Al-Ga alloys in the dilute NaOH solution show a typical active-passive transition, and the limiting anodic current density increases with an increase in the concentration of NaOH and solution temperature. However, there is no effect of Ga content in the alloys on the limiting anodic current of the alloys in the dilute NaOH solution. The appearent activation energy for anodic dissolution of the alloys is about 25.84 kJ/mol, and the dissolution rates of alloys are controled by the mass-transport of OH− ions through the boundary layer between the solid and the liquid interface. The corrosion of the alloys is uniform. However, the selective dissolution of Al species from the grain boundary layer of Ga containing specimens is observed.
(2) The pitting potentials of Al-Ga alloys in the NaCl containing dilute NaOH solution depend upon the concentration of NaCl and the Ga content in the specimens. When the NaCl concentration and the Ga content in the alloys are increased, the pitting potentials are shifted to a more basic potential and the pitting resistance of the alloys is decreased. The pitting corrosion rates also increase with increasing Ga content in the alloys in the NaCl containing dilute NaOH solution.抄録全体を表示PDF形式でダウンロード (1421K) -
松原 茂雄, 傅 達博, 中本 一成, 片山 巖, 飯田 孝道1994 年 58 巻 8 号 p. 922-928
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーCalcium fluoride solid electrolyte has been extensively used in galvanic cells for the measurement of fluorine potential to obtain the activity of alloys and compounds, because the ionic transference number of the electrolyte is about unity even at PF2⁄P0=10−62 above 550°C. So far there were no literature data available for the measurement below 500°C by use of the calcium fluoride solid electrolyte.
In this report, a trial has been made to measure the fluorine potential in a molten zinc bath equilibrated with ZnF2 at the temperatures between 450∼500°C using CaF2 cells with some kinds of reference electrode. By use of Bi, BiF3 or Zn, ZnF2 as the reference electrode, the cells respond quickly and stable emf values which agree fairly well with the literature data are obtained. The effects of the atmoshere around the reference electrode and the cell construction on the cell stability and reproducibility have been investigated experimentally.抄録全体を表示PDF形式でダウンロード (532K) -
松原 茂雄, 傅 達博, 中本 一成, 片山 巖, 飯田 孝道1994 年 58 巻 8 号 p. 929-935
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーCalcium fluoride solid electrolyte has been extensively used in galvanic cells for the measurement of fluorine potential to obtain the activity of alloys and compounds, because the ionic transference number of the electrolyte is about unity even at PF2⁄P0=10−62 above 550°C. So far there were no literature data available for the measurement below 500°C by use of the calcium fluoride solid electrolyte.
The purpose of this work is to develop the sensors for the control of aluminum concentration in a hot dip galvanizing bath, which is of industrial importance for producing galvannealed steel sheets. In the previous study we showed that the fluorine potential in a molten zinc bath equilibrated with ZnF2 which was located in the cell at the temperatures between 450∼500°C can be measured successfully by using CaF2 cell with Bi, BiF3 or Zn, ZnF2 as the reference electrode.
In this work, a trial has been made to measure the fluorine potential in molten Zn-Al baths equilibrated with AlF3 at the temperatures between 450∼500°C using CaF2 cells with the above reference electrodes. The initial response of these cells is relatively slow. However, once the cell shows stable emf, the cell responds quickly to the aluminum concentration change. The response time is not longer than 5 min. From the analysis of such emf measurements, emf values are found to increase linearly with the logarithm of the aluminum concentration. The possibility of the present method has been ascertained in Zn-Al baths.抄録全体を表示PDF形式でダウンロード (595K) -
西川 幸男, 吉田 善一, 植杉 雄二, 水口 信一1994 年 58 巻 8 号 p. 936-943
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーWe have studied the changes in the mass and surface structure of metal targets irradiated by the KrF excimer laser beam to classify the characteristics of laser ablation. The ablation energy was estimated from the mass loss and the change in temperature of targets. Changes in the structure of targets were investigated by a scanning electron microscope, an optical microscope, X-ray diffraction and Auger electron spectroscopy. ICP spectroscopy was also carried out to analyze the chemical composition of films deposited by laser ablation technique. The main results obtained are as follows.
