The integration of micro-parts in alignment with an integrated circuit is a highly important task in assembly process. In any case, a uni-directional control is required since dies, packaging or optical elements, i.e. LED etc., must be positioned to the corresponding sites of the substrate with the correct angular orientation. In this paper, in order to determine an optimum pattern for both the micro-parts and the binding sites, the self-alignment has been comparatively studied using five kinds of modified patterns designed and considered from view point of Overlap ratio, based on a capillary effect.

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The differential bending between two identical cantilevers can be used to reduce the measurement error in various kinds of cantilever type sensors. Geometrically designed interdigitated fingers and a signal detection using optical interference are therefore proposed to further magnify the differential bending for sensing a very small amount of mass variation, due to some kind of molecule adsorption. As a preliminary study, this paper presents findings on nano-mechanical properties of ultra-thin single-crystal silicon (SCS) resonators, with emphasis on their surface effects, resulting from gas adsorption. The measured Q-factors were found to be very sensitive to the surface conditions. This implies that the surface-related mechanism, or adsorption-induced surface stress, should be considered to explain the observed behavior. The results obtained in this study provide an insight into the understanding of effects of gas adsorption on nano-mechanics of resonating elements.

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The reduction of CO_2 in residential and commercial environments is a highly critical task for suppression of global warming. Since 40 % of the total amount of CO_2 exhaust above is the electric power consumption, the R&D of universal-type sensors to monitor electricity usage to improve energy efficiency is of extreme importance. This work however, presents a novel MEMS DC sensor to satisfy the increasing needs for DC power supply with lower transmission loss in future residential and commercial environments. Analytical models are further developed to predict the output voltage and the sensitivity of piezoelectric thin films for guiding the design of a sensor prototype integrated with a permanent magnet. The results show that both the output voltage and the sensitivity of PZT are two times higher than those of AlN.

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With rapidly growing threatens of bird flu and other diseases, there are strong interests in developing battery-free high-sensitivity thermometer for application in wireless sensor network-based animal-health monitoring system. We proposed new 3-D bimorph structure that enables passively digital sensing actuated by event-driven on/off mechanism. Tens and more such 3-D bimorphs are fabricated on a common substrate forming a micro thermometer. The array configuration potentially could have the sensitivity of 0.1℃ and even better. It also enables high fabrication yield and makes the package simplified. This paper would present the fabrication details and the related experimental results.

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Smart textiles using fabric-based sensors to monitor gesture, posture or respiration have been exploited in many applications. Most of fabric-based sensors were fabricated by the techniques including coating piezoelectric materials on a fabric and directly knitting conductive fibers into fabric. In this work, the possibility of generating electric potential by coiled fibers with core-shell structure is studied. The hypnosis is that the electric field or potential could be created between the electrodes of the metal wire and the metal coated on the surface of coiled fiber, when it was squeezed or pressed by supplied forces. In order to investigate the hypnosis, the polyvinylidene fluoride (PVDF) fiber with the core of metal wire was used as the model, and the polarity theory was applied to explain the capability of energy conversions. Moreover, the piezoelectric fabric was designed and the possibility of using this fabric to make textile sensor was investigated.

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In-home healthcare and smart nursing are significantly important in recent years due to the population aging problem and the lacking of human resources. This paper therefore presents a piezoelectric lead zirconate titanate (PZT) thin film actuated and sensed single crystal silicon disk resonator for trace amount of chemicals detection as well as for recognition of gas molecular from human breath. The disk exhibits excellent quality factor and therefore high sensitivity besides its low driving voltage and low power consumption advantageous. It is a promising candidate to be integrated in micro electromechanical systems (MEMS) and wireless sensor network (WSN) for in-home personal healthcare application.

