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Published: August 02, 2008
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Article type: Appendix
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Article type: Appendix
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Article type: Index
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A1-A7
Published: August 02, 2008
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Yoshihiro OCHIAI
Article type: Article
Session ID: 611
Published: August 02, 2008
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The conventional boundary element method (BEM) needs a domain integral in heat conduction analysis with heat generation or initial temperature distribution. This paper shows that the three-dimensional heat conduction problem can be solved effectively by using the triple-reciprocity boundary element method without internal cells. In this method, the distribution of heat generation and initial temperature are interpolated by using integral equations. In this method, time-dependant fundamental solutions are used. A new computer program was developed and applied to solving several problems.
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Yuzuru EGUCHI
Article type: Article
Session ID: 612
Published: August 02, 2008
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The SPR (Superconvergent Patch Recovery) method proposed by Zienkiewicz and Zhu (1992) is incorporated in the time integration process of the dynamic plane shell equation. The SPR method is employed to compute the second-order spatial differentiations such as Laplacian of displacement, and to evaluate the restoration force due to flexural rigidity. The defects of rank deficiency of an SPR matrix and hourglass mode instability are overcome by remedies proposed by Yue and Robbins Jr. (2007), and Flanagan and Belytschko (1981), respectively. The proposed numerical method is validated with comparison of the theoretical and numerical results of a free vibration of a circular disk.
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Daisuke HARADA, Shigeru MURATA, Katsuyuki TSUJI
Article type: Article
Session ID: 613
Published: August 02, 2008
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This paper presents a phase-shifting digital holographic method for measuring dynamic phenomenon of fluid flow in three dimensional space. Phase-shifting digital holography usually needs three or four holograms, but the present method uses two holograms captured with a frame straddling technique. Object images are reconstructed from the information of phase-adjusted light amplitude. The measurement accuracy of the present method is evaluated by numerical simulation in comparison with other phase-shifting techniques.
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Hiroshi OKADA, Hiroshi KAWAI
Article type: Article
Session ID: 614
Published: August 02, 2008
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In this paper, the development of a fully automated computational mechanics analysis system for three-dimensional (fatigue) crack propagation problems is described. The finite element analyses for the cracked bodies are performed by using the second-order tetrahedral finite element. The stress intensity factors are computed by using the virtual crack closure-integral method that was extended to the case of tetrahedral finite element by the authors. Analyses models for the cracked structures are generated by using an automatic mesh generation scheme that was also proposed by the authors. The finite element analyses are performed by using the ADVENTURE system and its associated modules are utilized to handle data in large-scale crack analyses. The analysis system is briefly described and a demonstration problem is shown in this paper.
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Tadao FUKUTA, Yasuhiro AKAHOSHI, Yuki TAKAYAMA, Koichi OZAKI
Article type: Article
Session ID: 615
Published: August 02, 2008
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At present, the demand to the improvement in the characteristic of steel material is expanded in the various directions with development of industrial technology, and investigation of the improvement is performed. We focus on precipitation hardening in strengthening mechanism of steel materials. In this study, we simulate an influence of copper precipitates on motion of an edge dislocation using Molecular Dynamics (MD) method in the iron-copper model alloys. In this paper, we compare the motion of the dislocation between copper cluster of 3nm and solution cluster, and discuss their difference.
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Keisuke KUBOTA, Ken-ichi SAITOH, Tomohiro SATOH, Noboru SHINKE
Article type: Article
Session ID: 616
Published: August 02, 2008
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The mechanism of stress-induced amorphization and martensite transformation is analyzed at an atomic level by using molecular dynamics (MD). Calculation model for MD is made of Ni-Ti (B2 structure) alloy which has edge cracking. The framework of modified embedded atom method (MEAM) potential and its approximated expression are attempted to be adopted in order to reproduce amorphous structure. The pentagonal bipyramid which is used as one of noncrystalline models is focused on, and short-range order of amorphous is distinguished by detecting indices of (1551) and (1541) for bond pairs defined in CNA. Martensite phase (B19' structure) is distinguished by the analysis of lattice constants of primitive crystal unit. As a result, it is found that amorphous structure has concentrated on nearby crack. The change of shear component in stress tensor shows very similar trend for change of amorphization ratio defined here. On the other hand, the results show that tensile stress plays an important role in martensite transformation.
