著者

寺沢 憲 久納 孝彦 水野 正夫

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.47, no.414, pp.113-122, 1981-02-25

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著者が提唱した超音波加熱による熱処理の原理は, 材料を超音波振動させた際に, 材料自身の内部摩擦により生じた熱を利用することにある. 本研究の目的は超音波加熱の実用性, はん用性を広げることにある. 材料に種々のおもりをふかし, 加熱の位置, 共振周波数などの変化を調べた結果, 材料の長さおよび加熱部の位置を任意に選ぶことが可能になった. 又, 超音波熱処理の一環として, 超音波加熱による焼きもどしを試みた.

著者

山崎 光悦 韓 晶 石川 秀樹

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.64, no.620, pp.1077-1083, 1998-04-26

参考文献数

11

被引用文献数

9 6

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The crushing behavior of cylindrical shells subjected to an axial impact force is studied by FEM, and a comparison between numerical results and theoretical predictions as well as a qualitative comparison between numerical estimates and experimental results are made and discussed. Moreover, a crashworthiness maximization technique for shell structures is developed and applied to the axial crushing problem of cylindrical shell. In the program system presented in this study, an explicit finite element code, DYNA3D is adopted for simulating complicate crushing behavior of shell structures. The response surface approximation technique is applied to construct an approximated design sub-problem in the preassigned design space by using the technique of design-of-experiment. The approximated sub-problem is solved by the usual mathematical programming technique. These optimization processes is repeated until the given convergence conditions will be satisfied.

著者

東藤 貢 高橋 清 JAR BenP.Y. BEGUELIN Philippe

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.65, no.631, pp.432-438, 1999-03-25

参考文献数

21

被引用文献数

1 1

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Toughening mechanisms of three types of rubber toughened poly (methyl methacrylate) (RT-PMMA) were investigated under mode I loading condition by optical and electron microscopies in conjunction with the quantitative evaluation of mode I fracture toughness. Polarized optical microscopy clearly exhibited damage zone development ahead of a crack-tip of the RT-PMMAs. The three RT-PMMAs revealed different shapes of the damage zone. Transmission electron microscopy exhibited microcrazes nucleated in the equator of rubber particles within the damage zones. Extensive deformation of rubber particles corresponding to localized shear yielding of the PMMA matrix was also found in a region close to a propagating crack-tip. In addition, cavitation of rubber particles was observed in the vicinity of the crack. It is therefore understood that the toughening of the RT-PMMAs is due to energy dissipation caused by the microdamage formations such as microcrazing, matrix shear deformation and rubber particle cavitation ahead of the crack-tip.

著者

森本 吉春 瀬口 靖幸 東 利彦

出版者

一般社団法人日本機械学会

雑誌

日本機械学会論文集 A編 (ISSN:03875008)

巻号頁・発行日

vol.54, no.504, pp.1546-1552, 1988

被引用文献数

5 10

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By shifting the discrete Fourier spectrum of the image of a deformed grating, we can obtain "the complex moire pattern". Strain distribution is given as the derivative of the argument of the complex moire pattern. The analysis is completely automatized by introducing the digital image processing. All of the laborious and subjective procedures reguired in conventional analysis such as fringe sign determination, fringe ordering, and fringe interpolation are completely eliminated and objective, fast and accurate analysis can be made.

著者

小島 清美 寺崎 健 三浦 英生 西村 朝雄

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 = Transactions of the Japan Society of Mechanical Engineers. A (ISSN:03875008)

巻号頁・発行日

vol.69, no.686, pp.1409-1414, 2003-10-25

参考文献数

20

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A practical structural design system for LSI packages has been developed based on object oriented and graphical user interface technologies. An object-oriented technology is applied for creating product model-based analytical model (PBAM) which is independent of analytical method or tool. It is easy to create any CAE model from the PBAM. Graphical user interface is another effective technology for easy operation. Design engineers only have to select a model of interest and revise the dimensions or materials of the package, if necessary. As soon as they finish revising the input data, a CAE model such as finite element meshes are generated and the analysis starts automatically. The life of the solder joints, for example, is automatically evaluated and the results are displayed on a CRT. This system is very effective for designing new, highly reliable LSI packages in a short time.

