Nanoindentation has been applied to quantitative characterization of interfaces of bonded materials. Distributions of indentation hardness and Young's modulus on material surface are precisely determined using a load-controlled nanoindentation tester. Two kinds of coatings, a diffusion bonding of aluminum alloy and stainless steel and a spot welding of carbon steels, are used for specimens. It has been found for the diffusion bonding that the intermetallic compound layer of 4μm produced at the interface has higher mechanical properties than the base materials. Two-dimensional mapping of mechanical properties on the cross section of the spot welding has successfully been performed. It has been observed that the properties of the welding area are significantly different from the base material.

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本研究では、試験片にはNi基合金(インコネル738)基材にボンドコートとして減圧プラズマ溶射によりNiCoCrAlY合金(≈150μm)、トップコートとして大気プラズマ溶射によりジルコニア(ZrO_2-8wt%Y_2O_3:≈250μm)を施した遮熱セラミックスコーティングシステムを大気雰囲気中で熱暴露させたものを使用した。熱暴露試験前後の遮熱セラミックスコーティング試験片を用い、ランプ荷重および繰返し荷重の押し込み試験を行った。試験後の遮熱コーティングの界面損傷を観察し、界面劣化や損傷機構について研究した。また、熱暴露試験を行い熱暴露時間がOhから200hに増加するに従ってTGO層の厚さが増加した。

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An ultrasonic technique for monitoring internal temperature of heated materials such as a metal mold is presented. The principle for measuring temperature inside material is based on temperature dependence of the velocity of the ultrasonic wave propagating through the material. A single side of a steel plate of 30mm thickness is heated up to about 75℃ and ultrasonic pulse-echo measurements are then performed for the steel during heating. A change in the propagation time of ultrasonic wave within the heated steel is monitored and used to determine the temperature and its transition at a certain position inside the steel. The internal temperature determined ultrasonically agrees well with that obtained using a commercial thermocouple installed in the steel.

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In order to clarify the influence of non-adhesion area on strength of the honeycomb sandwich panel, three point bending test was carried out by using the specimen in which non-adhesion area artificially made. As a result, the maximum strength and the deformation resistance of the specimen with non-adhesion area were decreased in comparison with the all bonded specimen. And, those values decreased with the increase in the non-adhesion area. Moreover, when two non-adhesion area were made, and the position was changed, it was almost constant. (The total area in non-adhesion area is constant.)

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In order to spread the use of roll core sandwich panel (hereafter, RSP for brevity), it is necessary to clarify the mechanical properties such as the strength and the energy absorption. In this study, a series of static overall compression test was carried out by using specimens changed the core heigh and cell size. From the results obtained in this test, the effects of core height and cell size on strength and energy absorption of RSP were discussed. Moreover, these data of RSP were compared with those of Haneycomb core sandwich panel (hereafter, HSP for brevity). As a result, the similar trends were observed in the data between RSP and HSP. The RSP was superior to the HSP in all data obtained in this study.

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The rotary printing machine requires preventing vibration because the vibration causes printing degradation. The blanket used in the rotary printing machine consists of rubber, sponge and fabric. We investigated dynamic characteristic of the blanket for curbing vibration. Therefore, we conducted dynamic compression impact test by SHPB (split Hopkinson's pressure bar) method and DMA (Dynamic Mechanical analysis). The result showed that elastic modulus of the blanket depended on the strain-rate and frequency.

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Shell structure is one of the most popular structures that are used for the frame of the automobiles and the airplanes. Rib reinforcement method is one of the reinforced methods of the shell structure. In this paper, the best method of rib reinforcement is investigated using structural analysis and stiffness test. The main results are as follow. (1) Rib reinforcement is effective in reinforced method of the shell structure. (2) Rib reinforcement that is attached in the direction of the maximum and minimum principal stress is the most effective to reduce the value of stress and displacement. (3) A lightweight bicycle frame was produced based on these results.

