材料
Online ISSN : 1880-7488
Print ISSN : 0514-5163
ISSN-L : 0514-5163
58 巻 , 10 号
選択された号の論文の15件中1~15を表示しています
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論文
  • 塩澤 大輝, 藤本 高志, 有野 直樹, 中井 善一
    2009 年 58 巻 10 号 p. 808-814
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    SQUID (Superconducting Quantum Interface Device) has high magnetic sensitivity and high magnetic resolution. In this study, high-temperature SQUID microscope was applied to the detection of defects in printed wire. SQUID microscope with high permeability needle (flux guide) showed high spatial resolution measurement of the sample in air at room temperature. The distribution of magnetic field around printed wires that subjected to DC current was measured. The results of measuring magnetic field for 0.7mm line and spacing meander lines showed the effect of flux guide on spatial resolution improvement. The distribution of magnetic field around the printed wire with defects has been analyzed numerically. It was found that the magnetic field distribution and magnetic field gradient showed that changes according to the parameters of defect such as defect width and location. SQUID microscope was applied to inspect the imperfections in the width and thickness of the printed wire. It was found from these measurements that the SQUID microscope could measure the changes in magnetic field distribution induced by the imperfection in the width and thickness. The shape of measured magnetic field distribution for printed wire having the defect in width was similar to that of calculated distribution. Defect in small sized wires with the width of 200μm also could be detected by the measured magnetic field gradient distribution.
  • 上辻 靖智, 小川 良太, 倉前 宏行, 槌谷 和義
    2009 年 58 巻 10 号 p. 815-820
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    A material properties estimation method was proposed for piezoelectric thin films fabricated on substrates. The proposed method can present piezoelectric strain constant d333 on basis of displacement difference between top and bottom points of specimen under external electric field with a disc-type electrode. In this paper, its availability was verified with finite element method. Thicknesses of piezoelectric thin film and substrate were changed and the mechanical and electrical behavior was computationally analyzed to get dual-points concurrent displacement. Then piezoelectric strain constant was estimated from the simultaneous equation in consideration of piezoelectric and Poisson's effects. As a result, the errors of the estimated values under static and dynamic electric fields were 1.1 % and 4.1%, respectively.
  • 秦 誠一, 藤田 敏充, 桜井 淳平, 下河辺 明
    2009 年 58 巻 10 号 p. 821-826
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    This paper describes a combinatorial deposition method using single arc plasma gun (APG). Previously there is combinatorial arc plasma deposition (CAPD) which uses three APGs by turns to deposit a composition grade thin film. In this research, in order to make this CAPD more simply and compact, deposition of composition grade thin film was tried by single APG using alloy cathode. As the results, using the alloy cathode of Pd-Si with which an atomic weight differs about three times, the almost constant compositionally-graded thin film of 14.2 to 85.5 at.% was obtained. On the other hand, in the alloy cathode of Cu-Zn in which an atomic weight is almost same, the compositionally-graded thin film of 59.7 to 81.1 at.% was obtained. It was about 5% of composition grade in large region. It is possible to deposit a compositionally-graded thin film by single APG using alloy cathode which have greatly different atomic weight. The principle of the deposition for compositionally-graded thin film is similar to mass spectrometry.
  • 鄭 聖哲, 村田 直一, 佐藤 祐規, 鈴木 研, 三浦 英生
    2009 年 58 巻 10 号 p. 827-832
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    Mechanical and electrical reliability of fine bumps with diameter and height of tens of μm was studied considering the growth of the intermetallic compound (IMC) at the interface between a bump and a copper thin-film interconnection. It was found that the increase of the thickness of the IMC change the stress and strain field around the interface significantly, and thus, the fracture mode from the fatigue crack of solder to fatigue crack of the copper interconnection or delamination between the IMC and the copper interconnection. This is because that the mechanical properties of the grown IMC differ from those of copper and tin and that a large amount of Kirkendall voids appeared around the interface. In addition, the resistance of the bumps increased drastically with the increment of the thickness of the IMC layer because of the growth of Kirkendall voids. Therefore, it is very important to minimize the growth of the IMC to assure the reliability of the bump joint structures.
  • 中山 朝之, 坂上 賢一, 小川 武史, 小林 圭史, 寺谷 武馬
    2009 年 58 巻 10 号 p. 833-840
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    This paper discussed the fracture mechanism of diamond like carbon (DLC) film subjected to contact loading. The DLC films with the thickness of about 12μm were deposited onto SUS304, SUS410 and WC-Co substrates by radio frequency (RF) plasma-based ion implantation method. Dual indenter method was applied to determine the stress-strain response of the films. Rockwell indentation tests with simultaneous monitoring of acoustic emission (AE) and corrosion potential fluctuation (CPF) techniques were also applied to the films to evaluate the static tensile strength. FEM analyses demonstrated the stress distribution under indentation testing and correlated the film fracture behavior with static strength of the films, which was assumed to be independent of the substrate materials based on the results of Raman spectra and indentation tests. Cyclic indentation tests were performed on the DLC film deposited onto WC-Co in order to evaluate the fatigue strength of the film. The cyclic fatigue was found to degrade the film strength compared to the static property.
