巻号一覧
40 巻, 8 号
選択された号の論文の17件中1～17を表示しています
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森岡 恭昭1993 年 40 巻 8 号 p. 755-762
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーPowder metallurgy products cover a wide range of applications and are used in the automotive, electrical, business machine, agricultural machine, sewing machine and other industries.
First, the powder metallurgy market, especially recent shipments of iron powder, copper powder, low alloy steel powder, and stainless steel powder, and production amounts of various powder metallurgy products in Japan, are introduced.
Second, the history of development in FM parts, new types of raw powder, e.g. high compressibility iron powder, good campactibility iron powder, segregation-free iron powder, high strength low alloy steel powder, rapidly solidified aluminum alloy powder, and fine alloy powder, and recently developed FM parts manufacturing techniques, are outlined.
Although the Japanese powder metallurgy industry felt the effects of economical recession in the early 90s, the outlook for the future is very positive, and the FM industry is expected to show renewed growth, because the applications of FM parts range over many industries, and various types of new raw powders, FM materials and FM manufacturig techniques are now being developed.抄録全体を表示PDF形式でダウンロード (519K) -
山本 勉1993 年 40 巻 8 号 p. 763-769
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーIn the field of cutting and plastic working, the role of carbide tools has been steadily increasing due to the request of processing with high efficiency and tolerance as well as the application of high-grade work materials. Carbide tool materials consisting of cemented carbides, coated carbides, cermets, ceramics, polycrystalline diamond and cBN are applied in various fields that they can fully display their own properties.
Recently, the carbide tool materials have been improved to show a longer or more consistent tool life for high-efficient processing. In this paper, therefore, the structural properties of the carbide tool materials are mainly described.抄録全体を表示PDF形式でダウンロード (6862K) -
志賀 信哉, 銭本 陽一, 藤本 京太, 梅本 実, 岡根 功1993 年 40 巻 8 号 p. 770-773
発行日: 1993/08/15
公開日: 2009/12/04
ジャーナル フリーMechanical alloyed mixtures of elemental Fe and Si powders with compositions FexSi100-x (10≤X≤50) have been characterized in the as-milled condition, as well as after heat treatments. Ball-milling in an argon atmosphere first induces alloying of the elements, followed by the formation of FeSi(ε) compound in the mixture of Fe50Si50, and FeSi2(β) compound in the mixture of Fe30Si70. Upon heating a Fe30Si70 mixture previously milled for 720ks, transformation to an almost single phase FeSi2 occurs, with the exothermic reaction at around 723K. The MA powders milled for 720ks, heated to temperatures between 1173K and 1273K and air cooled, exhibited the phases. expected from the Fe-Si phase diagram. A substantial enhancement of the (Fe2Si5(α) + ε) to β transition was observed in the MA powders of Fe30S70 composition in which the β phase formed from (α+ε) during furnace cooling from 1273K. This enhancement of the (α+ε) to β transition is considered to be due to the enhanced diffusion resulting from the refinement of grain sizes of the α and ε phases after MA.抄録全体を表示PDF形式でダウンロード (1478K) -
池田 保之, 高木 節雄, 鎌田 政智, 徳永 洋一1993 年 40 巻 8 号 p. 774-779
発行日: 1993/08/15
公開日: 2009/12/04
ジャーナル フリーThe sintering behavior of TI-4mass%Cr alloy compact prepared by the technique of elemental powder mixing was investigated by means of EPMA analysis and optical microscopy. Mechanical properties of sintered compacts, in which the microstructure of (α+β) two phases was controlled by varying the cooling rate from sintering temperature, were also examined In relation to the fracture behavior. Addition of 4mass%Cr gives no effect on compactibility and sintering densification of titanium powder. However, the diffusion of chromium Into titanium matrix is greatly dependent on temperature, so that the sintering above 1373K is required for the 3.6ks sintering in order to obtain homogenlous materials in the chemical composition. In the case of 1473K-3.6ks sintering, the density of Ti-4mass%Cr alloy compacts increases to more than 95% in relative density in addition to the homogeneity of chemical composition. The structure of compacts is of β(bcc) phase at 1473K, but a platelet a(hcp) phase precipitates during cooling from the sintering temperature. When the cooling rate after sintering is over 1K/s, a fine mixed structure of α and β is obtained at room temperature, and this results in excellent mechanical properties. When the cooling rate is not so fast, the a phase grows large. Specimens with coarse structure of α and β undergo a quasi-cleavage fracture, In which cracks propagate in the β phase along a plates and then connect retained pores. Such a fracture mode affects harmfully to mechanical properties, especially to bending strength.抄録全体を表示PDF形式でダウンロード (5909K) -
樋口 月光, 山本 康一, 坂本 雅昭1993 年 40 巻 8 号 p. 780-783
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーAs the recent bearings have been applied under higher load and insufficient lubrication, bearing materials should be further improved to have better anti-wear property.