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This paper deals with the problem of dynamic stability of angle-ply laminated cylindrical shells subjected to static and periodic torsion. First, the axially symmetric motion of the shell under loading is determined. Subsequently, certain perturbations are superimposed on this motion, and their behavior in time is investigated. Thesymmetric state of motion of the shell is called stable if the perturbations remain bounded. The solutions for the prebuckling motion and the perturbated motion are obtained by the use of Galerkin's method. Stability regions are examined by utilizing Mathieu's equation. The inevitability of dynamically unstable behavior is proved analytically and the effects of various factors, such us lamination angle fundamental natural frequency, amplitude of vibration and dynamic unstable mode, are clarified.

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Advanced fiber-reinforced laminated plates have been used as structures in various fields because of their high specific strength and stiffness. Postbuckling behaviors of thin laminated plates uniaxial compression have been discussed by many researchers. However, little research has been performed on the secondary buckling phenomenon for thin laminated plates which occurs with further increase of load. In this paper, postbuckling behavior of cross-ply laminated rectangular plates, which are simply supported along four edges, under biaxial compression. The inevitability of postbuckling is proved analytically, and the effects of various factors, such as the biaxial compressive load ratio, aspect ratio, and the outer lamination angle, are clarified.

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This paper presents a multi-scale analysis method for thermo-elastic coupled problems of porous media based on the homogenization method, which accounts for the effects of the size of periodic microstructures or unit cells. The size/scale effect under consideration is supposed to be caused by the amount of microscopic heat transfer. The macroscopic heat conduction phenomena are simulated with variously-sized unit cell models to demonstrate the potential of the proposed method in comparison with the corresponding single-scale direct analyses.

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In this study, the distributions of microscopic stresses at a free edge of a unidirectional carbon fiber-reinforced plastic (unidirectional CFRP) are analyzed three-dimensionally based on a homogenization theory. For this, the mathematical homogenization theory for elastic materials is reconstructed for unidirectional CFRPs with free edges using a traction free boundary condition. This theory is then applied to the analysis of microscopic stress distributions at a free edge of a unidirectional CFRP subjected to in-plane uniaxial tension. It is shown that microscopic shear stress noticeably occurs at the free edge, especially at the interface region between a carbon fiber and epoxy matrix.

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In this study, the elastic-viscoplastic properties of ultra fine plate-fin structures with laminate misalignment are investigated using the time-dependent homogenization theory. For this, it is first shown that, even though plate-fin structures have laminate misalignment, the distribution of perturbed velocity in the structures possesses periodicity. It is further shown that, by employing this periodicity as a boundary condition for boundary value problems, a rectangular unit cell defined for a plate-fin structure with no laminate misalignment can be also used as the analysis domain for the homogenization analysis of plate-fin structures with laminate misalignment. The present method is then applied to the analysis of the elastic-viscoplastic behavior and compressibility of ultra fine plate-fin structures made of Ni-based alloy, under uniaxial tension at high temperature. It is shown that the laminate misalignment can significantly affect both the elastic-viscoplastic behavior and compressibility of the plate-fin structures.

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In this study, a fiber rotation model is introduced into the creep analysis of Carbon Fiber-Reinforced Plastics (CFRP) laminates based on a homogenization theory, to predict the large strain creep behavior of the laminates. For this, a macroscopic elastic-viscoplastic constitutive relation of CFRP laminates is derived based on the time-dependent homogenization theory. Then, the angle of fiber rotation in each lamina induced by in-plane deformation of the laminate is described as a function of macroscopic strain. This fiber rotation angle is introduced into the above-mentioned macroscopic constitutive relation of laminates. Using the present method, the creep behavior of angle-ply carbon fiber/epoxy laminates (T800H/#3631) at an elevated temperature is analyzed. The analysis results for the angle-ply laminates [±45°] are in good agreement with experimental data, showing the validity of the present method and suggesting that the fiber rotation is one of the dominant factors for the creep behavior of angle-ply laminates.

