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No.	Title	Date of publication	Author(s)	Journal name	Volume/number/page	Publishing type	DOI1	URL1	Publisher	Description
1	Deformation Mechanisms of Metal Diaphragms Due to Repeated Valve Actuation: A Preliminary Study Towards Fatigue Life	2023/11	Deformation Mechanisms of Metal Diaphragms Due o Repeated Valve Actuation A Preliminary Study Towards Fatigue Life	Proceedings of the annual International Conference on Structural Engineering and Materials (ICSEM 2023)		Research paper (international conference proceedings)
2	液中プラズマCVD法による単結晶ダイヤモンド合成に関する基礎研究	2022	岡本孝祐豊田洋通朱霞	日本材料学会四国支部学術講演会講演論文集	19th (Web)
3	木製パレット構造設計に関する基礎研究	2022	越智陽朱霞豊田洋通伊藤大樹	日本材料学会四国支部学術講演会講演論文集	19th (Web)
4	Study on wrinkles during rotary-draw bending forming	2018	Xia Zhu Keiji Ogi Nagatoshi Okabe	Materials Science Forum	943 MSF, 43-47	Research paper (international conference proceedings)	10.4028/www.scientific.net/MSF.943.43			© 2019 Trans Tech Publications, Switzerland. The purpose of this research is to determine the state inside the material using finite-element analysis and to improve the performance of a rotary-draw bending forming by clarifying the mechanism of wrinkle generation. An analytical model of rotational drawing was made by using the general-purpose nonlinear finite-element analysis software MSC Marc, and the analytical results were compared with experimental results to verify the validity of the model. Furthermore, the mechanism of wrinkle generation was investigated. With the progress of processing, wrinkles occur not in the R part but in the original tube-side straight-tube part. The coefficient of friction between the tube material and the R portion of the bending mold promotes the occurrence of wrinkles and the growth of the generated wrinkles. Because wrinkles occur even if the friction coefficient between the tube material and bending mold R part is ignored, the generation condition of wrinkles also depends on parameters other than the friction coefficient.
5	Influence of fillet radius of die end on workability of diameter-enlarged process	2018	Xia Zhu Keiji Ogi Nagatoshi Okabe	Materials Science Forum	943 MSF, 34-42	Research paper (international conference proceedings)	10.4028/www.scientific.net/MSF.943.34			© 2019 Trans Tech Publications, Switzerland. This study focus on the diameter-enlarged ratio, which is an important parameter for evaluating the workability of a partial diameter-enlarged process. Moreover, the study attempts to explain the influence of the fillet radius of the die end on the fatigue characteristic of the test piece after forming and the limit of the diameter-enlarged ratio without fatigue damage in the forming process. Three types of dies with different fillet deformations were used, and tensile tests were carried out after the processing was performed on three types of carbon steel. The fatigue properties of the test specimens after forming and the limit of the diameter-enlarged ratio at which no fatigue damage occurred were investigated. The results obtained are as follows: increasing the fillet radius of the die helped to ease the stress concentration at the root of the diameter-enlarged part, and shaft diameter-enlarged processing could be done without fatigue damage. Using a die having a radius equal to or larger than the appropriate fillet radius helped to increase fatigue strength, without causing fatigue damage, even if the diameter-enlarged ratio increased; notch sensitivity increased with an increase in the diameter-enlarged ratio, but the apparent notch sensitivity coefficient decreased with an increase in fillet radius in all the test pieces. A large limit for the diameter-enlarged ratio without fatigue damage may be obtained by using a die with an appropriate fillet radius.
6	Improved workability of diameter-enlarged process for S35C through quenching and tempering heat treatment	2018	Xia Zhu Keiji Ogi Nagatoshi Okabe	Materials Science Forum	943 MSF, 26-33		10.4028/www.scientific.net/MSF.943.26			© 2019 Trans Tech Publications, Switzerland. The hardness test, Charpy impact test, and axial expansion experiment were performed on a medium carbon steel S35C specimen typically used for shaft materials after first subjecting it to quenching and tempering heat treatment under different heating temperatures/time conditions. The effect of the tempering conditions on the mechanical properties of the specimen and the limit of the diameter-enlarged ratio used for evaluating the workability of the partial diameter-enlarged were investigated. The summary of the results are as follows: after quenching at 880 °C, a fine troostite or sorbite structure was obtained under all heat treatment conditions at heating temperatures of 550 °C to 675 °C, and heating times of 0.5 h to 1.5 h. An improvement was shown in the limit of the diameter-enlarged ratio because the quenching and tempering heat treatment led to an increase in the Charpy impact value/ductility as well as a reduction in the hardness, tensile strength, and yield strength; the partial diameter-enlarged process could be performed on the heat treated material at almost the same deformation speed as a cold-drawn material with a much lower axial pressure; it was possible to estimate the diameter-enlarged deformation behavior using the tempering parameter M. We confirmed that the quenching tempering heat treatment performed in this study facilitates the improvement of the workability of the diameter-enlarged.