The decrease in mass of targets is proportional to the number of laser shots and laser fluence. The average energy of 100∼180 eV per atom is required to ablate atomic particles. Belt shaped morphology of the targets becomes prominent as the number of laser shots increases. The resolidified layer is too thin to be observed by an optical microscope. The cold-worked and subsequently laser-ablated targets show the same diffraction pattern as the targets after solution treatment, which suggests that a heat-affected zone with a thickness of 9 μm in this experiment exists in the targets irradiated by the KrF excimer laser beam. Any preferential vaporization of component atoms in the target does not occur during laser ablation and thereby the difference in chemical composition between the target and the deposited film is in the range of a few percent. In this respect, laser ablation is quite different from vapor deposition.抄録全体を表示PDF形式でダウンロード (1104K) -
小柏 俊典, 井上 明久1994 年 58 巻 8 号 p. 944-951
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーA new solder bump formation method using a wire bonding machine, which was named as a solder bumping method, was developed by the use of a rapidly solidified 97.9Pb-2Sn-0.05Sb-0.05Cu wire. The most important function of the wire for the bump formation is fracturing at a constant site which enables the formation of balls with a constant size. In order to evaluate the fracture site of the wire, the ratio of the tensile proportional limit (σp) in the as-rolled state to 75-97% reductions in area to the ultimate tensile strength in the annealed state for 60 s at 571 K was investigated for the cast alloys obtained at different cooling rates. The rapid solidification and subsequent cold rolling processes cause the increase in σp(as-rolled), resulting in the increase in the ratio of σp(as-rolled)⁄σp(annealed). The addition of 0.05%Cu was necessary to keep high values of σp(as-drawn)⁄σp(annealed) exceeding 1.0. The scatterings of the shape and size of the bump after reflowing treatment for 60 s at 623 K were small enough to be put the solder bump material and the bump formation process into practical application.抄録全体を表示PDF形式でダウンロード (1707K) -
小柏 俊典, 村上 義弘, 井上 明久1994 年 58 巻 8 号 p. 952-958
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーA new 97.9Pb-2Sn-0.05Sb-0.05Cu (mass%) solder alloy for ultra-fine pitch bonding in a flip-chip assembly has been developed based on the results obtained by the following two different testing methods; (1) estimation of the number of cycles up to failure from static mechanical properties of the bulk alloy, and (2) thermal fatigue test using a flip-chip solder joint. The composition of the quaternary solder alloy was essential for the suppression of embrittlement of the bump resulting from the solution of Au to the soldered bump. The increment in the electrical resistivity for the 97.9Pb-2Sn-0.05Sb-0.05Cu bump subjected to the thermal fatigue test at temperatures between 218 and 423 K decreases to about one-third in comparison with that for a 98Pb-2Sn alloy bump, and the propagation site of crack leading to final failure also changes from the interface between the bump and the substrate to the inner area of the soldered bump. The main reason for the improvement of the thermal fatigue life time for the newly developed Pb-Sn-Sb-Cu alloy bump is presumably because the addition of 0.05 mass%Sb causes the change in the precipitation morphology of AuSn and AuSn2 compounds along the grain boundary from the continuous to dispersed state which enables the slip deformation across the grain boundary.抄録全体を表示PDF形式でダウンロード (1472K) -
駒井 正雄, 山崎 裕司, 小崎 信也, 高木 研一1994 年 58 巻 8 号 p. 959-965
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーEffects of alloying elements on the mechanical properties and boride crystal structure of Mo2NiB2 base hard alloys were studied using the alloys whose compositions were Ni-6 mass%B-58.6 mass%Mo-(0-20)mass%Cr and Ni-6 mass%B-58.6 mass%Mo-10 mass%X (X: V, Fe, Co, Ti, Mn, Zr, Nb and W). The alloys consist of a Mo2NiB2 type ternary boride as a hard phase and a nickel base binder alloyed with Mo and other elements, both of which are formed by reaction boronizing sintering.
