巻号一覧
66 巻, 8 号
選択された号の論文の7件中1～7を表示しています
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野口 邦広, 池田 真由美, 清水 勲, 大野 恭秀, 中森 孝2002 年 66 巻 8 号 p. 799-807
発行日: 2002年
公開日: 2008/04/24
ジャーナル フリーSn-37 mass%Pb and Sn-36 mass%Pb-2 mass%Ag solder balls have been bonded on Cu pads at the cooling rates of reflow. The microstructure and the mechanical properties of the ball bonding have been investigated. The eutectic lamellar structure (Sn phase/Pb phase) of both ball was finer. The lamellar spacing of Sn-36 mass%Pb-2 mass%Ag solder ball was much smaller than that of Sn-37 mass%Pb one at the faster cooling rates. The lamellar structure became finer since Ag may interrupt the diffusion of Sn and Pb. The ball hardness depended on the cooling rate and increased with the smaller lamellar spacing at the faster cooling rate. Since the eutectic Ag3Sn intermetallic compound formed in Sn-36 mass%Pb-2 mass%Ag solder ball, the hardness of this alloy ball was higher than that of Sn-37 mass%Pb one. The shear strength of both ball bonding dropped remarkably at 10 K/min since Ni3Sn4 reaction layer at the bonding interface was thicker. The shear strength of Sn-36 mass%Pb-2 mass%Ag ball was lower than that of Sn-37 mass%Pb one at each cooling rate. The primary needle-shape Ag3Sn was observed in Sn-36 mass%Pb-2 mass%Ag ball and near the bonding interface. The lower shear strength of Sn-36 mass%Pb-2 mass%Ag ball bonding was due to the primary needle-shape Ag3Sn near the bonding interface and the brittle Ni3Sn4 reaction layer. Since the fracture face of the Sn-36 mass%Pb-2 mass%Ag ball was flatter than that of the Sn-37 mass%Pb ball, the brittle fracture occurred at the Sn-36 mass%Pb-2 mass%Ag ball bonding interface.抄録全体を表示PDF形式でダウンロード (3202K) -
王 栄光, 森弘 尚希, 徳田 太郎, 木戸 光夫2002 年 66 巻 8 号 p. 808-815
発行日: 2002年
公開日: 2008/04/24
ジャーナル フリーThe distilled water macro- and micro-wetting morphologies on wet-polished, air-oxidized and distilled-water-immersed pure chromium, nickel, iron and SUS304 steel surfaces were observed with a digital microscope or an AC non-contact mode of atomic force microscope. The macro- and micro-wettabilities were measured from the obtained morphologies, and the relationship between them was examined. The influence of the surface chemical state on wettability was also examined.
Sample surface layers comprised pure metals (nickel, chromium or iron) and their oxides and hydroxides, and organic contaminants. Wettabilities differed for pure chromium, nickel, iron and SUS304 steel. Micro-wettability was higher than macro-wettability for all samples, but the dispersion of micro-wettabilities was large. Wettability was also dependent on different surface treatments such as wet polishing, air oxidation and water immersion.抄録全体を表示PDF形式でダウンロード (1160K) -
金長 政之, 井野 博満, 小田 克郎, 徳満 和人2002 年 66 巻 8 号 p. 816-823
発行日: 2002年
公開日: 2008/04/24
ジャーナル フリーThe aim of this study is to examine the relation between the stability of ferromagnetism and the atomic volume of FCC Fe-Cu-Au and Fe-Cu-Ni alloys prepared by mechanical alloying. From the measurements of X-ray diffraction, magnetization and Mössbauer effect, we concluded that the ferromagnetism of the FCC iron alloys is stabilized with increasing atomic volume of the alloys. The magnetic moment of iron increases with increasing atomic volume of the alloy up to 2.7μB. The trend is well consistent with that of the result of recent band calculation for FCC iron, which suggests that the local state density of iron in Fe-Cu-Au alloys is close to that of pure iron.抄録全体を表示PDF形式でダウンロード (615K) -
富田 俊郎2002 年 66 巻 8 号 p. 824-831
発行日: 2002年
公開日: 2008/04/24