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Off-axis notched strength of a unidirectional CFRP laminate and its fiber orientation and loading mode dependence have been studied. Development of a new engineering method for predicting the off-axis notched strengths in tension and compression is also attempted. Static tension and compression tests were carried out on center hole (CH) specimens with different hole diameters and different fiber orientations. The off-axis tensile and compressive notched strengths are compared to elucidate the loading mode dependence. An anisotropic notch size effect law that takes into account both the effects of fiber orientation and notch size was proposed. Validity of the anisotropic notch size effect law was evaluated by comparing the predicted and observed off-axis notched strengths in tension and compression.

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A procedure for constructing the anisomorphic constant fatigue life (CFL) diagram for composites on the basis of the static strengths in tension and compression and the reference S-N relationship for the critical stress ratio, which was developed by the second author in an earlier study, is further tested on a woven CFRP quasi-isotropic laminate at room and high temperatures. Constant amplitude fatigue tests were first performed at RT, 100 and 150℃ for different stress ratios to elucidate the effects of R-ratio and temperature on S-N relationship. Then, validity of the anisomorphic CFL diagram approach to prediction of the fatigue lives of the composite for cyclic loading at different stress ratios and test temperatures is evaluated by comparing the predicted and experimental results.

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The constant fatigue life (CFL) diagrams for a unidirectional CFRP laminate in its in-plane principal directions are identified. First, constant amplitude fatigue tests were performed at various stress ratios in the longitudinal, transverse and a shear dominated off-axis directions, respectively. On the basis of the fatigue test data, the constant fatigue life diagrams for the unidirectional CFRP laminate subjected to longitudinal, transverse and in-plane shear loading are identified. While the shape of the CFL diagram for longitudinal loading is similar to that observed so far for multidirectional CFRP laminates, a significant difference is observed in the shapes of the CFL diagrams for transverse and in-plane shear loading. Finally, a modified CFL diagram is developed to improve the accuracy of prediction of the transverse and in-plane shear CFL diagrams for the unidirectional composite.

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Stress-life-temperature extrapolation of the off-axis fatigue data on a cross-ply carbon/epoxy laminate is studied. Off-axis static and fatigue tests are performed on coupon specimens with different fiber orientations at different temperatures. The off-axis tensile behavior of the cross-ply laminate significantly depends on fiber orientation and test temperature. The off-axis fatigue failure of the cross-ply laminate takes place predominantly along the fibers in a brittle manner, regardless of the fiber orientation and test temperature. Straight lines can approximately be fitted to the log-log plots of maximum fatigue stress against the number of cycles to failure for all fiber orientations, regardless of the test temperature.

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In order to realize safe and reliable traffic environment, safety technologies that focus on both individual driver and vehicle characteristics is necessary. In this study, driver model which is based on analyzed data with drive recorder is studied. Driver's behavior such as delay, brake pedal stroke, velocity of brake pedal during yellow light is analyzed. In order to evaluate the validity of proposed driver model, numerical simulation with the driver model combined with vehicle model is compared with actual driving data.

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Improvement of analysis precision of thermal fatigue test is required to shorten the development period for power device products. During thermal fatigue test, thermal resistance increases more and more as the crack of solder proceeds. It causes temperature rise of the device and increase of thermal stress and leads to acceleration of the crack propagation. However, conventional crack propagation analysis does not take into account this phenomenon. We developed crack propagation analysis with the capacity of dealing with the change of thermal and electrical boundary condition resulting from the crack propagation. The developed method reproduces the drastic increase of thermal resistance in the latter part of thermal fatigue test and agrees well with the experimental result. We also confirmed that temperature distribution of the device changes as the crack propagates and revealed that thermal and electrical coupled analysis has major effect on the prediction of fatigue life of power device products.

