著者

松田 翔太 政田 尚也 塩澤 大輝 中井 善一 三浦 亮太郎

出版者

一般社団法人日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2013, pp."OS1503-1"-"OS1503-3", 2013-10-12

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X-ray diffraction contrast tomography (DCT) is a technique for three-dimensional grain mapping of polycrystalline material. Measurement of DCT has been conducted m SPring-8 and shape and location of grain can be determined by DCT technique using the apparatus in BL19B2. For evaluation of plastic deformation by DCT, tensile and cyclic loading was applied to the sample during the measurement of DCT. The diffraction spots belonging to certain grain appear over some continuous projection images. The rotation angle range where diffraction spot appear is defined as grain orientation spread, and the grain orientation spread was counted in tensile tests and fatigue test. In the tensile test, the grain orientation spread increases in the plastic deformation. In the fatigue test, grain orientation spread increases with increasing m the number of cycles. It is possible to evaluate fatigue damage by DCT technique and using the grain orientation spread.

著者

羅 軼凡 坂本 勇人 鈴木 研 三浦 英生

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2018, 2018

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<p>Copper has been applied to the TSV interconnection structure used in microelectronic devices because of its excellent electrical and mechanical properties. However, the physical properties of copper thin film interconnections were found to vary drastically depending on their micro texture and this serious degradation of physical properties was caused by its high-volume ratio of porous grain boundaries and fine columnar grains. Thus, the long-term reliability of products cannot be guaranteed and it is largely dominated by the strength of grain boundaries. In this study, a highly-reliable evaluation method of the strength of a grain and a grain boundary in polycrystalline copper thin films was used to determine a relationship between the crystallinity and their effective strength by using EBSD (Electron Back-scattered Diffraction) analysis and micro tensile test system. The crystallinity of a grain and a grain boundary was quantitatively evaluated by using IQ (Image Quality) value calculated from the Kikuchi pattern obtained from the EBSD analysis. And the strength of a grain and a grain boundary in polycrystalline copper thin films was evaluated by using the developed micro tensile test. Finally, it was found that there was a strong crystallinity dependence of the strength of a copper grain in electroplated copper thin films. In particular, the critical resolved shear stress (CRSS) of a grain significantly decreased with the increase of the IQ value at the grain boundary.</p>

著者

アギアル デ ソウザ ヴィニシウス 渡邊 育夢 柳田 明

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2013, pp._OS0805-1_-_OS0805-3_, 2013

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The purpose of this study is to improve and extend a method to estimate the friction coefficient in equal channel angular extrusion (ECAE) including cases with back pressure. Employing three dimensional finite element analysis (FEA) and Coulomb friction model with truncated shear stress, the relationship between the friction coefficient and the reaction force is investigated in ECAE with back pressure. Additionally, the deformation state of the billet after ECAE and the pressing load are compared between the experiment and the simulation results with the same friction coefficient for validation of the numerical model.

著者

北村 一浩

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2012, pp._OS0905-1_-_OS0905-2_, 2012

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This paper reports the toy for educational tool about smart material applying Ti-Ni shape memory spring. The toy was made by shape memory spring, plastic bottle, weight, electrode, and battery. The shape memory spring was heated by current and the shape was recovered the original spring shape. The spring was flip up and disconnected the electrode. The weight was goes up and down continuously.

著者

アギアル デ ソウザ ヴィニシウス 桑水流 理 何 惠安 戸田 裕之 小林 正和

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2013, pp._OS0311-1_-_OS0311-3_, 2013

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The objective of this study is to evaluate the stress/strain distribution on a cast aluminum alloy (AC4CH-T6) employing image based nonlinear elasto-plastic finite element analysis. The numerical analysis was performed to simulate a uni-axial tension test. The geometry of the finite element model includes an aluminum matrix, silicon and inter-metallic particles which were obtained by the synchrotron X-ray micro-computed tomography (XMCT) technique. In order to create a proper finite element mesh, the Standard Triangle Language (STL) generated from the XMCT segmented volume was treated to remove geometric and structural irregularities. Results are discussed in terms of the number of elements necessary to accurately represent the stress/strain fields and the necessary computational time to simulate the problem. Additionally, results enabled visualizing the stress/strain distributions, stress concentration, and the stress/strain evolution on the three solids of interest.

著者

松村 圭悟 アギアルデソウザ ヴィニシウス 桑水流 理 小林 正和 戸田 裕之

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2014, pp._OS1204-1_-_OS1204-3_, 2014

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The crack initiation mechanism of cast aluminum alloy was addressed to quantitatively evaluate the fatigue strength. The synchrotron radiation microtomography was employed to visualize the three-dimensional damage around pores and Si particles. Two types of specimens were prepared for the low cycle fatigue test. The temperature of solution treatment was different, and it yields a difference in the shape of Si particles. After a certain cycles of fatigue, a catastrophic damage around many Si particles happened and they connected to each other so as to form a crack. The scanning electron microscopy after the test showed that the type of damage was the break of long Si particles or the interface debonding around round Si particles.