7	Epitaxial growth of diamond by in-liquid plasma CVD method	2017	Pria Gautama Hiromichi Toyota Xia Zhu Yukiharu Iwamoto Shinfuku Nomura Shinobu Mukasa	Key Engineering Materials	749 KEM		10.4028/www.scientific.net/KEM.749.211			© 2017 Trans Tech Publications, Switzerland. Currently, novel method to synthesize diamond film on material substrate called as in-liquid microwave plasma CVD (IL-MPCVD) has been achieved. It has been studied and improved in addition expected as new method instead of conventional gas phase microwave plasma CVD (MPCVD). The purpose of this study is to synthesize single crystal diamond using IL-MPCVD in high speed deposition. The experimental conditions, methanol was poured in to the reactor. Each of diamond particles (100) and (111) was embedded on the stainless steel substrates (SUS632J2). It was mounted to the substrate holder of in-liquid plasma equipment and installed on the top cover. The distance between the tip of the electrode and the substrate was kept to 1.5mm. A microwave of 2.45GHz was irradiated into the quartz glass tube reactor from the rectangular cavity resonator with 4 mm diameter tungsten electrode and the plasma was generated at its tip. The microwave was adjusted in appropriate power to maintain a certain substrate temperature. Diamond films were evaluated by Raman spectroscopy, Scanning Electron Microscope (SEM) and Laser Microscope (LM). As a result, the best orientation for epitaxial growth was found to be (100) which have film growth gradually and smooth surface. Whereas (111) face has polycrystalline film with irregularity growth and rough surface. The remaining H and C after CO synthesis satisfying H/C>20 is necessary to synthesized diamond using IL-MPCVD. The deposition rate was about 32m/h when both single crystal and polycrystalline diamond film were synthesized.
8	Synthesis of single-wall carbon nanotubes by in-liquid CVD	2017	Hiromichi Toyota Ken Nagaoka Xia Zhu Yoshinari Kato Shinfuku Nomura Yukiharu Iwamoto Hiroaki Yamamoto Yu Shibano	Key Engineering Materials	749 KEM		10.4028/www.scientific.net/KEM.749.217			© 2017 Trans Tech Publications, Switzerland. High-speed synthesis of the carbon nanotubes in liquid is introduced. The conventional method for synthesizing carbon nanotubes is generally known as gas-phase chemical-vapor deposition (CVD). With that method, carbon nanotubes of high purity can be synthesized, but the synthesis rate is low. Even though the synthesized carbon nanotubes are excellent materials, they cannot be used in large quantities. Accordingly, in this study, single-wall carbon nanotubes (SWCNTs) are synthesized by "in-liquid" CVD. Since the molecular density of a liquid is much higher than that of a gas and the liquid has a cooling effect, performing CVD in a liquid can provide a high-speed growth rate of CNTs on substrate materials. A silicon substrate on which cobalt micro particles are deposited as the catalyst was used. Electrical-resistance heating was used for growing carbon nanotubes in pure ethanol. The synthesized nanotubes were analyzed by scanning electron microscope, transmission electron microscope, and Raman spectroscopy. The results of these analyses indicate that SWCNTs were successfully synthesized over a wide area of the substrate surface. By investigating the synthesized carbon nanotubes under varied experimental conditions (such as pressure and substrate surface roughness), it is shown that surface roughness of the substrate and the bubble behavior are related to the synthesis mechanism of the CNTs.
9	Basic characteristics of in-liquid plasma jet and electrode damage	2017	Xia Zhu Taisuke Satoh Hiromichi Toyota Shinfuku Nomura Yukiharu Iwamoto Pria Gautama	Key Engineering Materials	749 KEM, 76-80	Research paper (international conference proceedings)	10.4028/www.scientific.net/KEM.749.76			© 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.
10	Deposition of a diamond-like-carbon film by ion plating and investigation on its adhesiveness	2017	Xia Zhu Kazuki Kubo Hiromichi Toyota Shinfuku Nomura Yukiharu Iwamoto Pria Gautama	Key Engineering Materials	749 KEM, 70-75		10.4028/www.scientific.net/KEM.749.70			© 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.
11	液中ＣＶＤ法による単層カーボンナノチューブの形成	2017	豊田洋通岡村隆志朱霞岩本幸治野村信福	精密工学会学術講演会講演論文集	2017/ 0, 433-434		10.11522/pscjspe.2017A.0_433		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．
12	Synthesis of diamond by in-liquid plasma CVD	2017	豊田洋通, プリアガウタマ, 岩本幸治, 朱霞, 野村信福	精密工学会学術講演会講演論文集	2017/ 0, 435-436			URL	公益社団法人精密工学会	Diamond was synthesized using the in-liquid microwave plasma chemical vapor deposition (IL-MPCVD) as a novel method for synthesizing diamond on various base materials. Microwaves of 2.45 GHz generated plasma in a solution which was comprised of methanol: ethanol (M:E = 97:3). Evaluation of deposited diamond films was done by a Scanning Electron Microscope (SEM) and Raman spectroscopy. Results shows that the IL-MPCVD method can form diamond films on Cu, Si and Fe substrates. The minimum time of film formation of Cu, Si and Fe are 2.5, 3.5 and 5 minutes, respectively. The material that forms carbide layers such as Si is a better substrate to form diamond film by the IL-MPCVD than other metal substrates such as Cu and Fe. The effect of carbon diffusion influences diamond film nucleation and diamond growth. In order to alleviate the carbon diffusion and improve the quality of the diamond film on the Fe substrate, Si has been sputtered on the Fe substrate as an interlayer. It is found that the diamond film can be formed on a Fe substrate using a Si interlayer and that heat treatment and thickening the interlayer improve its quality.