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Akinori FUKUSHIMA, Masato SENAMI, Akitomo TACHIBANA
Article type: Article
Session ID: 617
Published: August 02, 2008
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We studied Al and AlB nanowires as hydrogen storage materials based on density functional theory. In this work, we focused on the electronic structure of models for these nanowires. AlB nanowire models are compared with an Al nanowire model in terms of band structures and electron density. The band structure of AlB nanowire is semi-conductive, and that of Al nanowire is metallic. In addition, the electron density of the highest occupied band in AlB nanowire is localized on the B atoms, but in the case of Al nanowire, the electron density is not localized on specific atoms. These results revealed that AlB nanowires do not have the conductivity and the Al nanowire has it.
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Ryota ENISHI, Tadashige IKEDA, Tetsuhiko UEDA
Article type: Article
Session ID: 1001
Published: August 02, 2008
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A micromechanical phase transformation model of shape memory alloys (SMA) was introduced in the finite element analysis to calculate the deformation of two or three-dimensional elements. To verify the finite element model, tensile tests for SMA films were performed. The load-displacement relationship and temperature distribution during the loading and unloading were measured and compared with the numerical result. The temperature distribution visualizes the phase transformation because the martensitic transformation is exothermic whereas the reverse transformation is endothermic. The load-displacement relationship was non-linear and had a hysteresis loop. The numerical result could capture such a deformation behavior. Several diagonal higher temperature bands appeared in an SMA film during the loading. The numerical result could not capture them well. Further modification is needed in the finite element model.
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Hisaaki TOBUSHI, Toshimi SAKURAGI, Yoshiki SUGIMOTO
Article type: Article
Session ID: 1002
Published: August 02, 2008
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The torsional deformation properties of a TiNi shape-memory alloy thin strip were investigated. The results obtained are summarized as follows. (1) The martensitic transformation starts at the edge of the thin strip. (2) The torsional deformation properties change slightly under thermomechanical cycling. (3) The fatigue life in pulsating torsion is longer than that in alternating torsion. (4) A simple rotary driving element can be developed by using the SMA thin strip.
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Pio John BUENCONSEJO, Hee Young KIM, Shuichi MIYAZAKI
Article type: Article
Session ID: 1003
Published: August 02, 2008
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A novel method of fabricating superelastic Ti-Ni microtubes was developed. Ti-Ni was sputter-deposited on a Cu-wire with a 54μm diameter. After deposition the Cu-wire was removed by etching to produce a tube hole. The microtubes exhibited shape memory behavior after heat-treatment at 873K for 3.6ks. A high-strength Ti-Ni microtube that exhibits superelasticity at room temperature was obtained. The fabricated superelastic Ti-Ni microtube is attractive for biomedical applications, such as micro-stents, micro-needles and micro-catheters.
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Hiroki CHO, Takaei YAMAMOTO, Toshio SAKUMA, Yutaka SAKURAI
Article type: Article
Session ID: 1004
Published: August 02, 2008
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The method by controlling a magnetic field as one of the methods of making composition control of Ti-Ni sputtering thin film was invented. This method is controlled the sputtering area of Ti and Ni by controlling a magnetic field using Ti-Ni/Ni compounding target. The control of a magnetic field was carried out with solenoid coil and the target has been arranged to the center of a coil. The variation of magnetic field is controlled by the input current. In this study, the composition of Ni decrease with increasing of input current, and composition control is possible in the range Ni concentration is 49-55at%. So that it turns out that control of composition is possible at controlling of the magnetic field. However, the thin film became brittle by the increase of input current. It is thought that this is for decreasing the kinetic energy of the sputtering atoms (Ti and Ni-atoms) by magnetic field.
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Hidehiko Kimura, Yoshiaki Akiniwa, Ju Yang, Keiichi Fukuoka
Article type: Article
Session ID: 1005
Published: August 02, 2008
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Fatigue property of shape memory alloy TiNi in the form of thin film was investigated. The specimens with the thickness of 6 mm, 2 mm and 0.5 mm were fatigued in order to clarify the effect of the constraint of martensitic phase, which possesses higher fatigue crack propagation resistance than that of austenite. The results show that crack propagation rate was lower in the thin specimen. This is attributed the existence of higher hydrostatic pressure in the thick specimens. The hydrostatic pressure is considered to lower martensitic transformation. As a result, TiNi thin film actuator is expected to have superior fatigue property than the bulk samples. In order to evaluate the properties of the TiNi thin film actuator, the diaphragm was produced on Si/SiO_2 substrate. The heating and cooling process shows that the TiNi diaphragm moves in the substrate direction when constrained in the right way.
