記述言語：日本語   出版者・発行元：公益社団法人 精密工学会  

本研究の目的は高純度単層カーボンナノチューブを高速形成することである．気相よりも分子密度の高い液相における液中熱化学気相蒸着(CVD)法での合成について調査し考察した．膜厚と合成温度の関係，触媒金属の種類によるCNT合成影響，溶液の構成元素数の違いによる影響を考察した．膜厚と温度の関係，適切な触媒金属，液中CVD法でのCNT合成手法の確立がなされた．

DOI： 10.11522/pscjspe.2017A.0_433

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

© 2017 Trans Tech Publications, Switzerland. The most progress towards a practical method of fusing municipal waste incineration ash has been in the use of a plasma jet that employs arc discharge, a form of thermal plasma. However, a remaining problem is that stable plasma generation is prevented by melting of the nozzle of the plasma-jet torch by the high-Temperature plasma flow. With the objective of developing high-speed fusion treatment for waste materials using an in-liquid plasma jet, basic research was conducted on plasma stability and the durability of plasma-jet torches, including electrodes and nozzles. Basic plasma jet characteristics such as the discharge voltage, current, and power value at the time of plasma jet generation were investigated experimentally. The relationship between the temperature distribution near the tip of a plasma jet torch and electrode damage was investigated by fluid-heat coupled analysis using the finite element method.

DOI： 10.4028/www.scientific.net/KEM.749.76

Scopus

researchmap

記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

<p>In this study, the synthesis of single-wall carbon nanotubes (SWCNT) using in-liquid CVD method is attempted. Si substrate on which Co micro particles are deposited as the catalyst is used. Electrical resistance heating method is used for glowing carbon nanotubes in pure ethanol. The synthesized materials are analyzed by scanning electron microscope, transmission electron microscope and Raman spectroscopy. As a result, the synthesis of SWCNT was successful on a wide area of the substrate surface. By investigating the synthesized carbon nanotubes changing experimental conditions such as pressure, substrate surface roughness and others, it is cleared that surface roughness of the substrate and the bubble behavior are related to the synthetic mechanism of carbon nanotubes.</p>

DOI： 10.1299/jsmeted.2016.G114

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

© (2015) Trans Tech Publications, Switzerland. Metal pipes have a long history as fluid conduits, and are commonly joined with components such as elbows to form bent transport paths. However, with the increasing demands for economy and energy saving, pipes with reduced joints and thinner walls are desired. The number of joints can be reduced by a drawing and bending process that forms a bend section at any position in the pipe. However, this approach incurs problems such as wrinkling and flattening, especially under conditions of large bending angle, decreased bending radius, and thin pipe walls. In this research, applying vibrations to the mandrel was trialed as an approach for controlling the wrinkle depth and flattening. First, processing experiments were performed on thin walled pipes (wall thickness = 0.5 mm; outer diameter = 14 mm). The change of flattening and the number and depths of wrinkles were investigated in the presence and absence of vibrations. Next, simulations were performed using the commercial nonlinear finite element software. Through these simulations, the flatness and appearance of wrinkles were analyzed by modeling the behavior and distribution of stresses and strains in the processing process. The application of vibration to the mandrel appears to be a promising approach for controlling the wrinkling and flattening problems during pipe processing.

DOI： 10.4028/www.scientific.net/KEM.656-657.600

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

This paper proposes a new near-net-shape working method to partially enlarge and control shaft's cross section through a metal mold. This study investigates the changes in the sectional area of shafts during the processing under various processing conditions, and evaluates the changes with a filling ratio. We introduce the processing method and the processing conditions, and then we report the results of processing experiments. Lastly, we clarify that processing conditions influence on the geometry of the processed part. © (2014) Trans Tech Publications, Switzerland.

DOI： 10.4028/www.scientific.net/AMM.473.35

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

We have proposed a new cold processing method to form a partial diameter-enlargement part in a hollow shaft. Using the processing method, the diameter-enlargement part with a large deformation is formed easily by applying compressive stress at yield stress level and cyclic torsional stress on two ends of specimen. In the present paper, processing experiments were conducted using the processing machine developed originally based on the processing principle, and deformation behaviors on the diameter-enlargement part were measured. In addition, the simulation analysis method in the processing was developed by the finite element method (FEM), the behaviors of stress and strain on processed part were analyzed, and deformation mechanism was investigated. It is clarified that the processing conditions affect the deformation behaviors base on the experiments and analysis. © (2014) Trans Tech Publications, Switzerland.

DOI： 10.4028/www.scientific.net/AMM.473.30

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：ELSEVIER SCIENCE BV  

We proposed a new cold processing method to partially enlarge the diameter of a shaft with a combination of a cyclic bending load and an axial compressive load that is lower than the yield stress of sample material. We call this cold processing method a diameter-enlargement working method, and call this processed part a diameter-enlargement part. Key features of the processing method are chiefly as follows: the diameter enlargement deformation progresses easily under a low axial compressive load at room temperature; the processed part has little temperature increase, although the processing causes large plastic deformation. We have tested the influence of the processing conditions and the mechanical properties of the sample materials in terms of diameter enlargement deformation behavior. However, little is known about the fatigue damage condition in a diameter enlargement part. Therefore, we carried out processing experiments to clarify crack generation conditions, and simulated working processing using finite element method in order to investigate behaviors of stress and strain during the processing. Furthermore, we evaluated low cycle fatigue damage in the processed part by using the Manson-Coffin expression. This paper clarified the mechanism of crack generation during the processing and evaluates the fatigue strength of the processed part. (C) 2014 Elsevier Ltd.

DOI： 10.1016/j.mspro.2014.06.242

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

This paper experimentally and analytically investigates the fatigue strength and of mechanical damage of the processed shafts. First, we carry out rotary bending fatigue tests and investigate the fatigue stgate strain hardening near the processed part. Finally, we simulate stress and strain distributions of the shaft during the processing using finite element method (FEM) and calculate the stress concentration rate at the notch root of the processed part. Based on the processing experiments and the finite element analyses (FEA), we clarify that the plastic work mechanically does not reduce the fatigue strength of shafts in the processing range. © (2012) Trans Tech Publications, Switzerland.

DOI： 10.4028/www.scientific.net/AMM.217-219.2346

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society for Technology of Plasticity  

A connecting work method of tightly fixing a shaft in the central hole of a circle plate was developed for application of axial-diameter-enlarging processing. This method was successfully used in tightly connecting two pieces of different material parts such as a circle plate and a shaft. Because it is performed at room temperature without either heating or cooling such as in a traditional shrinkage fitting, this work method was clarified to exhibit high performance for industrial use.

DOI： 10.9773/sosei.51.460

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society for Technology of Plasticity  

Most shafts have a hexagonal shape, gears and multi steps on their largest diameter. Here, we studied a method of deforming a partial diameter into the near-net outer shape required for practical machine parts. The method was clarified experimentally to be actualized by controlling the final outer shape of a partial enlarging diameter using a metal mold with a hole of final outer shape, which was fixed on the rotating-side holder and rotated together with a shaft of work. The diameter enlarging behavior was investigated experimentally by measuring the changes in the distance between holders. On the basis of the mathematical modeling of their deformation behavior, the effects of processing conditions on the enlarging shape were researched and an estimating equation for clarifying the engineering optimization of processing conditions was obtained by mathematical model analysis.

DOI： 10.9773/sosei.51.455

CiNii Books

J-GLOBAL

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society for Technology of Plasticity  

We have recently developed a novel processing method for enlarging the diameter of a hollow shaft locally through the combination of cyclic torsional load with axial compressive load. First, experiments were conducted under various processing conditions to measure the deformation in the part with an enlarged diameter. Next, numerical simulation was performed using the finite element method to investigate the distributions of stress and strain in the processed part. The effects of axial-compressive load and twist angle on deformation behavior in the enlarged part were characterized through the above experiment and analysis. In addition, the cracking mechanism in the processed part was also investigated.

DOI： 10.9773/sosei.51.331

CiNii Books

researchmap

その他リンク： https://jlc.jst.go.jp/DN/JALC/00350376190?from=CiNii

記述言語：日本語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：The Japan Society for Technology of Plasticity  

We have recently developed a novel processing method for enlarging the diameter of a hollow shaft locally through the combination of cyclic torsional load with axial compressive load. First, experiments were conducted under various processing conditions to measure the deformation in the part with an enlarged diameter. Next, numerical simulation was performed using the finite element method to investigate the distributions of stress and strain in the processed part. The effects of axial-compressive load and twist angle on deformation behavior in the enlarged part were characterized through the above experiment and analysis. In addition, the cracking mechanism in the processed part was also investigated.