The transverse-rupture strength (TRS) of the Cr containing alloys depended strongly on the microstructure, which varied significantly with Cr content. The maximum TRS of 2.3 GPa and a hardness of HRA87 were obtained at 10 mass%Cr content. A crystal structural change from the orthorhombic M3B2 (M: Metal) to the tetragonal M3B2 was observed with increasing Cr content. The highest TRS value at 10 mass%Cr was attributed to the formation of fine M3B2 particles with a tetragonal structure.
In the eight additional elements, vanadium showed the same effects as chromium on the mechanical properties associated with the crystal structural change of M3B2 from the orthorhombic to the tetragonal. Additions of the other alloying elements did not lead to the crystal structural change of M3B2 and the improvement of the mechanical properties of the Mo2NiB2 base hard alloys.
The Rietveld analysis method successfully revealed the atomic configurations as well as the lattice parameters of the unit cells of the orthorhombic M3B2 at non-Cr and the tetragonal M3B2 at 10 mass%Cr.抄録全体を表示PDF形式でダウンロード (1924K) -
沖 幸男, 合田 進1994 年 58 巻 8 号 p. 966-972
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーPure aluminum of 99.9% purity was sprayed onto the austenitic stainless steel substrate containing 18% Cr and 8% Ni by the wire arc spraying method. The spray-coated specimens were heat treated at temperatures from 923 to 1223 K for 0.9 to 14.4 ks in the atmosphere. The alloy phases of spray coated and diffusion treated specimens were characterized by the optical micrograph and Vickers hardness of each layer. The identification of each phase by X-ray diffractometory and electron prove microanalysis were also carried out.
The results obtained were as follows:
(1) Diffusions of aluminum into the substrate and of iron, nickel and chromiun from the substrate occurred. Intermetallic compounds of those elements were formed and the total thickness of the alloy phases formed by the heat treatment at 1023 K for 3.6 ks was about 120 μm.
(2) The compounds formed in the alloy layer consisted mainly of Al-Fe binaly phases, that is AlFe3, ζ(Al2Fe), η(Al5Fe2) and θ(Al13Fe4).
(3) The morphorogy of the interface between the alloy layer and the substrate was rather uniform in comparison with that formed in the Al-sprayed plain carbon steels. This may be attributed to the coexistance of the φ(Al10Fe3Ni) phase with the η(Al5Fe2) phase in the same layer.抄録全体を表示PDF形式でダウンロード (862K) -
森本 啓之, 岩村 宏, 安倍 睦, 芦田 喜郎1994 年 58 巻 8 号 p. 973-979
発行日: 1994年
公開日: 2008/04/04
ジャーナル フリーThe effect of dispersed particle size on the tensile properties of particulate-reinforced aluminum composites and the mechanism of strengthening were studied. The aluminum composites reinforced with 0.3, 1 or 28 μm SiC particles and the aluminum without particles for comparison were fabricated with a powder metallurgical process. The volume fraction of particles was fixed at 20%. The SiC particles were dispersed nearly uniformly in all samples. The tensile properties were evaluated and the microstructures were observed using transmission electron microscopy. Yield stress (0.02% proof stress), 0.2% proof stress and ultimate tensile strength increased with decreasing particle size. Aluminum grain size was refined to 0.4∼1.8μm due to dispersion of particles. Refinement of particles resulted in reduction in the interparticle spacing, which refined the aluminum grain size markedly. From this result and application of the Hall-Petch relation, it was demonstrated that the refinement of the aluminum grain size is the major reason for the great increase in yield stress of the finer particle composites. In spite of proceeding of deformation, the dislocation structure near the SiC particles did not change, whereas a number of dislocations were observed in aluminum grains apart from the SiC particles, which indicates that the deformation in composites is not uniform. This suggests that the deformation of aluminum between the particles is restricted in fine particle reinforced composites, and consequently, the uniformity of deformation in such composites is improved, resulting in the increase in work hardening, as observed experimentally.抄録全体を表示PDF形式でダウンロード (1409K) -
山中 淳二, 入戸野 修1994 年 58 巻 8 号 p. 980-981
発行日: 1994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 (136K) -
渡邉 淳, 須佐 匡裕, 永田 和宏1994 年 58 巻 8 号 p. 982-983
発行日: 1994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 (189K)
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