巻号一覧
43 巻, 11 号
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日高 謙介1996 年 43 巻 11 号 p. 1264
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (85K) -
村橋 紀昭, 甲元 宏明, 河野 通1996 年 43 巻 11 号 p. 1265-1272
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーHigh melting point intermetallic compounds are potential candidates for ultra-high temperature structural materials for aerospace and energy. Nb3Al has been being developed in the MITI's "high performance materials for severe environments project". This project started as an eight-years national project in 1989. Nb3Al has a high melting temperature, 2233K, and ordered A15 structure. Due to the crystal structure, this compound exhibits limited ductility and limited workability. Powder metallurgical processing, especially using the rapidly solidified powder for the starting material, must be useful for preparation of this brittle compound. For the production of the Nb3Al powder, a new gas-atomizing technique has been developed. By using the gas-atomizing pilot plant that has the pressurized plasma furnace with the melting capacity of 10kg of Nb3Al, the rapidly solidified Nb-Al powders have been produced. The produced powders consist of supersaturated solid solution of Al in Nb (bcc) and possess good compactibility. These powders were consolidated by HIP, and the high temperature strength was estimated for the consolidated bodies. Furthermore, we began to develop the technique for in-situ measurement and control of the powder size distribution during atomization.抄録全体を表示PDF形式でダウンロード (1709K) -
浅野 峰生, 永井 直樹, 川崎 亮, 渡辺 龍三1996 年 43 巻 11 号 p. 1273-1278
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーMonosized spherical powders of Pb-Sn alloy were prepared by pulsated orifice injection method (POIM). The apparatus was devised for injecting molten metal from a small orifice by a clipping action of a pressure transmitting diaphragm driven by a piezoelectric actuater. Each pulse pressure, induced by the displacement of the diaphragm, produced one liquid droplet having a size almost equal to the orifice diameter. The effect of the process parameters of waveform, characterized as rise time, hold time and fall time, on the particle formation and size scattering has been discussed. The shape of the obtained particles is spherical with smooth surface covered with very thin layer of SnO2 which is less than 10Å as detected by auger electron spectrocopy.抄録全体を表示PDF形式でダウンロード (3220K) -
粉末粒径の制御熊谷 良平, 吉武 雅美, 岩津 修, 時實 正治1996 年 43 巻 11 号 p. 1279-1282
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーThe study on the operation practice of plasma rotating electrode process (PREP) was carried out. The experiments were performed under the condition with deflection of the center of the plasma from that of the electrode on the six kinds of metals. It was concluded that the particle size distribution was obtained uniformly from any kinds of metals and the average particle diameter from each electrodes were in proportion to the reciprocal number of rotating angular velocity. The coefficient of each metals were suggested on the practical application.抄録全体を表示PDF形式でダウンロード (1477K) -
馬越 幹男, 吉冨 俊之, 上野 貴博, 加藤 昭夫1996 年 43 巻 11 号 p. 1283-1288
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーThe fine powders were prepared by the explosion of iron, nickel, copper and niobium wires in air or under an argon gas atmosphere, which resulted from electric discharge. Concerning the collected powders, the properties and metal contents were examined.
The average particle. sizes which were measured by the centrifugal sedimentation method were less than 1.0μm in all powders, and decreased to 0.3-0.5μm with an increase in the energy ratio. They also did not depend on the kind of wire and atmosphere. The crystallite sizes of the oxide powders made from iron and nickel wires in air decreased with an increase in the energy ratio, and became to constant value, 40-50nm at higher energy ratio. The products obtained in air were mainly oxides, and ones obtained under an argon gas atmosphere were metal and oxides. Reducing the energy ratio led to increasing in the metal contents in the powders, which prepared by the explosion of nickel, copper and niobium wires under an argon gas atmosphere, to 40, 100 and 30%, respectively.抄録全体を表示PDF形式でダウンロード (1865K) -
新見 義朗, 岩津 修1996 年 43 巻 11 号 p. 1289-1293
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーNew sintering procedure of ODS-Ni powder which has very poor sinterability in an inert or a reductive atmosphere has been studied employing Ni-ZrO2 powder. It was found that sintering of Ni-ZrO2 powder was extremely accelerated by undergoing pre-sintering treatment in an atmosphere of air prior to ordinary sintering in a reductive atmosphere. In presintering process, caused by the mass-transfer of Ni to the surface of Nickel oxide layer from the matrix, NiO layer free from ZrO2 particles formed on the outside of the original matrix surface, and the presence of this NiO layer free from ZrO2 particles contributed to acceleration of sintering in subsequent ordinary sintering process. But if the pre-sintering temperature exceeded 1273K, the bending strength of the sintered body was lowered caused by coarsening and aggregating of ZrO2 particles.抄録全体を表示PDF形式でダウンロード (4292K) -
湯瀬 栄一郎, 松田 光明, 大塚 一雄, 田上 道弘1996 年 43 巻 11 号 p. 1294-1299
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーThis paper describes a new method of preparing Co-P spherical powder by use of reducing agent in an aqueous solution. A fixed proportion of reducing agent, complex agent and pH buffer agent was mixed into an aqueous solution with a metallic salt solution. As the result, alloy powder was obtained. At the fixed reaction temperature of 363K, the adequate condition was searched by charging the proportion of above-mentioned agents. The obtained powders were examined by SEM, TG-DTA, XRD, EPMA and ICP. Most of spherical particles were confirmed to be amorphous by XRD and SEM. Chemical analysis of thus obtained particles showed that main elements were Co and P.抄録全体を表示PDF形式でダウンロード (1842K) -
柏井 茂雄, 山田 和俊, 高橋 輝男, 元山 宗之1996 年 43 巻 11 号 p. 1300-1304
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーBK X-ray spectra from mechanically alloyed (MA) Ti-hBN powders were measured precisely using an electron probe microanalyzer (EPMA), in order to investigate the reaction progress of this system. Their spectra features were discussed in comparison with mechanically ground (MG) hBN oowders.
