巻号一覧
42 巻, 9 号
選択された号の論文の22件中1～22を表示しています
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鰐部 吉基1995 年 42 巻 9 号 p. 974
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (82K) -
高井 伝栄, 猪飼 善弘1995 年 42 巻 9 号 p. 975-981
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーKOBE STEEL, LTD(KSL) has been produced the steel powder for P/M structual part. Due to an increase of demand of powder and strict requirement of its quality, KSL constructed a new powder plant.
The new powder plant succeeded to increase its productivity by three times with fifty percent reduction of variation of properties using a state-of-art automated and consecutive line. The new plant improved powder quality, cost competitiveness and working environment which meet an original plan.抄録全体を表示PDF形式でダウンロード (389K) -
宗倉 雅章1995 年 42 巻 9 号 p. 982-985
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーSintered P/M parts have been widely used in many automobiles, home-electric machines and the other industrial machine applications because of their good productivity for the parts with complicated shape and high precision, and their flexibility for material design with low cost. The production amount have been increased year by year. Especially, in the field of the mechanical parts, it showed a double increase in the past ten years. However, the increase of P/M production in Japan have shown a drop because of the economic situation. In 1993, the recoed showed a minus of the increase. Under such a series condition, many new technology were applied into P/M field, in order to expand the use of sintered parts. Here, we give a review on these topics.抄録全体を表示PDF形式でダウンロード (1328K) -
寺下 敬次郎, 西村 清彦, 宮南 啓1995 年 42 巻 9 号 p. 986-991
発行日: 1995/09/15
公開日: 2009/12/04
ジャーナル フリーIn this study, composite particles were prepared by dispersing fine powder particles (mean diameter 0.2μm) on core particles (mean diameter 12μm) by dry coating. This paper shows a new method of quantitatively evaluating the state of fine powder particle dispersion on the surface of each core particle by image analysis. The findings are summarized as follows:
The state of fine powder particle dispersion on the surface of each core particle was successfully evaluated by degree of dispersion.
Evaluation of the dispersion state by degree of dispersion was verified by the coefficient of variance for the relative intensity of the characteristic X-ray from fine powder particles and powder layer brightness on each composite particle.
Image analysis makes it possible to obtain the diameter of each fine powder particle dispersed on the surface of a composite particle. The process in which fine powder particles are dispersed in the form of primary particles was thus clarified. Optimum operation time for obtaining composite particles having fine powder particles dispersed thereon was found on the degree of dispersion and the measurement of the diameters of fine powder particles.抄録全体を表示PDF形式でダウンロード (1782K) -
Takashi Itoh, Yoshimoto Wanibe, Koji Kuroda1995 年 42 巻 9 号 p. 992-997
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーThis is a fundamental approach to the quantitative characterization of powder/short fiber mixtures. Attention has been paid to the packing structures of powder/short fiber mixtures because of a main factor in successive consolidation processes and products. Numerous types of metallic powders and short fibers in commercial market are used for this study. Packing densities are measured at various blending ratios for ten combination sets of the powders and the fibers. The powders have been characterized with a dispersion diagram of particle sizes and shapes which had been reported in the previous work. The short fibers can be also morphologically characterized in a similar way. The measured packing densities can be related to the blending ratio and the morphologically characterized quantities of the powders and the short fibers.抄録全体を表示PDF形式でダウンロード (385K) -
今村 正人, 兼子 正生, 柳沢 章, 中川 威雄1995 年 42 巻 9 号 p. 998-1003
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーIt is extremely difficult to sinter aluminum due the stable alumina film which exists on its surface. It was found that aluminum fibers can be bonded easily by freezing of melted polyethylene at a low temperature in the heat-treatment of polyethylene-laminated aluminum fibers. It was also clarified that strength and porosity can be controlled arbitrarily by adjusting the amount of polyethylene which contributes to binding by adding pure aluminum.抄録全体を表示PDF形式でダウンロード (3439K) -
兼子 正生, 柳沢 章, 今村 正人, 中川 威雄1995 年 42 巻 9 号 p. 1004-1008
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーIn the fabrication of metal powder or fiber products without the sintering. process, a different material which is melted at a comparatively low temperature is often used.as the binder instead of the matrix material. In this case, the characteristics of the product differ from those of the matrix material because they are controlled by the binder used. Moreover, aluminum has the disadvantage of being difficult to sinter due its oxidation film. In this research, the fabrication of aluminum alloy fiber products was therefore attempted with the use of fibers obtained by shaving brazed aluminum sheet material (which is Al-Mn alloy whose both sides are cladded with Al-Si eutectic alloy). In this process, it was confirmed that Al-Si eutectic alloy which is molten at a low temperature is used as binder, and porous aluminum sheet with porosity 40-60% and tensile strength 10-17MPa can be fabricated.抄録全体を表示PDF形式でダウンロード (2657K) -
