This paper describes the effect of kind and thickness of the metal layer on the actuator characteristic of active laminate was examined experimentally and compared with theoretical value obtained from three-layered beam model. Various types of the laminates made of the metal layer, that is, aluminum, 2024 aluminum alloy, SUS304 stainless steel, zinc and titanium, a unidirectional CFRP (Carbon Fiber Reinforced Plastics) prepreg and a unidirectional KFRP (Kevlar Fiber Reinforced Plastics) prepreg to insulate them were fabricated by hot-pressing at 393K. The main results are as follows: (1) The experimental values of the curvature of active laminate using mono-layers of CFRP and KFRP prepregs corresponded with theoretical value. (2) Actuation of active laminate was examined and it was theoretically found that aluminum can realize high level of actuation, and it was experimentally found that aluminum and 2024 aluminum alloy could realize high level and unidirectional actuation, and SUS304 stainless steel could realize similar actuation, but caused snap-through around 393K.

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This paper describes fabrication and evaluation of an active laminate having a self-repair function. It was made by hot-pressing of an aluminum plate as a high CTE material, unidirectional CFRP prepregs as a low CTE material and an electric resistance heater, a GFRP cloth prepreg as an insulator between them, a thermoplastic in the GFRP layer as an adhesive for self-healing and copper foils as electrodes. The test pieces for peeling tests were delaminated, and they were heated for actuation of the laminate and melting of the embedded thermoplastic. By this experiment, it was shown that the delamination can be repaired if it is connected to the thermoplastic. So the possibility of self-healing of this material system is clarified.

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The purpose of this study is material development for non-contact torque sensor utilizing magnetostriction ring. We applied FeGa polycrystalline magnetostrictive material which has been studied by the author's grope. However, when actually using it for sensor, it becomes necessary to increase the strength more than that of the present FeGa materials. For this purpose, C element was added to FeGaAl alloy, and then magnetic property and mechanical property were investigated. (Fe-13ga-5Al)-1.5C [at.%] sample showed the value of the 50ppm of the maximum magnetostrictions and the value of 667MPa of fracture stress which seemed applicable as a torque sensor material. The torque sensor system was assembled using this alloy ring on the twisted shaft of non-ferromagnetic material and the output magnetic field was measured by ten adjacent Hall-sensor. The output of (Fe-13ga-5Al)-1.5C [at.%] ring showed the linear line mostly and sensitivity was 47.5m Oe/Nm. that is promising data for the proposed torque sensing systemn.

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An electromagnetic property in a Ni-containing diamond-like carbon film was reported. The film was deposited onto polycrystalline silicon using chemical vapor deposition and the co-sputtering of a Nickel target. The temperature dependence on resistivity was measured in the temperature range of 80-400K. Ac resistance was measured by the four-terminal method. The electric conduction mechanism of these films obeys the hopping conduction model. The reluctance was measured under magnetic field of 0 to 50kOe applied to the normal direction of a test piece. The 0.8% magnetoresistance was observed at room temperature.

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A new smart stress memory patch has been developed which measured maximum stress, number of fatigue cycles and stress amplitude simultaneously using Kaiser effect of AE and crack length. In this study, the characteristics of crack propagation in this smart patch was evaluated. Pure copper was used for this sensor because its good corrosion resistance, stable crack growth and detectability of AE near yield point. Fatigue test was performed under the constant stress amplitude to evaluate the crack growth behavior using the relationship between stress intensity factor range and crack growth rate. The obtained fatigue crack propagation behavior was affected by maximum stress and stress ratio. The modified stress intensity factor was proposed to correct the effect of maximum stress and stress ratio. The master curve of crack propagation characteristics which was not affected by maximum stress and stress ratio could be obtained using this modified stress intensity factor.

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Structural health monitoring (SHM) is determination of integrity for building and structure. It proposes the damage diagnostics by statistical detection as a diagnosis method of SHM in authors' research consortiums. However, a decrease in accuracy occurs when the measurement data to which the time simultaneity has not been established in this method is used. Then, it proposes the method of statistically making amends for the time simultaneity in this research.