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Katsutoshi MAEDA, Kenji KANEKO, Kazuki ENOMOTO
Article type: Article
Session ID: 1006
Published: August 02, 2008
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A shape memory alloy (SMA) is generally used under cyclic phase transformation condition. In this paper, phase transformation fatigue strength of SMA tape is investigated experimentally. It is found that cyclic number at fracture due to cyclic M-phase - P-phase transformation is very small even for rather small load. This is because internal stress is generated by uneven phase transformation due to uneven temperature distribution R-phase transformation does not require wide range of Temperature. The transformation between R-phase and P-phase is superior to M-P phase transformation for prolonging SMA's life and having a larger SMA's total work up to fracture.
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R. Matsui, T. Osumi, K. Shintani, H. Kyogoku, F. Yoshida
Article type: Article
Session ID: 1007
Published: August 02, 2008
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Functionally graded TiNi shape memory alloy wires were fabricated using powder metallurgy and plastic working processes. In the sintering process, mixed TiNi powders of several compositions were prepared using ball milling process. The prepared powders were filled layer by layer into the graphite die. The sintered TiNi SMA billets were extruded to wires at 1073 K. Transformation temperatures and texture morphologies in the several parts of the extruded wires were investigated.
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Akihiko SUZUKI, Hideo SHIBUTANI, Takaei YAMAMOTO, Hiroki CHO, Toshio S ...
Article type: Article
Session ID: 1008
Published: August 02, 2008
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This paper describes experimental results for stress - strain behavior of Ti-Ni shape memory alloys in the super elastic regime. Cylindrical hollow test pieces were loaded and unloaded by the strain control in the multi-axial (axial-shear) strain space under the proportional loading condition. Test results showed the complicated stress-strain behavior of the material under multi-axial stress-strain states.
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Akira TERAYAMA, Hideki KYOGOKU
Article type: Article
Session ID: 1009
Published: August 02, 2008
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Ti-Ni-Cu shape memory alloys were fabricated by powder metallurgy (P/M) process. The blended powders of three compositions of Ti-50.2at%Ni, Ti-40.2at%Ni-10at%Cu and Ti-30.2at%Ni-20at%Cu were milled using planetary ball mill. These powders were sintered using pulse-current sintering equipment. The effect of Cu addition on the shape recovery strain and critical stress for slip deformation of the alloys were investigated. Increase in Cu addition increases the shape recovery strain of the alloy, but it decreases the critical stress for slip deformation because of a number of pores formed by Cu addition. In the thermal cycling test, the plastic strain of the alloy of Ti-30at%Ni-20at%Cu was lower than that of the other alloys in an applied stress more than 75 MPa. The plastic strain of the alloy was 0.06% under an applied stress of 175 MPa.
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Kazuhiro KITAMURA, Yukiharu YOSHIMI
Article type: Article
Session ID: 1010
Published: August 02, 2008
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The rolling reduction of a cast shape memory alloy (SMA) plate from self-propagating high temperature synthesis (SHS) ingot was investigated. DSC and Tensile test specimens were cast by lost-wax process from SHS ingot. The heat treatment conditions were 400℃-600℃ for DSC and tensile test. Transformation temperatures were measured by differential scanning calorimetry (DSC). Mechanical properties were measured by a tensile test at several temperatures. The effect of rolling reduction was investigating this study.
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Yuji KIMURA, Hajime Uchiyama
Article type: Article
Session ID: 1011
Published: August 02, 2008
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Ni-Ti alloy have been investigated for applying in various surgical procedures in these days. However, little is known about the toxicity of Ni-elements and the actual conditions of surface modification of Ni-Ti alloy. In this study, the corrosion resistance of Ni-Ti alloy was improved through making TiO_2 thin film by in air oxidation and reactive sputtering. These thin films were characterized using FE-SEM, XRD, XPS and Electrolysis Reduction. And judging from the polarization curves obtained by electro-chemical measurement in quasi-living body environment, corrosion resistance of Ni-Ti super elastic alloy was evaluated. From these considerations, some trials were conducted for establishing a method for TiO_2 thin film formation method on the surface of Ni-Ti alloy.
