巻号一覧
49 巻, 6 号
選択された号の論文の14件中1～14を表示しています
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深津 保2002 年 49 巻 6 号 p. 471-476
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーThis is my memorable note on my way for 50 years in a cemented carbide tool manufacturer.
I would like to show you the several topics through-out my experience developing hard materials such as cemented tungsten carbide, titanium carbide base cermets, or aluminum oxide base ceramics and their application to various industries.抄録全体を表示PDF形式でダウンロード (6118K) -
松野 進, 梅川 聖, 飴山 惠2002 年 49 巻 6 号 p. 479-485
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーThe high strain powder metallurgy (HS-PM) process was applied to an SUS316L gas atomized powder by 360ks mechanical milling (MM) with a planetary ball mill under an Ar atmosphere. The MM powder was annealed at 1073 K, 1173 K, 1273 K. Each structure was investigated using XRD and TEM/EDS. It was confirmed that as-MM powder consisted of an ultra fine (α+γ) microduplex structure. It was supposed that the a phase was formed as the HS-PM process by increasing free energy of the austenitic phase. Fine grain structure with its grain size of 2.3μm composed of fine carbides and γ phase was obtained when MM powder was annealed at 1073 K for 3.6 ks. It was also confirmed that these fine carbides restrain the grain growth. But at 1173 K and 1273 K, the fine carbides were not seen, so that grain size increased drastically.抄録全体を表示PDF形式でダウンロード (6717K) -
藤井 紘己, 芳仲 捷, 廣田 健, 池上 隆康, 山口 修2002 年 49 巻 6 号 p. 486-490
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーA YAlO3(hexagonal) solid solution with α=0.3678nm and c=1.046 nm crystallizes at 880° to 935°C from an amorphous material prepared in the molar ratio Y3+/Al3++=3:5 by a solution technique using hydrazine. The hexagonal YAIO3 phase transforms to Y3Al5O12(YAG) at 1005° to 1075°C. The YAG powder calcined at 1200°C can be densified to transparency in a vacuum for 2h at 1600°C without additives.抄録全体を表示PDF形式でダウンロード (4928K) -
釘本 弘訓, 上原 雅人, 榎本 尚也, 北條 純一2002 年 49 巻 6 号 p. 491-495
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーSi3N4-BN nanocomposites are formed via phase separation and crystallization of amorphous Si3N4-BN composite powder during sintering. Amorphous Si3N4-BN composite powders were prepared by a vapor phase reaction method. To clarify the effect of applied pressure and sintering aid on the phase separation and crystallization behavior, the composite powders were hot-pressed and pressurelessly sintered with and without Y2O3-Al2O3 sintering aid. Si3N4 crystallized into α-phase at 1600°C without sintering aid, and into β-phase at 1400°C with sintering aid. It was found that the crystallization of Si3N4 and BN was promoted by applied pressure and sintering aid. On the other hand, the phase separation of BN from Si3N4 occurred around 1400°C regardless of applied pressure and sintering aid.抄録全体を表示PDF形式でダウンロード (3608K) -
山元 洋, 尾崎 康亮2002 年 49 巻 6 号 p. 496-502
発行日: 2002/06/15
公開日: 2010/07/12
ジャーナル フリー(Sr⋅Ba)-La-Co M-type ferrite fine particles were prepared by the chemical coprecipitation and subsequent heat-treatment method. The chemical reagents used for the experiment were FeCl3⋅6H2O, BaCl2⋅6H2O, SrCl2.6H2O, LaCl3⋅7H2O, and CoCl2.6H2O. The chemical coprecipitation process was applied to the samples having the formula. {(SrO)1-x⋅(BaO)x⋅n/2(Fe2O3)}100-Y-Z(La2O3)Y(CoO)Z (n=6.0-12.0, x=0.0-1.0, y=1.0-10.0, z=1.0-10.0). The solution containing Sr2+, Ba2+, Fe3+, La3+, and Cot2+ was poured into solution of NaOH (pH=13.0). The precipitated products were boiled for 2h and they were carefully washed with water and dried. The obtained fine particles were heated at 950 to 1100°C for 2h in air to obtain the single phase of (Sr⋅Ba)-La-Co M-type ferrite fine particles. The best magnetic properties were observed for the sample with the composition of {(SrO)0.8⋅(BaO)0.2⋅3.5(Fe2O3)} 88.0 (La2O3)6.0(CoO)6.0, and magnetic properties were as follows: σs= 84.8 × 10-6 Wb⋅m/kg (67.5 emu/g), σr=42.8 × 10-6 Wb⋅m/kg (34.1 emu/g), HcJ=476.6 kA/m (5.98 kOe) and Tc=452.6°C.抄録全体を表示PDF形式でダウンロード (1566K) -