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The telescopic type is the most popular front suspension system of motorcycles on the market. However in telescopic type, steering stability is worsened by braking force. It is possible to improve the steering stability, if the center-hub steering system is applied. In this paper, property and mechanism of center-hub steering system is investigated by designing and manufacturing which use a commercial 50cc motorcycle. The main results are as follows: (1) Rigidity and steering stability of the center-hub steering system are influenced by the shape and the material of the center shaft. (2) It is possible to assemble an engine effectively as a part of the frame.

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A spectrum wave pattern for a plane is a load form based on the data in which many external forces including uncertain elements were collected from many flights. After overloading in a spectrum wave pattern, the delay of the fatigue crack growth may occur. In this study, the model spectrum wave was made by eliminating amplitude of little crack growth from the original spectrum wave pattern, in consideration of the crack opening point after overload. The crack growth behavior obtained from both waves were similar trend and were grouped to three crack growth rate regions such as 1) crack growth acceleration just after the maximum overload in overloads 2) crack growth by overloads after the maximum overload and retardation 3) retardation after the maximum overload. From three crack growth rates, the crack growth curve was able to be predicted.

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The phase transformation of silicon occurs under relatively low pressure of mechanical testing and manufacturing. Especially, nonhydrostatic stress is reported to lower the phase transition pressure by previous experimental studies. In this study, we conducted calculations on the critical stress on the phase transformation of silicon under multiaxial nonhydrostatic stress. Atomistic simulation using simplified model was conducted to obtain ideal critical stress of the phase transformation of silicon. As results, the lowering of the require stress for the phase transformation of silicon was verified and a new stress criterion determining the phase transformation.

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The effects of temperature and strain rate on flow stress of a highly ductile acrylic adhesive were investigated by performing experiments on an adhesively bonded joint at temperatures ranging from 10 to 40℃ at various shear strain rates. The flow stress decreases considerably with decreasing strain rate and with temperature rise. The stress-strain responses under multi-axial stress conditions were also examined by performing combined tension-torsion experiments on the butt-joint. A constitutive model of temperature-dependent elasto-viscoplasticity that describes multi-axial stress-strain behavior of the adhesive is presented.

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Mode II fracture behavior of rubber modified and unmodified epoxy adhesives are studied. Especially to investigate the crack growth behavior in adhesive layers, adhesively bonded end-notched flexure (ENF) specimens were loaded in four point bending. Experimental results were arranged as R-curves. Then, a finite element analysis was also conducted to investigate stress distributions near the crack tip. Based on these results, the effect of rubber modification on the crack initiation and propagation behavior was discussed.

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In this study, fatigue test were conduct for adhesively bonded CFRP/CFRP and Aluminum/Aluminum double cantilever beam (DCB) specimens to investigate the effect of adherend thickness on the crack growth rate. The experimental results indicated that crack propagation rate varied with the adherend thickness. These fatigue crack propagation behavior were discussed from the stress distributions in the adhesive layer and adherend calculated by finite element method.

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Chloroform solutions containing 10-20% polystyrene, of which polymerization degree is 2000, were electrosprayed to produce polystyrene fibers. A stainless tube with inner diameter of 0.66mm is placed vertically 10cm above a circular metal foil with 4cm diameter. The voltage of 10kV was applied between the tube and the metal foil. Polystyrene fibers deposited on the metal foil are observed by an optical microscope. Many beads were observed for electrospun fibers produced from the solution containing 10% polystyrene. When the solution of 20% polystyrene was used, the beads were suppressed and uniform fibers were obtained. The diameter of the fibers were 1.5-1.8μm. A supplementary electrode is used to control the flight of electrosprayed droplet. However, production is not affected by the supplementary electrode.

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Deformation and tensile response of Bamboo fiber mono-filaments treated with alkali solutions for various concentrations are investigated using Instron type tensile testing machine in an atmosphere. The tensile stress-strain response of bamboo fiber mono-filament was observed elastic material response. Additional Alkali treatment with lower concentration is effective to improve the mono-filament strength. These observations were due to increase in the density attended with dissolving lignin and hemicellulose in the NaOH aqueous solution. However, the elastic modulus and tensile strength decreased with higher NaOH concentrations.