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Iyoko KUBOTA, Tomonari INAMURA, Kenji WAKASHIMA, Hideki HOSODA, Shuich ...
Article type: Article
Session ID: 1012
Published: August 02, 2008
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Texture of wire of Ti-24mok%Nb-3mol%Al biomedical shape memory alloy was investigated by electron backscatter diffraction pattern (EBSP) and X-ray diffraction (XRD) analysis. The alloy is parent β(bcc) phase at room temperature and exhibits superelasticity. An ingot was fabricated by Ar arc-melting and homogenized at 1273K for 7.2ks in vacuum and then quenched into water. The ingot was cold-drawn with a reduction in cross-section about 90% and a wire with a cross-sectional diameter of 1mm was successfully obtained. The solution-treatments at 873K, 973K, 1073K, and 1173K for 3.6ks were made to evaluate the effect of annealing temperature on the recrystallization texture. The fiber texture of <102>_β was formed in the wire which was solution-treated at 873K and as-rolled one. The texture was broaden and approached to the <110>_β fiber texture with the increase in the solution-treatment temperature. The wire is used in a bending mode in the practical use and superelastic deformation in tension and compression along the wire-direction is necessary. The maximum transformation strains of the β-α"(C-orthorhombic) thermoelastic martensitic transformation are +2.6% and -2.1% along <102>_β whereas they are +2.9% and -0.8% in the <110>_β fiber texture. <102>_β texture is, therefore, favorable for the wire material in this alloy.
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Hiroyasu ISHIKAWA, Yuji SUTOU, Toshihiro OMORI, Ryosuke KAINUMA, Kiyos ...
Article type: Article
Session ID: 1013
Published: August 02, 2008
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Martensitic transformation and superelasticity in Pd-In-Fe alloys were investigated. Pd-In-Fe alloys show martensitic transformation from a Heusler-type L2_1 ordered bcc phase to a 2M-type DO_<22> structure. It was confirmed from compressive test and three-point bending test that an almost perfect superelastic effect accompanying the stress-induced martensitic transformation can be obtained. Since high corrosion resistance and specific gravity are expected in these Pd-based shape memory alloys (SMAs), the present alloys are potentially applicable for medical devices.
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Hiroyuki SAITO, Tomonari INAMURA, Kenji WAKASHIMA, Hideki HOSODA, Shui ...
Article type: Article
Session ID: 1014
Published: August 02, 2008
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Although NiTi shape memory alloys are used extensively as biomedical applications such as stents and orthodontic wires, Ni is known as a toxic metal element. Thus, development of Ni-free shape memory alloys is required for biomedical applications. A candidate is Ti-base shape memory alloys. Although shape memory effect of Ti-Nb alloys has been widely investigated, comparably limited data has been obtained for Ti-Mo base alloys. It is known that the martensitic transformation temperature (M_S) from β parent phase to α" martensite phase is much lowered by Mo addition than by Nb addition, whereas few studies exist about the effect of ternary additions on M_S of Ti-Mo alloy. In order to clarify the effect of ternary additions on shape memory effect and mechanical properties comprehensively, Ti-Mo base alloys containing 3d transition metal elements were systematically investigated in terms of phase constitution and mechanical properties. It was found that the addition of 3d transition metal elements reduces M_S of the α"-martensitic transformation, and that all the ternary additions suppress the formation of the ω-phase which causes embrittlement. No alloy exhibited clear superelasticity. 1mol% addition of these 3d transition elements improves both the strength and ductility. Further additions of Co and Ni degrade the ductility due to large hardening. However, only Fe addition clearly improves strength without lowering ductility. Thus, Fe addition is effective to improve mechanical properties of Ti-Mo alloys.
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Akihito GOTO, Tomonari INAMURA, Hideki HOSODA, Kenji WAKASHIMA
Article type: Article
Session ID: 1015
Published: August 02, 2008
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Ferromagnetic shape memory alloys (FSMAs) can have larger strain and more quick response than presently-used actuator materials. In FSMAs, the magnetic field-induced strains (MFISs) result from rearrangement of martensitic variants by magnetic field. Several research groups have reported large MFISs〜10% in some nonstoichiometric NiMnGa "single crystals". However, they are essentially irrecoverable upon removal of the field. In our laboratory, NiMnGa/polymer composites are proposed for recoverable MFISs. Polycrystalline NiMnGa was crushed into particles and they were embedded in a polymer matrix. The particles are essentially single crystals. In the present study, rearrangement of twin variants under externally applied fields were observed in embedded particles.
