巻号一覧
42 巻, 12 号
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平井 敏雄1995 年 42 巻 12 号 p. 1360
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーPDF形式でダウンロード (67K) -
丹野 浩一, 工藤 育美, 後迫 勉1995 年 42 巻 12 号 p. 1361-1366
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーA novel technique for fabricating functionally graded materials (FGMs) of stainless steel/zirconia system has been developed. Composite particles coated with 3Y-PSZ powder on SUS316L particles were used as starting powders. The designing of the gradational distribution of SUS316L and 3Y-PSZ was achieved by adding vibration to stacked powder beds of composite particles with differential blending ratio(from10wt.%-90wt.% in10%steps)respectively. The interface of several stacked layers of differential coating ratio became indistinct by the powder technological filter effect which occured by the vibration. The structure and the compositional gradient of FGM block were examined by OM, SEM, EPMA, X-ray analyses. And the properties of the FGM block such as density, hardness, heat resistant were measured. The FGMs of the SUS316L/3Y-PSZ system without a visible crack-like discontinuity throughout in the overall cross section were accomplished by the vibrational frequency in 50Hz, amplitude of 0.35-0.5mm and sintered at 1353K for 7.2ks, at the pressure of 19.6MPa in Ar gas atmosphere.抄録全体を表示PDF形式でダウンロード (8478K) -
三宅 大輔, 戸丸 秀和, 高木 智史, 川崎 亮, 渡辺 龍三1995 年 42 巻 12 号 p. 1367-1372
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーMolybdenum/stainless steel/titanium functionally graded materials (FGM), which will be used as long lire cladding tubes in a fast breeder reactor, have been fabricated by slurry dipping and sintering process, emphasizing the increase in corrosion resistance to liquid sodium and fission products. Slurries of different composi-tions were prepared by mixing the appropriate amount of Mo, SUS304 and Ti powders in water with polyvinyl alcohol. Cylindrical substrates were formed by die pressing of stainless steel and alumina powders. The sub-strates were dipped in the slurry to coat the surface subsequently dried in air and debinded in Ar. They were encapsulated in Pyrex glass tubes and then HIPed 2h at 1050°C at a pressure of 200MPa.The microstructural observation in the cross section of the sintered compacts has revealed that the dipped layers were formed, in which no defects such as small cracks and residual pores were observed. Some intermetallic compounds were observed in the FGM layer as detected by EPMA.抄録全体を表示PDF形式でダウンロード (2894K) -
新谷 光二, 畠中 裕次1995 年 42 巻 12 号 p. 1373-1378
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーWe placed a Ni-metal foil between two MgO blocks, and annealed this set in air. The Ni-metal foil entirely reacted with gaseous oxygen to NiO. Thus, we accomplished the joining of two MgO blocks to form MgO-NiO solid solution at the joining part. This technique is highly suitable to weld ceramics into one body with a solely continuous interface. It will be also of great help in forming ceramic products into a complicated or very long shape. We examined the joining, using a nickel foil 10 or 50 pm thick, at 1573-1873K for 176.4-1440ks. The joining layer consisted of the functionally gradient material of MgO-NiO system. The fracture strength of joints annealed at 1573K was very low value, but, those of the joints annealed at 1873K ranged from 40MPa to 95MPa and average value reached about 70% of the strength of the MgO samples. About the penetration curves of the MgO-NiO system, assuming quasi-binary system, and by plane source method, we could obtain the chemical diffusion coefficient, D of 3.3x10-15m2s-1 at 1573K.抄録全体を表示PDF形式でダウンロード (8956K) -
湯浅 栄二, 師岡 利政, 村里 紀英1995 年 42 巻 12 号 p. 1379-1383
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーTitanium and boron powders having a molar ratio of Ti/B=1/2 were mixed to copper powder with compositions as Cu-5mol%Ti-10mol%B and Cu-9mol%Ti-18mol%B. They were mechanically alloyed for various milling times by using ball mill. The powders of two different compositions were compacted and bonded to each other. They were sintered at the temperature range of 873K to 1173K for various times. Diffusion of copper and titanium atoms progresses at the interface of the bonded compact by the sintering at high temperature for prolonged time. Thickness of the diffusion layer in the bonded compact which prepared from the powder mechanically alloyed for long milling time becomes more wide than that prepared from the powder mechanically alloyed for short milling time. Rupture strength obtained in the 3-point-bending test of the bonded compact is increased by the sintering. But, the degree of increment of the rupture strength in the sintered compact which prepared from the mechanically alloyed powder decreases with the increase of mechanical alloying time.抄録全体を表示PDF形式でダウンロード (3020K) -