DOI： 10.9773/sosei.51.331

CiNii Books

J-GLOBAL

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

This paper investigates fatigue strength and existence of mechanical damage experimentally and analytically. In particular, first, we carry out rotary bending fatigue tests and investigate fatigue strength for smooth specimens and specimen processed using the working method. Secondly, we measure Vickers hardness value to investigate strain hardening, and observe microstructure to investigate microstructure change in the diameter-enlargement part. Finally, we simulate stress and strain distribution in the processed part during the processing, using finite element method (FEM), and calculate stress concentration rate and plastic strain. And we predict the existence of mechanical damage in the processed part during the processing experimentally and numerical-analytically. The results of the experiments and analyses indicate that the fatigue damage is not generated in the processed part during the processing in the discussed range of the diameter-enlargement rate D/D 0<1.8, through comparing with the smooth specimens. © 2010 SPIE.

DOI： 10.1117/12.851963

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

This paper investigates fatigue strength and existence of mechanical damage experimentally and analytically. In particular, first, we carry out rotary bending fatigue tests and investigate fatigue strength for smooth specimens and specimen processed using the working method. Secondly, we measure Vickers hardness value to investigate strain hardening, and observe microstructure to investigate microstructure change in the diameter-enlargement part. Finally, we simulate stress and strain distribution in the processed part during the processing, using finite element method (FEM), and calculate stress concentration rate and plastic strain. And we predict the existence of mechanical damage in the processed part during the processing experimentally and numerical-analytically. The results of the experiments and analyses indicate that the fatigue damage is not generated in the processed part during the processing in the discussed range of the diameter-enlargement rate D/D 0<1.8, through comparing with the smooth specimens. © 2010 SPIE.

DOI： 10.1117/12.851963

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

The strength reliability of the ceramics/metal joints in the vacuum interrupters was studied focusing on the thermal stress around the ceramics/metal joints due to mismatch of thermal expansion coefficients between ceramics and metal. It was found from the experiment results that the residual strength of the joint depends on the amount of metal brazing alloy used as a jointing material. Firstly, in the present work, the thermal stress around the ceramics/metal joints was calculated using finite element analysis. Next, the effect of the amount of metal brazing alloy on the residual strength of the joint was investigated on the basis of a fracture mechanical approach. Finally, the amount of metal brazing alloy minimizing the strength reduction of the joint is determined using the results of the numerical analysis.

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

The connecting work method to fix tightly a shaft in the central hole of a circle-plate was developed for application of axial enlarging processing. This method was successfully applied for connecting tightly two pieces of different material parts such as a circle-plate and a shaft. Because of performing at room temperature without either heating or cooling, this work method was clarified to be in high performance from point view of industrial uses.

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society of Mechanical Engineers  

Stress distributions beneath the contact surface of ceramic plat in contact with round bar were analyzed by 3-D FEM. On the basis of analytical results, the contact strength was evaluated by considering varied sizes and positions of pre-existing defects from a viewpoint of fracture mechanics. The contact rupture occurs from a surface defect that pre-exists in the vicinity of the edge of the plate. If we posit the premise that a defect size and a distance from contact boundary to its defect, the contact rapture load can be evaluated by using the proposed equation.

DOI： 10.1299/jmmp.1.490

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

The basic investigation was conducted for the diameter enlarging machine of a shaft by repeating cyclic torsion newly developed as a novel idea. With a concept repeating the alternate cyclic stress on a shaft subjected to axial-compressive force, the plastic working method to cause diameter enlarging deformation on a part of shaft was proposed. In this investigation, the diameter enlarging experiment and the model analysis by FEM with notice of the deformation behaviors on diameter enlarging process were conducted as axial-compressive stress sigma(c), and torsion angle 0 for mild steel pipes of SGD400. About 300cycles of cyclic torsion was repeated the cyclic torsion angle theta=3 degrees as a standard process condition to a shaft subjected to axial-compressive stress of sigma(c)/sigma(y0) =1.0. In this condition, the shaft has enlarged to about 1.3 times of initial diameter (D/D-0=1.3). The experimental value was in excellent agreement with the analysis value. Also, not only diameter enlarging deformation behaviors but also influence of machining conditions on the behaviors was clarified.

Web of Science

Scopus

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：ASME-AMER SOC MECHANICAL ENG  

To minimize surgical stresses including blood loss and operation time to the patients during hepatic resection, we studied the feasibility of a combination of a partial liver freezing technique and shape-memory alloy, which also enables a free-designed resection curve. In this surgical procedure, the region surrounding a tumor in the liver is frozen to excise and prevent hemorrhage. The liver was frozen by a Peltier module. The effects of cooling rate and freezing temperature on the excision force that arise between a scalpel and the liver are carried out experimentally as a basic research for partial freezing surgical procedures. A porcine liver was used as a liver sample. The physical properties were estimated by using the finite element method based on the heat transfer characteristics of the liver. Isolation of the liver was conducted using a scalpel attached to the end-effector of a 3 degrees of freedom robot. In the experiments, the minimum excision force was obtained at a temperature between 272 K and 275 K; therefore, it is preferable that the liver be excised within this temperature range. Lowering of the cooling rate decreases the excision force even if the temperature of the liver remains unchanged. The lower the temperature of the liver is, the larger the increment rate of excision force is with regard to the cooling rate.

DOI： 10.1115/1.2244577

Web of Science

PubMed

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

In the present works effective application of partial preheating by high frequency induction to enlarge the partial diameter of middle carbon steel was experimentally investigated. The partial reheating was carried out by varying preheating times under the same electric power conditions. As all other conditions other than temperature remained constant during the diameter enlargement experiments, the partial preheating effects were clarified to be estimative using a parameter of the sigma/sigma(gamma), which was found to be dependent on temperature regardless of constant compressive axial stress. For heating times of less than 50 sec. the preheating effect for promoting partial diameter-enlargement did not appear. In fact the reverse effect appeared in times ranging from 30 sec to 50 sec due to blue brittleness generated at temperatures from about 523K to about 623K. Also, low cycle fatigue cracks must be avoided when initiating at the filet end of an enlarged shaft while passing through the temperature range of blue brittleness during the cooling process. Therefore, the preheating temperature found to be most effective for promoting the diameter enlargement was greater than about 856K so as to increase easily the D-f/D-0 to above 2 times without generating damage cracks from fatigue.

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

A novel processing method to enlarge a partial diameter in the middle of shaft by means of combining a rotational-bending stress and an axial-compressive stress, can work various kinds of structural carbon steel without temperature-rise above 20K at room temperature. However, it was found that the maximum diameter-enlargement rate D-f/D-0 without initiating a fatigue damage crack decreased with increase in carbon contents of steel with mixed microstructure of ferrite and pearlite. It is thought that the mixed microstructure causes initiating the fatigue damage crack. In the present research, six kinds of heat-treatments of 823K-948Kx5.4ks-tempering after 1153Kx7.2ks-quenching were conducted for carbon steel shafts. The heat-treatments with change from mixed microstructure to uniform minute microstructures, are useful in increasing the diameter-enlargement rate D-f*/D-0.

Web of Science

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：The Japan Society for Technology of Plasticity  

A novel processing method was proposed to enlarge the partial diameter in the middle of a round bar with a diameter of &lt;i&gt;D&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt;=10mm. This method is called the collar-forming processing method. In order to study the conditions under which this processing method can be applied to shafts with practical diameters of &lt;i&gt;D&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt;=25mm-40mm for general industrial machines, the processing experiments were carried out under various processing conditions, such as normalized axial-compressive stress σ&lt;sub&gt;c&lt;/sub&gt;/σ&lt;sub&gt;y&lt;/sub&gt; and bending angle &lt;i&gt;θ&lt;/i&gt;. The results obtained are summarized as follows: the collar-forming process can be smoothly performed by selecting the initial interval &lt;i&gt;L&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt; between zippers within the range of 32mm-62mm, according to both the size of &lt;i&gt;D&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt; and the curvature radius &lt;i&gt;ρ&lt;/i&gt; of the zipper ends; the cycle parameter &lt;i&gt;N&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt;, which is used to determine the necessary rotation number &lt;i&gt;N&lt;/i&gt; for final collar size in a model equation, can be estimated from both (&lt;i&gt;ρ&lt;/i&gt;, &lt;i&gt;D&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt;) and (&lt;i&gt;θ&lt;/i&gt;, σ&lt;sub&gt;c&lt;/sub&gt;/σ&lt;sub&gt;y&lt;/sub&gt;); the deformation behaviors in the radial direction also depend on (&lt;i&gt;ρ&lt;/i&gt;, &lt;i&gt;D&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt;) as well as (&lt;i&gt;θ&lt;/i&gt;, σ&lt;sub&gt;c&lt;/sub&gt;/σ&lt;sub&gt;y&lt;/sub&gt;) and can be estimated from the function of &lt;i&gt;ρ&lt;/i&gt;/&lt;i&gt;D&lt;/i&gt;&lt;sub&gt;0&lt;/sub&gt; depending on bending angle &lt;i&gt;θ&lt;/i&gt;; the necessary rotation number &lt;i&gt;N&lt;/i&gt; has the tendency to increase with an increase in &lt;i&gt;ω&lt;/i&gt; in the case of larger diameter.