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This experimental study investigated friction and wear of polyetheretherketone (PEEK) containing carbon fibers (CF) sliding against stainless steel in ambient air and dry nitrogen. Dry sliding tests were performed using a pin-on-disk tribometer. In a sliding velocity range 0.2-4.5m/s, average friction coefficient was 0.08 in dry nitrogen, but above 0.25 in ambient air. Microscopic observations showed formations of fine wear particles and stable transfer films especially after sliding in dry nitrogen. The compositional and morphological changes of a frictional interface during the wear process are thought to provide low friction and low wear of PEEK-CF.

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In this study, three kinds of bulk specimens were produced by using 2 liquid-related normal temperature chemical reaction type epoxy adhesive to examine the influence of water upon their mechanical properties. The immersion time in water for each specimen was varied. The Weight of specimens and the Durometer hardness were measured. Fracture stress, Young's modulus and Poisson's ratio were also determined by tensile test Finally, the water influence upon these properties were discussed.

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This paper describes Thermal Stress concentration on tube sheet structures in Fast Breeder Reactor (FBR). Especially, the stress riser exists in the part with the complex structure, and it is important in the heat exchanger to know the thermal stress of the location in the design in detail. This objects are SUS304 perforated plates having different position. We calculated the Stress by FEM Analysis and measured the crack growth by a creep fatigue test under the elevated temperature.

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This study measured the crack growth of perforated plate of SUS304 stainless steel in creep fatigue test as a clue to evaluate the creep fatigue characteristics of a structure member under elevated temperature. Measured was the crack length by using pictures which were photographed with the CCD video camera at every cycle. From the measurement it is found that the total crack growth rate of a creep fatigue increases sharply depending on the period of time or loading rate. And cracks grow up at both sides around the hole, but the growth of each crack may not be symmetric. When the diameter of the test specimen changes, J-integration will be obtained.

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In this paper, heat effect of fire and ignition conditions of electrical cables were shown to evaluate the fire-safety of electrical cables in nuclear fuel processing plant. First, heat effect on cable tray by the combustion by 10L of Ethanol was evaluated numerically by Fire Dynamics Simulator (FDS). As a result, the radiant heat to cable tray at the height of 3.6m was approximately as about 2kW/m^2 by FDS. Moreover, the cone calorimeter test for eco-material (EM) cables which may be used in nuclear fuel processing plant were conducted to evaluate the ignition conditions of electrical cables. As a result, ignition of EM cables was not observed when radiant heat was lower than 15kW/m^2. From the results, the effect of the radiant heat which the combustion by 10L of ethanol gave to cable tray was lower than the radiant heat that ignite EM.

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In this paper, we conducted durability tests of V-packings to propose a new maintenance assessment method. V-packings are fiber-reinforced rubber components to seal the mechanical shaft from fluid. They are used at hydraulic power generator and abraded by rotating shaft. Durability tests were conducted by the device reproducing usage condition of the V-packings in the generator. After the durability test, V-packings were abraded intensely. Nevertheless, from the leak tests results, these V-packings had maintained high seal performance. Then durability test considering environment of river water was conducted. The test powder defined JIS Z 8901 was mixed into circulating water to evaluate the effect of river water on the durability of V-packings and steel shaft. From the test result, effect of the JIS test powder on the abrasion of V- packings and steel shaft was described.

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In this paper, we propose of an orthotropic hyperelastic model for the fiber-reinforced rubber seals used in electric generators. The fiber-reinforced rubber is composed of rubber matrix material that is reinforced by two families of fibers. Its mechanical properties is anisotropic that depend on directions of two fiber families. We modify the Holzapfel model as applying different properties to the warp fiber and weft fiber. Moreover, terms to consider shear deformation were added to the strain energy function. In the function, the energy of the fiber families was represented by exponential functions of invariants of stretch and shear deformation in fiber families. In order to identify material parameter of proposed model, uniaxial tensile test result of the fiber-reinforced rubber were approximated by the nonlinear least squares method.