At the early stage of MA, the main BK band at 6.9nm was almost unchanged, while 6.5nm satellite peak intensity was increased. From the result of milling of hBN alone, it was considered that hBN was changed into amorphous BN (aBN) in consequence of refinement, but B state of this aBN was still remained as same as that of hBN. BK spectra of 144ks MA powder was clearly different from that of TiB2, in spite of the observation of TiB2 by X-ray diffraction measurement. This spectrum was in good agreement with the combined spectrum with aBN and TiB2 spectrum. In conclusion the excess of B was remained still as aBN after 144ks MA.抄録全体を表示PDF形式でダウンロード (324K) -
真鍋 明1996 年 43 巻 11 号 p. 1306
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (90K) -
櫻井 茂徳1996 年 43 巻 11 号 p. 1307-1312
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーFacing with the Mega Competition Age, P/M industry in Japan has recognized that collaboration among firms and academics, particularly in the basic and scientific fields, may be the most effective procedure for increasing P/M industry competitiveness. In this paper, assessment of P/M R&D priorities, which was conducted by " JSPM Automotive Sintered Parts Committee " estab-lished in 1995, is reported. 50 participants, including academics, end users, part suppliers, powder producers, replied to an R&D priority questionnaire. The questionnaire consisted of 12 questions concerning fatigue, compaction, dimensional accuracy, densification, powder improvement, standardization of test methods and joining technique. Fundamental study on P/M Fatigue and Computer Simulation for powder compaction were given top R&D priorities.抄録全体を表示PDF形式でダウンロード (517K) -
武田 義信1996 年 43 巻 11 号 p. 1313-1317
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーPowder metallurgy, particularly technology of sintered steel component manufacturing has been looked upon a matured technology. Modern development in computer and/or other technologies revealed that PM technology has potential to be evolved. Since these years, the scientific research on fundamental issues of PM parts manufacturing has been recognized as an urgent and important issue by the European and American PM industries, therefore a number of collaboration programs have been initiated.
The tiding activities in the field of iron and steel powder metallurgy in Japan Society of Powder and Powder Metallurgy (JSPM) let Japanese PM industries have serious concern about world-class competitiveness of the industries in the future without JSPM's appropriate activities in this field.
This paper explains some typical examples of practical issues in the industries and technical topics to be openly discussed and investigated among the members of JSPM, particularly by academic researchers under collaboration with the industries.抄録全体を表示PDF形式でダウンロード (1418K) -
藤木 章1996 年 43 巻 11 号 p. 1318-1322
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーPM parts offer many advantages such as machining free and freedom of alloy design, so a lot of PM parts have been adopted for automobile.
Several car manufacturers started mass production in trans plants of oversea and adoption of local parts because of increasing value of Japanese yen. So the increasing trend of domestic PM parts shipments is not strong.