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The purpose of this study is to identify and quantify several factors that makes a traditional bamboo bow effective. The bamboo bow is made by sandwiching maple, wax tree and burned bamboo planks between two strips of bamboo. This configuration is similar to hybrid composite but made from 100% natural materials. Since few modern equipment are used during the production of bamboo bow, the perfection of the bow very much depend on the skills and sensibility of the craftsman. Therefore, it is desirable that his implicit knowledge be quantified, especially during the sorting of materials. Here, all the materials were tested for their flexural properties while the flexibility of bamboos was also gauged using vibration tests. These results are enough to define his implicit knowledge.

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Effect of surface treatment for fibers on mechanical properties of bamboo fibers and bamboo fiber reinforced biodegradable plastic composites were investigated. The tensile strength of bamboo fiber increased from 16% to 29% by carrying out a surface treatment on fibers. However, remarkable improvement of strength in composites could not be confirmed because of decrease the bonding capacity between fibers and biodegradable plastic materials by giving surface treatment for fibers.

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In the present study, degradation of poly (lactide) (PLA) and poly (butylene succinate) (PBSU) blends with different mixed fraction were investigated. PLA/PBSU (80/20) was exhibited highest water absorption during hydrolysis tests, whereas biodegradation rate was increased in PLA/PBSU (20/80) on soil burial. Tensile tests were conducted on the blends after 0, 8 and l6weeks hydrolysis tests to evaluate the variation in modulus of elasticity and tensile strength. Modulus of elasticity and tensile strength decreased with increasing PBSU. On the other hand, tensile strength of PBSU was higher than PLA/PBSU (50/50). Modulus of elasticity were less sensitive to hydrolysis, however tensile strength of PBSU content of 50-80w% depend on the hydrolysis tests. It appears that degradation rate increased with increasing PBSU.

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Biocomposites made from bamboo, kenaf and biodegradable resin were fabricated with a press forming. The effect of fiber content on flexural modulus was investigated. The Young's modulus of each fiber was measured to predict the flexural modulus in the composites. The flexural modulus was predicted by Cox model, which incorporated the effect of the fiber compression. The flexural modulus difference between experimental and calculation was large in bamboo. This is because Young's modulus in bamboo fiber was estimated considerably lower than the actual modulus due to partial breakage bamboo structure during fiber tensile test. Moreover, the flexural modulus in the unidirectional fiber composite made a good agreement with the predicted. However, the flexural modulus in the fiber cross ply composites was considerably lower than the predicted. This is because the less fibers movement during hot pressing made the fibers less wetting and resulted in the resin segregation.

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In this research, to develop sliding bearing of biodegradable plastics, it is interesting to improve surface properties and thermal conductivity of the material by ceramic thermal coating and carbon compounding. Frictional coefficient and thermal conductivity of several kinds of Ceramic thermal-coated biodegradable composite plastics are examined. It is found that thermal conductivity of the materials increases with an increase of carbon fiber content. Temperature distributions of test pieces of the materials during friction test were obtained.

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To manufacture the highly functional micro devices by plastic forming, mechanical properties and volume resistivity of polypropylene (pp)/vapor grown carbon nanofiber (VGCF) composite film with orientated VGCF in matrix by drawing and extrusion methods were investigated. All test pieces were prepared from 0°, 45° and 90° as based on drawing direction of composite film. Tensile strength and volume resistivity of drawing direction showed good performances than that from the others. This was due to aligned VGCF by drawing method. On the other hand, the VGCF loading on the tensile property of all composite films contributed to increasing of tensile strength, and the best condition was film reinforced with 20wt% VGCF. Further, the volume resistivity was decreased with increasing of VGCF content, and was less than that of the antistatic film.