13	大学発産業界行シーズ(研究成果)探訪(vol.200)革新的な成形加工技術の開発・実用化に向けて	2016/12	朱霞	愛媛ジャーナル	30/ 6, 80-83			URL	愛媛ジャーナル
14	1117 Investigation of basic characteristics of liquid in the plasma jet	2016/02/26	FUJIBAYASHI Ryohei KAWAGUTI Motoshi TOYOTA Hiromiti ZHU Xia	講演論文集	2016/ 54				The Japan Society of Mechanical Engineers
15	イオンプレーティング法によるダイヤモンド状炭素膜の形成法に関する研究	2016	久保一貴河本創豊田洋通朱霞	日本材料学会四国支部学術講演会講演論文集	14th
16	カーボンナノチューブの高速形成法に関する研究	2016	長岡謙芝野優朱霞豊田洋通	日本材料学会四国支部学術講演会講演論文集	14th
17	液中プラズマジェットによる高速膜生成装置の開発	2016	佐藤泰輔朱霞豊田洋通	日本材料学会四国支部学術講演会講演論文集	14th
18	Characterization of single-wall carbon nanotubes grown by in-liquid thermal CVD method	2016	Toyota Hiromichi Zhu Xia Kato Yoshinari Shibano Yu Nagaoka Ken Nomura Shinfuku Iwamoto Yukiharu Mukasa Shinobu	The Proceedings of the Thermal Engineering Conference	2016/ 0, G114		10.1299/jsmeted.2016.G114		The Japan Society of Mechanical Engineers	<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>
19	1117 液中プラズマジェットの基本特性の調査(熱工学III)	2016	藤林亮平, 川口元志, 豊田洋通, 朱霞	中国四国支部総会・講演会　講演論文集	2016/ 0, _1117-1_-_1117-2_			URL	一般社団法人日本機械学会
20	液中熱 CVD による単層カーボンナノチューブの成長特性	2016	豊田洋通, 朱霞, 加藤吉成, 芝野優, 長岡謙, 野村信福, 岩本幸治, 向笠忍	熱工学コンファレンス講演論文集	2016/ 0			URL	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>
21	Synthesis of single-wall carbon nanotubes using in-liquid CVD method	2015/12	Hiromichi Toyota Yoshinari Kato Yu Shibano Xia Zhu Shinfuku Nomura Shinobu Mukasa	Proceedings of the 4th Joint Conference on Renewable Energy and Nanotechnology		Research paper (international conference proceedings)
22	Synthesis of the DLC film using ion plating method	2015/12	Hiromichi Toyota Soh Kawamoto Xia Zhu Shinfuku Nomura Shinobu Mukasa	Proceedings of the 4th Joint Conference on Renewable Energy and Nanotechnology		Research paper (international conference proceedings)
23	Synthesis of diamond film by in-liquid plasma CVD	2015/12	Hiromichi Toyota Taishi Kubo Xia Zhu Shinfuku Nomura Shinobu Mukasa	Proceedings of the 4th Joint Conference on Renewable Energy and Nanotechnology		Research paper (international conference proceedings)
24	Controlling wrinkling and flatness during the processing of the bend section of a pipe by applying vibration to the mandrel	2015	Xia Zhu Narumi Wada Keiji Ogi Hiroshi Kurosu Manabu Takahashi Hiromasa Senba	Key Engineering Materials	656-657, 600-603	Research paper (international conference proceedings)	10.4028/www.scientific.net/KEM.656-657.600			© (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.
25	Basic research on new near-net-shape working method for processing multistage shaft	2014	Xia Zhu Kei Ji Ogi Manabu Takahashi Nagatoshi Okabe Kazuki Mori	Applied Mechanics and Materials	473, 35-38	Research paper (international conference proceedings)	10.4028/www.scientific.net/AMM.473.35			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.
26	Deformation behaviors of partial diameter-enlargement part worked under combination loading of torsion and pressure	2014	Xia Zhu Kei Ji Ogi Manabu Takahashi Kazuki Mori Nagatoshi Okabe	Applied Mechanics and Materials	473, 30-34	Research paper (international conference proceedings)	10.4028/www.scientific.net/AMM.473.30			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.
27	Fatigue damage in diameter-enlargement part formed by cyclic bending and axial compressive Load	2014	Xia Zhu Kenichiroh Hosokawa Keiji Ogi Manabu Takahashi Nagatoshi Okabe	20TH EUROPEAN CONFERENCE ON FRACTURE	3, 1499-1504	Research paper (international conference proceedings)	10.1016/j.mspro.2014.06.242		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.