著者

本村 文孝 今井 康文 才本 明秀

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2008, pp._GS0605-1_-_GS0605-2_, 2008

被引用文献数

2

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炭酸ガスレーザを加熱源とするガラス板厚50μmの熱応力割断において,板厚をパラメータに含む板表面からの熱伝達による放熱を考慮した有限要素法を用いた3次元および2次元熱応力解析をおこなった.3次元解析では,表面発熱に起因する面外変形の拘束は応力拡大係数に影響しないことがわかった.また2次元解析にて,任意の熱源中心位置に対して熱源後方にあるき裂先端位置の応力拡大係数を評価することで,熱伝達による放熱が大きくなると,熱応力割断中のき裂進展挙動の安定性が増すことが示唆された.

著者

福田 悠一 金崎 宏 朝田 誠治 猿渡 俊也

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2012, pp._OS0803-1_-_OS0803-3_, 2012

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Current fatigue evaluation in PWR environment is determined by JSME S NF1 in which some parameters (temperature, strain rate, dissolved oxygen, etc.) are evaluated as an influencing factor. However, it is assumed that JSME Code would be conservative in high strain rate region because environmental factor (F_<en>) is evaluated by extrapolating experimental test results in low strain (up to 0.4%/sec). In this study, we obtained the experimental data and reevaluated F_<en> for high strain rate region. As a result, we confirmed that F_<en>, in 1.0%/sec strain rate was about one half of that in JSME Code. Further, marshaled experimental data got from EFT project dividing them to each stainless grade and charge, strain rate for F_<en>=1 could be lower than 3%/sec for all austenitic stainless steel and similar to current test result.

著者

鈴木 新一 ボールド エンフアムガラン バトサイハン ビルグン ジャルガルサイハン バトザヤ バヤラサイハン ヤンダグフー バドサイハン ハシエルネデ ジャワハラン ガントゥシグ アビルメデ オトゴンバヤル

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2018, 2018

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<p>Deterioration of large infrastructures that were constructed in the period of rapid economic growth is becoming a big problem in Japan these days. One method to measure the deterioration is to use optical method that can measure deformation or strain of a structure from a position far from the structure, and the other is to use a robot that moves on the surface of the structure and measures the deterioration of it. When one uses a mobile robot to inspect the deterioration, it is necessary for the robot to detect its own position. The paper describes basic experiments on the detection of position of a mobile robot. Two rotary encoders are used to measure the position of the robot as a function of time. When the robot moves by 8.7 m in <i>x</i>-direction, the error <i>Δ</i>y of the position in <i>y</i>-direction was about ±5 cm. In circular motion, the radius of real trajectory of the robot is approximately equal to the objective radius, whose error was 0.7% on the average.</p>

著者

齊藤 飛翔 笹川 和彦 森脇 健司 藤崎 和弘

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2018, 2018

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<p>Catheter insertion is a sensitive operation largely depending on tactile senses of the doctor. Although several kinds of force measurement systems attached in the catheter have been proposed, the measurement of the force during operation should be measured at the finger for evaluation of the tactile senses. In this study, we developed a film type tri-axial stress sensor that can be attached to the fingertip. An electro-conductive polymer in polythiophene series was used for the pressure sensitive layer. The conductive polymer material has a characteristic that the electric resistance in the thickness direction decreases under the compression. This type sensor is thin and flexible therefore it can be expected to directly measure the contact stress at the fingertip. In this experiment, the contact stress is measured under during catheter guide wire insertion motion. The contact stress vector including vertical and the plane directional components were detected at the gripping area of the wire. The motion trajectory of the finger in the catheter insertion was analyzed in a motion capture system. As a result, changes of the contact stress according to forward, backward, and rotation in the catheter operations were observed during insertion tests. It is possible to evaluate the catheter operation by means of the tactile sensing. Also, this measurement system can be applied not only to evaluate the skill of catheter operation but also to use for training the operation.</p>

著者

中島 晶 久保田 祥 佐々木 克彦 柳沢 祐介 岸 恭弘

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2017, 2017

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<p>The subject of this paper is to calculate the residual stress occurred during heat treatments of the large forged steel using Finite Element Method (FEM). The analysis was carried out using a cylindrical FEM model of ASTM-A-470 used in rotor shafts for power stations. First, a heat transfer analysis was performed to obtain a temperature history, which is used to calculate material properties at varied temperatures. Then, using the temperature history, structure analyses were conducted considering both the creep deformation and the transformation plasticity. The residual stresses calculated by the structure analysis were compared with the value measured by experiments. As a result, the calculated residual stresses have the same tendency as the measured residual stresses when both the creep and transformation plasticity are considered. Therefore, the importance of both the creep and transformation plasticity for the structural analysis of the heat treatment of the large forged steels was confirmed. In addition, the effect of the cooling rate to the residual stress was also discussed.</p>

著者

中尾 亮太 淺川 直也 松田 翔太 塩澤 大輝 菊池 将一 中井 善一

出版者

一般社団法人日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2015, pp._GS0205-42-_GS0205-42, 2015

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A three dimensional grain mapping technique for polycrystalline materials, called X-ray diffraction contrast tomography (DCT), was developed at SPring-8 (Super Photon ring-8 GeV), which is the brightest synchrotron radiation facility in Japan. To evaluate the fatigue damage of grains, total misorientation, β for each grain was calculated from DCT measurement. It is found that value of β increases with number of cycles, and change of β for primary slip plane is the largest in diffraction planes. In addition, the largest change of β, was observed in the diffraction plane with the largest Schmid factor, F_s in equivalent primary slip planes. From this results, it is found that change of β reflects slip behavior in a grain, because change of β correspond to Schmid factor in fcc materials which can be determined the primary slip direction.