In this report the situation of PM parts and automobile industry is described and the needs of automobile industry for PM parts and the seeds of PM parts technologies are also explained. The perspective of new PM parts technologies for automobile is described as the summing-up.抄録全体を表示PDF形式でダウンロード (4396K) -
山田 淳一, 菖蒲 次憲1996 年 43 巻 11 号 p. 1323-1327
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーThe "LogiX" tooth profile making up for some demerits of Involute tooth profile excelled in surface durability and wear-abrasion resistance because of many points on the tooth profile having being zero relative curvature and specific sliding. The usage of this tooth profile can expand the application fields of P/M gears which have been limited in the past due to their lower surface durability and wear-abrasion resistance. Furthermore, it makes possible to use conventional material in exchange for expensive high strength material and to eliminate the heat treatment process. This report will show a characteristic of "LogiX" tooth profile, basic properties and the application on it to oil pump gears. This profile is now under the application in mass production for the Diesel Engine Oil Pump gears.抄録全体を表示PDF形式でダウンロード (1284K) -
佐藤 克明, 坂 勉, 酒井 純, 高木 善昭1996 年 43 巻 11 号 p. 1328-1332
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーThe pulleys are used to be produced by powder metal due to cost performance and high productivity. Recently, the timing belt pulleys for automotive engine are required extra high functions which have sensor or light weight, and the complex shape pulleys are tend to increase. This report introduces the examples of the design and engineering of these pulleys as follows.
1)The light weight pulleys with thin wall curtain shape rim are lighter than stamping pulleys.
2)The cam shaft pulleys with sensing cam are manufactured as utilizing powder flow during compacting.
3)The crank shaft pulleys with sensing cam at flange portion for miss fire detection have high accuracy of angle phase between key way and sensing cam.抄録全体を表示PDF形式でダウンロード (2470K) -
三浦 秀士, 馬場 剛治, 長谷 尚彦, 川上 雄士, 石橋 章義1996 年 43 巻 11 号 p. 1333-1338
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーMetal injection molding (MIM) is a suitable processing route for the mass production of complex-shaped and high performance components. Therefore, MIM process is hoped to be quite useful for improvement of the quality and productivity in the automotive sintered parts.
This study has been performed to develop the high performance ferrous sliding abrasive wear-resistant materials through MIM process. A prealloyed powder (SCM440) was used as the matrix and also 3mass%TiN powder was added to improve the wear-resistance. Those compacts were densified to about 95% of relative by sintering, and the final carbon content was almost exactly controlled to be 0.4mass% by adjusting the debinding and sintering atmospheres and conditions. Sintered compacts showed the dual homogeneous microstructures consisted of ferrite and fine pearlite, and the pores and TiN powder particles were distributed uniformly, regardless of the injecting direction. Thus, the wear characteristics were not influenced by the injecting direction. Injection molded SCM440 steel showed the same wear-resistance as the wrought SCM440 steel. However, addition of 3mass%TiN powder caused a remarkable improvement of wear-resistance, which indicate that MIM process has enormous potential to produce high performance ferrous composites for the automotive parts.抄録全体を表示PDF形式でダウンロード (5445K) -
近藤 幹夫, 竹本 恵英1996 年 43 巻 11 号 p. 1339-1342
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーIt is essential for improving the dimensional tolerance of complex P/M parts to uniformly fill powders in a die cavity. This study is aimed at clarifying the powder behavior in filling the die cavity. A visual apparatus was developed for observing the powder behavior. Using this apparatus, the effects of the die cavity shape and feed-shoe speed on the filling behavior, density and particle size segregation of filled powders were investigated for gravity filling of atomized iron powders.
It is clarified that the particle size segregation in filling occurs independently on the shoe speed and die cavity shape. Coarse particles segregate in the place where the powder falls along the angle of repose, while fine particles segregate in the thin-walled part and the position where the empty space finally disappears.抄録全体を表示PDF形式でダウンロード (5390K) -
斎藤 実, 寺田 修, 鈴木 寿1996 年 43 巻 11 号 p. 1345-1349
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーTool materials having high corrosion resistance as well as excellent mechanical properties and low density have recently been required for producing, for instance, seaming tool used for fixing a steel cap on different juices can. In case of seaming tools, it is well known that all sorts of juices leaking during the operation are apt to attack the tool materials, resulting in shortening the life time, especially, of seaming roll. Then, attending to titanium carbide based cermet, the study for developing the tool material as above was carried out.
