巻号一覧
47 巻, 2 号
選択された号の論文の20件中1～20を表示しています
- |<
- <
- 1
- >
- >|
-
石井 敏夫, 島 順彦, 植田 広志, 権田 正幸, 岡山 史郎2000 年 47 巻 2 号 p. 121-125
発行日: 2000/02/15
公開日: 2009/12/04
ジャーナル フリーMicrostructure of α-Al2O3-coated turning inserts whose tool lives were longer than K-Al2O3-coated ones have been investigated. These inserts were coated successively with a TiN layer, a MT(moderate temperature)-Ti(C, N)layer, a bonding layer, and a α-Al2O3 layer on cemented carbide inserts by using chemical vapor deposition(CVD). X-ray diffraction, SEM and TEM were used to characterize the coatings, and following characteristics were found.
(1) Epitaxial growth was observed in a column of MT-Ti(C, N) twinned grains, bonding layer twinned grains and α-Al2O3 grains by cross-section TEM, where(100)-planes of the α-Al2O3 grains were parallel with(110)-planes of both the MT-Ti(C, N)grains and the bonding layer grains, and(003)lattice fringes of the α-Al2O3 grains continue almost linearly from {111} lattice fringes of the bonding layer grains.
(2) (120)-planes of the α-Al2O3 grains and (211)-planes of both the MT-Ti(C, N)grains and the bonding layer grains in the column were parallel to the substrate, too.
(3) Many steps at the surface of vertical-plane-shape protrusions formed along the twin boundaries on the surface of the bonding layer, might promote the epitaxial growth of α-Al2O3 grains on the bonding. layer.
(4) The above mentioned microstructure agrees with X-ray diffraction results on the MT-Ti(C, N) layer and the α-Al2O3 layer. This may mean that the epitaxial growth will be found in many columns in the α-Al2O3-coated turning inserts.
The above mentioned epitaxial growth and the protrusions between the bonding layer grains and the α-Al2O3 grains are considered to be the cause for improved α-Al2O3 layer adherence and longer tool life.抄録全体を表示PDF形式でダウンロード (4213K) -
山崎 道夫, 木暮 嘉明, 新井 隆2000 年 47 巻 2 号 p. 126-130
発行日: 2000/02/15
公開日: 2009/12/04
ジャーナル フリーSi and Cu powders are added to Al powder and the mixtures compacted are heated at 620 or 600°C for 1 hr. in an argon atmosphere. Based on isothermal phase diagrams of Al-Si-Cu system(Al corner)at 620 and 600°C, the amounts of liquid phase are varied from10to60mass%. The relative densities of the sintered compacts are analyzed by using a regression analysis program; the relative densities are expressed as functions of sintering temperature, amount of liquid phase, ratio of Cu/(Cu+Si), and the others. Uniformity of shrinkage after liquid phase sintering is also analyzed.抄録全体を表示PDF形式でダウンロード (434K) -
地主 弘幸, 京極 秀樹, 篠原 和充, 中山 英樹2000 年 47 巻 2 号 p. 131-136
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーThe effects of carbon (C) addition and debinding temperature on sintering behavior of Cr-Mo steel compacts shaped by metal injection molding were invetigated to carry out the control of C content of the sintered compacts. The specimens were made of SCM415 steel powder and additional C powder with polyamide binder. The amount of C addition was varied from Og to 0.6g per 100g of metal powder. The specimens were debound in air at temperatures ranging from 553K to 603K for 7.2ks, and were sintered in argon gas at 1623K for 7.2ks. The relationship between carbon (C) and oxygen (O) contents of debound compacts versus those of sintered compacts was analyzed by introducing a parameter, ΔCd=Cd-aOd (a=C/O atomic weight ratio) which represents the stoichometric ratio of C and O contents of debound compacts (Cd and Od, respectively). The obtained results showed that the reaction MxO+C→xM+CO (M=Metal element) is dominant for reducing oxides during sintering process and the excess or shortage of C reducing oxides in compact can be estimated successfully by ΔCd introduced in this study.抄録全体を表示PDF形式でダウンロード (3922K) -
阿部 正紀2000 年 47 巻 2 号 p. 138
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (69K) -
金子 裕治, 徳原 宏樹, 笹川 泰英2000 年 47 巻 2 号 p. 139-145
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーIn order to obtain high energy Nd-Fe-B sintered magnets, extensive studies on processing technologies have been done; (1) Increasing the amount of Nd2Fe14B main phase with keeping the ability of densification through a liquid phase sintering, (2) Controlling the microstructure of sintered magnet to be dense, fine and uniform, (3) Achieving high orientation of Nd2Fe14B main phase grains.