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Carbon nanotubes (CNTs) are known to have high electrical properties. By using CNTs as fillers of polymer matrix composites, electrical conductivity of can be improved at small amount of fillers compared with conventional carbon fiber. When CNTs/Polymer composites are fabricated by injection molding, surface resistivity of composite are changed due to fillers orientation or fillers distribution. In this study, influence of injection molding conditions such as mold temperature, injection speed and so on, to the surface resistivity of CNT/PC composites is investigated. As a result, surface resistivity increases when the injection speed and mold temperature increses. From SEM observation of cross section of samples, it is found that the filler orientation angle and the filler density of each specimen are changed at each molding condition. Shear rate distribution near the interface between mold and polymer is largely different at each molding condition from the result of numerical simulation. These results lead that the filler orientation and distribution greatly affects conductivity of CNT/PC composites.

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A small amount of real CFRP processing technology that used Autoclave was unsuitable for production, development in the small and medium-sized enterprise, and an educational research in the higher education organization etc. Then, the simple molding technologies of the clay molding method, the rubber molding method, and PP sheet mold were developed. In addition, the CFRP corner pipe was produced by the Bulge molding using the rubber tube of the bicycle. The CFRP production technology that uses clay and silicon rubber is developed, and those methods reduce 50%-80% cost compared with a usual molding method.

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Applying CFRP to precision machinery components and aerospace materials, CFRPs long-time dimensional accuracy must be secured. Matter for consideration about the dimensional accuracy, moisture absorption, chemical shrinkage, and visco-elastic deformation such as creep are presumable to be the leading factor for the deformation. These deformations are very small, so we need to evaluate quantitative analysis with these factors individually. In this study, we deal with the chemical shrinkage. First, we conducted dynamic DSC measurement to determine the total heat of reaction. Heat of reaction during the cure was measured by isothermal DSC measurement and was quoted to define the extent of cure. A Kinetic model, the Arrhenius model was applied to predict the extent of cure. Our aim is to evaluate the dimensional change concurrent with the cure of epoxy by using laser confocal displacement meter.

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There are prestressed concrete that inserted pre-tension to the piano steel as a means of enhancement of concrete strength. If the prestressed treatment can be applied for carbon fiber reinforced polymer, it can enhance the specific strength, elasticity and fracture stress of the use of aerospace engineering's carbon fiber reinforced in polymer. That is be able to enhance the specific strength, elasticity and fracture stress of carbon fiber reinforced in polymer applied for aerospace engineering. The purpose of the present work is to evaluate influences of prestressing on mechanical property of carbon fiber reinforced in polymer such as elasticity and fracture stress.

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In order to establish the simple method to monitor the carbon fiber reinforced plastics (CFRP) structure, the relation between transverse crack density and sonic velocity was investigated. Tensile and fatigue tests were conducted on the [0/90_2]_s, cross-ply laminates. Both tests were periodically terminated and X-ray observations and wave velocity measurement were conducted. The variation in the wave velocity was measured as a function of normalized Young's modulus and transverse crack density. Normalized Young's modulus is well-predicted with Complete Parabolic Shear-lag analysis, whereas the variation in wave velocity is not affected by transverse crack accumulation.

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This paper describes strain rate effect on mechanical properties of CFRP tube. The investigated relations of CFRP tubes (fiber orientation 0, 30, 60, 75deg) between bending stress and bending strain under lateral impact loading using SHPB (Sprit Hopkinson's Pressures Bar) method. The experimental result pointed that bending stress and bending modulus depended on strain rate. Furthermore, it demonstrated that the higher fiber-oriented specimens produced, the more significant contribution to the strain rate effect.

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In order to clarify the effect of strain rate on the mechanical properties of textile composites, 5-harness satin woven carbon fiber/epoxy composites were tensile tested with a hydraulic testing machine. The actuator speeds were selected as 0.01, 0.1 and 1m/s, which result in the strain rate ranges of 10^<-2>, 10^<-1> and 10^0 s^<-1>, respectively. Experimental results indicated that modulus of elasticity and tensile strength increased at the strain rate more than about 10^0s^<-1>.