著者

鈴木 秀人 ? 偉民 永井 邦和 松山 健也 伊藤 吉保 柴田 良一

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.61, no.585, pp.894-899, 1995-05-25

被引用文献数

20 5

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An influence of cooling rate on the fatigue reliability of aluminum alloy castings (AC4CH) was investigated. The results obtained were as follows : (1) As the cooling rate of AC4CH was increased, the porosities and the microstructure were controlled fine. (2) The fatigue strength of AC4CH produced through rapid cooling rate was superior to that produced through slow cooling rate, specially on the fatigue limit (N=10^7). (3) The effect of stress gradient on the fatigue limit is due to the probability that the maximum stress can put on the largest porosity in the specimen. (4) Micro porous defects were always observed at the origin of fatigue crack. Then, it could be interpreted that the fatigue life was related to the size of porous defect, based on fracture mechanics. (5) From the above relation and the statistical analysis on the size of porous defect, the fatigue limit of 99% remaining probability could be estimated.

著者

石田 和雄 小林 信之

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.50, no.453, pp.1042-1048, 1984-05-25

被引用文献数

2 1

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An effective method for calculating the nonlinear-rocking response of ground-supported unanchored cylindrical tanks to earthquakes was developed. In this method, tank wall and liquid content are replaced with a mass-spring system, and the nonlinearity associated with the partial uplift of bottom plates due to overturning moments is considered as the rotational spring of bi-linear type which is determined by a static uplift analysis of tank bottom. The reliability of the dynamic analysis was illustrated by computing resonance frequencies, response accelerations and rotation angles of tank models and by comparing them with the results of vibration tests. A seismic deign procedure for nonlinear rocking of tanks is proposed, in which the uplift height of bottom plates is calculated by dynamic rocking analysis and the corresponding radial stress of them is obtained by static analysis. And a rocking analysis of a full-sized tank was tried, too.

著者

小林 信之 石田 和雄

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.50, no.451, pp.514-519, 1984-03-25

被引用文献数

1

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When an earthquake hitting, the part of the bottom plate of the unanchored cylindrical tank will be lifted up from the foundation so that no resistance mechanism is existed against the uplift force caused by the overturning moment. The high stresses will be yielded in the bottom plate and the shell plate. This report concerns those problems. The calculation model was made in order to obtain the uplift resistance force, the uplift height, the reaction force from the foundation and the uplift region. In this model, the uplift region was considered as crescent shape, and the elasto-plastic, large deformation effect and the contact problem of the bottom plate was considered. From the comparison between this calculation model and the static tilt test of a thin bottom plate model tank, the calculation result was good agreement with the test.

著者

菊池 正紀 和田 義孝 高橋 真史

出版者

一般社団法人日本機械学会

雑誌

日本機械学会論文集. A編 = Transactions of the Japan Society of Mechanical Engineers. A (ISSN:03875008)

巻号頁・発行日

vol.74, no.742, pp.812-818, 2008-06-25

参考文献数

15

被引用文献数

10

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Fatigue crack growth under mixed mode loading conditions is simulated using Superimposed-FEM (S-FEM). By using S-FEM technique, only local mesh should be re-meshed and it becomes easy to simulate crack growth. By combining with re-meshing technique, local mesh is re-meshed automatically, and curved crack path is modeled easily. At first, slant crack problem is solved. It is shown that results agree with conventional solutions, and verified the availability of this technique.Then two-crack problems are solved in several cases by changing each crack location. Stress intensity factors are evaluated and interaction effect between two cracks is discussed. Results are compared with crack coalescence criteria, and it is verified that these criteria are reasonable ones.

著者

徳田 正孝 叶 萌 BUNDARA Borut SITTNER Petr

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.65, no.631, pp.491-497, 1999-03-25

参考文献数

45

被引用文献数

7 9

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Quite unique and interesting behaviors of shape memory alloy under complex loading conditions, including the complicated path dependency, have been observed in systematic experiments by applying some combiened loads of axial force and torque to the thin-walled tubular specimen of Cu-based polycrystalline shape memory alloy. A set of constitutive equations is proposed, which can describe the complicated behaviors observed in the experiments. The mesoscopic approach is employed in the formulation because the complicated behaviors are closely related with the microstructural changes of materials, and the obtained equations show a reasonable coincidence with the exprimental results. In this first paper, the process of modelling and the detail of formulated constitutive equations are described, and the comparison between experimental resutls and computed results by using the proposed constitutive equations are shown in the second report.