With a new casting process for Nd-Fe-B alloy, improving the preparation of fine powders having a sharp distribution of particle size and to be better lublicating characteristics, and adopting the special CIP process, we have succeeded in obtaining the highest 444 kJ/m3 (55.8 MGOe) magnet. Based on these advanced tecnologies, we can start to massproduce super high performance 400 kJ/m3 Nd-Fe-B magnets for computer applications, communications and so on.抄録全体を表示PDF形式でダウンロード (3456K) -
田中 義和, 相川 芳和, 加藤 信行2000 年 47 巻 2 号 p. 146-150
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーEffect of powder particle size, extrusion temperature and mean strain rate on anisotropy of MnAlC alloy was investigated. The anisotropy proceeding mechanism of MnAlC alloy was considered by anisotropy investigation with specimens during exrusion.
MnAlC powder was made by Ar gas atomizing process, classified fixed particle sizes and was compacted by extrusion at extrusion temperature: 853-993K and mean strain rate: 0.005-0.05/s.
Anisotropy of MnAlC formed was found to improve at lower temperature, finer particle size and lower strain rate. It was considered to be related to the homogeneity of τ phase and the crystal grain size. It was found that anisotropy of MnAlC magnet was increased as deformation right after the start of extrusion and saturated at the part on the way of extrusion.
This phenomenon can be explained by the two deformation areas, one is that dynamic recrystallization proceeds as keeping the former crystal orientation according to the strain induced grain boundary migration mechanism, the other is that dynamic recrystallization proceeds with no relation to the former crystal orientation according to the nucleation and growth mechanism.抄録全体を表示PDF形式でダウンロード (4912K) -
沖本 邦郎, 和泉 克尚, 豊田 幸夫, 細川 誠一2000 年 47 巻 2 号 p. 151-154
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーFor the purpose of producing ferrite part with a complicated shape which has different alignment of the ferrite crystallites, the feasibility of combined sinter joining method was studied. Inner disk was compacted under magnetic field of 0-915 kA·m-1 and outer ring compacted under non-magnetic field, respectively. The two compacts was assembled into a unit. CIP treatment was operated to the combined compact and then sintered at 1225°C. It was found that the joint strength of the sinter joined compact produced under the magnetic field is superior to that of the compact fabricated under the non-magnetic field, and that the optimum magnetic field is 250 kA·m-1 because the probability of occurrence of cracks may be enhanced by applying the magnetic field of higher than 250 kA·m-1. The maximum joint strength of 50.8 MPa was obtained by applying the pressure of 100 MPa for the combined green compact at the CIP treatment.抄録全体を表示PDF形式でダウンロード (294K) -
山元 洋, 関 浩太2000 年 47 巻 2 号 p. 155-159
発行日: 2000/02/15
公開日: 2009/12/04
ジャーナル フリーSingle phase Sr-La-Co M-type ferrite fine particles were prepared by the chemical coprecipitation and subsequent heat treatment. The chemical reagents used for an experiment are FeCl3⋅6H2O, Sr(NO3)2, La(NO3)3⋅6H2O, Co(NO3)2⋅6H2O and CoCl2·6H2O. The chemical coprecipitation composition were chosen according to the formula {(SrO)·n/2(Fe2O3)}100-x-y(La2O3)x(CoO)y, where n was fixed at 7.0 and x at 1.5 and y was varied between 1.0 and 10.0. A water solution containing Sr2+, Fe3+, La3+ and Co2+ was poured into solution of NaOH (pH=13.0). Aqueous suspensions containing the coprecipitated products were boiled for 2h, and they were carefully washed, filtrated and dried at 80°C for 12h. The obtained fine particles were heated 950 to 1100°C for 2h in air to get single phase Sr-La-Co M-type ferrite fine particles. The conditions determined as optimum for preparing the fine particles with the best values of σs=90.2×10-6 Wb·m/kg (71.8emu/g), σr=45.1×10-6 Wb·m/kg (35.9emu/g), Hcj=525.2kA/m (6.60kOe) and Tc=453.9°C are as follows: composition; Sr2+0.812La3+0.045Co2+0.045Fe3+9.236O2-19; heat treatment; 1000°C×2h in air, the average particle size; 0.3-0.4μm.抄録全体を表示PDF形式でダウンロード (1536K) -
山元 洋, 小原 学2000 年 47 巻 2 号 p. 160-164
発行日: 2000/02/15
公開日: 2010/07/12