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The Unsupervised statistical damage diagnostic method can diagnose soundness of structure from data that will be acquired after set up. Presented method detects structural failure from statistical method that judges the equivalence of two data. One of these is called standard data that will be acquired when structure is normal. Another is called measurement data that will be acquired when structure is operated. However, there are many conditions in actual structure. Therefore, it is difficult to determine the only standard data for long-term diagnosis. So, optimal diagnosis needs optimization of the number of standard data groups. This report shows that application of the method to tunnel ventilation jet fan, the method of optimization of number of standard data groups in actual structure.

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This paper presents a system to detect the debonding progress in skin/stringer structures in a wing box of airplanes using ultrasonic waves. This system uses piezoelectric tranducers (PZTs) to input controlled ultrasonic waves to the structures and fiber Bragg grating (FBG) sensors to receive the propagated waves. To evaluate the debonding precisely, two sensors are attached to the top and bottom surfaces of the skin/stringer structure. Comparison of received waves between these two sensors provides an effective method to determine the condition of the structures. The applicability of this proposed system to the debonding detection was demonstrated by experimental studies. To investigate the influence of the debonding, a perfectly bonded specimen and a specimen with debonding were prepared. The results showed that the wave propagation path and received waveform were affected by the debonding. In particular, the maximum amplitude ratio and the arrival time difference were found to be effective parameters to evaluate the debonding progress quantitatively.

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In the present study, a cure monitoring technique was examined for ultraviolet(UV)-curable polymers cured by using an UV LED apparatus. An UV lamp was also used in the experiments. Raman spectra of the polymers were measured at the radiation power of 64.3mJ/cm^2 by the UV LED and at three kinds of radiation power by the UV lamp. The DOC (Degree Of Cure) was evaluated using the measured spectra. From the results of the measurements, it was found that the Raman spectroscopy adopted in the present study could give the DOC of the UV polymers cured with the UV LED apparatus. In addition, it was shown that the DOC was decided by the total radiation energy not by the radiation intensity. It was also found that the total UV doses needed for complete curing by using the two kinds of UV radiation apparatus were different.

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This paper describes the development of the metal core PZT fiber/aluminum composite. As the metal core PZT fiber is fragile and reacts with molten aluminum, general fabrication processes such as diffusion bonding and casting process are hard to apply to embedding process. In this study, it was found that the interphase forming/bonding method could be used to embed the metal core PZT fiber in aluminum matrix. The effect of hot-pressing condition, that is, hot-pressing temperature, pressure and period and clearance between the U-groove and the metal core PZT fiber on the microstructure of the composite, was investigated, and the optimum hot-pressing condition to embed the metal core PZT fiber in the matrix without fracture and reaction was clarified.

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This paper describes development of a shape recovery function in the SiC fiber/Al active composite by using its interphase which has a lower melting point than that of the matrix material. The SiC fiber/Al active composite was heated up to T_r which was higher than the melting point of the interphase, and its R.T. curvature was maximized. Then it was deformed in the fiber direction. After heated up to higher than T_r again. By the experiment, it was found that the maximized curvature of the SiC fiber/Al active composite could be recovered by heating above the melting point of interphase layer even after the specimen was subjected to a severe plastic deformation.

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This paper describes development of high performance, that is, large deformation and high output force type active laminate using elastomer. The conventional and single active laminate was made by hot-pressing of an aluminum plate as a high CTE material, a unidirectional CFRP prepreg as a low CTE/electric resistance heating material and an epoxy adhesive film as an insulating material. The high performance type active laminate was made by sandwiching a sheet of elastomer between two conventional and single active laminates. The development was undertaken mainly by investigating the effect of hardness of the elastomer on their deformation and output force characteristics. It was found that the high performance type active laminate doubled the output force of the single active laminate without losing its actuation capability.

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By applying strain at high temperature to polyurethane-shape memory polymer film, followed by holding the strain under various thermomechanical conditions, the behavior of strain recovery by heating after these processes was investigated. In the experiments, the influence of the strain-holding conditions on shape recovery and secondary-shape forming was investigated. The results obtained are summarized as follows. (1) If strain is held at high temperature for short time, irrecoverable strain starts to appear at the holding time t_h=0.5h and strain is not recovered at all at t_h=8h in the case of holding temperature T_h=T_g+20K. In the case of T_h=T_g+10K, irrecoverable strain appears in proportion to initial strain and the rate of secondary-shape forming S is 42% at t_h=8h.