著者

尾田 十八 / 齊藤 誠 Makoto SAITO

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 A編 (ISSN:03875008)

巻号頁・発行日

vol.67, no.653, pp.121-126, 2001-01-25 (Released:2008-02-21)

参考文献数

8

被引用文献数

4 3

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Lsystem (LS) is a technique expressing a formation algorithm creating the various shape patterns by the simple rules. Using LS, the complex branch phenomena of plants could be described by simple rules. This paper has tried the methodology to apply LS to the structural design. This methodology grows up the structure as if plants grow up, and produces the optimum structure that is appropiate for the design purpose. It is difficult to acquire LS rules for the optimum structure because the rules have many degrees of freedom. Therefore, this paper proposes an idea that evolves LS rules using Genetic Algorithms (GA) . The methodology is called as an evolutionary LS (ELS) . Using the methodology, the design problems to decide optimum distribution of material and plate thickness are solved.

著者

熊谷 一男

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.46, no.408, pp.894-900, 1980-08-25

被引用文献数

1

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0. 02% C軟鋼線の, 降伏応力以下の応力を加えたひずみ時効において(1)応力は, 降伏応力の増加を最大10%促進する. (2)みかけの活性化エネルギは, 約1kcal/mol増加する. (3)応力による時効促進への寄与率は, ひずみ硬化が約20%, 新たに導入された転位への微細析出物の析出が約3%で, 促進の主たる要因は, 応力による侵入形固溶原子の拡散ならびに析出の促進と考えられることを示した.

著者

佐藤 千明 池上 皓三

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.58, no.554, pp.1913-1920, 1992-10-25

被引用文献数

2 2

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The strength of adhesive shaft joints between carbon-fiber-reinforced plastics (CFRP) and stainless steel bonded with epoxy resin was investigated in room temperature and low temperature (-70°C) both analytically and experimentally. The distributions of stress for tensile load and thermal stress for cooling in the joint were analyzed by applying the elastic finite-element method. The strength of the joints was predicted by applying the strength law of CFRP, stainless steel, adhesive layer and their interfaces to the calculated stress distributions. The predicted strength was compared with the experimental strength of the joints. The effects of the overlapped length and diameter ratio on the joint strength were examined at both conditions of room and low temperatures. The joint strength for the initial failure is saturated by a certain overlapped length, but the strength decreases with increasing diameter ratio. The final joint strength in low temperature is larger than that in room temperature.

著者

岡部 朋永 矢代 茂樹

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 A編 (ISSN:03875008)

巻号頁・発行日

vol.75, no.751, pp.304-309, 2009

参考文献数

9

被引用文献数

1 1

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This study proposes the cohesive zone model (CZM) for fatigue damage growth in the notched CFRP cross-ply laminates. In this model, the damage growth in the fracture process of cohesive elements due to cyclic loading is represented by the conventional damage mechanics model. We preliminary investigated how this model can appropriately express the fatigue damage growth for the circular crack embedded in the isotropic solid material. This investigation demonstrated that this model could reproduce the results with the well-established fracture mechanics model plus the Paris law by tuning adjustable parameters. We then numerically investigated the damage progress in notched CFRP cross-ply laminates under tensile cyclic loading and compared the predicted damage patterns with experiments reported by Spearing et al. (Compos. Sci. Technol. 1992). The predicted damage patterns agreed with the experiment results that exhibited the extension of the multiple types of damage (i.e., splits, transverse cracks and delaminations) near the notches.

著者

西川 雅章 岡部 朋永 武田 展雄

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.75, no.751, pp.287-295, 2009-03-25

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A numerical simulation was presented to discuss the microscopic damage and its influence on the strength and energy-absorbing capability of short-fiber reinforced plastic composites. The dominant damage includes matrix cracking and/or interfacial debonding, when the fibers are shorter than the critical length for fiber breakage. The simulation addressed the matrix cracking with a continuum damage mechanics model and the interfacial debonding with an embedded process zone (EPZ) model. The fictitious free-edge effects on the fracture modes were successfully eliminated with the periodiccell simulation. The advantage of our simulation was pointed out by demonstrating that the simulation with edge effects significantly overestimates the dissipative energy of the composites. We then investigated the effect of the material microstructure on the fracture modes in the composites. The simulated results clarified that the inter-fiber distance affects the breaking strain of the composites and the fiber orientation angle affects the positions of the damage initiation. These factors influence the strength and energy-absorbing capability of short fiber-reinforced composites.