ジャーナル フリーSr-La-Co M-type Ferrite fine particles were prepared by mechanical compounding using the planetary ball-mill and subsequent heat treatment. This experiment was carried out to investigate the effect of La2O3 and Co3O4 additives on the magnetic properties of Sr M-type ferrite fine particles. The optimum condition of making Sr-La-Co M-type ferrite fine particles and some properties of typical specimens are as follows; chemical composition: SrO·6Fe2O3; additive: 2wt%La2O3 and 0.3wt%Co3O4; planetary ball-mill condition: 300rpm×lh; heating condition: 1100°C×1h; magnetic properties are σs=86.5×10-6 Wb·m/kg, Hcj=488kA/m, Tc=453.1°C.抄録全体を表示PDF形式でダウンロード (1425K) -
北本 仁孝, 中川 茂樹, 阿部 正紀, 直江 正彦2000 年 47 巻 2 号 p. 165-170
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーThe present paper describes synthesis techniques of ferrite thin films by the facing-targets sputtering and the ferrite-plating methods. The difference in microstructure, crystallinity and magnetic properties of the ferrite films deposited by the two deposition methods is caused by the difference in energy which atoms and ions have in order to migrate on and around substrates. Co-M ferrite films (M=Zn, Ni) deposited by the two methods for magnetic recording media were investigated. Since the sputtered atoms have higher migration energy than the plating ions, the sputter-deposited Co-Zn ferrite films exhibited closely packed finer microstructure, better crystallinity, and higher mechanical strength. Co-Ni ferrite-plated films had excellent perpendicular magnetic anisotropy though the microstructure must be improved to apply to the magnetic recording media. The ferrite plating has the advantages in coating micrometersize particles used as magnetically separable carriers such as for medical applications because it is a wet process.抄録全体を表示PDF形式でダウンロード (4043K) -
張 福春, 北本 仁孝, 阿部 正紀2000 年 47 巻 2 号 p. 171-174
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーThe present paper describes the effects of adding Ni2+ ions into Co ferrite films fabricated by the spin-spray ferrite-plating method for perpendicular magnetic recording media. Surface roughness of the Co ferrite-plated films increased with decreasing their thickness due to grains as large as 100nm formed at the initial growth, though a thin recording layer below 50nm is required for high-density recording media with lower noise level. Adding Ni2+ ions into the films suppressed the formation of such large grains, and the surface of Co-Ni ferrite-plated films was composed of uniform grains of 40-50nm in size. As a result, the surface roughness was reduced from 5-6nm to 3-4nm for 45nm-thick films, and such improvement in the microstructure led to the reduction of media noise.抄録全体を表示PDF形式でダウンロード (1750K) -
浪川 達男, 中川 茂樹, 金田 久美子, 松下 伸広, 直江 正彦2000 年 47 巻 2 号 p. 175-178
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーA perovskite type of (La, Sr)MnO3 films were deposited on SiO2/Si substrates with amorphous surface by using the facing targets sputtering system. La1-xSrxMnyO3 targets were prepared by the conventional sintering method from starting powders of La2O3, SrCO3, and Mn3O4. The Sr and Mn content were strongly affected whether the sputtering gas has included oxygen or not. The film as-deposited at partial O2 pressure Po2 of 0.04m Torr was composed of crystallites with excellent (100) orientation at relatively low substrate temperature Ts. Whether the sputtering gas has included oxygen or not also affected the crystallinity of the films. The 4πMs of as-deposited films increased after post-annealing process, and has reached near that of bulk La1-xSrxMnyO3. The increase of 4πMs seems to be caused by the compensation of the lack of oxygen ions in the perovskite crystal structure. Since the MR response of the films exhibits excellent linearity, these LSMO films seem to be applied for magnetic sensor devices. The linear MR response has remained after post-annealing process.抄録全体を表示PDF形式でダウンロード (288K) -
村瀬 琢, 野村 武史2000 年 47 巻 2 号 p. 179-184