In order to obtain bearing materials of better anti-wear property under such conditions as edged loading and boundary lubrication, we have studied sinterd composite alloys having the steel back by adding Ni-B compound, as the wear resistant particle, to the relatively soft Cu-3.5wt%Sn-23wt%Pb alloy base. Mechanical properties and wear resistance were investigated for these composite alloys. Test results showed that hardness and tensile strength increased gradually by adding the amount of Ni-B hard compound, and that the anti-wear property of composite alloys with 3-8wt% of Ni-B addition was four times better than that of the conventional Cu-3.5wt%Sn-23wt%Pb alloy.抄録全体を表示PDF形式でダウンロード (2926K) -
山本 良治, 松本 明英, 本川 惺, 志垣 憲良1993 年 40 巻 8 号 p. 784-788
発行日: 1993/08/15
公開日: 2009/12/04
ジャーナル フリーThe determing factor of tungsten oxide particle size during thermal decomposition of monoclinic ammonium paratungstate (APT) has been studied. APT was decomposed by thermobalance in nitrogen, oxygen, air and mixture of ammonia and nitrogen atmosphere. Formation mechanism of ultrafine tungsten oxide particle was investigated using X-ray diffraction analysis, scanning electron microscopy and specific surface area measurement. The relationship of particle size between hexagonal ammonium tungsten bronze (ATB) and tungsten oxide was discussed. Formation of ATB was controlled by parameters such as heating rate, sample mass and kind of atomosphere. Particle size of tungsten oxide was affected with amount of ATB formed in the intermediate, that is, particle size was very fine when ATB was formed in large quantities. Ultarfine individual particle of tungsten oxide was formed by a decomposing reaction from ATB to W03 or WO2.9, and grain growth of its particle took place at temperatures above 873 K.抄録全体を表示PDF形式でダウンロード (4078K) -
Ken Hirota, Osamu Yamaguchi, Suguru Inamura, Hiroki Miyamoto1993 年 40 巻 8 号 p. 789-793
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーHexagonal YAIO3 crystallizes at low temperatures from an amorphous material prepared by the simultaneous hydrolysis of yttrium and aluminum alkoxides. It transforms to the cubic phase with a garnet structure as an intermediate product at elevated temperatures. The formation process of YAlO3 is described. Solid solutions of hexagonal YAlO3 crystallize between 50 and 62.5 mol% Al2O3. Yttrium aluminum garnet, Y3Al5O12 (YAG), is formed by the transformation of the hexagonal YAlO3 solid solution.抄録全体を表示PDF形式でダウンロード (284K) -
泥しょう調製条件の検討佐野 三郎, 水田 博之, 前田 雅喜, 寺西 久広, 小田 喜一, 芝崎 靖雄1993 年 40 巻 8 号 p. 794-799
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーSlip casting of low soda alumina powder was studied to fabricate alumina engineering ceramic parts with a complicated shape. As the powder characteristics, the isoelectric point of low soda alumina powder was determined from zeta-potential measurement to be pH=9.1. The preparation conditions of well-dispersed slurries were found for the low soda alumina by using an organic polymer deflocculant (polycarboxylic ammonium) and a binder (D-sorbitol). An optimum amount of added deflocculant was 0.15wt%, because at this amount the slurry showed large negative zeta-potential and the lowest apparent viscosity. Green bodies were prepared from the slurry by vacuum filtration with a porous resin mold. High-density (3.92-3.94g/cm3) sintered bodies were obtained by sintering at 1650°C for 2h in air.抄録全体を表示PDF形式でダウンロード (1752K) -