ジャーナル フリーDecarburization of silicon steel sheets by silicon dioxide and texture development during the decarburization process have been investigated. Steel sheets with an approximated chemistry of 3%Si-1%Mn-0.05%C were stack-annealed with a SiO2-containing separator under a reduced pressure. During the anneal, C concentration of the sample markedly decreased, being caused by a thermo-chemical reaction between the steel and separator; 2C+SiO2→Si+2CO. Columnar α grains grew from the sheet surface, and therein an evolution of the {100}⟨012⟩ texture took place. An almost completely decarburized 0.35 mm thick sheet by this process consisted of grains of 0.6 mm in diameter, more than 90% of which well aligned to the {100}⟨012⟩ orientation. The decarburization reaction and the mechanism of the {100}⟨012⟩ texture evolution are discussed.抄録全体を表示PDF形式でダウンロード (999K) -
伊藤 勉, 石川 真之, 大塚 正久2002 年 66 巻 8 号 p. 832-839
発行日: 2002年
公開日: 2008/04/24
ジャーナル フリーHigh temperature tensile deformation behavior of Al-2 mol%Cu solid solution consisting of coarse and equiaxed grains has been investigated with a special reference to the occurrence of Class I superplasticity. Enhanced ductility up to about 260% is confirmed at the modulus compensated stress, σTS⁄E, below 1.6×10−4. The superplastic-like behavior should be attributed to a moderately strain rate sensitive deformation process which is governed by the solute drag of dislocations. The plastic instability or necking resistance is quantitatively discussed in relation to the strain rate sensitivity and work hardening rate. The role of grain boundary sliding is briefly described.抄録全体を表示PDF形式でダウンロード (930K) -
河口 恭寛, 山中 伸介2002 年 66 巻 8 号 p. 840-848
発行日: 2002年
公開日: 2008/04/24
ジャーナル フリーCast duplex stainless steel is frequently used in main coolant pipes of PWR (Pressurized water reactor) type nuclear power plants because of its excellent material strength, toughness and superior corrosion resistance. However, it is known that Cr concentration fluctuation in ferrite phase occurs due to thermal aging when this material is exposed to temperature over 300°C. As a result, the toughness decreases. In previous studies, it has been shown that thermoelectric power (TEP) is an effective parameter in non-destructive evaluation for thermal aging of cast duplex stainless steel. In this study, mechanisms of increase in TEP due to Cr concentration fluctuation caused by thermal aging were investigated. Referring to Cr concentration fluctuation in ferrite phase of thermal aged cast duplex stainless steel measured by 3D-atom prove, Fe-Cr-Ni alloys with different Cr concentrations, which represented local area Cr fluctuated, were prepared. Then, TEP, electrical conductivity and thermal conductivity of the alloys were measured, and the relationships between these values and Cr concentration were determined. Using the relationships and the Cr concentration fluctuations, TEP of thermal aged cast duplex steel were composed in the case when each Cr-fluctuated area acted in series connection and in parallel connection. Then, the changes in TEP due to thermal aging were simulated, and compared with that in experimentally measured TEP. As a result, recurrence curves of Cr concentration to TEP, electrical conductivity and thermal conductivity were downward convex parabolas. Therefore, it was found that, by means of creation of high and low Cr area in ferrite phase due to thermal aging, TEP, electrical conductivity and thermal conductivity of the whole material increased. When each Cr fluctuated area acted in parallel connections, increase in TEP due to thermal aging became larger and the change in the composed TEP came close to that in the experimentally measured TEP.抄録全体を表示PDF形式でダウンロード (1393K) -
日比野 敦2002 年 66 巻 8 号 p. 849-855
発行日: 2002年
公開日: 2008/04/24
ジャーナル フリーTo produce TiAl intermetallic compounds, a combustion synthesis was attempted with a sintering additive of Co/Al. Mechanical properties of the combustion synthesized products were examined in the range of Ti/Al ratio from 0.43 to 2.33. The measurements of density, phases, microstructure, and size accuracy of the products revealed that a good performance with high density and fine micro structures was obtainable when the Ti/Al ratio was in the range from 1.0 to 1.22. Effect of the quantity of Co/Al additive on the density of the products was also examined.抄録全体を表示PDF形式でダウンロード (1550K)
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