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In braided fabric, all fiber bundles are continuously oriented, and the angle of the fiber bundle to the longitudinal direction can be adjusted freely. Therefore, the mechanical properties can be variously designed according to the requirement. The purpose of this study is to clarify the static and dynamic mechanical properties for carbon fiber braided composite tube. Carbon fiber reinforced braided composite tubes, with fiber bundle orientation angle (called "Braiding angle") of 30, 45, 60 degree, were fabricated. 4-point static bending test and 3-point impact bending test were performed for each specimen. After these testing, the cross-section along the braided fiber bundle of the composite was observed to clarify the fracture aspect of the specimens. The effect of the braiding angle on the fracture mechanism of the static bending test and the dynamic one were clarified.

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Textile composites with knitted, woven and braided fabric have been used recently because of the high processability and the high mechanical properties. In particular, braided composite is suitable for continuous structural member with uniform cross-sectional shape like tube, rectangular, I, L structures and so on. In this composite, the excellent performance is expected since the fiber is continuously oriented along the longitudinal direction. In this study, I-shaped cross-sectional braided fabric and composite were fabricated. Using this specimen with glass and carbon fiber, the bending properties of each specimen were investigated. Furthermore, considering the result of bending test and observation, fiber hybrid specimen was designed using both carbon and glass fiber. By optimizing the placement of both fiber materials, the bending properties were improved.

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Viscoelastic property of CFRP is one of most critical parameters which dominate its dimensional stability. In order to investigate the time-temperature dependency of micro-scale deformation, four point bending creep tests were conducted. It is reported that extremely slow cure causes microscopic-scale deformation. So the influence of aged shrinkage upon secular change of dimension was investigated and creep behaviors with two different curing conditions were compared.

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Delayed fracture occurs in unidirectional composites as a result of accumulation of micro-damages, such as fiber breakage or time-dependent interfacial debonding. In this study, the creep rupture lifetime in unidirectional composites is predicted under consideration of the propagation of interfacial debonding and its effect on rupture lifetime and damage accumulation is examined. Predictions were performed for two cases that stress concentration on intact fiber adjacent to broken fiber is not taken into account or taken into account. For former case, the decrease in rupture strain due to time-dependent propagation of interfacial debonding is formulated. For latter case, Monte-Carlo simulation under consideration of interfacial debonding propagating fiber breakage point is performed. As a result, the propagation of stress concentration region is observed and it is thought to be dominant factor for time-dependent damage accumulation in unidirectional composites.

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This paper describes fiber strength degradation of FRP under constant loading in water was investigated using a single fiber composite (SFC) specimen. In experiments, the fiber strength degradation in the SFC specimen was accelerated by water and applied stress. The fiber strength was evaluated by a fragmentation test. We assumed the degradation was caused by microscopic crack propagation and the propagation was accelerated by water and applied stress. Therefore the degradation mechanisms based on the microscopic crack propagation was established to predict the degradation in the SFC specimen. Finally, the experimental results were predicted using the degradation mechanisms.

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Microstructure and mechanical properties of Mg-X-Y (X=Cu, Ni) alloys prepared by casting method have been investigated. Mg_<85>X_6Y_9 (X=Cu, Ni) cast alloys consist of plate like phases with 20〜40μm thick and 200μm width. Long period ordered (LPO) structure with 18R- and 10H-type were observed in both of the Mg-X-Y (X=Cu, Ni) cast alloys. Vickers hardness of the Mg_<85>X_6Y_9 (X=Cu, Ni) alloys were 103HVO.5 and 92HV0.5, respectively. Mechanical property of the Mg_<85>Cu_6Y_9 alloy after hot rolled state was investigated by tensile test. Although the elongation (δ) was limited about 3%, high δ_<0.2> about 300MPa revealed at room temperature.

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Effect of AZ31 magnesium cast alloy for final grain size and mechanical properties by multiaxial alternative forging were investigated. Early work stage, the cast alloy shows duplex structure and locally formed ultra fine grain. The cast alloy was not shows a remarkably improvement of mechanical properties and independence of initial grain size. The purpose of server plastic deformations is homogeneous grain structure, and sever plastic deformation is unnecessary to obtain the fine grain structure in magnesium cast alloy. As a result, mean grain size was obtained about 1μm and elongation was increased 4% to 21% after grain refinement and heat treatment.