木原 茂文, 石田 浩修, 森岡 真一2002 年 49 巻 6 号 p. 503-509
発行日: 2002/06/15
公開日: 2009/12/04
ジャーナル フリーA program for analyzing density distribution in powder compact during pulse current sintering process has been developed. Temperature distribution during the sintering process is analyzed by the heat conduction finite element method, where the heat generation per unit volume induced by the electric current is considered. The densification is evaluated based on the temperature distribution. The effect of plastic flow, diffusion and creep phenomenon are taken into account in the densification analysis. Calculated temperature and densification histories are compared with the test results of the pulse current sintering and hot press sintering. The calculated results are in good agreement with the experimental ones. The validity of the algorithm was demonstrated.抄録全体を表示PDF形式でダウンロード (3690K) -
鰐部 吉基2002 年 49 巻 6 号 p. 512
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (94K) -
宮原 一哉, 呉 克鵬2002 年 49 巻 6 号 p. 513-517
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーEnvironment and energy related issues, such as green house effect, air and soil pollution and defiecncy of energy resources should be the most important ones in the 21st century. Materials scientist and engineers are considered to be also responsible for solving these problems. The present author is making researches on the materials and technology associated with these issues. The recent results of his researches on (1) lead free solder alloys, (2) high damping and high strength Fe-Cr-Mn alloys, (3) ODA-MA (oxide dispersion strengthened mechanically alloyed) ferritic materials and (4) application of positron annihilation measurement for the investigation of fatigue damage accumulation behavior and for the evaluation of materials life are reported briefly in this article.抄録全体を表示PDF形式でダウンロード (1785K) -
伊藤 芳典, 針幸 達也, 佐藤 憲治, 三浦 秀士2002 年 49 巻 6 号 p. 518-521
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーAlthough the thermal debinding method is mainly used in the industrial production of MIM components, this method needs a long debinding time. To solve this problem, some of new binder systems or debinding methods have been developed and reported so far.
In this study, to clarify the behavior of various binders during the debinding step, the pyrolyzed temperature and solubilities of binder resins and wax were examined. Then, some of binder systems were investigated to be suitable or not for thermal and solvent debinding from the following viewpoints. One is that the binder resins should be pyrolyzed at three temperature ranges during thermal debinding, and the other is that the above 70% of binder resins should be removed by solvent debinding. The binder system achieved above concepts was composed of polypropylene, polymethyl methacrylate, paraffin wax and stearic acid, the composition of which was 30mass%, 40mass%, 29mass% and 1 mass%, respectively. From the thermogravimetric analysis, it was found that they were pyrolyzed at about 523 K, 623 K and 703 K, and almost 70% of binder resins were removed by solvent debinding with hexane.抄録全体を表示PDF形式でダウンロード (288K) -
北島 明子, 清水 透, 依田 智, 増井 孝実2002 年 49 巻 6 号 p. 522-526
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーWe have studied improvement of debinding process, especially binder extraction method, which is bottle-neck for MIM process. The binder can be extracted by using supercritical carbon dioxide. This extraction method in the MIM process is proved to reduce the debinding time, compared with thermal method. In this study, we report excellent results: the mechanical and physical properties by using, myristic acid and palmitic acid, as dispersing agents, which are dissolved in supecritical carbon dioxide, compared with stearic acid.抄録全体を表示PDF形式でダウンロード (1641K) -