高橋 清造, 中川 威雄1995 年 42 巻 9 号 p. 1009-1014
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーA cup-shaped compact with a wall thickness of 3 mm and wall height of 20 mm was formed from iron powder admixed with zinc stearate and micro wax powder or solid paraffin wax. The green compact obtained, compared with that formed by adding only zinc stearate, showed little internal density difference, and consequently had high density. The micro wax and powder-coated paraffin wax are believed to reduce the friction between the powder and raise the densty of the cup wall when added. This indicates that the powder flows from the bottom of the cup to the cup wall in the compaction process. The radial crushing strength of the cup wall admixing with 0.5 mass% zinc stearate and 1 mass% paraffin wax amounted to 28 MPa.抄録全体を表示PDF形式でダウンロード (1530K) -
大迫 敏行1995 年 42 巻 9 号 p. 1015-1018
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーThe Random Resistor Network Approach is applied to a modeling of the relative viscosity of disperse systems. A suspension that solid particles are dispersed in a liquid is represented by occupied or empty sites of cubic lattice. The resistivity of the heterogeneous system is equivalent to the viscosity of suspension according to the excitation-response theory. Monte Carlo simulation of zero-shear viscosity was conducted for the varied solids loading and solid/liquid bond resistance. The calculation results exhibit a good agreement with the experimental data obtained before. Bond Resistance and bond probability of particles introduced into the model enables the modeling of the dynamic viscous behavior of suspensions.抄録全体を表示PDF形式でダウンロード (295K) -
小寺 秀俊, 北原 治倫, 島 進1995 年 42 巻 9 号 p. 1019-1026
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーA particle dynamic simulation is useful to estimate powder characteristics and to understand the particle behavior under compaction. As a model particle a circular and a spherical particle are used in calculation. However, a shape of real particle is not circular or spherical. To estimate the powder characteristics quantitatively by particle dynamic simulation, it is of great importance that the particle is modeled as non-circular and spherical shape. In this study, we modeled the ferromagnetic ellipsoidal particle using four arcs. We show how to define the particle using arcs and how the ellipsoidal particle is magnetized in the magnetic field. We simulated how the easy axis of the particle is aligned under isostatic compaction. Thus we make clear the behavior of noncircular particle under compaction in the magnetic field.抄録全体を表示PDF形式でダウンロード (4732K) -
Al-Si合金加圧成形体に及ぼす機械的撹拌の影響師岡 利政, 湯浅 栄二, 河村 忠二, 宮原 輝明, 吉弘 憲司1995 年 42 巻 9 号 p. 1027-1031
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーExperimental study was carried out on semi-solid diecasting process using mixture of elemental aluminum and silicon powders. The mixture of powders was heated to the semi-solid state temperature of 30% volume fraction of solid phase and then it was mechanically stirred. After stirring, it was forced into preheated metal die-cavity. The results are as follows.
The fludity of the stirred slurry and the surface condition of products are improved by the stirring. In the optical micrografic structure of the products, α phase is spheroidized and eutictic structure is refined by the stirring of srurry. Tensile strength, elongation and hardness of the products prepared from the stirred slurry are higher than those of the products prepared from unstirred slurry.抄録全体を表示PDF形式でダウンロード (5361K) -
大橋 善久, 荒川 尚1995 年 42 巻 9 号 p. 1032-1036
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーMethod of density measurement using an X-ray CT scanner was investigated particularly forpowder compacts. Since X-ray absorption characteristics are different in various materials, densities are able to be known from CT values, which are functions of X-ray absorption coefficients of the materials. High energy X-rays around 200-300keV realized high correlation between the CT values and material densities. The values, however, were influenced by the size of samples and varied within the same sample even that is uniform in density. These phenomena were caused by beam hardening characteristics in white X-ray of the CT scanner and by the problem of accuracy in CT computation. In spite of the condition, very high correlation was obtained between densities and CT values in aluminum powder compacts. A density distribution in the compact, which was converted from the measured CT value distribution, exhibited a typical distribution in powder compact. Because of the beam hardening and the problem in computation accuracy, CT values in a wrought aluminum sample distributed within about 2.5% of the mean density. Almost the same error should be considered in CT value distributions in powder compacts.抄録全体を表示PDF形式でダウンロード (376K) -
林 卓, 伊藤 岳英, 安島 香緒里, 佐々木 〓一1995 年 42 巻 9 号 p. 1037-1041
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーChemical processing of Nb2O5-added BaTiO3 composites was investigated with the surface modification through the hydrolysis of niobium alkoxide on the surface of BaTiO3 particles.