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Toshihiro OMORI, Yuji SUTOU, Naoki KOEDA, Ryosuke KAINUMA, Kiyohito IS ...
Article type: Article
Session ID: 1016
Published: August 02, 2008
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The microstructure and superplastic behavior at 450℃ and 500℃ were investigated using optical microscopy and a tensile test in Cu-Al-Mn-Ni shape memory alloy. It was found that a fine α(fcc) + β(bcc) two-phase structure with grain size of 3μm in diameter can be obtained by annealing at 600℃. The flow stress of the Cu-Al-Mn-Ni alloy is dependent on both the strain rate and the test temperature where the strain rate sensitivity is over 0.3 which exhibits superplasticity with the elongation of over several hundred percents. For the test temperature at 500℃ and the strain rate of 5×10^<-4> sec^<-1>, the maximal elongation of 1150% was obtained.
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Shinichi SUZUKI, Toru YAMAGUCHI, Haruki Yoshitake, Hiroyuki NARITA
Article type: Article
Session ID: 1017
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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Photoelasticity is applied to measure the strain of the lenses of glasses. The lenses are fixed to two kinds of glasses frame, the old frames and the new ones whose rim lock mechanism is improved to reduce the strain of the lenses. The measurement results show that the strain of the lenses fixed with the new rim lock mechanism decreases by about 33% on the average of whole area of the lenses, compared with the old mechanism. At the center of the lenses, however, the strain of the lens fixed with new rim lock mechanism is roughly the same as that of the lenses fixed with the old rim lock mechanism.
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Nobuhiro AOYAGI, Tsutomu EZUMI
Article type: Article
Session ID: 1018
Published: August 02, 2008
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The major part of stress analysis for a manhole cover is the numerical analysis. The experimental analysis was rarely done recently. In this research, the experimental analysis was done for the manhole cover using the stress frozen method. The stress concentration was confirmed at the edge of the load and the edge of the cover. The transmission of the load was confirmed on the cover including the rib under the partial load. It has been understood that careful corresponding is necessary in the shape and size of the volume fillet surface in the safety design.
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Yudai NOMURA, Eisaku UMEZAKI
Article type: Article
Session ID: 1019
Published: August 02, 2008
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A new phase assigning algorithm for an automatic determination of the isochromatic parameter (relative fringe order) from a single color isochromatic image using fringe gradient and RGB wavelengths techniques is presented. This method uses the following three data: (1) the fractional phase retardation whose profile are of a saw-tooth type; (2) the points of reversal of increase or decrease in the fringe orders; and (3) the first unwrapped phase regions, which are used as seed points. The fractional phase retardation are obtained from a single color isochromatic image using fringe gradient technique. The points of reversal of increase or decrease in the fringe orders; and the first unwrapping phase regions are extracted from the isochromatic image using RGB wavelengths technique. To evaluate the effectiveness of the proposed method, a single color isochromatic image for a circular ring subjected to a concentrated load was used. Results showed that the proposed method yields the accurate relative fringe orders of isochromatics.
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Katsumi INOUE, Takuya IKEDA, Yukihito NARITA, Tomoya MASUYAMA
Article type: Article
Session ID: 1020
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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Several methods of fatigue life assessment have been proposed on the basis of damage mechanics. In this research, as-received and carburized test specimens are loaded by a pulsating test rig, and variation of elastic strain in fatigue process is measured by image processing. From the test result, damage accumulation in the test specimens is evaluated based on damage mechanics. This method is then applied to the evaluation of fatigue damage of carburized gears under cyclic loading and the prediction of residual life is discussed.
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Akira KATO, Tin Aung MOE, Satoshi KOMURA
Article type: Article
Session ID: 1022
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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We investigated a method to evaluate fatigue damage of steels without contact using laser. The technique is based on observation of reflected light pattern by a laser light illuminated on the specimen surface. The reflected light pattern changes by diffusion on specimen surface due to slipbands by fatigue and we can evaluate fatigue damage observing diffusion pattern change. We previously used a spot beam and made an observation at a point. In this study, we tried to develop a method to evaluate fatigue damage in the whole view field with a CCD camera. We used an optical setup using a slit beam and whole field observation was made by scanning the slit beam. The results showed that there is a possibility of visualizing fatigue damage and detecting fatigue area in the whole field and also evaluating fatigue damage by the optical setup using slit beam.