DOI： 10.9773/sosei.47.49

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

This paper deals with seismic characteristics of the single-stage bellows of Ti-Ni shape memory alloys, which are proposed as a new type of seismic elements. The single-stage bellows of different shapes are formed with the rubber bulge method and prepared for the dynamic tests. Tension-compression cyclic tests are carried out with increasing the displacement amplitude for them. Their effective stiffness and equivalent damping are standardized and estimated from the cyclic loops. Then the effects of bellows shape on dynamic properties are clarified. It is showed that nominal secant stiffness (effective stiffness) is strongly associated with shape factor H/Lw (H: bulge height, L_w: bulge width) of a single-stage bellows and that it can be expressed as a function of the coefficient of stiffness concerning the bulge shape and the material's stress strain characteristic.

DOI： 10.1299/jsmemecjo.2006.1.0_585

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Diameter-enlargement works that can form local enlarged diameter in short time at ordinary room temperature and by adding the axial compact force, and adding the rotation and the bend at the midpoint of constant diameter shaft is a new plastic deformation method that has superiority in saving resource, energy saving and mild environment. In order to decrease manufacture cost and expand application of Diameter-Enlargement work, we developed a new working method that can form multiple enlarged shafts by Diameter-Enlargement works. In present investigation we made a survey for the deformation behavior during working process of multiple enlarged shafts based on this method and made an equation modeling for the deformation behavior.

DOI： 10.1299/jsmemecjo.2006.1.0_349

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

In this research, we did thermal cycle test, four point bend test, and the simulation analysis by finite element method (FEM) to DBC and AMC semiconductor substrate. We examined influence of thermal-residual stress on the life reliability of the substrates, and did the basic research for establishing a profitable strength evaluation method through the comparison with the two kinds of joint methods. It is clarified that the AMC substrate is more excellent than the DBC substrate from the viewpoint of strength and the longevity reliability of the semiconductor substrate.

DOI： 10.1299/jsmemecjo.2006.6.0_221

CiNii Books

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

An actual joint structure of ceramics-metal in the airtight seal parts for a neutron detector was studied on the residual stress generated in the joint process due to the difference of the thermal expansion coefficient between ceramics and metal. The influences of shape and dimension of the joint structure on the residual stress were clarified analytically by finite element method (FEM) and verified experimentally by checking cracks generated in prototype samples. Based on fracture mechanics, equivalent stress intensity factor K_&lt;Ieq&gt; was calculated in consideration of a latent flaw in the residual stress fields, and optimal geometries of the joint structure were proposed for reducing the residual stress. The residual joint strength was discussed by using the difference Δ_&lt;Ieq&gt; between fracture toughness K_&lt;IC&gt; and K_&lt;Ieq&gt;. The main results obtained are summarized as follows : the residual joint stress increases with the thickness of a Cu-Ti eutectic reaction layer; the residual joint stress decreases with the reduction in taper angle of the end of Cu interlayer; the residual joint stress is hardly influenced by wall thickness in the end of SUS304 pipe. On the basis of these results, the optimization in the structural factors can decrease the residual stress because of reducing stress concentration field near the interface of ceramic and metal, and so the residual joint strength increase with decreasing of the residual stress depending in the structural factors as the thickness of a Cu-Ti eutectic reaction layer, taper angle of the end of Cu interlayer and wall thickness in the end of SUS304 pipe.

DOI： 10.2472/jsms.54.741

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本塑性加工学会  

CiNii Books

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本塑性加工学会  

CiNii Books

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人溶接学会  

Active metal brazing of ceramic to metal has been applied to the fabrication of advanced airtight seals for LPRMs(Local Power Range Monitors) used in BWRs(Boiling Water Reactors) to improve their life and reliability. Silicon nitride was selected as the ceramic part of the joint because of its superior swelling resistance. A cone-shaped silicon nitride and a copper interlayer were employed to join them to stainless steel parts. The effect of the copper-interlayer shape on the residual stress was studied. The relation between mechanical properties of the silicon nitride and tensile strength of the joints was also evaluated. It turned out that the copper interlayer design had significant effects on the residual stress of the joints. It was also found that the tensile strength of the joints was remarkably dependent on fracture toughness of the silicon nitride. Based on these results, the tensile strength change of the joints during neutron irradiation was studied and a life of the seal parts was discussed. Fifty years are obtained for the initial fracture toughness 5.4 MPa・m^&lt;1/2&gt; silicon nitride and 25 years for that of 4.4 MPa・m^&lt;1/2&gt; silicon nitride. Therefore the life period of the seal parts using silicon nitride that has initial fracture toughness 4.6-5.9 MPa・m^&lt;1/2&gt; is predicted to be between 25 and 50 years. It is more reliable seal parts comparison to the conventional seal parts used currently applying alumina ceramics as the ceramic part of the joint.

DOI： 10.2207/qjjws.23.88

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：JAPAN WELDING SOCIETY  

Active metal brazing of ceramic to metal has been applied to the fabrication of advanced airtight seals for LPRMs(Local Power Range Monitors) used in BWRs(Boiling Water Reactors) to improve their life and reliability.&lt;br&gt;Silicon nitride was selected as the ceramic part of the joint because of its superior swelling resistance. A cone-shaped silicon nitride and a copper interlayer were employed to join them to stainless steel parts.&lt;br&gt;The effect of the copper-interlayer shape on the residual stress was studied. The relation between mechanical properties of the silicon nitride and tensile strength of the joints was also evaluated. It turned out that the copper interlayer design had significant effects on the residual stress of the joints. It was also found that the tensile strength of the joints was remarkably dependent on fracture toughness of the silicon nitride. Based on these results, the tensile strength change of the joints during neutron irradiation was studied and a life of the seal parts was discussed. Fifty years are obtained for the initial fracture toughness 5.4 MPa·m&lt;sup&gt;1/2&lt;/sup&gt; silicon nitride and 25 years for that of 4.4 MPa·m&lt;sup&gt;1/2&lt;/sup&gt; silicon nitride. Therefore the life period of the seal parts using silicon nitride that has initial fracture toughness 4.6-5.9 MPa·m&lt;sup&gt;1/2&lt;/sup&gt; is predicted to be between 25 and 50 years. It is more reliable seal parts comparison to the conventional seal parts used currently applying alumina ceramics as the ceramic part of the joint.

DOI： 10.2207/qjjws.23.88

Scopus

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

Effective application of partial preheating by high frequency induction to enlarge the partial diameter of middle carbon steel was experimentally investigated. The partial preheating was carried out by varying preheating times under the same electric power conditions. As all other conditions other than temperature remained constant during the diameter enlarging experiments, the partial preheating effects were clarified to be estimative using a parameter of the σ/σ_y, where σ_y was dependent on temperature. For preheating times of less than 50 sec, the preheating effect for promoting partial diameter-enlargement did not appear due to blue brittleness influences. For preheating times of less than 110 sec, the preheating temperature was greater than about 856K and was most effective for promoting the diameter enlargement to increase easily the D_f/D_0 to above 2 times without generating damage cracks from fatigue.

DOI： 10.1299/jsmemecjo.2005.1.0_633

CiNii Books

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：TRANS TECH PUBLICATIONS LTD  

A novel processing method was proposed to enlarge a partial diameter in the middle of a round bar with an experimental size of 10mm. in diameter. To confirm that the processing method is applicable also to shaft with a practical size of 25mm-60mm in diameter for general industrial machine, a large-scale processing machine was developed. Deformation behavior of diameter in a processed part during processing process was made to an expression. The several influences, such as bending angle theta, axial-compressive stress sigma(c), diameters D-0, rotation number N of shaft and curvature radius p, on the increase behavior of diameter were estimated quantitatively.