It was suggested that TiC-55mass%(Ni-Mo-Cr) low carbon cermet containing about 25mass%Mo and 3mass%Cr in binder, was the most adequate for the material. In other words, the cermet showed a superior corrosion resistance, having HV900-1000 and transverse-rupture strength of about 2.1 GPa. These properties varied naturally according to sintering condition of the cermet.抄録全体を表示PDF形式でダウンロード (4482K) -
岩崎 源, 柳瀬 希昭, 森 隆資, 馬渕 守, 東 健司1996 年 43 巻 11 号 p. 1350-1353
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーIn this work, ZK61 (Mg-6.0mass%Zn-0.7mass%Zr) and AZ91 (Mg-9.0mass%Al-0.7mass%Zn) Mg alloys were prepared by P/M method with fine alloy powders and the mechanical properties at room temperature and the superplastic properties at 573K for the P/M Mg alloys have been investigated comparing with those for ingot-metallurgy processed(I/M) ZK60 and AZ91 Mg alloys. The P/M Mg alloys exhibited higher strength and higher 0.2% proof stress at room temperature, than those for the I/M Mg alloys. The P/M Mg alloys showed superplastic behavior at 1-order higher strain rates than the I/M Mg alloys. It is likely that these excellent mechanical properties for the P/M Mg alloys are attributed to the very small grain sizes.抄録全体を表示PDF形式でダウンロード (3060K) -
小林 厚子, 山本 直一, J.L. Kirschvink1996 年 43 巻 11 号 p. 1354-1360
発行日: 1996/11/15
公開日: 2009/12/04
ジャーナル フリーFerritin, the iron storage nonhaeme-protein contains a ball of hydrated iron oxides (Fe2O3⋅nH2O) in its core, which is paramagnetic at room temperature. It is reported the hydrated iron oxide is the precursor of magnetite (Fe3O4) in the magnetotactic bacteria and polyplacophoran mollusks. It is not known whether this is the case for other organisms. In our study, we report the first detection of magnetic material in the human brain through the use of SQUID magnetometry. The material was characterized by HRTEM and EPMA. It was affirmed the material was a single crystals of magnetite. Magnetite distribution in tissues might be related with ferritin, if the core of these molecules are involved in magnetite formation in human. In general, both Perls staining and MRlmaging methods are adopted routinely for determining the relative amounts of Fe(+III) in the whole brain, which is dominated by ferritin. Both methods suggested high levels of Fe(+III) distribution in the globus pallidum, putamen, caudate, internal cerebral capsule of the cerebrum, red nucleus of the mid brain and lower concentrations in the substantia nigra of the mid brain and the dentate nucleus of the cerebellum. Whereas, our experiments showed that the distribution of magnetite is rather even in the whole human brain averaging 4 ng per gram of tissue (except for the meninges, where it is 20 times higher).抄録全体を表示PDF形式でダウンロード (4221K) -
落合 鍾一, 宗宮 重行, 山崎 道夫, 村上 雄1996 年 43 巻 11 号 p. 1361-1367
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーThe (Ni3AI+NiAl) intermetallic compounds were produced by MA-HIP method. There are two cases for the sintered specimens; the one was produced using only elemental powders (EP specimen) and the other was produced using both NiAl prealloyed and nickel powders (PP specimen). Those alloys were subjected to the heat refining process. The microstructural change and mechanical properties were investigated. It was found that the fine particles with the size of less than 3μm were obtained by MA process. EP specimen showed very fine microstructures with almost full density. On the other hand, PP specimens showed higher relative density with increasing HIP temperature. After heat-refining treatment, EP specimen had fine structure, since the size of the prior P grains and the width of lamella decreased comparing with PP specimens. There was the tendency for the mechanical properties of PP specimens to approach those of EP specimen with increasing HIP temperature. The strain rate sensitivity exponent, m value, was found to be about 0.52 for EP specimen and 0.34 for PP specimen at 1073K. This high m value suggests the occurrence of superplastic deformation especially in EP specimen.抄録全体を表示PDF形式でダウンロード (3249K) -
M.Sherif El-Eskandarany, Toyohiko J. Konno, Mamoru Omori, Mikio Ishiku ...1996 年 43 巻 11 号 p. 1368-1373
発行日: 1996/11/15
公開日: 2009/05/22
ジャーナル フリーA new process for preparation of nanocrystalline WC powder at room temperature is reported. In our process, a mixture of WO3, Mg and graphite powders are mechanically reacted under an argon gas atmosphere using a high energy ball mill. After few kiloseconds of milling (11 ks), numerous fresh surfaces of the powder are created by the repeated impact and shear forces of the balls. After 86 ks, the fresh Mg particles that have high reducing potential are oxidized, whereas the WO3 is reduced completely to a metallic W powder. In parallel, a solid state reaction between W and the unreacted graphite powders takes place to yield a fine powder of WC. At the final stage of milling (173 ks), composite WC/MgO powder particles is obtained. The MgO is removed from the matrix of WC using a leaching technique. The residual WC powder was then consolidated in vacuum at 1963 K with a pressure of 19.6 - 38.2 MPa for 0.3 ks, using a plasma activated sintering method. No binding material was used during the consolidation procedure. Under these consolidation conditions, the obtained sample is fully dense (>99.5 % theoretical density) with nanoscale grain size of about 25 nm in diameter. The elastic properties and the hardness of the consolidated sample have been determined. A model for the formation of WC at room temperature is proposed.抄録全体を表示PDF形式でダウンロード (6367K)
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