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーThe sintered ferrite tile for radio wave absorbers has been required to extend the frequency band and to reduce the thickness. The composition (NiO)11.4(CuO)7.6(ZnO)31.9(Fe2O3)47.1(Mn2O3)2.0 with a matching thickness of 5.7mm and a frequency band from 30 to 400MHz has been developed by the investigation of sintering conditions. The developed material has higher static susceptibility of rotation magnetization and a narrower interval between the domain wall resonance frequency and the rotation magnetization relaxation time as analysed by complex-permeability spectra. Also the matching thickness is reduced and the absorption band shifts to lower frequencies region compared with the conventional materials. The matching thickness is influenced by the sintered density or Cu segregation in NiCuZn ferrite substituted by Mn2O3.抄録全体を表示PDF形式でダウンロード (4987K) -
近藤 幸一, 千葉 龍矢, 山田 盛一, 大槻 悦夫2000 年 47 巻 2 号 p. 185-188
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーThe power loss (Pcv) in Ni-Zn ferrite was analyzed by combining two methods. That is, Pcv was divided into hysteresis loss (Ph) and residual loss (Pr) from the frequency dependence of the power loss according to the method of Otsuki et al., as a first approach, and also the loss factors attributed to domain wall motion (Pw) and the rotation magnetization (Prot) by adapting the method proposed by Visser et al. as the other one. The hysteresis loss dominates Pcv in the frequency range below 500kHz, while Pr becomes predominant factor in the higher frequency range more than 500kHz. On the other hand, Pw dominates Pcv in the measured frequency range. It was found, by comparing the loss factors obtained by the analyzing methods, that Pr is mainly attributed to the domain wall motion in the lower frequency range and to the both magnetization processes in the megahertz range. It was also found that Pw consists of Ph and another loss factor which can be attributed to the dynamic motion of the domain wall.抄録全体を表示PDF形式でダウンロード (272K) -
佐々木 智恵子, 村瀬 琢, 野村 武史2000 年 47 巻 2 号 p. 189-194
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーThe properties of ferrite granules have a marked effect on the handling of granules and magnetic properties of sintered bodies. However, the factors which affect the properties of granules have not been clear. In this paper, the effect of water content on the properties of MnMgZn ferrite granules has been investigated with special reference to the packing behavior. The granules which were different in water content were characterized by apparent density, flow rate and friction force. In case of loose packing of granules, apparent density and flow rate decreased and friction force increased as water content increased. However, water which was contained within ferrite granules decreased friction force in case of dense packing. Tapping behavior of MnMgZn ferrite granules could be fitted by Kawakita's expression. It was found that the constant "a" from Kawakita's expression indicated flowability of granules in tapping process.抄録全体を表示PDF形式でダウンロード (469K) -
草加 勝司, 今岡 健, 近藤 鉄也2000 年 47 巻 2 号 p. 195-202
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーA fundamental study was made mainly on the (DC) magnetic properties of Fe-Si type magnetic alloys, prepared by the two methods of soft-iron/Fe-21(wt%)Si mixed powders and full alloy powders. In this case, Fe-21Si (eutectic) mother alloy fine was made by high-pressure water atomization and was blended with soft-iron powder to Fe-0-8(wt%)Si compositions.
The results obtained were summarized as follows:
(1) Magnetic induction (B10) have the maximum value in the Si content: 2-3wt%, under the influence of γ-loop on Fe-rich side and Si substitution by Fe in higher Si region, almost for all the sintering temperatures (≥1473K).
(2) Max. permeability (μm) shows the two maximum values in the Si contents: 3 and 7wt%, as partly confirmed of C/W Fe-Si alloy, under the influence of crystal anisotropy and magnetostriction.
(3) Coercive force (Hc) tends to simply decrease with the rise of Si content, except for higher Si region (sintered at 1373K) and to be structure-sensitive as well as max. permeability (μm), depending on pore morphologies.
(4) On a whole, magnetic properties (B10, μm, Hc) of Fe-3, 6.5, 8(wt%)Si-mixed powders are on improved level compared with those of full alloy powders, probably due to good compressibility and sinterability.