Web of Science

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本塑性加工学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：愛媛大学  

Fracture mechanics based considerations were made for investigating the ring-crack formation of ceramic plates contacted with a ceramic sphere under a combined normal and tangential indentation load. The intrnsic tensile strength of the ceramic plate did not dictate the onset of ring-crack formation. The size of pre-existing defects (being less than one micron) that may result in the ring-crack initiation were somwhat smaller than the grain size of the ceramic plate. On the other hand, the stress gradient induced beneath the contact was significantly dependent on the contact angle of normal/tangential combined load; when the contact angle is increased, the mean dimension of defects which lead to ring-crack initiation becomes large, whereas the location of the induced crack is progressively away of the contact circle. The stress gradient induced beneath the contact was taken into account for calculating the stress intensity factor of the pre-existing surface defect. The fracture toughness value thus estimated for the ceramic plates satisfactorily predicted the onset of ring-crack formation of all the ceramic plates examined.

CiNii Books

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本塑性加工学会  

CiNii Books

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

Fracture mechanics based considerations were made for investigating the ring-crack formation of ceramic plates contacted with a ceramic sphere under a combined normal and tangential indentation load. The intrnsic tensile strength of the ceramic plate did not dictate the onset of ring-crack formation. The size of pre-existing defects (being less than one micron) that may result in the ring-crack initiation were somwhat smaller than the grain size of the ceramic plate. On the other hand, the stress gradient induced beneath the contact was significantly dependent on the contact angle of normal/tangential combined load; when the contact angle is increased, the mean dimension of defects which lead to ring-crack initiation becomes large, whereas the location of the induced crack is progressively away of the contact circle. The stress gradient induced beneath the contact was taken into account for calculating the stress intensity factor of the pre-existing surface defect. The fracture toughness value thus estimated for the ceramic plates satisfactorily predicted the onset of ring-crack formation of all the ceramic plates examined.

DOI： 10.2472/jsms.53.1149

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：日本塑性加工学会  

CiNii Books

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：BLACKWELL PUBLISHING LTD  

Residual stresses generated by the mismatch of thermal expansion coefficients of ceramics and metals affect the strength of ceramic-metal joints. An interlayer metal can be inserted between the ceramic and metal in order to relax this stress. An analysis was carried out of the residual stresses produced during joint-cooling and in 4-point bending tests. The effects of interlayer thickness on ceramic-metal joint strength were then studied by considering a superimposed stress distribution of the residual stress and the bending stress. Finally, joint strength was estimated from fracture mechanics and strength probability analysis by considering the residual stress distribution, defect size and position of pre-existing defects in the ceramic parts. As a result of this study, we suggest an optimum material selection and interlayer thickness for ceramic-metal joint structures. This approach is generally suitable for the design of electrical and mechanical structures.

DOI： 10.1046/j.1460-2695.2003.00581.x

Web of Science

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

DOI： 10.1299/jsmezairiki.2003.0_697

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

In this research, packaging structures in which chip parts were bonded to the ceramics substrate of Alumina (Al_2O_3) or nitride aluminum (AIN) with electro-conductive adhesive etc. through a thick film conducting electricity, was studied. For the structures, the bonding remaining strength, considered the residual stress caused in a bonding process based on fracture mechanics, was evaluated, and the influences of both the ceramics substrate and the thick film conductor's thermo-physical property on the strength were examined. Moreover, to examine the decrease behavior of the bonding residual strength by heat cycle loads in-service, thermal cycle tests, the verification tests of a peeling strength, and the simulation analyses of those tests were done, and the peeling fracture strength and the fracture life were predicted. As a result, the mechanism of trouble generated in-service is clarified from the viewpoint of fracture mechanics, the validity of remedies is confirmed, and the present research is useful for the new development of the product.

DOI： 10.1299/jsmemecjo.2003.1.0_315

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

We have found a new plastic working method by which an arbitrary size collar can be formed in the middle of a round mild steel bar of φ10 in diameter at room temperature only with rising in temperature below 10℃. This unique plastic working method is carried out by giving the round bar repeatedly an alternate stress of tension and compression by a rotational bending moment under a constant axial-compressive stress below the yield strength. The plastic deforming behavior in the working process are possible to be predicted by the model formula with only a parameter which we have considered in original idea. In the purpose of developing this working method into a various steel bar with various yield strength, 6 kinds of structural steel with φ10 in diameter were collar-formed to clarified the effect of yield strength on the working conditions. The model formula to estimate the deforming behaviors was revised so that the effects of yield strength on diameter enlarging deformation behaviors could be considered into the condition of compressive stress.

DOI： 10.1299/jsmemecjo.2003.1.0_441

CiNii Books

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

It is essential to determine the shape/dimension of shape memory alloy (SMA) before heating that the elastic recovery properties in the process of unloading changes with increasing the maximum strain in the process of loading. Therefore, in this paper, the formula-model was offered for behavior of elastic recovery and was identified by inverse analysis based on series combined model. The average young's modulus was estimated from each modeling formula, respectively.

DOI： 10.1299/jsmemecjo.2003.1.0_279

CiNii Books

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：SOC MATERIALS SCIENCE, JAPAN  

Residual stress generated by thermal expansion coefficient mismatch between ceramic and metal is an important problem affecting the strength of ceramic-metal joints. An interlayer, which is a ductile metal, is often inserted between ceramic and metal in order to relax this residual stress. In this study, the residual stress produced in the joint-cooling process is analyzed and 4-point bending tests are carried out. From the viewpoint of experimental observations and fracture mechanics, the effects of interlayer thickness on joint strength in ceramic/metal joints are discussed considering the superimposed stress distribution of the residual stress and the bending stress. Joint strength is then estimated based on fracture mechanics and fracture probability considering the superimposed stress, crack size and position of pre-existing defects in the ceramics. The optimum interlayer thickness for the present specimen is identified, and the estimation method is extended to the analysis of generic joint strength using normalized strength of ceramic by expressing joint strength in terms of normalized strength considering the scatter of joint strength and the effective volume.

DOI： 10.2472/jsms.51.9Appendix_109

Web of Science

Scopus

researchmap

researchmap

researchmap

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The ceramics/metal joints in the airtight seal parts for a neutron detector are studied on the reliability for strength and long-term life. Both functions of airtight and insulation are required for the airtight seal parts, which suffer a very bad influence from a viewpoint of long-term reliability as well as strength, because the residual stress is generated in these joints due to the difference of the thermal expansion coefficient between ceramics and metal. The ceramics subjected to neutron irradiation in-serve occurs in swelling (volume expansion) and decreases in strength. Moreover, the copper interlayer rises in yield stress and hardens with increasing the plastic deformation due to the swelling of ceramics, and so lowers in function for stress relaxation. As a result, not only the internal stress in ceramics increases with passing the time in service, but also the facture strength of ceramics lowers, and finally a delayed fracture occurs at the ceramic/metal joints in the airtight seal parts. Therefore, in our study, the residual stress has been analyzed by a simulation model using FEM, so that both mechanisms of the increment in internal stress as well as mechanical damage can be clarified for the ceramic/metal jointing parts subjected to the neutron irradiation over long-term. On the other hand, the strength verification against the ceramic/metal joints are performed through simulation model analyses as well as the virtual tensile tests for small mock up specimens. From a viewpoint of fracture mechanics, the reliability for fracture life as well as strength of the airtight seal parts is discussed statistically considering the scatter of strength for Si3N4. Key words: Ceramics/Metal Joints, Mechanical Damage, Strength Reliability, Neutron Irradiation, Residual Stress, Swelling, hardening, Fracture toughness, Fracture Life. © 2002, The Society of Materials Science, Japan. All rights reserved.

DOI： 10.2472/jsms.51.9Appendix_101

Scopus

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

DOI： 10.1299/jsmezairiki.2002.0_253

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：社団法人日本材料学会  

The residual stress, which generated by thermal expansion coefficient mismatch between ceramics and metals, is an important problem on strength in ceramic/metal joints. An interlayer, which is a ductile metal, is inserted between ceramics and metal in order to relax the residual stress. In this study, first of all, the analysis of the residual stress produced in joint-cooling process and 4-point bending tests were carried out. Next, from a viewpoint of experimental and fracture mechanics, the effects of interlayer thickness on joint strength in ceramic/metal joints were discussed considering the superposed stress distribution of the residual stress and the bending stress. In addition, the estimation of joint strength was tried to do from viewpoints of fracture mechanics and probability of strength by considering the superposed stress, size and position of potential defects in the ceramics. From the above-mentioned, it is found that the optimum thickness is 0.2mm in this specimen. Joint strength in various interlayer thicknesses can be estimated as normalized strength of ceramics by arranging joint strength to normalized strength considering the scatter of joint strength and the effective volume.