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The deformation properties of shape memory alloys are different between the strain-controlled condition and the stress-controlled condition. The local strain behavior and the temperature distribution induced due the martensitic transformation were investigated for TiNi shape memory alloy under various strain rates and stress rates. The dependence of deformation behavior on loading rate was investigated.

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Smart Vortex Generator (SVG) concept has been proposed by the present authors. The SVG is autonomously transformed between an upright vortex-generating position during take-off and landing and a stowed drag-reducing position during cruise by utilizing a function of Shape Memory Alloy (SMA) and temperature difference between the ground and the cruise altitude. In the previous papers [eg. Ikeda et al., ICAS 2006, 4.7.5], a blade spring was hooked to the SMA curved plate to lay flat the SVG at the cruise altitude. In this paper we discuss whether aerodynamic force can be used instead of the blade spring with a simple mathematical model of the SVG. Result reveals that this SVG can be also transformed from the upright vortex-generating position to the drag-reducing position and vice versa by the change in ambient temperature and aerodynamic force only.

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When an impact loading is applied to a sandwich panel, facesheet bending is caused by pull down due to localized core buckling and this deformation leads to deteriorations in the bending stiffness. In order to repair the core buckling, we developed shape memory alloy (SMA) honeycomb which can recover its original shape by heating. For the SMA honeycomb sandwich panel, we conducted four-point bending test before impact loading, after impact loading, and after recovery. After the impact loading, strain concentration induced by change in distance between two faces caused a decrease in bending stiffness. After heating, however, the buckled core walls were repaired and the strain concentration disappeared. As a result, the bending stiffness was recovered. Then, we conducted an analysis using beam theory and FEA in order to reveal the cause of deteriorations in mechanical properties. From these results, it was confirmed that the SMA honeycomb sandwich is effective for the suppression of the impact damage progress.

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The present work considers the effect of fabricating process on fatigue behavior of high strength low alloy steel (HSLA), which is used to be structural steel. HSLA steel has been designed to provide specific combinations of formability and weld ability properties for fabricating process. Rectangular bar specimens taken from different stages of fabricating processes were used to perform the four-point bending fatigue test under the stress ratio, R, of 0.1. Effects of forming and cold spinning on fatigue performance were investigated comparing with that of as-rolled plate. The results indicated that the increase in fatigue limit resulted from work hardening due to fabricating process.

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In the present work, fatigue behavior of extruded AZ61 magnesium alloy has been evaluated under three different corrosive environments: (a) high humidity environment i.e. 80% relative humidity, (b) NaCl environment, and (c) CaCl_2 environment. The tests were conducted under axial loading at stress ratio, R, of -1 and at a frequency of 20Hz. The results indicated that the fatigue strengths under NaCl and CaCl_2 environments decrease compared to that of 80% relative humidity environment.

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Though magnesium alloy has a long history more than 100 years, it has been being applied to the limited fields due to several reasons. One of them is that the mechanical properties and fatigue characteristics are inadequate for designing high-performance parts, for example automobile suspension arm under cyclic load. In this paper some basic properties of magnesium alloys which are available in the industrial market are examined by tensile test, fracture toughness test and crack propagation test, compared with normal aluminum alloy in order to seek new applications.

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Because of an excellent specific bending strength and specific bending rigidity, the sandwich panel is used as the floor material of the aircraft now. The floor material damages with a locally concentrated load by a sharp heel of high-heeled shoes. In this study, it is attempted that this situation was modeled by the local compression fatigue test of peripherally clamped honeycomb sandwich panel. Then, the residual displacement and the energy lose were studied. Also, the frature mechanism was discussed from the above results and the observation of core and face sheet during the test.