著者

坂上 賢一 加藤 和樹 岸部 駿之介

出版者

一般社団法人 日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2017, 2017

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<p>Multicycle indentation test is applied to measure viscoelastic characteristic. In multicycle indentation test, indentation test is repeated at the same position on the specimen, and the mechanical characteristics are measured from on the impression. Therefore, the evaluation formula is introduced for the indentation measurement on the impression. An undeformed specimen and plastically deformed specimen of ABS resin are used. The result shows the measured creep compliance by multicycle indentation test is in good agreement with that by uniaxial tensile test. Thus, the proposed method can measure viscoelastic characteristics with high accuracy. Measured characteristics indicate that the undeformed specimen is isotropy but the plastically deformed specimen is anisotropy. This fact implies the development of anisotropy by reorientation and elongation of polymer chains during uniaxial plastic deformation.</p>

著者

山口 義仁 勝山 仁哉 李 銀生 西山 裕孝 鬼沢 邦雄 土居 博昭

出版者

一般社団法人日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2014, pp."OS0807-1"-"OS0807-3", 2014-07-19

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In recent years, Japanese nuclear power plants experienced multiple large earthquakes. It is very important to assess the seismic safety of piping taken the occurrence of such a large earthquake into account, when a crack exists in pipe welding joint. One of the key issues is the effect of excessive loading in the seismic response wave on the fatigue crack growth behaviour. We performed fatigue crack growth tests under constant amplitude cyclic loading with a single excessive tensile/compressive load for Ni-based alloy weld metal. Acceleration and retardation was confirmed in crack growth due to the excessive loading. The stress distribution in front of crack tip and the shape of crack tip were investigated to clarify the cause of changes of crack growth rate. A crack growth evaluation method has been proposed considering the effects of the excessive loading based on the variation of the stress distribution in front of crack tip and the crack blunting. The predicted crack growth rate by the proposed method was in good agreement with the experimental ones.

著者

渡辺 大剛 北条 公伸

出版者

一般社団法人日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2012, pp."OS0811-1"-"OS0811-3", 2012-09-22

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This paper introduces an example of structural integrity evaluation for Light Water Reactor (LWR) against excessive loads on Design Extension Condition (DEC). In order to assess the design acceptance level of DEC three acceptance criteria, stress basis of the current design code, strain basis and Load and Resistance Factor Design (LRFD) of strain basis were applied. As a result the acceptance level was increased by changing the acceptance criteria from the current stress based design code to strain based or LRFD. This means that there is possibility of practical sustainability of LWR on DEC.

著者

西嶋 修 福原 直道 平方 寛之 米津 明生 箕島 弘二

出版者

一般社団法人日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2010, pp.10-11, 2010-10-09

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This study aims to elucidate the mechanics of crack propagation in a freestanding Cu thin film deposited by electron beam evaporation We developed the method for fabricating nano or submicron meter-thick freestanding metallic films with width and length of the miffimeter order. Focused ion beam (FIB) was employed to introduce a pre-crack in an about 500 nm-thick Cu film. It is found that the crack stably propagated by uniaxial tensile loading, and then the crack propagation rate rapidly increased, resulting in unstable fracture. The fracture surface suggested that the local area near the crack tip undergoes large plastic deformation, resulting in crack propagation in ductile manner. In parallel, the elastic-plastic stress distribution around the crack tip was analyzed by finite element method (FEM). The mechanics of crack propagation and fracture toughness were investigated on the basis of the R-curve concept.

著者

大村 悦二 小川 健輔 熊谷 正芳 中野 誠 福満 憲志 森田 英毅

出版者

一般社団法人日本機械学会

雑誌

M&M材料力学カンファレンス

巻号頁・発行日

vol.2009, pp.73-74, 2009-07-24

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In stealth dicing (SD), a permeable nanosecond laser is focused inside a silicon wafer and scanned horizontally. A thermal shock wave is propagated every pulse toward the side to which the laser is irradiated, then a high dislocation density layer is formed inside a wafer after the thermal shock wave propagation. In our previous study, it was supposed that an internal crack whose initiation is a dislocation is propagated when the thermal shock wave by the next pulse overlaps with this layer partially. In this study, a two-dimensional thermal elasticity analysis based on the fracture mechanics was conducted. The internal crack propagation was analyzed by calculating the stress intensity factor at the crack tips and comparing with a threshold of that. As a result, validity of the previous hypothesis was suggested.