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Recycle typed iron aluminide composite have been prepared from waste metals (SUJ2 sludge and Al can pellet) and transition metals by induction melting method. The microstructure of iron aluminide composite consists of Fe_3Al (DO_3-type) and several carbides (TiC, ZrC, V_4C_3, NbC). It was considered that the several carbides reinforced iron aluminide composites were formed by in-situ reaction between transition metals and carbon in the SUJ2 sludge. The aluminide composites have high hardness of 370〜473HV0.5. Wear property of iron aluminide composites were compared with FC200 (cast-iron) at same conditions, and revealed that the iron-aluminide composites have good wear resistance.

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Water of 648K and 22.1MPa or more is called super critical water, which has an excellent organic solvent characteristic. Recently, the application of supercritical water in various fields has been tried. However, metal corrodes in supercritical water environments, especially, reactive containers corrode remarkably from the hydrochloric acid caused in processing of PCB. Therefore, the corrosion of reactive containers and their longevity are serious problems. It is important to make a long-life reactive container. In this study, the corrosive behavior of a nickel based alloy was investigated in supercritical water at 573 to 773K and 20 to 60MPa for 24h. The result was that the corrosion rate was unaffected as the examination temperature increased in all materials. Moreover, the corrosion rate increased as the HCl concentration increased in all materials.

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Effects of alloy element on the latent heat and the temperature of transformation during the heating process are studied experimentally by differential scanning calorimetry. Samples are iron and hyper-eutectoid steel alloys that added chromium or nickel. As chromium is added to the pure iron, the latent heat is hardly changes. Whereas, added to hyper-eutectoid steel, the latent heat is about half of the amount which contains no chromium. And nickel is added to the pure iron, the latent heat increases in proportion to nickel contents. The latent heat of nickel steels has a tendency to decrease.

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Ni rich Ti-Ni Shape Memory Alloys were fabricated by mechanically alloyed powder using pulse-current pressure sintering equipment. The present work studies the effect of solution treatment time on thermal characteristics and tensile properties of the compacts. An increase in solution treatment time achieved a homogeneous TiNi structure, but it caused a decrease in density of the compacts. In the case of the solution time of 21.6ks, the peak of the martensitic transformation disappeared in the DSC curve in spite of detection of B2 phase in the XRD pattern. The aged compacts showed a two-step transformation behavior, but it had no Ti_3Ni_4 precipitate that improves shape memory effect of the alloy.

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Sn-Pb alloy powder was compacted by cold flat rolling for 40〜80% reductions. After rolling, the specimen was cut out in half along the longitudinal direction involving the center line. The shapes of powder particles were measured in deformation area by the rolling. We calculated aspect rate of particles, strain, strain-rate from the measured particle-shapes. And then, distributions of these values in the deformation area are clarified. We can analyze the deformation behavior of powder particles in the rolling process.

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In order to modulate the thermodynamic properties of the (Mg-Al)-H_2 system, the extended homogeneity range of the intermetallic γ-phase Mg_<17>Al_<12> has been studied. Several Mg_xAl_<100-x> samples were prepared by the bulk mechanical alloying (BMA) process. This method was used because of its great advantages for industrial applications (reducing time process, solid preform, large scale production, reducing the surface exposition to the oxidation...). The structures and phase's homogeneity of alloying compounds were analyzed by several experimental measurements and are in mutual agreement with properties of existing phases. The hydrogen absorption properties are presented at 350℃. At 2MPa, samples X=50 and X=58.6 show a maximum hydrogen capacity of 3.5 and 3.7wt% respectively. For these two compounds, the pressure-composition isotherm (PCT) curves show two absorption plateaux. The shape discontinuity corresponds to the transformation of γ-Mg_<17>Al_<12> to the intermediate β-phase (Al_3Mg_2) before the complete decomposition in MgH_2 hydride and pure Al-fcc in a second step. After complete desorption, the initial compounds are recovered, indicates that the reactions are reversible. Theses behaviors are confirmed by X-Rays diffraction (XRD) patterns refined by the Rietveld method.