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Islam Md. Nurul, Yoshio ARAI
Article type: Article
Session ID: 1023
Published: August 02, 2008
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The objective of present study is to develop a method of evaluating the low cycle fatigue crack initiation of stainless steels SUS304 using ultrasonic back scattered wave. A change in back reflection intensity from the surface of the material under cyclic loading was measured. Back reflection intensity decreased before the fatigue crack initiation as the number of cycle increased. Attenuation is caused by the movement of dislocation and this mechanism was considered.
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Senji IMAMURA, Jun HIROSE
Article type: Article
Session ID: 1024
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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The mechanical properties of a material change with the cross-sectional form, size and test atmosphere of the material. For this reason, the intelligent universal tester equipped with an intelligent control program was used as a testing machine. In order to measure the mechanical properties of the material, the test conditions must be chosen appropriately according to the various states of the material. In deciding the test conditions, elastic or plastic behaviors must be distinguished clearly. The elevated tensile speed V_1 and the step stress σ_<st> reduced. In this study, the optimum test conditions were elucidated using SUS303 stainless steel specimens of two different chemical compositions and outer diameters.
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Yuichi ONO, Seiichiro KITAOKA
Article type: Article
Session ID: 1025
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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Nickel-phosphorous alloy foil with conical projections is used for high contact pressure measurement. The foil arranged projections high density and heated at 400℃ is possible to measure pressure about 1.5GPa. It is clarified that the real contact pressure occurred at real contact area of projections is responsible to the plastic deformation of projections. The relationship among contact pressure, plastic deformation of projections, and projection density is formulated experimentally. The contact pressure distribution between flat end of a circular cylinder and an elastic plane is measured by this method. The pressure gradually increases with approaching cylinder edge. Moreover, the pressure of center portion becomes small and the edge pressure becomes large as the modulus of rigidity of cylinder becomes high. This tendency is analogous to the numerical calculation result.
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Satoru ODAHARA, Masahiro INOUE, Takayuki FUKUDA
Article type: Article
Session ID: 1026
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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Recently, drains of fossil fuel and the increase of the amount of CO_2 discharge are fatal issues for earth environment. Wind turbine with brimmed diffuser has the power generation efficiency of 4 times as high as the conventional wind turbine. The accidents of wind turbine with brimmed diffuser were caused for several times. However, there are no researchers on the fatigue strength and the fatigue life of the new wind turbine. Then, the purpose of the study is to estimate the fatigue strength and the fatigue life of the wind turbine with brimmed diffuser. The service strain of blades with the variation of wind velocity and wind direction was measured by wireless strain measurement system. The results show that the higher the variation ratio of the wind velocity and the wind direction are, the larger strain variation of the wind turbine blades. In addition, fatigue life based on the modified Miner rule was estimated by the strain data. The fatigue life of the wind turbine blades was five years estimated on the base of the strain data at the wind tunnel equipment.
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Taiki HOSHI, Eisaku UMEZAKI, Katsunori FUTASE
Article type: Article
Session ID: 1027
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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Recently, the authors have developed a new container used for liquid food products such as soy sauce and milk, which consists of a paper case made of a sheet of recycled paper and a liquid-packing bag made of plastic film. One of the major features of the new container is that the container is capable of delaying the discoloration and decay of liquid food products. It was inferred that this function is due to the prevention of the invasion of microorganisms from a simple pouring lip into the bag; the lip is made of the same plastic film as the bag and is located in the upper part of the container. However, the reason microorganisms could not enter the bag remains to be determined. In this study, as a first step toward determining the above reason, the velocity of movement of colon bacillus in liquid in microchannels made to simulate the lip of the new container was measured using a digital image correlation technique. Results indicated that the existence of nutrition and increase in the gap size of rectangular channels increased the swimming speed of colon bacillus, and the ratio of colon bacillus adhered to the wall surface of the channels increased with decrease in the gap size. The shape of bacteria changed due to the existence of nutrition.