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This paper, an evaluation of thermal degradation characteristics of EP-rubber used for O-rings in the Gas Insulated Switch Gear (GIS) is described. The gas seal performance of GIS is an important issue for deciding the instrument duration and maintenance period. In order to establish the accurate evaluation methods for thermal degradation of GIS O-rings, biaxial tensile test was conducted to obtain material parameter of EP-rubber. Moreover, some DSC analyses were carried out to validate its applicability to the aging index of EP-rubber.

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The performance of a single stage axial-flow fan with a perforated casing wall was experimentally investigated with a view to improving the stall margin at off-design flow conditions. The annular rows of holes introduced were located midway of the rotor passage and in the vicinity of the outlet from the rotor. A self-circulation system by tubing these two rows of holes led to an expansion of the stall margin without any deterioration of design point efficiency. An optimum opening of the perforation was found in which the stall margin was maximized. These results were compared with those of the free bleeding case.

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Our main aim of this study is to clarify the correlation between the hand motion of front crawl swimmer and the flow field. A former top crawler in Japan and an active tri-athlete on the active list were chosen as subjects. Data on the hand motion and the flow field were obtained using synchronized system of motion analysis and PIV. The results showed that there is a clear correlation between the attack angle of hand and the flow field. It is concluded that we can evaluate quantitatively the correlation between the hand motion of front crawl swimmers and unsteady characteristics of the flow field using our synchronized system.

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Cavitation occurs in the interface between liquid and solid boundary, and causes the damage on the solid wall. Cavitation damage induced by the pressure wave in mercury is a critical issue to realized a MW-class spallation neutron source because the damage degrades the structural integrity of the mercury target vessel. The authors found a luminescence phenomenon due to the cavitation bubble collapsing, through investigating the mechanism of cavitation bubble formation in mercury. In this study, to investigate the relationship of luminescence intensity and cavitation intensity the luminescence phenomena in mercury were experimentally measured using a photomultiplier. The result showed that the luminescence intensity were correlated with the acoustic vibration due to collapse of cavitation bubbles that correspond to the cavitation damage.

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This paper deals with measurement error of an ultrasonic flowmeter located at downstream of an elbow. Velocity fields after the elbow were measured by PIV and the output of the flowmeter was estimated. The measurement error was small when a measurement line where a sound plus propagated was taken in a plane including the elbow's curve, comparing with the case of the measurement line was perpendicular to the elbow's curve plane. The error of the measurement was about 5% at 20D downstream from the elbow (D: the diameter of the pipe). A straightener of the flow was useful to decreasing the error jut after the elbow but not after 20D.

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In Japan Atomic Energy Agency (JAEA), a study on flow induced vibration in the primary cooling system of Japan Sodium cooled Fast Reactor (JSFR) consisting of large diameter pipe and pipe elbow with short curvature radius has been conducted. Flow-induced vibration in the elbow is an important issue in design study of JSFR, because it may affect to structural integrity of the pipe. In this paper, numerical simulations for flow at Re=5x1O^5 through pipe elbows in curvature ratios of 1 and 2 were conducted to validate an in-house LES code named as MUGTHES for the pipe elbow flow and to investigate flow characteristics through the elbows. Numerical results showed good agreement with the experimental results in time average field. Flow characteristics were clarified in relation to the curvature ratio of the elbow.

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In the present paper, the mass transfer phenomenon behind an orifice in a pipe flow is studied by measuring the mass transfer coefficient along the pipe wall using naphthalene sublimation method. An attention is placed on the asymmetrical pipe-wall thinning behind an orifice under the influence of swirling-flow intensity and allowable orifice bias. The present measurement indicates that the mass transfer coefficient becomes asymmetric about the pipe axis by the combined effect of swirling flow and allowable orifice bias. It is found that the enhancement of mass transfer coefficient is observed on the shorter side of the orifice plate and the reduction is found on the opposite side. This phenomenon is found to be consistent with the flow-field observation in the previous study.