Mamoru Omori, Hirotaka Sakai, Katsuhiro Nishiyama, Eiji Suzuki, Toshio ...1995 年 42 巻 12 号 p. 1384-1388
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーDense FGMs were fabricated from ZrO2(3Y) and metals (Ni and stainless steel) by spark plasma sintering. These FGMs exhibited two kinds of residual stress (a local stress and a layer stress), local stress is stored in each layer, while layer stress is dispersed throughout each layer of the whole FGM. The local stress was estimated by measuring Vickers hardness.抄録全体を表示PDF形式でダウンロード (249K) -
森口 秀樹, 池ケ谷 明彦, 野村 俊雄, 宮本 欽生, 栗 振思, 谷畑 公昭1995 年 42 巻 12 号 p. 1389-1393
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーAl2O3-TiC ceramic tools are used for finish machining of cast iron. But these tools break easily in wet cutting. In order to overcome this problem, the cutting performance of hyperfunctional Al2O3-TiC ceramic tools with symmetrically graded structures of Al2O3/TiC/Ni/TiCAl2O3 were studied. Two hyperfunctional ceramic tools with different types of layering were fabricated by SHS/HIP processes. Al2O3-TiC ceramic tools with symmetrically graded structure of concentric layers showed good breakage resistance in wet cutting as compared with monolithic Al2O3-TiC ceramic tools fabricated using the same process. Numerical calculation using the finite element method (FEM) showed that the Al2O3-TiC ceramic tools with the symmetrically graded structure of concentric layers had strong residual compressive stress at the edge of the tool in the direction parallel to the edge. It seemed that this compressive stress was effective in preventing breakage.抄録全体を表示PDF形式でダウンロード (2973K) -
向田 行宏, 藤原 昭宏, 川崎 亮, 李 敬鋒, 渡辺 龍三1995 年 42 巻 12 号 p. 1394-1399
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーThe burner heating test was carried out for evaluating the thermomechanical performance of SiC-A1N/Mo Functionally Graded Materials (FGMs) fabricated by powder metallurgical process. The ceramic surface was heated with burner flame and the bottom surface cooled by water flow. The top and bottom surface tempera-tures and the average heat flux were determined as a function of the power output of burner. Thermal shock damage was monitored with acoustic emission signals liberated from damage initiation and propagation. By increasing the output power of burner stepwisely, a cycle of heating and cooling was repeated until a large damage was detected. The holders made of Ti and Cu were prepared as cooling substrates so as to investigate the influence of the material of the holders on thermal shock damage. The Ti holder was found to contribute the increase of the heat insulating efficiency with effective black radiation from the top surface, which increases remarkably with increase in the surface temperature. The thermal shock damage of the specimen mounted on the Ti holder was observed on the ceramic surface during cooling. The mechanism for this damage formation was found to be very similar to the case of PSZJStainless steel functionally graded materials.抄録全体を表示PDF形式でダウンロード (3993K) -
山田 葉子, 渡辺 龍三, 江 莞1995 年 42 巻 12 号 p. 1400-1405
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーThe effect of fiber orientation on the thermal expansion coefficient, the Young's modulus and the thermal conductivity of hot pressed Mo/PSZ composites was studied both experimentally and theoretically. The fiber orientation of the hot pressed Mo/PSZ composites was determined by optical microscopic observations on their cross-sections. In order to make a theoretical analysis of the above mentioned properties on the basis of Eshelby's equivalent inclusion method, the measured fiber orientation distributions were converted to polynomial functions. Compared with the conventional procedure using cosine or uniform distribution functions for the fiber orientation, the polynomial distribution function gave predictions which were in good agreement with the experimental.抄録全体を表示PDF形式でダウンロード (427K) -
後藤 孝, 李 剣輝, 平井 敏雄1995 年 42 巻 12 号 p. 1406-1410