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Motoharu FUJIGAKI, Yosuke SUGIMOTO, Yoshiharu MORIMOTO
Article type: Article
Session ID: 1028
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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To measure an object shape in time series, a high-speed shape measurement technique is requested. The sampling moire method gives the phase information of the grating from a one-shot grating image. The captured image is analyzed by performing easy image processing, i. e., thinned-out and linear interpolation, to obtain the multiple phase-shifted moire patterns. Then, the phase distribution of the moire pattern can be calculated using phase-shifting technique. In this paper, we proposed a stereoscopic shape measurement for high-speed rotating object using one-shot phase-shifting sampling moire method. The principle and the experimental result are shown.
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Kenta WATANABE, Eisaku UMEZAKI, Katsunori FUTASE
Article type: Article
Session ID: 1029
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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Plastic and paper containers used for liquid products have some problems such as increase in amount of plastic garbage and consumption of paper resources. To solve these problems, the authors have been developed a new container for liquid of food products, which consists of a paper case made of sheet of recycled paper and a liquid packing bag made of a plastic film. In this study, the deformation of liquid packing bags, in which liquid was packaged, subjected to drop impact is investigated. Results indicated that the liquid packing bags have characteristic bulge, which vary with time, and the variation of the shape of the bags can be explained using the variation of pressure in the bags estimated from the water hammer theory.
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Toshio MADA, Kazuo ARAKAWA, Tetsuo SHIMIZU, Masanori SATOU
Article type: Article
Session ID: 1030
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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The oblique impact between a golf ball and a rigid steel target was studied using a high-speed video camera. The displacement and rotation angle of the ball were measured to determine the tangential velocity, the rotation angle and angular velocity of the ball during the impact. The ball center acceleration was also determined, and the contact force was calculated by the product of the acceleration and the mass of the ball. The impact behavior of the ball was then discussed.
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Yasuyuyki MORITA, Hisashi INOUE, Mitsugu TODO, Yasuyuki MATSUSHITA, Ka ...
Article type: Article
Session ID: 1031
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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We propose a non-contact displacement measurement method for various materials based on laser-induced ultrasound. We illuminate nanosecond pulse laser to a material surface. The various kinds of elastic waves whose maximum frequency is several hundred MHz are excited by laser-induced ultrasound. And then, only elastic waves which depends on the thickness of specimen remains selectively. The elastic waves occur displacement. We propose the collector optics type Twyman-Green interferometer as non-contact measurement method for displacement of rough surface. Using the aluminum whose thickness is 1.0 mm, we can detect the resonance signal of elastic waves and the resonance frequency that is 3.8 MHz by FFT.
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Shinichi Suzuki, Yusuke Yoshida, Mohamad Sharul Mizan Bin
Article type: Article
Session ID: 1032
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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A concave cylindrical surface of solid is irradiated by pulsed laser beams in water. The laser irradiation generates cylindrical underwater shock waves that propagate and converge at the axis of the cylinder. The pressure waveforms of the shock waves are measured at the focal point, where the shock wave consists of a positive pressure pulse and a negative one that follows the positive pressure pulse. The pressure waveforms are measured with varying the intensity distribution of the laser beam on the cylindrical surface. Three kinds of intensity distribution are used, that are uniform, Gaussian and two tops distribution. The measurement results show that the ratio of the negative peak pressure to the positive one is about 0.55, and does not change much even though the intensity distribution of laser beam varies.
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Nobuo NAGASHIMA, Masao HAYAKAWA, Etsuo TAKEUCHI
Article type: Article
Session ID: 1129
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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The influences of hydrogen on nano-indentation of IF-steel were investigated. The results obtained are as follows. (1) The "pop-in" was observed in the hydrogen uncharged specimen. (2) The "pop-in" was not observed in the hydrogen charged specimen. (3) The "pop-in" was observed in the specimen which heat treated at 200℃/1h. (4) The "pop-in" was observed in the specimen which charged with hydrogen after the heat treatment at 200℃/1h.
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Tatsuo SAKAI, Kosuke NISHIOKA, Akira UENO
Article type: Article
Session ID: 1131
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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In evaluation of fine ceramic components reliability, it is very important to know residual stress introduced to the material surface in the fabrication process. X-ray diffraction method has been sometimes used to measure the residual stress for ceramics, but there are some difficulties in both high cost and harmful radiation. To overcome such difficulties, a simple method to measure the residual stress based on the indentation fracture (IF technique) was standardized by the Society of Materials Science, Japan, in 2001. In order to verify this method, the residual stress induced by bending load was actually measured. Thus the residual stress obtained was in good agreement with the stress artificiality given by bending loading machine.