DOI： 10.2472/jsms.50.7

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：JAPAN INST METALS  

We have proposed a new collar-forming technology of repeating an alternate stress of tension. and compression by rotary bending against a round bar subjected to a constant axial- compressive load(1),2)) As an application and development of this technology, a new cold working for bellows-forming in a pipe has bow developed and applied to the mild steel pipe of 10 mm in diameter and 2 mm in thickness, and also to the stainless steel pipe of 16 ran in diameter and 1 mm in thickness.
In this research a calculation model is made to estimate the deformation variation m the bellows-forming process for tubing materials. The bellows-forming conditions (such as bending angle and axial-compressive stress, etc) are clarified by an inverse analysis against experimental data, it is clarified that a large plastic deformation with superplasticity-like behaviors progresses only with slight temperature-rise below 15 K. Furthermore, the bellows- forming deformation variation and the decision conditions of the final shape and the size are estimated theoretically.

Web of Science

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：JAPAN INST METALS  

We have developed a now technology of cold working by which a collar can be formed in the middle of a round mild steel bat Keeping a constant axial-compressive stress about the yield strength of the material used, giving the round bar repeatedly an alternate stress of tension and compression by a bending moment, the local collar is formed in the round bar in the process of superplasticity-like deformation advances. One of the merits for this processing method is to obtain a superplasticity-like compressive deformation by a lower compressive load without the mechanical damage produced by strain accumulation. Another is to rise only within 15 K in temperature on the collar in the processing regardless of the presence of lubricant. The third is to prevent materials from being wasted due to die cutting work Therefore, this technology of cold working leads to the saving of both energy and resource and to the prevention of environmental pollution due to lubricant. Through this study, the processing conditions that have a large influence on the collar-forming processing are clarified by means of the experiment and the calculation model analysis. Moreover, the temperature change in the collar is measured by an infrared thermometer along with the superplasticity-like deformation in this collar-forming processing.

Web of Science

researchmap

researchmap

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

It was found out that a local collar could be formed on a rod by a combination of compression, bending and axial-rotation temperature rise in collar forming process was below 15℃ in spite of super plastic deformation. This collar forming method is a technology that Baushinger effect can be applied to form collars by giving altemate bending stress of tension and compression to a rod subjected to axial stress slightly below yield strength.

DOI： 10.1299/jsmezairiki.2001.0_367

CiNii Books

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Society of Materials Science Japan  

The residual stress, which generated by thermal expansion coefficient mismatch between ceramics and metals, is an important problem on strength in ceramic/metal joints. An interlayer, which is a ductile metal, is inserted between ceramics and metal in order to relax the residual stress. In this study, first of all, the analysis of the residual stress produced in joint-cooling process and 4-point bending tests were carried out. Next, from a viewpoint of experimental and fracture mechanics, the effects of interlayer thickness on joint strength in ceramic/metal joints were discussed considering the superposed stress distribution of the residual stress and the bending stress. In addition, the estimation of joint strength was tried to do from viewpoints of fracture mechanics and probability of strength by considering the superposed stress, size and position of potential defects in the ceramics. From the above-mentioned, it is found that the optimum thickness is 0.2mm in this specimen. Joint strength in various interlayer thicknesses can be estimated as normalized strength of ceramics by arranging joint strength to normalized strength considering the scatter of joint strength and the effective volume.

DOI： 10.2472/jsms.50.7

Scopus

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

DOI： 10.1299/jsmezairiki.2001.0_363

CiNii Books

researchmap

researchmap

researchmap

researchmap

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：JAPAN INST METALS  

The present authors have found experimentally the phenomenon that even ordinary polycrystalline metal materials such as the mild steel, copper and so on, can reveal the superplasticity-like deformation at room temperature by controlling mechanical conditions. We have found a plastic forming method by which a collar can be formed in the middle of a round mild steel bar. Keeping a constant axial-compressive stress about the yield strength of the material used in the round bar, giving the round bar repeatedly an alternate stress of tension and compression by bending moment, the local collar is formed in the round bar in the process of superplasticity-like deformation advances. The collar can be cut into gears or be used to fix a gear on shaft as a boss. We call this cold working based on the new concept technology a collar-forming method. In this research, a calculation model and a deformation mechanism model are made for the deformation variations in a round bar subjected to an alternate stress of tension and compression produced by a bending moment and an axial-compressive stress about the yield stress or the material used. The parameters that dominate the deformation are investigated by means of the experiment and the model analysis. Moreover temperature changes along with the superplasticity-like deformation are measured by an infrared thermometer and compared with the model analysis results.

Web of Science

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

DOI： 10.1299/jsmezairiki.2000.0_381

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：愛媛大学工学部  

CiNii Books

researchmap

researchmap

researchmap

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

A simple analysis method was developed by making well use of finite element method(FEM)program for general purposes.The temperature dependence of mechanical properties for every material consisting of ceramic/metal jointing was considered in this method.Using this method, the residual stresses producing during the jointing process were analyzed for Si_3N_4/SUS304 joints with the insert layer of Cu made by an active metal brazing (Ti-Ag-Cu)method so as to clarify the residual stress behavior due to the creep of Cu.The equivalent normal stress calculated from the multi-axial stress was used to evaluate the strength of fracture which resulted from initial flaws existing in the ceramic side.From the analytical results, it is found that the temperature at which the residual stress begins to generate is about 550℃, and it is clarified that the creep of Cu layer during cooling process may relax the residual stress in ceramics side and can not be neglected for the estimation of ceramic fracture due to residual stress.

DOI： 10.2472/jsms.49.461

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Society of Materials Science Japan  

A simple analysis method was developed by making well use of finite element method (FEM) program for general purposes. The temperature dependence of mechanical properties for every material consisting of ceramic/metal jointing was considered in this method. Using this method, the residual stresses producing during the jointing process were analyzed for Si3N4/SUS304 joints with the insert layer of Cu made by an active metal brazing (Ti-Ag-Cu) method so as to clarify the residual stress behavior due to the creep of Cu. The equivalent normal stress calculated from the multi-axial stresses was used to evaluate the strength of fracture which resulted from initial flaws existing in the ceramic side. From the analytical results, it is found that the temperature at which the residual stress begins to generate is about 550 °C , and it is clarified that the creep of Cu layer during cooling process may relax the residual stress in ceramics side and can not be neglected for the estimation of ceramic fracture due to residual stress.

DOI： 10.2472/jsms.49.461

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

A major problem in ceramic/metal joint is thermal expansion coefficient mismatch between ceramics and metal. This thermal expansion coefficient mismatch causes serious residual stresses at the interface of the ceramic/metal joint, which generated during joint-cooling process. Then, an interlayer, which is ductile metal such as copper, nickel and so on, is inserted between ceramics and metal because of relaxing the residual stress. It should be considered that thickness of interlayer have significant influence on the joint strength with considering the residual stress. In this study, it paid attention to the thickness of interlayer, and the optimum thickness of interlayer was discussed from a viewpoint of the stresses based on simulation model analysis as well as 4 point bending tests, considering the residual stresses, which were analyzed using three-dimensional plasto-elastic finite element method. As a result of the analysis, residual stress increased with decreasing of the interlayer thickness. The superposing stress of the applied bending stress and the residual stress showed minimum value in the case of the interlayer thickness of 0.2mm. On the other hand, paying notice to the result of the bending test as well as the analysis, the joint specimen showed the highest bending strength in the case of the interlayer thickness of 0.2mm. Furthermore, the scatter of joint strength is apparently small in this thickness compared with in the other thickness.

DOI： 10.2472/jsms.49.905

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2472/jsms.49.905

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Soc Mater Sci, Japan  

A major problem in ceramic/metal joint is thermal expansion coefficient mismatch between ceramics and metal. This thermal expansion coefficient mismatch causes serious residual stresses at the interface of the ceramic/metal joint, which generated during joint-cooling process. Then, an interlayer, which is ductile metal such as copper, nickel and so on, is inserted between ceramics and metal because of relaxing the residual stress. It should be considered that thickness of interlayer have significant influence on the joint strength with considering the residual stress. In this study, it paid attention to the thickness of interlayer, and the optimum thickness of interlayer was discussed from a viewpoint of the stresses based on simulation model analysis as well as 4 point bending tests, considering the residual stresses, which were analyzed using three-dimensional plasto-elastic finite element method. As a result of the analysis, residual stress increased with decreasing of the interlayer thickness. The superposing stress of the applied bending stress and the residual stress showed minimum value in the case of the interlayer thickness of 0.2 mm. On the other hand, paying notice to the result of the bending test as well as the analysis, the joint specimen showed the highest bending strength in the case of the interlayer thickness of 0.2 mm. Furthermore, the scatter of joint strength is apparently small in this thickness compared with in the other thickness.