(5) Electric resistivity (ρ) increases linearly with the rise of Si content and radially crushing strength (σ) tends to have the maximum value in the Si content: 5wt%, together with higher strain (ε), for all the sintering temperatures (≥1473K).抄録全体を表示PDF形式でダウンロード (3991K) -
Carlos Seiti Kuroda, Tae Youb Kim, Teruyoshi Hirano, Tomoyasu Taniyama ...2000 年 47 巻 2 号 p. 203-207
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーFine particles of bismuth-substituted yttrium iron garnet doped with aluminum, gallium and indium ions are prepared by coprecipitation method. The films with these particles are obtained by dispersing particles on glass substrates with an appropriate epoxy binder. The magnetic and magneto-optical properties of the particles and the films are examined. The lattice sites occupied by aluminum, gallium and indium ions are determined by the relationship between the saturation magnetization and substitution content. The canting of the magnetic moments from the average magnetization axis of the iron ions is deduced in the indium substituted particles. The figure of merit of indium substituted samples remains constant up to the substitution content of 0.5.抄録全体を表示PDF形式でダウンロード (366K) -
Yoshikazu Suzuki, Masanobu Awano, Naoki Kondo, Tatsuki Ohji2000 年 47 巻 2 号 p. 208-212
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーIn situ development of barium hexaferrite, BaFe12O19, particles in 3-mol%-yttria-doped zirconia (3Y-TZP) matrix was studied for the pressureless reactive sintering of 3Y-TZP, BaCO3, and y-Fe2O3 powders at 1250°-1400 °C for 2h. Fine-grained BaFe12O19 particles were homogeneously distributed in fine TZP matrix. Changing sintering temperatures could easily control the size of in-situ-developed BaFe12O19 particles. Submicrometer-sized BaFe12O19 particles were obtained at 1250°-1300 °C, allowing BaFe12O19 particles to be single magnetic domain structure. The 3Y-TZP/20-wt%-BaFe12O19 composite sintered at 1300 °C showed high magnetization and coercivity values, despite the low concentration of ferromagnetic phase. The composite also indicated moderately good mechanical properties.抄録全体を表示PDF形式でダウンロード (2572K) -
石橋 新一郎, 佐藤 寿彦, 横山 勝, 太田 竹男, 山内 五郎2000 年 47 巻 2 号 p. 213-219
発行日: 2000/02/15
公開日: 2009/05/22
ジャーナル フリーIn cultivating biennial produce such as pasture, wheat, turf, etc., in snow-inflicted areas such as Hokkaido or part of Honshu, snow mold brought about by the causes including typhuna ishikariensis is known as a serious obstacle. Although agricultural chemicals have conventionally been used as a principal measure for elimination of snow mold, danger of environmental pollution manifests itself as a problematic point. To solve the problem referred to above, a suspension of ultra-fine ferrite (200-300Å) was made paying attention to the behavior of an electromagnetic field. The suspension obtained in this manner was sprinkled at a ratio of 1g/m2 in the in room and on-the-spot tests, which made it possible to restrict the bacillus movement. On the other hand, concurrent employment of the suspension with agricultural chemicals made it possible to reduce the chemicals to the extent of almost 1/2 of the amount before the use. However the ferrite in a state of ultra-fine substances is so hard that the nozzle to be used for sprinkling the solution comes to be worn away, when a suspension is sprinkled. With a view to avoiding such trouble, the ultra-fine ferrite was mixed 1%-10% with a soil improvable materials. By agitating the said mixture, sprinkling becomes possible without any rectification. It is explained that sprinkling of the mixed solution in this manner helps restrict snow mold movement as with the case of suspension. Concurrently with this, it is also explained that growth of turf is promoted.抄録全体を表示PDF形式でダウンロード (8946K) -
田中 義和, 高須 一郎, 柳谷 彰彦2000 年 47 巻 2 号 p. 220-227
発行日: 2000/02/15
公開日: 2009/12/04
ジャーナル フリーMn-Al-C alloy is well known as a material for anisotropic magnets containing no expensive elements such as rare earth element or Co. The Mn-Al-C magnets show excellent performance in terms of high strength, good machinability, good corrosion resistance, etc. Mn-Al-C alloy magnet has been fabricated by the gas atomized powder extrusion process since 1989.
The magnetic properties of Mn-Al-C alloy extruded from gas atomized powder depend on the solidification rate of powder during atomization. Two exothermic peaks were observed at 760K and 820K by differential thermal analysis of gas atomized powder. Two exothermic peaks indicate that the ε→τ phase transformation occured in the different Mn content regions of ε phase. In this work, we investigated the phase transformation behaviors of gas atomized powder below 723K. It was found that in the first stage of ε→ τ transformation, ε→ε'→ τ transformation occurred with the activation energy of Q=277kJ/mole. The effects of Ni addition on ε→τ transformation were investigated between 673K and 723K. The activation energy was not affected by Ni addition, but small addition of Ni reduced the frequency factor.抄録全体を表示PDF形式でダウンロード (583K)
- |<
- <
- 1
- >
- >|