真空・加圧鋳込成形と焼結体の機械的特性佐野 三郎, 水田 博之, 前田 雅喜, 寺西 久広, 小田 喜一, 芝崎 靖雄1993 年 40 巻 8 号 p. 800-804
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーVacuum-pressure assisted slip casting of low soda alumina powder was studied to fabricate alumina engineering ceramic parts with a complicated shape. A well-dispersed low soda alumina slurry (82wt% solids) was prepared by adding 0.15wt% polymer deflocculant (polycarboxylic ammonium), 0.3wt% binder (D-solbitol) and O.1wt% defoamer (ethylene glycol). The consolidation kinetics of the slurry using the vacuum-pressure assisted slip casting system with a porous polymer resin mold and the mechanical properties of the sintered body were investigated. The rate of filter cake buildup (k) was experimentally determined to be 1.26x10-13P[m2/s]. The sintered body of low soda alumina showed a high density of 3.94g/cm3 and a high flexural strength of about 500MPa. It was found that the vacuum-pressure assisted slip casing was a useful forming method of low soda alumina.抄録全体を表示PDF形式でダウンロード (319K) -
高橋 俊行, 勝村 祐次, 鈴木 寿1993 年 40 巻 8 号 p. 805-808
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーThe Al2O3 compact with extremely fine grain size (about 0.8gm) was prepared by sintering in vacuum at 1523K and then HIP-treatment in argon at 1473K. The structure and mechanical properties of the white ceramics as above were mainly studied, comparing with those of conventional white ceramics. The results obtained, for instance, were as follows. The room temperature transverserupture strength of the fine grained ceramics reached the value of about 1.3 GPa, being in good contrast to that of about 0.7-0.9GPa of conventional one (according to JIS R 1601, 1981). It was noted that the value of creep strain of fine grained one surprisingly increased, in comparison with conventional one.抄録全体を表示PDF形式でダウンロード (3928K) -
斉藤 諭, 中野 敦之, 野村 武史1993 年 40 巻 8 号 p. 809-814
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーEffect of composition, residual stress and small amount of additives on the electromagnetic properties of low temperature sintered NiCuZn ferrite has been studied with reference to the loss analysis and the microstructure. It is shown that the total core loss has strong composition dependency and it is very important to control the composition to achieve low core loss for power use. The higher the residual stress, the higher the total loss, because of increase in hysteresis loss. Most effective additive is V2O5.抄録全体を表示PDF形式でダウンロード (3912K) -
小崎 信也, 山崎 裕司, 駒井 正雄, 高木 研一1993 年 40 巻 8 号 p. 815-819
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーBonding properties of Mo2NiB2 base hard alloys with various steels were studied by using the model alloys whose compositions were Ni-4mass%B-42.6mass%Mo-17.5mass%Cr. The new hard alloys consist of a Mo2NiB2 type ternary boride as a hard phase and a nickel base binder alloyed with Cr, Mo and other elements, both of which are formed by reaction boronizing sintering.