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーW-B-C system composites were prepared by arc melting in an argon atmosphere using B4C, WC, WB, B and C powders. Lamella textures indicating eutectic reaction were observed at B4C contents of about 20mo1% and l0mol% in the quasi-binary W2B5-B4C and WB4-B4C systems, respectively. Carbon phase in the W2B-B4C-C ternary system was needle-like. The Seebeck coefficient (α) generally decreased with increasing W2B5 and WB4 contents. However, the W2B5-B4C composites containing 2mol%W2B5 have slightly greater α values than those of B4C in the temperatures range between 200 and 1000K. The electrical (σ) and thermal conductivities (K) increase with increasing W2B5 and WB4 contents. The figure of merit values (Z) increased with increasing temperature. The W2B5-B4C composites containing 2mol%W2B5 showed slightly greater Z values than B4C at temperatures between 200 and 1000K. The highest ZT value at T=1000K was about 0.1.抄録全体を表示PDF形式でダウンロード (2959K) -
賀集 誠一郎, 美原 康雄, 林 主税, 佐藤 昌敏, 飯島 正行1995 年 42 巻 12 号 p. 1411-1414
発行日: 1995/12/15
公開日: 2009/12/04
ジャーナル フリーPolyurea films of 0.1 to 0.3 μ m in thickness with vapor deposition polymerization system have been laminated on PZT deposited films of 1 to 4 μm in thickness with aerosol jet printing system. This structure of the laminated film has been tested in order to increase its electrostatic capacity without reducing breakdown voltage. By SEM observation, the surface of PZT film with roughness of submicron level has been closely covered by polyurea thin film. Electrostatic capacity of laminated film is several tens percent higher than that of polyurea thin film only. It is caused by increase of surface area owing to roughness of the surface of PZT film. Dielectric loss tangents of laminated films at 1kHz were measured and showed constant value independently of their film thickness. By change of the thickness of PZT films and polyurea thin films, electrostatic capacity and breakdown voltage can be controlled.抄録全体を表示PDF形式でダウンロード (1370K) -
新子 貴史, 岸本 章, 中塚 勝人1995 年 42 巻 12 号 p. 1415-1420
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーMulti-layer composed of silica and titania alternately was formed on the surface of the iron powder. The powder dispersed in the ethanol solution containing ethoxide, and each layer was formed by using hydrolysis of the ethoxide.
Inteference of the visible light of the mono- or multi-layer coated powder was measured as a wave pattern by using the monochrometer.
The wavelength of the peaks and the bottoms of the wave pattern of interference of the multi-layer coated powder were controled by the composition of each coating solution.
Each wavelength of the peak and the bottom of wave pattern of the inteference of the multi-layer coated powder was nearly same as the simulated value.抄録全体を表示PDF形式でダウンロード (3961K) -
落合 鍾一, 山崎 道夫, 村上 雄, 宗宮 重行1995 年 42 巻 12 号 p. 1423-1429
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーNi3Al matrix composite alloys with 0, 20, 40, 60 and 80vol%TiC particles were produced by mechanical alloying - hot press process using pure Ni, pure Al and TiC powders. Morphological change of powders during mechanical alloying process was studied. Also, the microstructures and the mechanical properties as well as the oxidation properties of sintered specimens were investigated. Fine powders with diameter of less than 10μm were produced by mechanical alloying. Sintered composite alloys were found that they consist of Ni3Al matrix with small amount of γ phase and uniformly dispersed TiC particles. Although the plastic strain was observed for the 0- 40vol%TiC alloys at any temperature investigated, 60 and 80vol%TiC alloys deformed plastically only at higher temperatures than 673K and 1073K, respectively. The flow stresses for alloys with 0-40vol%TiC exhibited the plateau region from 400K to 700K, and then decreased markedly. It was revealed that the strain rate sensitivity exponent (m value) for the base matrix alloy was over 0.4, indicating the development of superplastic deformation. Mass gain during oxidation test at 1273K increased with TiC volume fraction.抄録全体を表示PDF形式でダウンロード (5700K) -
高田 仁輔, 河合 伸泰1995 年 42 巻 12 号 p. 1430-1436
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーThe effect of sulfur on the dimensional change during sintering was examined by using two different water-atomized iron powder groups with about 0.01 and 0.3mass% sulfur. The compacts of Fe-2mass%Cu-0.8mass%C-0.75 mass% zinc sterate were sintered in endogas and those of the Fe-C system were sintered in Hz and Ar to investigate the mechanism.