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To fabricate heatsink devices or ultra-light structural parts, a method of producing micochannels in aluminium with utilizing plastic forming is proposed. In the present study, cylindrical billets containing aluminium powder or tubes with some kinds of resin rods or fibers are extruded at an elevated temperature. It is found that aramid inserts are successful in thinning down without breakage, as a space holder, while the aluminium matrix consolidates during extrusion. The aramid inserts are burned out in the subsequent firing process, and the penetration in the extruded bar is confirmed.

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Several micro and high functional processings by metal powder injection molding (MIM) which uses effectively polymeric materials for enhancing both mold-ability and shape-retention were introduced. Sacrificial plastic mold inserted metal injection molding (SPiMIM) was developed to overcome some problems facing the realization of μ-MIM process. The molds were manufactured by conventional injection molding, rapid plot-typing and LIGA process. A novel production method for the metal components with micro-sized porous structures was also developed by applying powder space holder (PSH) method to MIM process. This method is capable of manufacturing with high dimensional accuracy the micro-porous metal components.

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In this study, electric resistance of a metal film with a spherical shell fabricated by MCT was measured and discussed comparing that from the proposed model. The results show that the electric resistance decreases with the film thickness. It is possible to calculate the film thickness from the proposed model.

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Nano cluster diamond (NCD) dispersed amorphous hydrogenated carbon (a-C:H) film was formed 440C stainless steel using radio frequency (RF) plasma chemical vapor deposition (CVD) method. For 5-hours coating with the applied bias voltage changed, the formed film became 5 times as thick as that coated for 1 hour. The distribution of NCD in the film's depth was surveyed by the glow discharge optical emission spectrometry profiling. Two strain gauge sensors that put on a thin spherical shell equipped with reciprocal sliding tester detect the difference of the strains in sliding directions. The pin-on-disk test using these sensors was performed to examine the lubricity on the surface.

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In thermal sprayed, it is well known that mechanical property of coating is greatly influenced by adhesion process of molten particle. Therefore, it is important to reveal an adhesion process of molten particle. In this paper, tensile test of single splat, which was formed by free fall experiment of molten particle, was conducted to investigate effect of kinetic energy on the adhesion of interface. As obtained results, it was found that adhesion strength increases with kinetic energy as reaching to a critical value, and then decreases with kinetic energy. From a result of optical microscope observation of cross-section of single splat, a correlation was found between the adhesion strength and the adhesion morphology.

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The optical fiber is used as a long-distance transmission line now. Under this situation, the optical fiber must be spliced by the arc fussion. However, the arc fusion results in the decrease of tensile strength of optical fiber. The purpose of this study is to clarify the cause of the decrease of tensile strength. Therefore, tensile tests were carried out by using the arc fusion spliced optical fiber, the striped virgin optical fiber and annealed those fibers. After tests, fracture surfaces of those optical fibers were observed. As a result, the tensile strength of the annealed optical fiber decreased in comparison with that of the striped virgin optical fiber.

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Influences of electron beam (EB) irradiation on fracture stress of ultrafine fiber were studied. Ultrafine fiber had been used for aerospace field and rapid transport field because of light weight, high strength, high heat resistance, high electronic insulation, high corrosion resistance and high wear resistance. However, ultrafine fiber (ceramics fiber) was brittle. Therefore, it was necessary to improve brittleness of alumina fiber. In this study used twisting free tensile tester. EB irradiation was the one of reinforcement methods of ceramics at atmosphere pressure. Thus, EB irradiation enhanced the fracture stress. The fracture stress enhancement can be explained by annihilation of crack origins near fiber surface irradiated.

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Influences of electron beam (EB) irradiation on the surface improvement treatment for transparent glass were studied. Low energy EB irradiation, which was one of short-time treatments of dry process at low temperature, had used for improve process to surface of polymer. EB irradiation enhanced fracture toughness of these glasses. The fracture toughness enhancement can be explained EB irradiation generated dangling bonds of the E' center in these glasses.

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