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Homogeneous Charge Compression Ignition (HCCI) combustion has attracted considerable interest as a new combustion concept for internal combustion engines. HCCI combustion process has three issues to be resolved: ignition timing control, slower combustion, expanding stable operation region. In an earlier study, the ignition timing can be controlled and the rapidity of combustion can be lessened by using a fuel having two components with different ignition characteristics. In this study, ignition and combustion in an HCCI engine processes were investigated in detail by using spectroscopic measurements, and analyses of chemical kinetic simulations.

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Sodium reacts chemically with water in case of unexpected tube failure of steam generator (SG) in fast breeder reactor (FBR), exoergic reaction produced reaction field with high temperature and high corrosive (sodium-water reaction). Adjacent tubes are exposed to the reaction field and have possibility of overheating rupture by inner pressure with reduction of material strength. It is integral to predict the event with high accuracy that we understand characteristics of heat transfer inside tube in detail. Rapid heating experiment equivalent to sodium-water reaction has been carried out under high pressure, low mass flow rate and high subcooling, Heat flux and temperature on inner wall were estimated correctly by inverse problem solution. As the result of present study, we confirm adequate heat transfer correlations to evaluate overheating tube rupture.

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Analysis for natural convection heat transfer between parallel flat plates was conducted to develop a thermal insulation system. The heat transfer and fluid flow were analyzed to develop an optimum thermal insulating architectural structure. The optimum vent layer size and the optimum cross-sectional shape of thermal insulation system were investigated with the numerical simulation. The vent layer size and the cross-sectional shape were considered along with developing the technique how to control the present thermal system by switching the vent.

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This study focuses on a heat flow characteristic of phase change latent heat storage material (sodium acetate trihydrate, CH3COONa-3H2O, normal melting point of 331 K) in liquid phase state. We discussed the measured results of thermophysical property : density, kinematic viscosity under various temperatures. Further, Observation of liquid natural convection in horizontal sealing container shows that the separation of Benard- cells starts just above the melting point. Therefore, it turned out that the convection in horizontal sealing container has just shifted to the transitional region.

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This study aims at quantifying the objective individual gustatory reactive level. The objective of this study is to analyze EEG pattern when the subjects are given gustatory stimuli (saltiness and sourness) and to discriminate automatically. We extract the personal reference sequential pattern of gustatory stimuli evoked EEG. This study also proposed the automatic LSE(Least Square Error) pattern matching discriminator and investigate the discrimination performance. This discriminator consists of calculating the average of reaction channels which we chose, the moving average (non weighted operation), the phase revision, the removing trend and the normalization. This discriminator shows effective recognition result.

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This study aims at rapid BMI pattern recognition for the eyeball movement, which is considered to be removed a factor from EEG as an artifact. We investigated the repeatability of eyeball movement ERP and the characteristics, which possesses steady, high voltage and 50ms reaction. As an ERP pattern discriminator, this paper proposes 3 methods, which are ISE based, Neighbor Equidistance Linear Mapping and Multilayer Neural Network with BP learning to extract and distinguish characteristic patterns of several directional ocular movements. The reduced model accuracy and characteristics of NN scheme is investigated. As a result, we inspected accuracy improvement of reduced hidden layer unit with weight tuning.

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Diamond like carbon (DLC) film was prepared for on Si, PTFE and PET using a radio frequency (RF) plasma chemical vapor deposition (CVD) device at process pressure of 1-300Pa. In the present study, a nanoindentation and a bending test were performed for evaluating film hardness. For the bending test, the DLC coated on polymer was bended at 90 degrees, and the number of the resulting cracks of the film was counted using a laser-microscope. As a result, the hardness of DLC film decreased with increasing the process pressure.