DOI： 10.2472/jsms.49.905

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：社団法人日本材料学会  

Cyclic tensile fatigue tests were conducted for Si_3N_4/S45C joint specimens with copper interlayer at room temperature in order to clarify fatigue strength properties of ceramic/metal joint, considering the influence of residual stress in ceramics induced during joining process. Not only the joining process residual stress but also the residual stress behavior due to cyclic tensile loading was analyzed by using the three-dimensional elastic-plastic finite-element method. All experimental data obtained in this study were tried to arrange as the relationship between the normalized testing stress and the effective loading time by using the unified estimation method with considering effective volume and effective loading time. However, even if using the unified estimation method, the normalized strengths in the cyclic fatigue tests were clearly lower than normalized tensile strength at fracture probability of 50%. The difference of both normalized strengths was caused by the increase of the residual stress redistributed during cyclic fatigue tests. The redistributed residual stress was due to the reversible plastic deformation made in the interlayer of copper, but tended to saturate after second cycles. Then, if modifying not only the effective loading time but also the time-strength by using the unified estimation method against the superposing stress of the testing stress and the redistributing residual stress in cyclic fatigue tests, the cyclic tensile fatigue strengths agreed well with the normalized tensile strength for ceramic/metal joints as well as for monolithic ceramics. All cyclic fatigue strengths containing tensile fracture strength can be estimated well as the normalized strength with scatter properties of Weibull distribution.

DOI： 10.2472/jsms.48.1416

Scopus

researchmap

researchmap

researchmap

記述言語：日本語   出版者・発行元：社団法人日本材料学会  

Room and high temperature four point bend tests for Si_3N_4/SUS_30_4 joints were carried out at various crosshead speeds. Ceramics/metal interface region and brazing zone were analyzed using a vickers hardness tester, SEM and EPMA to discuss the relation between strength of joints and microstructure. Furthermore, the fracture strength and the nature of its scatter were estimated based on the proposed model. Failure of brazed Si_3N_4/metal joints occurred at a flaw in ceramics near bonding interface. Therefore, the bending strength of the joints was dominated by a magnitude and distribution of stress concentration induced in ceramic region. The magnitude of stress concentration induced in ceramic region was dependent on deformation resistance of interlayer. This buffer effect of interlayer depended on exposed time of the specimen at test temperature, which inversely corresponds to loading rate. The dispersion of strengths of the joints was well described according to the weibull distribution using unified estimation method. The estimation equation was proposed to evaluate the bending strength and its nature of scatter.

DOI： 10.2472/jsms.48.1288

CiNii Books

researchmap

その他リンク： https://jlc.jst.go.jp/DN/JALC/00057897103?from=CiNii

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）   出版者・発行元：CHINA HIGHER EDUCATION PRESS BEIJING  

A elastic-plastic analysis of AlN/Cu jointing plate was performed by FEM to study the residual stress produced in the jointing-cooling process. This residual stress due to the difference of thermal expansion coefficient between ceramics and metal was analyzed, considering the thickness of extremely thin Al2O3 layer produced on the surface of AlN in order to promote oxidation reaction jointing. Also, 4-point bending tests and static fatigue tests were carried out at room temperature in atmosphere. The static fatigue strength and the fracture mechanism of the AlN/Cu semi-conductor plate were discussed from the viewpoint of fracture mechanics, considering the presence of initial defects in ceramics. A static fatigue life was estimated based on a stress intensity factor of the supper-posed stress of the residual stress and the bending stress in ceramics of AlN/Cu jointing plate with the various thickness of Al2O3 layer.

Web of Science

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.2472/jsms.48.1416

Scopus

researchmap

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Soc Mater Sci, Japan  

Cyclic tensile fatigue tests were conducted for Si3N4/S45C joint specimens with copper interlayer at room temperature in order to clarify fatigue strength properties of ceramic/metal joint, considering the influence of residual stress in ceramics induced during joining process. Not only the joining process residual stress but also the residual stress behavior due to cyclic tensile loading was analyzed by using the three-dimensional elastic-plastic finite-element method. All experimental data obtained in this study were tried to arrange as the relationship between the normalized testing stress and the effective loading time by using the unified estimation method with considering effective volume and effective loading time. However, even if using the unified estimation method, the normalized strengths in the cyclic fatigue tests were clearly lower than normalized tensile strength at fracture probability of 50%. The difference of both normalized strengths was caused by the increase of the residual stress redistributed during cyclic fatigue tests. The redistributed residual stress was due to the reversible plastic deformation made in the interlayer of copper, but tended to saturate after second cycles. Then, if modifying not only the effective loading time but also the time-strength by using the unified estimation method against the superposing stress of the testing stress and the redistributing residual stress in cyclic fatigue tests, the cyclic tensile fatigue strengths agreed well with the normalized tensile strength for ceramic/metal joints as well as for monolithic ceramics. All cyclic fatigue strengths containing tensile fracture strength can be estimated well as the normalized strength with scatter properties of Weibull distribution.

DOI： 10.2472/jsms.48.1416

Scopus

researchmap

© 2017 Trans Tech Publications, Switzerland. Diamond-like-carbon (DLC) films are promising as coating materials. Ion plating, an excellent method in terms of adhesiveness, step coverage, and deposition rate, can form not only pure metal films but also oxide films, nitride films, and carbonized films. In this study, which aimed to form a DLC film with good adhesiveness and a diamond crystal structure, a DLC film, with a SiC interlayer formed by ion plating with introduction of tetramethylsilane (TMS), was formed. It was experimentally revealed that as the interlayer thickness increases, the crystal structure in the DLC film becomes more diamond rich, and the adhesiveness of the DLC film and substrate is thereby improved.

DOI： 10.4028/www.scientific.net/KEM.749.70

Scopus

researchmap

© 2017 Trans Tech Publications, Switzerland. The most progress towards a practical method of fusing municipal waste incineration ash has been in the use of a plasma jet that employs arc discharge, a form of thermal plasma. However, a remaining problem is that stable plasma generation is prevented by melting of the nozzle of the plasma-jet torch by the high-Temperature plasma flow. With the objective of developing high-speed fusion treatment for waste materials using an in-liquid plasma jet, basic research was conducted on plasma stability and the durability of plasma-jet torches, including electrodes and nozzles. Basic plasma jet characteristics such as the discharge voltage, current, and power value at the time of plasma jet generation were investigated experimentally. The relationship between the temperature distribution near the tip of a plasma jet torch and electrode damage was investigated by fluid-heat coupled analysis using the finite element method.

DOI： 10.4028/www.scientific.net/KEM.749.76

Scopus

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

J-GLOBAL

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

To clarify the generating mechanism of the wrinkles on the surface of the test piece in a rotary draw bending forming, the processing experiment and the simulation analysis using finite element method (FEM) were done. The result of obtaining is as follows: the wrinkle is generated by not only curved part but also the straight run of the original pipe as the processing progresses; the frictional force between the pipe and bending die generates the wrinkle, and promotes the wrinkle generated in addition; the occurrence condition of the wrinkle depends on parameters other than frictional properties, because the wrinkle is generated even when the frictional force between the pipe and the die is disregarded.

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

In plastic forming, deformation resistance of a material is generically decreased by superimposed ultrasonic vibrations (UVs) as "Blaha effect". In order to clarify the mechanism of the stress decreasing, stress-strain/time behaviors were experimented by the compression tests that superimpose the UV with different amplitude voltages to fixed strain and constant deformation rate, and the UV to the ratio of different specimen diameter versus horn tip diameter. Stress decreasing rate was increased with increasing amplitude voltage and was increased with decreasing diameter ratio.

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

The strength reliability of the ceramics/metal joints in the vacuum interrupters was studied focusing on the thermal stress around the ceramics/metal joints due to mismatch of thermal expansion coefficients between ceramics and metal. It was found from the experiment results that the residual strength of the joint depends on the amount of metal brazing alloy used as a jointing material. Firstly, in the present work, the thermal stress around the ceramics/metal joints was calculated using finite element analysis. Next, the effect of the amount of metal brazing alloy on the residual strength of the joint was investigated on the basis of a fracture mechanical approach. Finally, the amount of metal brazing alloy minimizing the strength reduction of the joint is determined using the results of the numerical analysis.