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The fatigue crack growth life and the crack path of micro fillet-shaped solder joints were evaluated by using functions of the fatigue J-integral ΔJ_f and the creep J- integral ΔJ_c , and by applying the criterion Δσ_<θ, max> on ΔJ_I and ΔJ_II. A new auto-mesh generator, which attaches the fine mesh around a crack tip to the original mesh without a crack, was developed for effectively preparing a new mesh pattern of an extended crack. There were much difference in the predicted crack path by criteria of a strain energy density, maximum tangential stress range and equivalent plastic strain range. However the crack path could be successfully predicted by Δσ_<θ, max>. The calculated crack extension life of the solder joints showed considerable difference, because of the comparable effects in the cyclic and time dependency of crack growth.

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Mullite/SiC whiskers/ SiC particles multi-composite, having excellent crack-healing ability and mechanical properties, was hot-pressed in order to investigate the crack-healing behavior under stress and resultant fatigue strength at the temperature of healing. To actualize ceramic components made of the multi-composite, it is necessary to know threshold stress for crack-healing. A semi-elliptical surface crack of 100μm in surface length was made on each specimen. The pre-cracked specimens were crack-healed under cyclic or constant stress by using three-point bending stress at 1200℃, and the resultant bending strength and cyclic fatigue strength were investigated at 1200℃. The pre-crack on the surface of specimens could be healed even under stress. The threshold stresses for crack-healing, determined by evaluating strengths of crack-healed specimens at healing temperature of 1200℃, were found to be 170MPa for both constant and cyclic stresses, corresponding to 80% of bending strength of the pre-cracked specimens. The static and cyclic fatigue strengths of crack-healed specimens were also investigated at healing temperatures of 1200℃.

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Self-crack-healing driven by oxidation of silicon carbide is the most valuable function to improve poor reliability of ceramics. However, the ceramics composite having crack-healing ability exhibit only small efficient temperature region for crack-healing during service. Therefore, the present authors tried to decrease the temperature that crack-healing reaction becomes active as well as to increase the limit temperature for bending strength by nano-sizing the contained SiC. The present study adapted the following reaction to fabricate alumina composite containing nano-size silicon carbide particles. 3(3Al_2O_32SiO_2)+8Al+6C=13Al_2O_3+6SiC The formed SiC particles have a particle size from 50nm to 150nm and exist in alumina grain and on alumina grain boundary. As a result, the temperature that self-crack-healing become active can decrease 200℃ by SiC nano-sizing. Furthermore, the crack-healed specimen has no large strength decrease up to 1300℃. Therefore, new alumina/silicon carbide nano-composite was found to exhibit the in-situ self-crack-healing efficient temperature region of 300℃.

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Alumina is used in various fields as a machined component. However it has a weakness in low fracture toughness. Thus, countless cracks may be initiated randomly by machining, and the cracks decrease the component's mechanical properties and reliability. To overcome this problem, crack-healing ability could be a very useful technology. In this study, Al_2O_3/SiC particle composite was sintered. This alumina exhibits excellent crack-healing ability. Small specimens for bending were made from the Al_2O_3/SiC. A semicircular groove was machined hardly using diamond ball-drill. The local fracture stress was reduced from approximately 820MPa to 300MPa by machining. The machined specimens were crack-healed under various conditions. The fracture stress of these specimens after crack-healing was evaluated systematically at R.T. It was found that the local fracture stress of the machined specimen recovered almost completely by crack-healing. Therefore, it was concluded that crack-healing could be an effective method for improving the structural integrity of machined alumina while reducing machining costs.

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The machined alumina/ 20 vol.% SiC whiskers composite having a semi-circular groove was conducted to various heat-treatments. The change of the local fracture stress at the bottom of semi-circular groove has been investigated as a function of crack-healing temperature and time. By heating at 1400℃ at 10h, the machined specimen was fractured not from the cracks introduced by the hard machining but from the other region. Thus, it was concluded that the machining cracks were completely healed by the above heat treatment. Moreover, The strength at room temperature and elevated temperature (<1300℃) of the machined sample healed exhibited the same levels as that of polished sample healed. It can be demonstrated that the crack-healing was useful for an increase in the strength of machined ceramics economically.