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Now, the people who substitute a joint, the tooth that a function deteriorated for an artificial joint, an artificial root increase rapidly. Therefore the characteristic found to artificial materials becomes higher very much. The metal materials are used as implant materials widely, and it is often that the fewness to show the toxicity is controlled by metal corrosion resistance. I was aimed for the chemical evaluation of metallic bio materials and I examined metallic bio materials based on the testing method for corrosion resistance of metallic bio materials by anodic polarization measurement (JIS T 0302) standardized by JIS. As a result, the oxidation film of stainless steel and Co-Cr-Mo alloy is appeared the peak of the current density in Eagle MEM. But the oxidation film of Zr-2.5Nb alloy is not

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This research analyzed on the experimental mechanics target about the form of the stem of an artificial hip joint using 2-dimensionl and 3-dimensional photoelastic method. Comparison examination of total hip replacement and the healthy hip joint was carried out. Knowledge was acquired about the stress distribution or the singular point The form of some kinds of stems was examined. As a result, it is remarkable mat the contact state and stress concentration part with a cup of a stem head change with change of form.

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Thermoelastic stress analysis is a full-field, non-contact technique for surface stress mapping of materials and structures. The advantage of the method is its ability to image whole-surface stress (Δ (σ_1+σ_2)) distribution in specimens. An experimental system using the thermoelastic stress analysis method and a synthetic femur was utilized to perform reliable and convenient mechanical biocompatibility evaluation of prosthesis design. A device in which mechanoluminescent materials are applied to a synthetic bone is a "mechanoluminescent synthetic bone." Since the region subjected to load emits high intensity light in the visible region, the device has allowed high-definition and high- speed visualization of the mechanical dynamic environment. It is confirmed that they are very effective and complementally techniques in vitro biomechanics research and to contribute to a variety of biomechanical analyses and thus support the practical implementation of prosthetic devices.

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Guidelines for innovative medical devices such as the artificial heart, the artificial materials, equipments for regenerative medicine, DNA-chips for gene analysis, surgical robots and others are discussed and proposed. Those guidelines are terribly useful for industries that would like to propose review process at PMDA (Pharmaceuticals and Medical Devices Agency) for those innovative medical devices, and suggest evaluation methods for safety and performance of the developed medical devices. Those guidelines are related ISO and/or JIS standards are used, and discussed some standard for those medical devices. Proposed guidelines are opened the public through the METI (Ministry of Economy, Trade and Industry) homepage http://www.meti.go.jp/policy/mono_info_service/service/iryou_fukushi/index.html.

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To develop the manufacturing process of metallic osteosynthesis devices and artificial hip joints, the effects of cold forging conditions on microstructure and hardness of cold forged devices was investigated using grade 2 of commercially pure titanium. The micro cracks were not observed in forged surface, and the microstructure was fine. The hardness increased with increasing the forging load. As the change in surface roughness was small, it was clear that working time for surface finish can be short.

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In an artificial bone that is custom-made medical equipment, there is a trend that artificial bone transplantation has increased compared with autologous bone transplantation because of its safety and less-invasive. However, there are some problems in a metallic artificial bone such as titanium used for load part: (a) The toughness and strength of the metallic artificial bone is much higher than the one of the autologous bone, (b) In the joined part to the human bone part, loosing occurs because uniting with the bone is weak, (c) QOL of patient is low after surgery of mandibular reconstruction. Because, fixation with plate is not shape rebuilding but only functional restoration and there is no custom-made artificial bone for the bone part where a defect has occurred. In order to be solved the above object, the technique for producing custom-made medical equipment consists of biomaterial and based on CT image data corresponding to a shape of the artificial bone has been developed by the metal laser-sintering hybrid milling method which enables a complex shape parts to manufacture with one process and one machine.

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In recent year, studies about creating titanium implants using a layered manufacturing process have been conducted. In this study, Ti-15Zr-4Nb-4Ta alloy was created using an electron beam and Ti-15Zr-4Nb-4Ta powder in the layered manufacturing process. The mechanical properties of the manufacturing material were analyzed.Ti-15Zr-4Nb-4Ta alloy fabricated by electron beam metal molding had the following properties: its microstructure was acicular with an alpha + beta structure; its 0.2% proof stress, tensile strength elongation and elastic modulus are lower than wrought Ti-15Zr-4Nb-4Ta alloy for surgical implant applications.