Scopus

researchmap

記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

The connecting work method to fix tightly a shaft in the central hole of a circle-plate was developed for application of axial enlarging processing. This method was successfully applied for connecting tightly two pieces of different material parts such as a circle-plate and a shaft. Because of performing at room temperature without either heating or cooling, this work method was clarified to be in high performance from point view of industrial uses.

Scopus

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：英語   出版者・発行元：一般社団法人日本機械学会  

Stress distributions beneath the contact surface of ceramic plat in contact with round bar were analyzed by 3-D FEM. On the basis of analytical results, the contact strength was evaluated by considering varied sizes and positions of pre-existing defects from a viewpoint of fracture mechanics. The contact rupture occurs from a surface defect that pre-exists in the vicinity of the edge of the plate. If a defect size and a distance from contact boundary to its defect are assumed, the contact rapture load can be estimated by using the proposed equation.

CiNii Books

researchmap

記述言語：英語   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

In the present works effective application of partial preheating by high frequency induction to enlarge the partial diameter of middle carbon steel was experimentally investigated. The partial reheating was carried out by varying preheating times under the same electric power conditions. As all other conditions other than temperature remained constant during the diameter enlargement experiments, the partial preheating effects were clarified to be estimative using a parameter of the sigma/sigma(gamma), which was found to be dependent on temperature regardless of constant compressive axial stress. For heating times of less than 50 sec. the preheating effect for promoting partial diameter-enlargement did not appear. In fact the reverse effect appeared in times ranging from 30 sec to 50 sec due to blue brittleness generated at temperatures from about 523K to about 623K. Also, low cycle fatigue cracks must be avoided when initiating at the filet end of an enlarged shaft while passing through the temperature range of blue brittleness during the cooling process. Therefore, the preheating temperature found to be most effective for promoting the diameter enlargement was greater than about 856K so as to increase easily the D-f/D-0 to above 2 times without generating damage cracks from fatigue.

Web of Science

Scopus

researchmap

記述言語：英語   出版者・発行元：WORLD SCIENTIFIC PUBL CO PTE LTD  

A novel processing method to enlarge a partial diameter in the middle of shaft by means of combining a rotational-bending stress and an axial-compressive stress, can work various kinds of structural carbon steel without temperature-rise above 20K at room temperature. However, it was found that the maximum diameter-enlargement rate D-f/D-0 without initiating a fatigue damage crack decreased with increase in carbon contents of steel with mixed microstructure of ferrite and pearlite. It is thought that the mixed microstructure causes initiating the fatigue damage crack. In the present research, six kinds of heat-treatments of 823K-948Kx5.4ks-tempering after 1153Kx7.2ks-quenching were conducted for carbon steel shafts. The heat-treatments with change from mixed microstructure to uniform minute microstructures, are useful in increasing the diameter-enlargement rate D-f*/D-0.

Web of Science

Scopus

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

researchmap

We have proposed a new deformation processing method for enlarging partial diameter of shaft. The method is called a collar-forming method. To examine fatigue damage of the part processed (called a collar) during the forming process, rotary bending fatigue tests and tensile strength verification tests were carried out on smooth test specimen as well as two kinds of collared test specimen, namely the specimen with burrs and without burr. Moreover, stress concentration and strain hardening in the root of collar were quantitatively evaluated by the finite element method. The following were clarified from those results: Though there are burrs, the fatigue damage in the root of a collar during the forming process is not caused at all when an increase rate of shaft diameter is within 1.7. The processing stage in which the increase rate is within 1.7 is still a stage of the work hardening, and is not a stage in which the fatigue life is shortened by increasing of macro-damage. There are not any signs of fatigue deterioration in the root of collar formed by the processing method from a practical viewpoint, either but there is sound to the fatigue damage enough.

Scopus

researchmap

researchmap

記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：Society of Materials Science Japan  

Fracture mechanics based considerations were made for investigating the ring-crack formation of ceramic plates contacted with a ceramic sphere under a combined normal and tangential indentation load. The intrnsic tensile strength of the ceramic plate did not dictate the onset of ring-crack formation. The size of pre-existing defects (being less than one micron) that may result in the ring-crack initiation were somwhat smaller than the grain size of the ceramic plate. On the other hand, the stress gradient induced beneath the contact was significantly dependent on the contact angle of normal/tangential combined load
when the contact angle is increased, the mean dimension of defects which lead to ring-crack initiation becomes large, whereas the location of the induced crack is progressively away of the contact circle. The stress gradient induced beneath the contact was taken into account for calculating the stress intensity factor of the pre-existing surface defect. The fracture toughness value thus estimated for the ceramic plates satisfactorily predicted the onset of ring-crack formation of all the ceramic plates examined.

DOI： 10.2472/jsms.53.1149

Scopus

researchmap

記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

In this research, packaging structures in which chip parts were bonded to the ceramics substrate of Alumina (Al_2O_3) or nitride aluminum (AlN) with electro-conductive adhesive etc. through a thick film conducting electricity, was studied. For the structures, the bonding remaining strength, considered the residual stress caused in a bonding process based on fracture mechanics, was evaluated, and the influences of both the ceramics substrate and the thick film conductor's thermo-physical property on the strength were examined. Moreover, to examine the decrease behavior of the bonding residual strength by heat cycle loads in-service, thermal cycle tests, the verification tests of a peeling strength, and the simulation analyses of those tests were done, and the peeling fracture strength and the fracture life were predicted. As a result, the mechanism of trouble generated in-service is clarified from the viewpoint of fracture mechanics, the validity of remedies is confirmed, and the present research is useful for the new development of the product.

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

To execute surgical operations on livers in short time and to reduce the stress on the patients, we propose a soft freezing method for liver surgical procedures. In this surgical procedure, a tumor surrounding the liver is frozen in order to ease the excision and prevent hemorrhage. The effects of cooling velocity and freezing temperation on the excision force by the scalpel on the liver are carried out experimentally as a basic research into partial freezing surgical procedures. In this study, to excise a cancer using free excision curve, the development of the cooling needle and the investigation of the cooling function were carried out using a liver of a pig. The physical properties value was reversely analyzed by using the finite element method based on the heat transfer characteristic data of a mock liver. In addition, the proposed estimation equation can express the relation between arbitrary cooling time and distance and temperature.

DOI： 10.1299/jsmemecjo.2003.7.0_53

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人日本機械学会  

CiNii Books

researchmap

記述言語：英語   出版者・発行元：SOC MATERIALS SCIENCE, JAPAN  

The ceramics/metal joints in the airtight seal parts for a neutron detector are studied on the reliability for strength and long-term life. Both functions of airtight and insulation are required for the airtight seal parts, which suffer a very bad influence from a viewpoint of long-term reliability as well as strength, because the residual sum is generated in these joints due to die difference of the thermal expansion coefficient between ceramics and metal. The ceramics subjected to neutron irradiation in-serve occurs in swelling (volume expansion) and decreases in strength. Moreover, the copper interlayer rises in yield sum and hardens with increasing the plastic deformation due to the swelling of ceramics, and so lowers in function for stress relaxation. As a result, not only the internal stress in ceramics increases with passing the time in service, but also the facture strength of ceramics lowers, and finally a delayed fracture occurs at the ceramic/metal joints in the airtight seal parts. Therefore, in our study, the residual stress has been analyzed by a simulation model using FEM so that both mechanisms of the increment in internal stress as well as mechanical damage can be clarified for the ceramic/metal jointing parts subjected to the neutron irradiation over long-term. On the other hand, the strength verification against the ceramic/metal joints are performed through simulation model analyses as well as the virtual tensile tests for small mock up specimens. From a viewpoint of fracture mechanics, the reliability for fracture life as well as strength of the airtight seal parts is discussed statistically considering the scatter of strength for Si3N4.

Web of Science

Scopus

researchmap

記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

To execute surgical operations on livers in a short time and to reduce the stress on the patients, we propose a soft freezing method for liver surgical procedures. In this surgical procedure, a tumor surrounding the liver is frozen in order to ease the ease the excision and prevent hemorrhage. The effects of cooling velocity and freezing temperature on the excision force by the scalpel on the liver are carried out experimentally as a basic research into partial freezing surgical procedures. In this study, to excise a cancer using free excision curve, the development of the cooling needle and the investigation of the cooling function were carried out using a liver of a big. The physical properties value was reversely analyzed by using the finite element method based on the heat transfer characteristic data of a mock liver. In addition, the proposed estimation equation can express the relation between arbitrary cooling time and distance and temperature.