The hard alloys showed the shear strength of over 400MPa bonded with JIS S45C, SKD61, SCM 440, SUS42OJ2 at 1533K and that of over 700MPa with JIS SUS316L and SUS304 at 1503K. Surface roughness of the steels affected shear strength of the hard alloys bonded with JIS S45C, SKD 61, SCM440. Bonding time of 300sec was enough for high shear strength of the hard alloys bonded with various steels except JIS SKD61. The residual compressive stress in the hard alloys and residual tensile stress in the steels were measured by an X-ray diffraction stress analyzer. The results were attributed to the difference in the thermal expansion coefficient between the hard alloys and various steels.抄録全体を表示PDF形式でダウンロード (3603K) -
木下 聡, 植木 光生, 鈴木 寿1993 年 40 巻 8 号 p. 820-822
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーIt is known that titanium carbide based cermet containing nitrogen(N) in the form of TA or Ti (C, N) shows excellent creep resistance compared with that of N-free cermet. It is expected that when N-free cermet is nitrified during raising temperature and subsequently sintered, it also shows excellent creep resistance. The object of this study is to clarify the above subject experimentally. It was made clear that the creep characteristics of N-free cermet sintered after nitrification under an adequate condition were superior, as expected, though the N content of nitrified cermet was lower than the value of TiC-TiN-Mo2C-Ni cermet.抄録全体を表示PDF形式でダウンロード (149K) -
冨耒 靖, 高野 英明, 坂東 尚周1993 年 40 巻 8 号 p. 823-826
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーThe preparation process and magnetic properties of ε'-Fe2.2C fine particles are reported. Acicular a -FeO(OH) particles were selected as starting materials for ε'-Fe2.2C particles. α-FeO(OH) particles were heated at 260°C for 3h in air to be transformed into α-Fe2O3. The α-Fe2O3 particles had the acicular shape similar to α-FeO(OH) particle shape and contained numerous micropores with a few nanometers in diameter. α-Fe particles prepared by heating α-Fe2O3 at 300°C for 4h in H2 flow were granular and 40-60 nm in diameter. The α-Fe particles were carburized in the mixing gas flow of CO and H2 in the ratio of equal volume. ε'-Fe2.2C phase was obtained at the reaction temperatures from 200°C to 240°C. Synthesized particles were identified as a single phase ε'-Fe2.2C by XRD pattern and had the size and the shape similar to α-Fe particles. The saturation magnetization of ε'-Fe2.2C fine particles was 117 emu/g, while the coercive force was 1042 Oe.抄録全体を表示PDF形式でダウンロード (2957K) -
小熊 規泰, 杉田 忠彰, 西 誠1993 年 40 巻 8 号 p. 827-832
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーIn this paper, the sensing conditions for sensitive acoustic emission (AE) signals are mentioned and AE source position method for improvement accuracy is discussed, and the detection of crack failure of silicon nitride ceramic bearings in rolling contact is carried out by this method.
AE sensor sensitivity is estimated by the effect of mounting conditions of AE sensor which are holding sensor pressure and couplant between sensor and specimen. As a result, sensitive AE signal is obtained when the pressure should be greater than 1.2MPa using oil or grease as the couplant. It is possible to determine the position of AE source accurately by mesuring the arrival time difference of the second peak point of each wave between sensors.
In the experimental result of the rolling contact bearings, error of the surface crack position is 1.56mm. This value is a satisfactory accuracy.抄録全体を表示PDF形式でダウンロード (1748K) -
安斎 正博, 大滝 久規, 綾部 由紀, 高橋 清造, 川島 悦哉, 中川 威雄1993 年 40 巻 8 号 p. 833-836
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーMagnetic abrasive finishing is very interesting finishing method, but this has a weak point of low grindability. Electrolytic-magnetic abrasive finishing is thought as one of the potential method to improve this weak point. This study aims at developing the new abrasive for electrolyticmagnetic finishing and investigating the grindability of this abrasive. The ferrite-Al2O3 abrasive which was made by sintering has high grindability in comparison with sintered ferrite abrasives or soft ferrite raw powders. Ferrite-base abrasives will become a very useful in the electrolytic-magnetic abrasive finishing.抄録全体を表示PDF形式でダウンロード (2614K) -
星野 孝二, 河野 通, 森川 正樹1993 年 40 巻 8 号 p. 837-840
発行日: 1993/08/15
公開日: 2009/05/22
ジャーナル フリーPrecious Metals Clay which is a mixture of a precious metal powder and organic binders was doveloped. Two types clays were made by the binders of the different compositions. One resembled a paper clay and others resembled a chewing gum. Sintering process was investigated to make a gold of 18 carat from the Precious Metals Clay contained a mixed powder of 75%Au-12.5%Ag-12.5%Cu. The results showed that the two steps sintering process involving oxidation and reduction was suitable to sinter it. The sintered precious metals had enough strength to use as an ornament or a jewelery, although the mechanical properties were lower than the cast materials. Hollow beads could be made from the Precious Metals Clay using the Core Clay which was made of cellulose.抄録全体を表示PDF形式でダウンロード (6522K)
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