奥山 秀男, 小澤 清, 大野 悟, 目 義雄2002 年 49 巻 6 号 p. 527-530
発行日: 2002/06/15
公開日: 2009/12/04
ジャーナル フリーUltrafine particles of Pd-TiN system have been synthesized by "reactive plasma-metal" reaction, i.e., arc melting, vaporization and deposition of a binary Pd-Ti alloy in an atmosphere of a nitrogen-hydrogen mixed gas. X-ray diffraction and transmission electron microscope measurements have been carried out for the resulting particles. It is found that the typical morphology of the resulting ultrafine particles is a dumbbell-like particle consisting of single phases of Pd and TiN particles with the particle sizes of -20nm and -50nm, respectively. In addition, the ultrafine particles, synthesized from the parent alloys containing more than 60at%Ti, show solid solutions of Pd and TiN.抄録全体を表示PDF形式でダウンロード (2018K) -
三浦 秀士, 中川 卓洋, 松田 光弘2002 年 49 巻 6 号 p. 531-533
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーW-Cu system alloys are promising for thermal managing applications such as microelectronic devices because of the low thermal coefficient of W and the high thermal conductivity of Cu. These materials have been produced by conventional Cu-infiltration sintering or liquid-phase sintering. However, the infiltration sintering process has complicated and many steps, and also the constituent phases are often segregated in the form of Cu pool.
For the homogeneous constituent phases, in this study, the new concept of sintering was suggested by the application of the W-Cu composite powders to MIM process which is hoped to be an advanced powder processing technique for near net shape forming the high density, high performance, and complicated components.
Optimal thermal conductivity of the W-15mass%Cu-0.5mass%Co composite powder compact was obtained by sintering at 1673 K for 3.6 ks in H2; the relative density and the thermal conductivity were 92.5% and 151.0 W/mK, respectively.抄録全体を表示PDF形式でダウンロード (3036K) -
中村 満, 高橋 弘美, 菅谷 好美2002 年 49 巻 6 号 p. 534-540
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーTo study rapid sintering by induction heating, we used high strength-alloyed steel powder, partially diffused powder of 4mass%Ni-1.5mass%Cu-0.5mass%Mo-0.3mass%C-bal. Fe. In this rapid sintering, the degassing process, diffusion of additional alloying elements and evolution of a Martensitic or Bainitic structure in the matrix were proved to play a very important role. Thus, the substantial controlling factors were the holding time for degassing and the diffusion. Experimental results showed that this process required a higher sintering temperature compared with the a continuous furnace, but that the sintered materials processed a higher radial crushing strength (R.C.S) by changing the holding time. Although the high strength-alloyed steel requires, in general, a longer time for diffusion of additional alloying elements, the holding time was only 3-4 minutes in the present process. The optimum condition appeared to be a sintering temperature of 1573 K for 120-180s with a temperature increase time of 65 s; the RCS data attained was about 1400MPa.抄録全体を表示PDF形式でダウンロード (6629K) -
鰐部 吉基, 伊藤 孝至, 横山 誠二, 草加 勝司2002 年 49 巻 6 号 p. 541-544
発行日: 2002/06/15
公開日: 2009/05/22
ジャーナル フリーThis invited lecture begins with a simple briefing of the topics which have been presented in the Special Interest Program C: Jazz Up Your Process: Technology to Reduce Component Variation in the PM2TEC2001 held in New Orleans last May. Then the régime of the content in our presentation there follows, in which it is emphatically concluded that (1) the characterization and quantitative assessment of pores should be methodologically developed and established so that the quantification make it possible to compare correctly and discuss suitably with relationships to operation factors and product characteristics in powder metallurgy, and (2) systematic researches of this kind are important and should be further progressed.抄録全体を表示PDF形式でダウンロード (413K)
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