28	GS39 Investigation of wrinkles during rotary draw bending forming	2012/09/22	OKABE Kyohei IWASAKI Hirofumi OGI Keji ZHU Xia OKABE Nagatoshi	M&M材料力学カンファレンス	2012				The Japan Society of Mechanical Engineers	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.
29	PS07 PLASTIC DEFORMATION BEHAVIOR WITH ULTRASONIC VIBRATION	2012/09/22	KATO Daisuke TAKAHASI Manabu OGI Keiji ZHU Xia SAKATA Hiroki FURUKAWA Takahiro	M&M材料力学カンファレンス	2012				The Japan Society of Mechanical Engineers	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.
30	308 Promotion of Plastic Deformation with Ultrasonic Vibration	2012/02/28	SAKATA Hiroki TAKAHASHI Manabu OGI Keiji ZHU Xia FURUKAWA Takahiro KATO Daisuke	講演論文集	2012/ 50				The Japan Society of Mechanical Engineers
31	309 Study on wrinkles during rotary draw bending forming	2012/02/28	INOUE Yoshitaka IWASAKI Hirohumi OGI Keiji ZHU Xia OKABE Nagatoshi	講演論文集	2012/ 50				The Japan Society of Mechanical Engineers
32	Fatigue strength of shaft with diameter enlarged partially by cyclic bending and axial compressive loading	2012	Xia Zhu Nagatoshi Okabe Keiji Ogi Manabu Takahashi	Applied Mechanics and Materials	217-219, 2346-2350	Research paper (international conference proceedings)	10.4028/www.scientific.net/AMM.217-219.2346			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.
33	Simulation of Deformation Behavior of Shaft’s Cross Section Partially Enlarged and Controlled by Cyclic Bending and Axial Compressive Loading through Metal Mold	2010/07	Xia Zhu Nagatoshi Okabe Manabu Takahashi Keiji Ogi Fumiaki Ikuta Yoshitaka Kuwahara	Proceedings of the 9th World Congress on Computational Mechanics and 4th Asian Pacific Congress on Computational Mechanics	XX/ XX, DVD	Research paper (international conference proceedings)
34	Connecting Two Pieces of Material Parts Using Axial-Diameter-Enlarging Method	2010/05	KUWAHARA Yoshitaka OKABE Nagatoshi ZHU Xia OGI Keiji IKUTA Fumiaki	Journal of the JSTP	51/ 592, 460-464	Research paper (scientific journal)	10.9773/sosei.51.460		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.
35	Axial-Diameter-Enlarging Method for Machine Parts with a Final Outer Shape	2010/05	KUWAHARA Yoshitaka OKABE Nagatoshi IKUTA Fumiaki ZHU Xia OGI Keiji	Journal of the JSTP	51/ 592, 455-459	Research paper (scientific journal)	10.9773/sosei.51.455		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.
36	A Processing Method for Partially Enlarging Diameter of a Hollow Shaft by Combination ofCyclic Torsional Load with Axial Compressive Load	2010/04	桑原義孝岡部永年朱霞黄木景二生田文昭村上宗司	塑性と加工	51/ 591, 331-335 (J-STAGE)-335	Research paper (international conference proceedings)	10.9773/sosei.51.331	URL	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.
37	繰り返しねじり荷重と軸圧縮力との組み合わせ負荷による中空軸材への局部軸径肥大加工法	2010/04	桑原義孝岡部永年朱霞黄木景二生田文昭	日本塑性加工学会塑性と加工	51/ 591, 61-65	Research paper (scientific journal)	10.9773/sosei.51.331
38	Investigation on fatigue strength of a shaft with diameter enlarged partially by combination of a cyclic bending load with an axial compressive load	2010	X. Zhu Y. Kuwahara N. Okabe K. Ogi F. Ikuta	Proceedings of SPIE - The International Society for Optical Engineering	7522/ 00, CD-ROM	Research paper (international conference proceedings)	10.1117/12.851963			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.
39	Investigation on fatigue strength of a shaft with diameter enlarged partially by combination of a cyclic bending load with an axial compressive load	2010	X. Zhu Y. Kuwahara N. Okabe K. Ogi F. Ikuta	Proceedings of SPIE - The International Society for Optical Engineering	7522	Research paper (international conference proceedings)	10.1117/12.851963			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.
40	414 A New Concept "JIKUHIDAI" Processing and Mathematical Model for Enlarging Deformation Behavior	2009	KUWAHARA Yoshitaka OKABE Nagatoshi OGI Keiji ZHU Xia IKUTA Fumiaki	学術講演会講演論文集	58			URL	日本材料学会
41	Fracture strength behavior for ceramics/metal jointing structure due to varying amount of metal brazing alloy	2009	N. Settsu M. Takahashi N. Okabe K. Ogi X. Zhu	12th International Conference on Fracture 2009, ICF-12	8					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.
42	Fracture strength behavior for ceramics/metal jointing structure due to varying amount of metal brazing alloy	2009	N. Settsu M. Takahashi N. Okabe K. Ogi X. Zhu	12th International Conference on Fracture 2009, ICF-12	8, 6069-6078	Research paper (international conference proceedings)				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.