In endogas in the case of the high sulfur powder, the suppression of the carburization by the atmosphere occurred in the α-Fe region and that by graphite occurred in γ-Fe, and the copper growth increased leading to more expansion during sintering. The suppression of the carburization also occurred in H2 and Ar in the case of the high sulfur powder, whereas it occurred only in Ar in the case of the low sulfur powder. By sintering Fe-C compacts containing excess graphite in Ar, it was found that the carbon solubility in γ-Fe decreased with increasing sulfur content in iron powder.
The addition of FeS to the low sulfur powder brought about the suppression of the carburization and an extreme expansion in comparison with MnS. The mechanism was discussed from the view of thermodynamics.抄録全体を表示PDF形式でダウンロード (466K) -
朝日 信夫, 牧 哲生1995 年 42 巻 12 号 p. 1437-1440
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーAl65Cu20Fe15 mixed powder was mechanically alloyed using a planetary ball mill (Fritsch P-7) with the intensity setting at 7 in an Ar atmosphere. The alloying process was investigated by X-ray diffractometry, differential scanning calorimetry and electron microscopy. Mackay type icosahedral phase (i-phase) quasicrystal with primitive sixdimensional hypercubic lattice (P-type) was obtained directly by mechanically alloying (MA) in powders milled for 15 and 20h. It was found that the i-phase quasicrystal with the P-type was transformed into the i-phase with the face-centred six-dimensional hypercubic lattice (F-type) on heating to the temperature range from 900 to 1100K. In powders milled for 5 and 10h, the formation of the quasicrystalline alloy could not be observed during MA, but the i-phase quasicrystal with the F-type was obtained indirectly after additional heating.抄録全体を表示PDF形式でダウンロード (1161K) -
神津 典之, 林 慎太郎, 真渕 徳之, 田中 喜佳, 井口 喜章, 岸 弘志1995 年 42 巻 12 号 p. 1441-1445
発行日: 1995/12/15
公開日: 2009/12/04
ジャーナル フリーIn order to control the grain size of semiconductive SrTiO3 ceramics, the effects of calcination condition and Sr/Ti ratio on the sintering process of this compound has been investigated. The particle size of calcined powder increases substantially with increase of calcining temperature in the Sr/Ti ratio ranging from 0.993 to 0.999, which suggests that the Sr/Ti ratio plays an important roll in particle size growth. It has been confirmed that the grain size of sintered body is controlled by particle size of calcined powder.抄録全体を表示PDF形式でダウンロード (4406K) -
Nobuhiro Tsujii, Daien Yokoi, Kenzo Fukaura, Hisakichi Sunada1995 年 42 巻 12 号 p. 1446-1451
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーEffects of the quenching temperature on the mechanical properties at room temperature of two kinds of P/M hot work tool steels, AISI Hll standard grade and a newly developed grade, were investigated in comparison with conventional materials produced by ingot metallurgy. The tensile strength increased and the impact energy decreased with increasing the quenching temperature. However, the impact energy of P/M materials quenched from 1403K were much higher than that of I/M materials. It was found from the results of instrumented Charpy impact tests that the approximately 80% of impact energy was exhausted for crack initiation. The impact fracture modes at the root of the notch were divided into three groups as follows: 1) ductile fracture paralleled to the direction of maximum shear stress, 2) ductile fracture with stretched zone and 3) brittle intergranular fracture. It was also found that the anisotropy impact energy in P/M materials quenched from 1303K resulted from broken stringer inclusions of SiO2.抄録全体を表示PDF形式でダウンロード (4064K) -
李 敬鋒, 浅野 峰生, 小林 義政, 川崎 亮, 渡辺 龍三1995 年 42 巻 12 号 p. 1452-1456