  • 津志田 雅之, 坂元 隆宏, 北原 弘基, 安藤 新二
    2009 年 58 巻 10 号 p. 841-846
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    To investigate fatigue fracture behavior of small titanium single crystals, plain bending fatigue test method for thin sheet specimens was developed. One end of the sheet specimen was fixed at a voice coil of a loudspeaker and the other end was set free. A bending mode resonance occurs in the specimen due to forced vibration at the fixed end. In A-specimen whose surface plane and loading direction were (0001) and [1120], the fatigue crack propagated parallel to {1100} plane and striation-like markings were observed on the fatigue fracture surfaces. In B-specimen with (0001) surface and [1100] loading direction, the fatigue crack also propagated parallel to {1100} plane as similar to A-specimen. These fatigue cracks are deduced to extend by alternating shear on two intersecting prismatic slip systems at the crack tip. In D-specimen with (1100) surface and [1120] loading direction, the fatigue crack propagated along [0001] with prismatic slip. In E- and F-specimen with [0001] loading direction, these fatigue cracks propagated parallel to (0001) with {1012} twinning. As a result, S-N plots of each specimen showed strong orientation dependence.
  • 燈明 泰成, 武田 大尚, アカンダ モハマド アブドゥス サラム
    2009 年 58 巻 10 号 p. 847-851
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    In this paper, the manipulation technique for very-thin metallic wires based on Joule heat joining is reported. Our basic idea is to weld the objective thin wires on substrate material, which can easily be manipulated. Thick In wires were selected as substrates, and very-thin Pt wires with the diameter of 650 nm were welded onto In wire substrate by Joule heating. The Pt wire on the In substrate was undertaken for small-span bending test and the mechanical properties, especially Young's modulus and the yield strength of the wire were successfully determined. For electrical properties, the electrical circuits including the thin Pt wire were fabricated on an electrode chip, and the potential drops using two Ag probes for various probe distances were measured. The electrical resistivity of the Pt wire was successfully evaluated from the measured potential drop data.
論文
  • 種子島 亮太, 城阪 哲哉, 曙 紘之, 加藤 昌彦, 菅田 淳, 箕島 弘二
    2009 年 58 巻 10 号 p. 853-859
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    In this study, fatigue properties of PM (Powder Metallurgy) soft magnetic materials were investigated by observation of the small fatigue crack propagation. The materials to which binder resin were added (Material BA) and three kinds of materials with different density (Material LD, MD and HD) were used in this study. Reversed plane bending fatigue tests were conducted at room temperature and small fatigue crack growths were studied in detail by means of replication technique. The fatigue strength became higher in the order, material HD, MD, LD, BA. In all specimens, cracks initiated at multi sites and each crack propagated with frequent deflection. Furthermore, cracks were coalesced repeatedly and specimen reached final fracture. Moreover, the difference between the materials was not recognized clearly in the da/dN-Kmax relationship. The maximum defect size, √area max, which was estimated by the statistics of extreme value became higher in the order, material BA, LD, MD, HD. As a result, the addition of the binder resin to PM alloy was not effective in improvement of fatigue strength. Furthermore, densification by increasing compacting pressure was effective in improvement of fatigue strength because the maximum defect size in each material became smaller. The ΔK0-Nf/√area max was estimated to consider whether the evaluation by the statistics of extreme value had propriety to the fatigue strength. Then, their curves were not corresponded. The disagreement was originated in the difference of coalescence frequency until the specimen reached to final fracture.
  • 皮籠石 紀雄, 金丸 智紀, 仮屋 孝二, 大園 義久
    2009 年 58 巻 10 号 p. 860-864
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    In order to investigate the effect of humidity on fatigue strength of an extruded and age-hardened Al alloy 7075-T6, rotating bending fatigue tests were carried out using plain specimens and circumferential notched ones with notch radii of 1.0, 0.1 and 0.05mm in environments of relative humidity 25% and 85%. Fatigue strength was decreased by high humidity, except for notched specimen with notch radius of 0.1mm. Fatigue limit for notched specimen with notch radius of 0.05mm was very high in low humidity. Notch sensitivity for crack initiation was low and the one for crack propagation was reversely high in high humidity. Branch points were 0.05-0.1mm in low humidity and about 0.3mm in high one, respectively. Crack in sharply notched specimen tended to propagate in shear mode in low humidity with decreases in stress level, though all of crack propagations were in tensile mode in high humidity. This was a main reason for high fatigue limit in notched specimen with notch radius of 0.05mm in low humidity.
再録論文
  • English version of the paper published in “Journal of the Society of Materials
    Science, Japan, 57 (9) : 921-928 (2008)”
    Sei MIURA, Nagato ONO, Yoshito NISHIMURA
    2009 年 58 巻 10 号 p. 865-872
    発行日: 2009/10/15
    公開日: 2009/10/21
    ジャーナル フリー
    The present work has investigated whether the twin boundaries are to be included or not in the Hall-Petch equation for polycrystalline metals. Pure copper, Cu-3.5at%Al, Cu-6.8at%Al and Cu-14.8at%Al alloys, which have the average grain sizes from 8.4 to 176.0μm and the different ratio of annealing twins, were produced and pulled in tension at temperatures from 77 to 973K under a strain rate of 1.2 × 10-4s-1. The distribution of dislocations in the surface grains was also observed by using the etch pit technique. 0.1% proof stress including the twins for each specimen at room temperature conforms well to the Hall-Petch relation. The halves of intersecting stress σ0 derived from the straight lines are approximately equal to the critical resolved shear stress of each single crystal, i. e. CRSS, so far reported. It is found that the proportional relation between the σ0/2 value and the square root of aluminum concentration is in good agreement for the single crystals and the polycrystalline specimens. The temperature dependence on the σ0/2 values for Cu-14.8at%Al alloys is similar to the variations for the CRSS of single crystals, especially at the region of low and elevated temperatures. From the Hall-Petch parameters at 293K, the unlocking stress of edge dislocations from the solute atoms is found to be 3.5 times larger than the CRSS of single crystals. This CRSS is thought to be the unlocking stress of screw dislocations which come out onto the crystal surface. It is considered that the role of the twin boundaries is almost equivalent to the grain boundaries, because the multiplicative dislocations pile up against the twin and grain boundaries during the small deformation.
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