BaTiO3 particles were coated with niobium hydroxide particles formed by preferential hydrolysis of niobium pentaethoxide on the surfaces of BaTiO3 particles, which can lead to the preparation of highly homogeneous composite particles of Nb2O5BaTiO3.
It was clarified from the BET measurement, the SEM&TEM observation and Zeta-potential measurment that original BaTi03 particles were homogeneously coated with niobium hydroxide particles.
Iwt%Nb2O5-added BaTiO3 bodies sintered at 1250-1300°C exhibited a flattened dielectric temperature dependence (dielectric constants of 2200 to 2400) with lower loss(tan δ<1.0%) in the temperature range of -30 to 80°C, indicating a relaxor characteristics. The microstructure of Nb2O5-added BaTiO3 sintered bodies consisted of grains of several μ m which are much smaller than ones of non-added BaTiO3 sintered bodies, suggesting that the grain growth of BaTiO3 was inhibited by niobium existing at the grain boundaries.抄録全体を表示PDF形式でダウンロード (3067K) -
山崎 裕司, 野中 和則, 岡田 光治, 高木 研一1995 年 42 巻 9 号 p. 1042-1046
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーSintering of a Ni-6 mass%B-58.6 mass%Mo-10 mass%Cr alloy was attempted to differentiate the effects of Cr source as an addition to the alloy by using CrB powder and Cr powder respectively. The sintered alloy using CrB powder showed superior mechanical properties to the alloy using Cr powder. An orthorhombic complex boride was formed prior to formation of a tetragonal complex boride in the alloy regardless of Cr source. The alloy using CrB powder exhibited a faster crystal structural change from orthorhombic to tetragonal with the increasing temperature than the alloy using Cr powder.抄録全体を表示PDF形式でダウンロード (2545K) -
Toshihiko Nishida, Naoki Maeda, Masahiro Kihara, Tomohiko Ogata1995 年 42 巻 9 号 p. 1047-1051
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーA fracture mechanics specimen shaped as a single-edge double-notched beam (SEDNB), was specially designed for evaluating the fracture properties of brittle ceramic materials. The notch-tip was sharpened to a radius <10μm in order to reduce the amount of elastic energy stored at its root prior to crack extension. Furthermore, a crack stabilizer, designed for the bending geometry, was employed. The use of this special stabilizer as well as a new machining technique developed for introducing the sharp notches made it possible the detectability of near-tip R-curve behavior, and to discern it from long-crack R-curve behavior. As an application of this technique, the R-curve behavior of Al2O3/ZrO2 (2.5Y-TZP) composites has been evaluated and the micromechanism responsible for such a behavior theoretically discussed.抄録全体を表示PDF形式でダウンロード (4162K) -
京極 秀樹, 小松 眞一郎, 土取 功, 戸田 拓夫1995 年 42 巻 9 号 p. 1052-1056
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーThe microstructures and tensile properties of sintered Ti-4%Fe alloy compacts made by injection moldings were investigated. Specimens were made of Ti and carbonyl Fe powders with average diameters of 16 and 5 micrometer, respectively. Two kinds of binder systems containing 17.5% and 50% wax were used. The compacts were debound at 523K and 593K in air and then sintered at 1523K in vacua. The carbon content of sintered compacts decreased to 0.2% by using the binder system containing lower wax. Therefore, the microstructure of sintered compacts obtained by using the binder did not have TiC precipitates. The density of the sintered compacts increased by using finer Ti powder. The tensile strength of the sintered compacts was 230MPa.抄録全体を表示PDF形式でダウンロード (4715K) -
土屋 信次郎, 土屋 一彦, 福田 雅秀, 宮谷 和雄1995 年 42 巻 9 号 p. 1059-1062
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーA quantitative analysis of the tetragonal phase in Mg-PSZ by a standard X-ray powder diffraction method was carried out using the diffraction intensities with the Miller indices (311). The volume fraction of the tetragonal phase is shown to be given by
Vt=2.92/(1+0.991 X), where X={It(311)+Ic(311)}/It(113) which involves the diffraction intensities It and Ic of the corresponding tetragonal and cubic phases. The standard error of this method was estimated to be 4.5%. The present result is applicable to evaluate the tetragonal phase and the cubic phase in Mg-PSZ which contains the monoclinic phase less than 37%.抄録全体を表示PDF形式でダウンロード (212K) -
大橋 照男, 汲田 昌弘, 田中 靖久1995 年 42 巻 9 号 p. 1063-1067
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーA high energy type ball-milling machine for mechanical grinding (MG) was used to examine its effectiveness of redistributing the insoluble slolute of Pb in the Cu-Sn-Pb alloy powders and the structures of these MG powders were also discussed. The sufficiently deformed and pulverized powders were attained after a milling time of about 20hr, and composed substantially from the crystallites of Cu and Pb the diameter of which was about 10nm. In some parts of these powders, an amorphous-like structure could be observed by TEM but not by XRD. The formation of stacking faults during milling was confirmed in Cu by pesk shifts of (111)Cu and(200)Cu reflections of XRD. The result of DSC measurements carried out on the MG powders showed the stored energy in the MG powders was estimated to be about 3 kJ/mol irrespective of Sn content and less than one-third of the mixing free energy of the supercooled liquid Cu-Pb alloy.抄録全体を表示PDF形式でダウンロード (1452K) -
加藤 清隆, 松本 章宏, 野崎 佳彦, 家城 悌1995 年 42 巻 9 号 p. 1068-1072
発行日: 1995/09/15
公開日: 2009/12/04
ジャーナル フリーSintered binary Ti-Al compacts with various Ti/Al ratios prepared by metal injection molding process were investigated. Powder materials used for this study were pre-alloyed TiAl powders (average particle size:10μm), which compositions were Ti55Al45, Ti52Al48, Ti50Al50, Ti48Al52 and Ti45Al55. The green compacts were debound in air or vacuum(102Pa order). Subsequently, they were sintered at 1648K for 7.2ks in vacuum(10-2Pa).