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーThe pressureless-sintering behavior of AIN-SiC ceramics with 2mass% Y2O3 as a sintering aid was investigated. The AIN-SiC composites containing up to 30vol% SiC (two kinds of SiC sources: equiaxed α-SiC and rod-shaped β-SiC particles) were sintered to about 97% of the theoretical density at 2073K in Ar atmosphere of 0.1MPa, and fully densified further by cladless post-HIP-sintering. The mechanical properties including Young's modulus, bending strength and fracture toughness were evaluated for the densely HIPed materials. The Young's modulus was measured from room temperature to 1723K, and the AIN and AIN-SiC composites showed no decrease in Young's modulus at temperatures up to 1473K. The AIN-SiC composites showed increasing bending strength with increasing SiC content, and the highest bending strength was obtained in the AIN-30%SiC composite with rod-shaped β-SiC particles. The fracture toughness of the AIN increased about 60% after the post-HIP treatment due to the toughening effect of elongated grains which was found to be preferably formed in the AIN and AIN-rich composites. The AIN-SiC composites showed no remarkable increase in the fracture toughness with increasing SiC additions, as a result of the decrease in the amount of the elongated grains.抄録全体を表示PDF形式でダウンロード (1674K) -
西村 聡之, 三友 護, 廣津留 秀樹1995 年 42 巻 12 号 p. 1457-1462
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーEffect of particle size of raw powder on the sintering and grain growth of silicon nitride ceramics was invesitigated. β -silicon nitride powder, which is stable at high temperature, was used to eliminate the effect of phase transformation. Fine powder was made from commercial submicrometer powder by removing particles of over 0.5μm in diameter using grinding and centrifugal sedimentation. The fine and submicrometer powders were sintered by hot-pressing. Fine-grained silicon nitride ceramics was fabricated from the fine powder. This fine grained ceramics deformed at a strain rate of 1.8×10-4/s under 1500°C and 40 MPa of compressive stress, i.e. it had superplasticity. Microstructure of the fine-grained ceramics was stable on annealing at 1800°C for lh. The grain growth rate during hot-pressing and annealing of submicrometer powder was larger than that in fine powder. It was revealed that the difference in grain size is a main driving force for the grain growth. Fine and homogeneous particle size distribution of raw powder is necessary to fabricate superplastic silicon nitride ceramics.抄録全体を表示PDF形式でダウンロード (6162K) -
廣瀬 徳豊, 寒川 喜光, 浅見 淳一1995 年 42 巻 12 号 p. 1463-1467
発行日: 1995/12/15
公開日: 2009/05/22
ジャーナル フリーIn order to study the effect of injection speed on distribution of metal powder for the metal injection molding (MIM), we observed the specimens, MIMed at injection speed of 10%, 30%, 70% and 90% against maximum speed, by using an acoustic microscope. We compared acoustic images with back scattering electron images of the MIMed specimen, and found that the acoustic images can show distribution of metal powders.
As the results of observation on the acoustic images, difference of distribution of metal powders on specimen MIMed at each injection speed could he distinguished. On the acoustic images of the specimen MIMed at 10% injection speed, especially, irregular distribution of metal powders and flow marks were clearly observed at a position remote from the molding gate of the specimen. And at 90%, jetting was observed. Therefore, in the case of compound and injection condition used in this study, the obtained results showed that 10% injection speed is too slow and 90% is too fast to make sound MIMed specimens.抄録全体を表示PDF形式でダウンロード (6392K) -
村岡 芳幸, 吉川 文人, 廣田 健, 山口 修1995 年 42 巻 12 号 p. 1468-1472
発行日: 1995/12/15
公開日: 2010/11/19
ジャーナル フリーDense sintered materials (>99% of theoretical) consisting of three-layer structures with the compositions of ZrO2(2Y)/MOSi2=(60/40:A)/(80/20:B)/(60/40:A) mol% have been able to be fabricated by hot isostatic pressing at 1400°C for 2 h under 196 MPa. The materials show an anisotropy in overall electric resistivities measured in the perpendicular and parallel directions for the laminated interfaces: the former and latter resistivities correspond to insulating (ρ⊥≈1×1011Ω⋅cm) and metallic (ρ _??_ ≈1×10-4 Ω⋅cm) materials, respectively. The fracture toughness (KIc) is much affected by the residual stress estimated to be as much as ≈150 MPa at the interfaces. The residual stress acts as compressive and tensile stresses in the layers A and B, respectively.抄録全体を表示PDF形式でダウンロード (2106K)
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