43	A04 Experimental study of fit strength in diameter enlargement processing	2008/10/06	山口功祐黄木景二朱霞岡部永年桑原義孝森一樹	日本機械学会九州支部講演論文集	2008				The Japan Society of Mechanical Engineers
44	Plastic working method for enlarging diameter with a final outer shape	2008/10	Y. Kuwahara X. Zhu N. Okabe F. Ikuta K. Ogi	The Proceesings of the 2008 International Manufacturing Science and Engineering Conference		Research paper (international conference proceedings)
45	315 Study on the Local Diameter Enlargement Processing method with the use of high-frequency induction heating	2008/02/26	池田多賀司黄木景二朱霞岡部永年桑原義孝森一樹	講演論文集	2008/ 46				The Japan Society of Mechanical Engineers
46	310 Optimum processing condition for The Local Diameter Enlargement Processing in steel pipes	2008/02/26	高橋哉有朱霞岡部永年黄木景二桑原義孝森一樹	講演論文集	2008/ 46				The Japan Society of Mechanical Engineers
47	Connecting working of two pieces of parts used the axial diameter enlarging method	2008	Y. Kuwahara N. Okabe X. Zhu F. Ikuta K. Ogi	9th International Conference on Technology of Plasticity, ICTP 2008						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.
48	Connecting working of two pieces of parts used the axial diameter enlarging method	2008	Y. Kuwahara N. Okabe X. Zhu F. Ikuta K. Ogi	9th International Conference on Technology of Plasticity, ICTP 2008	/ , 460-465	Research paper (international conference proceedings)				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.
49	Local Diameter Enlargment Deformation Behaviors of Shaft under Load Conditions of Combining Torsional Stress and Compressive Stress	2007/12	Xia Zhu Kazuki Mori Nagatoshi Okabe Keiji Ogi	Proceedings of APCOM'07-EPMESC XI	MS28-5-4	Research paper (international conference proceedings)
50	319 Basic research of torsion diameter enlarging processing	2007/11/16	Murakami Soushi Zhu Xia Kuwahara Yoshitaka Ogi Keiji Okabe Nagatoshi Mori Kazuki	Materials and processing conference	2007/ 15				The Japan Society of Mechanical Engineers
51	320 Application of Diameter Enlarging Processing to Shaft Fit	2007/11/16	Yoshida Osamu Zhu Xia Kuwahara Yoshitaka Ogi Keiji Okabe Nagatoshi Mori Kazuki	Materials and processing conference	2007/ 15				The Japan Society of Mechanical Engineers
52	半導体基板における接合法と強度・寿命信頼性	2007/06	朱霞堤三佳岡部永年	第6回構造物の安全性･信頼性に関する国内シンポジウム論文集(A論文)	143-148	Research paper (scientific journal)
53	Evaluation and 3D-FEM Analysis for Contact Strength of Ceramic Plate in Contact with a Round Bar	2007/04	Yutaka ABE Manabu TAKAHASHI Xia ZHU Nagatoshi OKABE	Journal of Solid Mechanics and Materials Engineering	1/ 4, 490-497	Research paper (scientific journal)	10.1299/jmmp.1.490	URL	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.
54	Diameter expansion deformation behaviors of midair shaft under various processing conditions	2007	Kengo Fujiki Xia Zhu Kazuki Mori Nagatoshi Okabe	MECHANICAL BEHAVIOR OF MATERIALS X, PTS 1AND 2	345-346, 1093-+	Research paper (international conference proceedings)		URL	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.
55	Development of reformative surgery method using partial freezing for the liver	2006/12	M. Takahashi S. Nomura M. Jindai S. Shibata X. Zhu Y. Watanabe K. Kawachi N. Okabe	JOURNAL OF BIOMECHANICAL ENGINEERING-TRANSACTIONS OF THE ASME	128/ 6, 862-866	Research paper (scientific journal)	10.1115/1.2244577		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.
56	E-14 EVALUATION AND 3D-FEM ANALYSIS FOR CONTACT STRENGTH OF CERAMIC PLATE IN CONTACT WITH A ROUND BAR(Session: Fatique/Contact Strength)	2006/11/08	Abe Yutaka Takahashi Manabu Zhu Xia Okabe Nagatoshi	ASMP : proceedings of Asian Symposium on Materials and Processing	2006				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 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.
57	Contact Strength Analysis of Ceramic Plate Subjected to Contact Load with Ball or Round Bar	2006/11	Yutaka Abe Nagatoshi Okabe Manabu Takahashi Xia Zhu	Proceedings of Asian Symposium on Materials and Processing 2006	/ , -	Research paper (international conference proceedings)
58	Development of New Diameter Expansion Processing Method for Hollow Shaft Under Load Conditions Combined Twist and Compression	2006/11	Xia Zhu Nagatoshi Okabe Kazuki Mori Manabu Takahashi Tadashi Iura	Proceedings of Asian Symposium on Materials and Processing 2006	/	Research paper (international conference proceedings)
59	Processing method for enlarging partial diameter of steel shaft heated locally by high frequency induction	2006/10	Kazuki Mori Risa Suzuki Nagatoshi Okabe Xia Zhu Tadashi Iura	INTERNATIONAL JOURNAL OF MODERN PHYSICS B	20/ 25-27			URL	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.