DOI： 10.1299/jsmemecjo.2002.6.0_15

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

CiNii Books

researchmap

記述言語：英語  

Residual stress generated by thermal expansion coefficient mismatch between ceramic and metal is an important problem affecting the strength of ceramic-metal joints. An interlayer, which is a ductile metal, is often inserted between ceramic and metal in order to relax this residual stress. In this study, the residual stress produced in the joint-cooling process is analyzed and 4-point bending tests are carried out. From the viewpoint of experimental observations and fracture mechanics, the effects of interlayer thickness on joint strength in ceramic/metal joints are discussed considering the superimposed stress distribution of the residual stress and the bending stress. Joint strength is then estimated based on fracture mechanics and fracture probability considering the superimposed stress, crack size and position of pre-existing defects in the ceramics. The optimum interlayer thickness for the present specimen is identified, and the estimation method is extended to the analysis of generic joint strength using normalized strength of ceramic by expressing joint strength in terms of normalized strength considering the scatter of joint strength and the effective volume. © 2002, The Society of Materials Science, Japan. All rights reserved.

DOI： 10.2472/jsms.51.9Appendix_109

Scopus

researchmap

記述言語：日本語   出版者・発行元：一般社団法人 日本機械学会  

DOI： 10.1299/jsmezairiki.2000.0_401

CiNii Books

researchmap

記述言語：日本語   出版者・発行元：日本材料学会  

CiNii Books

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

Effective application of partial preheating by high frequency induction to enlarge the partial diameter of middle carbon steel was experimentally investigated. The partial preheating was carried out by varying preheating times under the same electric power conditions. As all other conditions other than temperature remained constant during the diameter enlarging experiments, the partial preheating effects were clarified to be estimative using a parameter of the σ/σ_y, where σ_y was dependent on temperature. For preheating times of less than 50 sec, the preheating effect for promoting partial diameter-enlargement did not appear due to blue brittleness influences. For preheating times of less than 110 sec, the preheating temperature was greater than about 856K and was most effective for promoting the diameter enlargement to increase easily the D_f/D_0 to above 2 times without generating damage cracks from fatigue.

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

In this research, packaging structures in which chip parts were bonded to the ceramics substrate of Alumina (Al_2O_3) or nitride aluminum (AlN) with electro-conductive adhesive etc. through a thick film conducting electricity, was studied. For the structures, the bonding remaining strength, considered the residual stress caused in a bonding process based on fracture mechanics, was evaluated, and the influences of both the ceramics substrate and the thick film conductor's thermo-physical property on the strength were examined. Moreover, to examine the decrease behavior of the bonding residual strength by heat cycle loads in-service, thermal cycle tests, the verification tests of a peeling strength, and the simulation analyses of those tests were done, and the peeling fracture strength and the fracture life were predicted. As a result, the mechanism of trouble generated in-service is clarified from the viewpoint of fracture mechanics, the validity of remedies is confirmed, and the present research is useful for the new development of the product.

researchmap

記述言語：日本語  

For the purpose of applying a shape memory alloy ring to combining two separated pipes, the way to exchange the reverse transformation properties of uni-axial stress for those of multi-axial stress was proposed by modeling σ-ε behaviors not only in the process of loading and unloading but also in the process of heating for using to make a FEM analysis. Using the new idea way, the behaviors of deformation recovery and pressure against inserted pipe in the process of ring diameter enlarging and heating for combining two separated pipes were clarified considering the effects of ring diameter enlarging rate and ring thickness. From the viewpoint of saving SMA material cost as well as improving efficiency of ring diameter enlarging works, it was clarified that optimum thickness of ring is about 3mm to 5mm.

researchmap

記述言語：日本語  

In this research, packaging structures in which chip parts were bonded to the ceramics substrate of Alumina (Al_2O_3) or nitride aluminum (AIN) with electro-conductive adhesive etc. through a thick film conducting electricity, was studied. For the structures, the bonding remaining strength, considered the residual stress caused in a bonding process based on fracture mechanics, was evaluated, and the influences of both the ceramics substrate and the thick film conductor's thermo-physical property on the strength were examined. Moreover, to examine the decrease behavior of the bonding residual strength by heat cycle loads in-service, thermal cycle tests, the verification tests of a peeling strength, and the simulation analyses of those tests were done, and the peeling fracture strength and the fracture life were predicted. As a result, the mechanism of trouble generated in-service is clarified from the viewpoint of fracture mechanics, the validity of remedies is confirmed, and the present research is useful for the new development of the product.

researchmap

記述言語：日本語  

It is essential to determine the shape/dimension of shape memory alloy (SMA) before heating that the elastic recovery properties in the process of unloading changes with increasing the maximum strain in the process of loading. Therefore, in this paper, the formula-model was offered for behavior of elastic recovery and was identified by inverse analysis based on series combined model. The average young's modulus was estimated from each modeling formula, respectively.

researchmap

記述言語：日本語  

To execute surgical operations on livers in short time and to reduce the stress on the patients, we propose a soft freezing method for liver surgical procedures. In this surgical procedure, a tumor surrounding the liver is frozen in order to ease the excision and prevent hemorrhage. The effects of cooling velocity and freezing temperation on the excision force by the scalpel on the liver are carried out experimentally as a basic research into partial freezing surgical procedures. In this study, to excise a cancer using free excision curve, the development of the cooling needle and the investigation of the cooling function were carried out using a liver of a pig. The physical properties value was reversely analyzed by using the finite element method based on the heat transfer characteristic data of a mock liver. In addition, the proposed estimation equation can express the relation between arbitrary cooling time and distance and temperature.

researchmap

記述言語：日本語  

We have found a new plastic working method by which an arbitrary size collar can be formed in the middle of a round mild steel bar of φ10 in diameter at room temperature only with rising in temperature below 10℃. This unique plastic working method is carried out by giving the round bar repeatedly an alternate stress of tension and compression by a rotational bending moment under a constant axial-compressive stress below the yield strength. The plastic deforming behavior in the working process are possible to be predicted by the model formula with only a parameter which we have considered in original idea. In the purpose of developing this working method into a various steel bar with various yield strength, 6 kinds of structural steel with φ10 in diameter were collar-formed to clarified the effect of yield strength on the working conditions. The model formula to estimate the deforming behaviors was revised so that the effects of yield strength on diameter enlarging deformation behaviors could be considered into the condition of compressive stress.

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

In this research, we did thermal cycle test, four point bend test, and the simulation analysis by finite element method (FEM) to DBC and AMC semiconductor substrate. We examined influence of thermal-residual stress on the life reliability of the substrates, and did the basic research for establishing a profitable strength evaluation method through the comparison with the two kinds of joint methods. It is clarified that the AMC substrate is more excellent than the DBC substrate from the viewpoint of strength and the longevity reliability of the semiconductor substrate.

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

It was found out that a local collar could be formed on a rod by a combination of compression, bending and axial-rotation temperature rise in collar forming process was below 15℃ in spite of super plastic deformation. This collar forming method is a technology that Baushinger effect can be applied to form collars by giving altemate bending stress of tension and compression to a rod subjected to axial stress slightly below yield strength.

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

To execute surgical operations on livers in a short time and to reduce the stress on the patients, we propose a soft freezing method for liver surgical procedures. In this surgical procedure, a tumor surrounding the liver is frozen in order to ease the ease the excision and prevent hemorrhage. The effects of cooling velocity and freezing temperature on the excision force by the scalpel on the liver are carried out experimentally as a basic research into partial freezing surgical procedures. In this study, to excise a cancer using free excision curve, the development of the cooling needle and the investigation of the cooling function were carried out using a liver of a big. The physical properties value was reversely analyzed by using the finite element method based on the heat transfer characteristic data of a mock liver. In addition, the proposed estimation equation can express the relation between arbitrary cooling time and distance and temperature.

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

Diameter-enlargement works that can form local enlarged diameter in short time at ordinary room temperature and by adding the axial compact force, and adding the rotation and the bend at the midpoint of constant diameter shaft is a new plastic deformation method that has superiority in saving resource, energy saving and mild environment. In order to decrease manufacture cost and expand application of Diameter-Enlargement work, we developed a new working method that can form multiple enlarged shafts by Diameter-Enlargement works. In present investigation we made a survey for the deformation behavior during working process of multiple enlarged shafts based on this method and made an equation modeling for the deformation behavior.

researchmap

記述言語：日本語  

researchmap

記述言語：日本語  

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

researchmap

受賞国：日本国

researchmap

受賞国：日本国

researchmap

受賞国：日本国

researchmap

受賞国：日本国

researchmap

受賞国：日本国

researchmap

受賞国：日本国

researchmap

researchmap