Sintered densities of the compacts after air debinding were lower than that of the compacts after vacuum debinding for all compositions. Relative sintered densities of Ti55Al45 to Ti48Al52 compacts after vacuum debinding were above 96.5%. A Ti45Al55 compact had lower density(94.5%) than the others. Microstructures of the former were composed of two phases of γ and α2. The latter showed γ-phase only. Lamellar structure was observed in the microstructures of Ti55Al45 to Ti50Al50 compacts. Tensile strength at room temperature of Ti55Al45 to Ti48Al52 compacts were in the range of approximately 350-400MPa. A Ti48Al52 compact had the highest strength in all of the TiAl compacts.抄録全体を表示PDF形式でダウンロード (3739K) -
山下 治1995 年 42 巻 9 号 p. 1073-1078
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーThe Nd-Fe-B alloy powder was kneaded at 283K with the binder of methylcellulose dissolved in water. The mixture was injected at temperature 293K in a die of 353K, which is slightly above the sol-gel transformation temperature of methylcellulose. The magnetic field of 1.35 (MA/m) was applied to produce the alignment of easy magnetization direction of alloy powder in a molded body. The molded body was dehydrated by the vacuum-drying method to suppress the oxidation of alloy powder. By heating it in H2 at 573K for 0.5H, about 80% of carbon in binder was removed, although the oxygen in binder remained unremoved. With the molded body added 2wt% methylcellulose, these treatments can allow to suppress the residual contents of oxygen and carbon in the resulted sintered Nd-Fe-B alloy within less than 9000ppm and 800ppm, respectively. The highest coercive force (iHc) and maximum energy product (BH) m ?? x for a sintered anisotropic magnet prepared by the above mentioned process are 1.10(MA/m) and 287.2(kJ/m3), respectively.抄録全体を表示PDF形式でダウンロード (339K) -
宮内 昌文, 藤田 助男, 井上 幸俊, 汐見 勝彦1995 年 42 巻 9 号 p. 1079-1082
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーRecently saddle-saddle type deflection yoke (DY) becomes the major trend for Display CRT. So, we have studied over the activity of ferrite core used in saddle-saddle type DY. The initial permeability of ferrite core used in deflection yokes is generally about 350. Though this experiment by changing the initial permeability from MnMgZn ferrite to Ni Zn ferrite, we studied the direction how to improve the accuracy of ferrite core dimension by lowering the initial permeability to be able to use in the deflection yokes.As the result, if the ferrite cores for saddle-saddle type deflection yoke have at least more than 100 value of initial permeability, the practical performance can be obtained.抄録全体を表示PDF形式でダウンロード (208K) -
古山 努, 渋江 和久, 熊谷 正樹1995 年 42 巻 9 号 p. 1083-1087
発行日: 1995/09/15
公開日: 2009/05/22
ジャーナル フリーWe report the dimensional change of powder mixture of titanium and aluminum alloy during reactive sintering in hot isostatic pressing(HIP) . The powder mixture of titanium and aluminum alloy were prepared by using powder extrusion process with various extrusion ratio. The hot pressed material showed a swelling during reactive sintering because of the pore formation. The materials with extrusion ratio over 5.4 exhibited a volumetric shrinking at the ratio of 0.96. However, these materials exhibited anisotropic dimensional change. The materials that had a extrusion ratio from 17.6 to 295 showed the expansion at the ratio of 1.1 for longitudinal direction of extruded direction and the shrinkage at the ratio of 0.93 for radial direction of extruded direction. This anisotropy is due to the fibrous structure developed by extrusion.抄録全体を表示PDF形式でダウンロード (3204K)
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