60	Influence of heat-treatment on workability for enlarging partial diameter of carbon steel shaft	2006/10	Xia Zhu Nagatoshi Okabe Kazuki Mori Tadashi Iura	INTERNATIONAL JOURNAL OF MODERN PHYSICS B	20/ 25-27			URL	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.
61	Processing method for enlarging partial diameter of steel shaft heated locally by high frequency induction	2006/10	Kazuki Mori Risa Suzuki Nagatoshi Okabe Xia Zhu Tadashi Iura	INTERNATIONAL JOURNAL OF MODERN PHYSICS B	20/ 25-27, 4093-4098	Research paper (scientific journal)			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.
62	Influence of heat-treatment on workability for enlarging partial diameter of carbon steel shaft	2006/10	Xia Zhu Nagatoshi Okabe Kazuki Mori Tadashi Iura	INTERNATIONAL JOURNAL OF MODERN PHYSICS B	20/ 25-27, 4087-4092	Research paper (scientific journal)			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.
63	203 Application of Diameter Enlargement Work to Tube-Forming for Light Weight Shaft	2006/02/23	ONISHI Makoto OKABE Nagatoshi ZHU Xia MORI Kazuki	講演論文集	2006/ 44				The Japan Society of Mechanical Engineers
64	Application of the Processing Method for Enlarging Partial Diameter to Shaft for Practical Use	2006/01	OKABE Nagatoshi ZHU Xia MORI Kazuki IURA Tadashi	Journal of the JSTP	47/ 540, 49-53	Research paper (scientific journal)	10.9773/sosei.47.49		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 <i>D</i><sub>0</sub>=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 <i>D</i><sub>0</sub>=25mm-40mm for general industrial machines, the processing experiments were carried out under various processing conditions, such as normalized axial-compressive stress σ<sub>c</sub>/σ<sub>y</sub> and bending angle <i>θ</i>. The results obtained are summarized as follows: the collar-forming process can be smoothly performed by selecting the initial interval <i>L</i><sub>0</sub> between zippers within the range of 32mm-62mm, according to both the size of <i>D</i><sub>0</sub> and the curvature radius <i>ρ</i> of the zipper ends; the cycle parameter <i>N</i><sub>0</sub>, which is used to determine the necessary rotation number <i>N</i> for final collar size in a model equation, can be estimated from both (<i>ρ</i>, <i>D</i><sub>0</sub>) and (<i>θ</i>, σ<sub>c</sub>/σ<sub>y</sub>); the deformation behaviors in the radial direction also depend on (<i>ρ</i>, <i>D</i><sub>0</sub>) as well as (<i>θ</i>, σ<sub>c</sub>/σ<sub>y</sub>) and can be estimated from the function of <i>ρ</i>/<i>D</i><sub>0</sub> depending on bending angle <i>θ</i>; the necessary rotation number <i>N</i> has the tendency to increase with an increase in <i>ω</i> in the case of larger diameter.
65	431 Influence of Diameter-Enlargement on Fillet Radius and Beginning of Grip Width	2006	Fhijiki Kengo Okabe Nagatoshi Zhu Xia Mori Kazuki	学術講演会講演論文集	55			URL	日本材料学会
66	4332 Strength and Life Reliability on Semiconductor Substrate by Difference Bond Methods	2006	Okabe Nagatoshi Zhu Xia Ogi Keiji Settsu Nobuhoru	The proceedings of the JSME annual meeting	2006, 221-222		10.1299/jsmemecjo.2006.6.0_221		The Japan Society of Mechanical Engineers	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.
67	3437 Shape Effect on Seismic Characteristics of Single-stage Bellows of TiNi Shape Memory Alloy	2006	SENBA Hiromasa OKABE Nagatoshi ZHU Xia OKITA Keisuke YAMAUCHI Kiyoshi	The proceedings of the JSME annual meeting	2006, 585-586		10.1299/jsmemecjo.2006.1.0_585		The Japan Society of Mechanical Engineers	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.
68	2908 Expanding application of Diameter-Enlargement work to multiple shaft	2006	Kan Haruhiko OKABE Nagatoshi ZHU Xia MORI Kazuki SUZUKI Risa	The proceedings of the JSME annual meeting	2006, 349-350		10.1299/jsmemecjo.2006.1.0_349		The Japan Society of Mechanical Engineers	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.
69	Fatigue damage of shaft with the collar formed by a new deformation processing method for enlarging partial diameter	2005/12/01	X. Zhu N. Okabe K. Mori M. Tsutsumi T. Iura	11th International Conference on Fracture 2005, ICF11	4			URL		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.
70	Influence of joint structure of ceramic-metal on its residual strength	2005/07	Xia Zhu Nagatoshi Okabe Manabu Takahashi Masako Nakahashi	Zairyo/Journal of the Society of Materials Science, Japan	54/ 7, 741-747	Research paper (scientific journal)	10.2472/jsms.54.741		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 Ieq 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 ΔK Ieq between fracture toughness K IC and K Ieq. 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.