著者

泉 聡志 横山 喬 寺岡 卓也 岩崎 篤 酒井 信介 斎藤 金次郎 名川 政人 野田 秀樹

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.71, no.703, pp.380-386, 2005-03-25

被引用文献数

8 16

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We have developed a new nut named 'super slit nut (SSN)', which realizes anti-loosening performance without complicated tightening procedures. In this study, tightening behavior and loosening behavior caused by shear load are analyzed by mean of three-dimensional finite element method. It is found that SSN has a prevailing torque of 15 to 19Nm, which closely agrees with experimental data. The load distribution of thread depends on the rotation angle of nut. At the angle of 24.6 degree, the distribution of 1st pitch turns to be 10% larger than that of conventional nut, reflecting the decrease in the thread at slit region. It is also found that the anti-loosening performance cas be realized by the thread contact force at the slit region. Since its contact force does not depend on the tightening force, the effect of anti-loosening performance drastically increases as the tightening force is decreased. Shear fracture would initiate not at slit region but at the bottom of 1st thread, whose stress is about 10% larger, as compared with conventional nut. Moreover, by mean of tensile and fatigue experiments, it is concluded that SSN involves sufficient strength in practical use.

著者

中西 康彦 中桐 滋

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.60, no.577, pp.2157-2162, 1994-09-25

被引用文献数

3

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This paper deals with topological optimization of elastic frames by means of the boundary cycle used in the algebraic topology and genetic algorithm. The optimum frame is so defined in this study that the deformation of an interesting point of the frame is minimal for a given limit of weight, and that any members with a tip not connected to other members, except loading points, are eliminated. The optimum topology is searched efficiently through the boundary cycle which yields the one-dimensional simplicial complex without any tip, satisfying the topological condition of no idle tip present. The boundary cycle is derived from the chain and boundary homomorphism which plays an important role of decoding of the genotype into the phenotype in the genetic algorithm, and is included in the string used in the genetic algorithm for the representation of frame topology. The numerical examples are concerned with minimization of the deformation of two-dimensional frames subject to bending, and three-dimensional frames subject to torsion or expansion.

著者

竹内 洋一郎 石田 良平 辻 正利

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.48, no.430, pp.747-757, 1982-06-28

被引用文献数

2

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有限円柱の一つの端面に偏心円形熱源のある問題は,平面熱応力問題として解決できない厚肉円板の,一方の平たん部の境界面に偏心円形熱源の問題ともなり,工業上有用性が多い.この問題は完全ないわゆる三次元熱応力問題による解析によらねばならない.本研究は熱弾性変位ポテンシャル,ミッチェルおよびブシネの関数の三者に関する熱弾性基礎方程式を解いて,非定常熱応力分布を求めた.

著者

櫻井 俊彰 多田 雅彦 石井 英章 野原 哲男 星野 裕昭 高橋 邦弘

出版者

一般社団法人日本機械学会

雑誌

日本機械学会論文集. A編 = Transactions of the Japan Society of Mechanical Engineers. A (ISSN:03875008)

巻号頁・発行日

vol.73, no.726, pp.195-200, 2007-02-25

参考文献数

4

被引用文献数

2 3

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The concept of the parameter U* has been introduced by the authors to express load transfer in structures. In this paper, an extended definition of U* is introduced for structures under multiple loadings. The new expression of U* with the matrix formulation of internal stiffness can effectively be applied to an efficient calculation of U* distribution. Examples of U* calculation for an actual truck cab structure under multiple loading are demonstrated. Calculation results of U* for cases under multiple loading condition and single loading condition are compared, and the applicability of St. Venant's principle concerning U* distribution is discussed.

著者

神宮 利夫 永倉 和郎

出版者

一般社団法人日本機械学会

雑誌

日本機械学會論文集. A編 (ISSN:03875008)

巻号頁・発行日

vol.57, no.544, pp.3069-3076, 1991-12-25

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A robotic manipulator is simplified by numerous beams with pinjoints between them and an anchor pinjoint at the base. The beams under impact loading are allowed to rotate about the axis of the pinjoint. The dynamic response of a vertical chain for a transverse load suddenly applied along every beam is theoretically analysed. The angular and linear acceleration of the mass center of beams, reaction force at the pinjoints, shearing force and bending moment along the beams is presented as a function of impact load. As the vertical chain consisting of one plaster beam and one steel beam, or two with a pinjoint between them, is subjected to the collision of the flier steel rod accelerated by the air gun, the location of the fracture of the plaster beam is measured experimentally. The validation of the theory is confirmed by comparison of the location of the critical bending moment with the position of the fracture of the beam.