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Forged goods of the titanium alloy are aimed at and the application development is aimed at to the medical equipment field. The usage is an artificial bone, an artificial joint, and I want to supply exquisite forged goods made in Japan to the market said that the import apparatus accounts for 90 percent now. I announce the development progress.

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The fatigue characteristics that simulated a bone plate having a hole were evaluated. And technique of fatigue duration of life evaluation was studied. A Ti-6Al-4V alloy and SUS316L steel were used for test materials. A specimen configuration is plate of thickness 2mm with both materials. And a penetration hole of a diameter of 2.5mm and 5.5mm, 7.5mm was emptied centrally. A stress concentration coefficient (Kt) is 2.5 and 2.2, 2.1 respectively. The fatigue test performed a uniaxial pulling fatigue test (stress ratio (R) = 0.1, frequency =10Hz, a sine wave). In addition, the examination went in atmosphere environment. A fatigue fracture was observed using SEM. In addition, by a electromagnetic field analysis (FEM), analyzed fracture stress of a hole bottom. And a fatigue fracture mechanism was considered by analyzing load distribution. Fatigue strength of a Ti-6Al-4V alloy is not associated with hole diameter, and fatigue strength is about the same. In other words it was confirmed that there was not influence by size of hole diameter. The fatigue test of SUS316L steel understood that was superior so that hole diameter was large. In addition, fatigue strength of fatigue limit (N_f=10^7 times) is superior so that hole diameter is large. It developed that this was maximum stress (σ max) and a difference of stress distribution.

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In this study, the effect of the shape of a notch and a circular hole on the effect of the evaluation of the plane bending fatigue property in Ti-6Al-4V was examined. Furthermore, the fracture mechanism was clarified based on the evaluation of the depth of crack from the surface. Material used in this study was a Ti-6Al-4V alloy. The used specimens are two types: notch (R=42.5mm, R=2.0mm, R=0.7mm) and circular hole (φ=20mm, φ=6mm). The plane bend fatigue testing is performed under the condition of constant displacement. The testing condition is stress ratio R=-1 and frequency 1OHz. Since fatigue test is conducted under constant displacement condition, the maximum load set at the start of the test decreases when fatigue cracking occurs. The stress distribution around the edge of a circular hole and the maximum stress (σmax) in tensile test is obtained by finite element method (FEM). In the circular hole, fatigue strength becomes lower as the diameter of the hole increase. The stress concentration factor obtained by using FEM for is Kt=6.3φ=20mm and for is Kt=3.0 φ=6mm. Therefore, the fatigue strength of the shape of a notch and a circular hole can be organized with its stress concentration factor. And the effect of the shape of a circular hole can be related to not only the maximum stress but also the stress distribution near it..

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Bone is a typical nanocomposite composed of hydroxyapatite nanocrystals and type-I collagen molecules. That nanostructure realizes biochemical and biomechanical properties of bone. The authors had been reported synthesis of bone-like hydroxyapatite/collagen nanocomposite (HAp/Col) and incorporation of HAp/Col into bone remodeling metabolism. In this paper, the authors report influence of porosity of HAp/Col on regeneration of critical tibia defect of bone. High (H) and low (L) porosity unidirectional porous HAp/Col and core-shell type (C) HAp/Col were prepared from the HAp/Col membrane. Three kinds of HAp/Col were implanted into dog tibia segmental defect of 20 mm in length. After 12 weeks, 90%, 109% and 121% of defect were filled with new bone by H, L and C HAp/Col, respectively. The C-type HAp/Col is expected to be high performance artificial bone to regenerate large bone defect without cells.

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