71	Application of Processing Method to Enlargement of Diameter of Hollow Round Bar as Shaft	2005/06	OKABE Nagatoshi ZHU Xia MORI Kazuki IURA Tadashi	塑性と加工 = JOURNAL OF THE JAPAN SOCIETY FOR TECHNOLOGY OF PLASTICITY	46/ 533, 90-94	Research paper (scientific journal)			日本塑性加工学会
72	Influence of Strength Properties on Diameter Increase for Processed Material during the Process of Enlarging a Partial Diameter	2005/04	IURA Tadashi OKABE Nagatoshi ZHU Xia	塑性と加工 = JOURNAL OF THE JAPAN SOCIETY FOR TECHNOLOGY OF PLASTICITY	46/ 531, 55-59	Research paper (scientific journal)			日本塑性加工学会
73	Tensile strength change of silicon nitride/stainless steel joints during neutron irradiation	2005/02	Masako Nakahashi Toshiaki Ito Yasushi Goto Yuji Yasuda Xia Zhu Nagatoshi Okabe	Yosetsu Gakkai Ronbunshu/Quarterly Journal of the Japan Welding Society	23/ 1, 88-94	Research paper (scientific journal)	10.2207/qjjws.23.88		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. 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 1/2 silicon nitride and 25 years for that of 4.4 MPa · m 1/2 silicon nitride. Therefore the life period of the seal parts using silicon nitride that has initial fracture toughness 4.6-5.9 MPa · m 1/2 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.
74	Tensile strength change of silicon nitride/stainless steel joints during neutron irradiation	2005/02	Masako Nakahashi Toshiaki Ito Yasushi Goto Yuji Yasuda Xia Zhu Nagatoshi Okabe	Yosetsu Gakkai Ronbunshu/Quarterly Journal of the Japan Welding Society	23/ 1, 88-94	Research paper (scientific journal)	10.2207/qjjws.23.88		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 1/2 silicon nitride and 25 years for that of 4.4 MPa · m 1/2 silicon nitride. Therefore the life period of the seal parts using silicon nitride that has initial fracture toughness 4.6-5.9 MPa · m 1/2 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.
75	723 On Expanded Application of Diameter Enlarging Processing Method to Rib Forming Work for Plate Material	2005	KURAMOTO Masamichi OKABE Nagatoshi ZHU Xia MORI Kazuki OTANI Masato	学術講演会講演論文集	54			URL	日本材料学会
76	2235 Effect of Selective Heating in Diameter Enlagement Work	2005	Okabe N. Zhu X. Mori K. Tanino M. Suzuki R.	The proceedings of the JSME annual meeting	2005, 633-634		10.1299/jsmemecjo.2005.1.0_633		The Japan Society of Mechanical Engineers	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.
77	Generation of Bending Moment and Twist Torque and Temperature Increase during the Working Process for the Production of a Collar in a Round Bar	2005		Japan Society for Technology of PlasticityJ. JSTP	46/ 531
78	Application of processing method enlarging a partial diameter to shaft parts of practical size	2005	K Mori N Okabe Zhu X T Iura	PRICM 5: THE FIFTH PACIFIC RIM INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS AND PROCESSING, PTS 1-5	475-479, 3065-3069	Research paper (scientific journal)			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.
79	軸肥大加工における中空丸棒材の変形挙動特性(G.S. 変形・疲労特性・破壊力学,O.S.1:先進材料の力学解析と強度・機能性評価)	2004/10/25	岡部永年朱霞羅士剛	講演論文集	2004				一般社団法人日本機械学会
80	セラミックスの球-平板接触疲労によるリングラック発生寿命評価(O.S.1-2 樹脂・金属・セラミックスの疲労と破壊,O.S.1:先進材料の力学解析と強度・機能性評価)	2004/10/25	高橋学岡部永年朱霞國方浩司松井實	講演論文集	2004				一般社団法人日本機械学会
81	Generation of Bending Moment and Twist Torque and Temperature Increase during the Working Process for the Production of a Collar in a Round Bar	2004/05	IURA Tadashi OKABE Nagatoshi ZHU Xia	塑性と加工	45/ 520, 33-37	Research paper (scientific journal)			日本塑性加工学会
82	Strength of ring-crack caused by sphere-plate contact of ceramics	2004/03	TAKAHASHI Manabu OKABE Nagatoshi ZHU Xia MATSUI Minoru	Annual journal of engineering, Ehime University	4, 1-9				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.