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Kohii MINOSHIMA, Akio YONEZU, Yoshiki KUWAHARA, Masayuki SAKIHARA, Yoh ...
Article type: Article
Session ID: 1132
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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Indentation method was developed to evaluate mechanical properties of cold-worked material. This method uses dimensional analysis to identify the material constants of plastic constitutive equation. We applied the developed method to cold drawn austenitic stainless steel (SUS316L) rod. The estimated proof stress and pre-strain as well as stress-strain curve agreed with those obtained by micro tensile tests. It is also found that near the surface of worked rod, both proof stress and pre-strain were higher. The developed technique can quantitatively evaluate the local mechanical properties.
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Masashi YOSHIDA, Yuitiro OKAMURA
Article type: Article
Session ID: 1133
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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A tensile test up to 10% have been performed of an iron polycrystalline plates and strain distribution has been investigated using the digital image correlation analysis methods. Lattice rotation after the tensile test has been investigated by electron beam back-scattering pattern (EBSP) method. Strain distribution can be obtained with spatial resolution of as high as 10 μm and strain resolution of 1%. It has been found that one grain separates into several regions where different slip systems are activated. The subdivision of grains is found to occur by the lattice rotation around the <1,1,0>axis, which is brought about by the activation of different slip systems in adjacent regions separated by a (0,0,1) plane.
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Masahiro TAKAKI, Satoshi KAKUNAI, Naoki FUKUMURO, Shinji YAE, Hitoshi ...
Article type: Article
Session ID: 1134
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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The electro deposits of Zn, Cu, and Ni were generated on the copper substrate of the cantilever beam, and the internal stress was measured in-situ by using the TV holographic interferometry which can capture holographic images at TV frame rates. Moreover, the surface and cross section of the deposition were observed by using SEM and TEM. As a result, the large variation of internal stress was caused in the initial stage in which the plating grains with a thin film deposit.
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DAIJIROH Shiraisi, TOMOAKI Takatsu, KIYOAKI Tanifuji, Haruo ENDOH, Tsu ...
Article type: Article
Session ID: 1135
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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In this study, the nondestructive detection of an internal defect in the weld metal of an aluminum plate has been demonstrated using a photoacoustic microscope (PAM). The internal defects with actual defect in a specimen were fabricated in the inside of weld metal by the welding. The nondestructive detection of the position and size of the internal defect was carried out using the PAM. In addition, X-ray tomographic imaging was also carried out for comparison with the obtained PAM images. The information on depth direction and size of the internal defects was obtained from photoacoustic (PA) amplitude images and the signal intensity distribution.
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Kunihisa FUKUDA, Shijie ZHU
Article type: Article
Session ID: 1136
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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Thermal barrier coatings consisting of ZrO_2-8wt%Y_2O_3 and NiCoCrAlY bond coat on a Ni base superalloy were used as test specimens. The indentation fatigue tests were conducted before and after thermal exposure test. The thermally grown oxide (TGO) layer increases with increase of thermal exposure time up to 200h. The interfacial damage was observed using scanning electronic microscope and digital microscope. The debonding and spalling of ceramic top coat occurred in the specimens thermally-exposed for 200h.
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Tatsunori HAYASHI, Takao MORI
Article type: Article
Session ID: 1137
Published: August 02, 2008
Released on J-STAGE: August 01, 2017
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The role of a pressure sensor is to display pressure definitely for at least 2000 hours. However, a residual strain after reloading occurs in the diaphragm using in the high-pressure. This study involved a finite element analysis of the sensor. As the result of the analysis, the residual strain was improved by making the thickness of diaphragm thicker. However, it is thought that the sensitivity of a sensor may become poor. Therefore, it is important to reduce the force by optimizing the structure. Measurement accuracy and durability is required of high-pressure equipment. Therefore, it is important with the diaphragm type pressure sensor to examine the influence that shape and the size of diaphragm exert on the measurement accuracy and durability. As a first step, the diaphragm size was clarified. A finite element method (FEM) based on the experimental design was used. And, to optimize the size of the diaphragm, each part was examined by clarifying the stress and warp distributions.
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