83	Mechanical properties of the liver	2004/01/21	TANAKA Daisuke TAKAHASHI Manabu OHGI Keizi OKABE Nagatoshi Zhu XHA NAKANISHI Takahide	バイオエンジニアリング講演会講演論文集	2004/ 16				The Japan Society of Mechanical Engineers
84	Fatigue Properties and Fatigue Damage in a Round Shaft with a Collar Formed by a Novel Processing Method for Enlarging Diameter	2004/01	IURA Tadashi OKABE Nagatoshi ZHU Xia	塑性と加工	45/ 516, 45-49	Research paper (scientific journal)			日本塑性加工学会
85	612 豚肝臓の熱物性値の検討(生体・医療材料-III,生体・医療材料,オーガナイスドセッション12,第53期学術講演会)	2004	横石部慶岡部永年高橋学黄木景二朱霞安藤健次	学術講演会講演論文集	53			URL	日本材料学会
86	529 チップ部品実装構造における接着強度信頼性(電子部品・MEMSの信頼性確保,機械・構造物の信頼性,オーガナイスドセッション7,第53期学術講演会)	2004	河本裕亮岡部永年朱霞	学術講演会講演論文集	53			URL	日本材料学会
87	833 部分肥大加工法による帯材のリブ成形における変形挙動(塑性変形・変形挙動-III,一般セッション,第53期学術講演会)	2004	大谷正人岡部永年朱霞	学術講演会講演論文集	53			URL	日本材料学会
88	Strength of ring-crack caused by sphere-plate contact of ceramics	2004	Manabu Takahashi Nagatoshi Okabe Xia Zhu Minoru Matsui	Zairyo/Journal of the Society of Materials Science, Japan	53/ 10		10.2472/jsms.53.1149		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.
89	Strength of ring-crack caused by sphere-plate contact of ceramics	2004	Manabu Takahashi Nagatoshi Okabe Xia Zhu Minoru Matsui	Zairyo/Journal of the Society of Materials Science, Japan	53/ 10, 1149-1155	Research paper (scientific journal)	10.2472/jsms.53.1149		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.
90	A Synergistic Effect of Thermal Cycle and Bending on the Reliability of Ceramics-Metal Joint body Semiconductor Substrates	2003/11/22	TSUTSUMI Mitsuyoshi OKABE Nagatoshi ZHU Xia	The Computational Mechanics Conference	2003/ 16				The Japan Society of Mechanical Engineers
91	Development of Novel Plastic Working Process for Producing a Collar on a Round shaft	2003/11	IURA Tadashi OKABE Nagatoshi ZHU Xia	塑性と加工	44/ 514, 45-49	Research paper (scientific journal)			日本塑性加工学会
92	Bond Strength and Reliability in Packaging Structures of Chip Parts	2003/09/23	OKABE Nagatoshi ZHU Xia KII Tsuyoshi	Proceedings of the ... annual meeting of JSME/MMD	2003				The Japan Society of Mechanical Engineers	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.
93	THERMAL CYCLIC STRENGTH OF CERAMICS-METAL JOINT BODY SUBSTRATE FOR SEMICONDUCTOR DEVICE	2003/06	M. Tsutsumi N. Okabe X. Zhu	Proceedings of the 9th International Conference on the Mechanical Behaviour of Materials (ICM9)	CD-ROM	Research paper (international conference proceedings)
94	Strength estimation of ceramic-metal joints with various interlayer thickness	2003/05	M Takahashi N Okabe Zhu X K Kagawa	FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES	26/ 5, 391-398	Research paper (scientific journal)	10.1046/j.1460-2695.2003.00581.x		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.
95	Diameter Enlargement Work against Some Kinds of Steel and Plastic Deformation	2003	OKABE Nagatoshi IURA Tadashi Zhu Xia OKAMOTO Mitsuhiro	The proceedings of the JSME annual meeting	2003, 441-442		10.1299/jsmemecjo.2003.1.0_441		The Japan Society of Mechanical Engineers	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.
96	Study on Recovery Mechanism of Elastic Deformation in SMA	2003	Okabe N. Okita K. Zhu Xia Sakuma T. Hosogi M. Yamauchi K.	The proceedings of the JSME annual meeting	2003, 279-280		10.1299/jsmemecjo.2003.1.0_279		The Japan Society of Mechanical Engineers	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.
97	Bond Strength and Reliability in Packaging Structures of Chip Parts	2003	OKABE Nagatoshi ZHU Xia TAKAHASHI Manabu KII Tsuyoshi	The proceedings of the JSME annual meeting	2003, 315-316		10.1299/jsmemecjo.2003.1.0_315		The Japan Society of Mechanical Engineers	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.
98	Fundamental Study with FEM Analysis for Optimizing the Thickness of a SMA Ring to Combine Two Pipes	2003	Okita K. Okabe N. Zhu Xia Hattori S. Sakuma T. Hosogi M.	Proceedings of the 1992 Annual Meeting of JSME/MMD	2003, 697-698		10.1299/jsmezairiki.2003.0_697		The Japan Society of Mechanical Engineers
99	Estimation of cooling characteristic and physical properties of the liver	2003	TAKAHASHI Manabu Zhu XiA OKABE Nagatoshi NOMURA Shinfuku ANDO Kenji YOKOISHI Tsuyoshi	The proceedings of the JSME annual meeting	2003/ 0		10.1299/jsmemecjo.2003.7.0_53		The Japan Society of Mechanical Engineers	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.
100	THE STRENGTH DEGRADATION BEHAVIOR BY HEAT CYCLIC LOADS IN PACKAGING STRUCTURES OF CHIP PARTS	2003	X. Zhu N. Okabe M. Takahashi T. Kii	Proceedings of the 9th International Conference on the Mechanical Behaviour of Materials (ICM9)	CD-ROM	Research paper (international conference proceedings)

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