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The crack-healing behavior of the cracks in Si_3N_4/20 wt% SiC composite, which was introduced during machining a semi-circular groove, was studied. The machined specimens were healed in various temperatures and time in air. The optimized crack-healing conditions were found to be temperature of 1400℃ and time of 10h, because the machined specimen healed under this condition exhibited almost same strength as the smooth specimen healed. Moreover, the machined specimens healed had constant strength of about 700MPa up to 1400℃. These results demonstrated that the crack-healing was very useful to reduce machining cost and to increase reliability on Si_3N_4/SiC composite ceramic.

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We developed some new actuators with high responsiveness and giant bending strain of mover device controlled by electrical resistance. Significantly large displacement, high power and reversibility were observed by change in hydrogen pressure.

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We have reported a novel low-voltage driven dry polymer actuators based on single-walled carbon nanotube gels (bucky gels) of ionic liquids. The actuator has a bimorph structure composed of polymer-supported bucky gel electrodes and a polymer-supported ionic-gel electrolyte. In order to improve the performance of the actuator, we further explored the relations between the structure of the actuator film and its performace. Herein we report details of improved response of our bucky gel actuator.

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In order to develop a smart fin-type submersible actuator made by intelligent Materials, preliminary experimental studies are performed. The flow fields around a oscillating hydrofoil, which were made of either rigid or elastic body, were analyzed by PIV. The shapes of the cross-section of the hydrofoils were either a NACA0020 fin or a flat plate. The influence of both the fin materials and shapes on the flow fields was analytically investigated. The propulsive forces due to the hydrofoils and the rotary input to the hydrofoils were also measured.

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The antisymmetric laminate (Al/KFRP/CFRP) consisted of aluminum, Kevlar reinforced fiber, and carbon fiber reinforced plastics can design its shape through curing at high-temperature. The shape of the laminate can be predicted by the Rayleigh Ritz potential energy minimization principle. By using these characteristics, it is possible to control the shapes by controlling joule-heat generated from electric power, which is controlled through the signal of a temperature sensor buried in the laminate. The Al/CFRP antisymmetric laminate is called the smart material. This study aims to develop a method for rotation control of smart material blades of small wind power generators. Two methods of the rotation control, i.e., decreasing-lift method and inducing-stall method, were experimentally carried out. The experiments showed that the inducing-stall method was more efficient than the decreasing-lift method.

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The purpose of this study is to improve the strength property and magnetic property of a Fe-Ga (Galfenol) system magnetostriction alloy, and to develop excellent magnetostriction alloy. And kinds of samples is the FeGaAl alloy which added aluminum as the 3rd element, and the FeGaAl-C alloy which added aluminum and carbon. In this experiment, the rapid solidification ribbon sample was produced using the Nozzleless Twin Rolling Method. The produced sample investigated about many characteristics, such as a strength property, a magnetic property, and the magnetostriction characteristic, using XRD, a tensile test, and VSM. A maximum magnetostriction of Fe-15.6Ga-4.9Al[at.%] alloy was 210ppm and (Fe-79.8Ga-5.0Al)-1.6C[at.%] alloy was 136ppm. In Tensile test, a maximum tensile strength was 859MPa, Young's modulus was 155.2GPa in the (Fe-79.8Ga-5.0Al)-1.6C[at.%] alloy, and a maximum tensile strength was 638MPa, Young's modulus was 103.0GPa in the Fe-15.6Ga-4.9Al[at%] alloy. This result showed that adaptation of the element addition effect and a rapid solidification process produced the excellent magnetostriction characteristic and a strength property.

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Although the Ti-nickel alloy system with superelasticity is used as a wire for dentistry reform now, nickel which is harmful to a human body is contained. Then, development of the superelasticity with non-nickel system alloy which is biocompatible is hurried. We fabricated the magnetic shape memory alloy Fe-Pd thin foil by rapidly solidification method and investigated the superelasticity effect accompanying stress-induced martensite phase. Three alloys of Fe-29.3at%Pd, Fe-29.6at%Pd and Fe-30.4at%Pd are austenite phase at 313K. Annealed Fe-30.4at%Pd foil exhibits large superelasticity of 3.5% at 313K.

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Giant magnetostrictive Fe-Ga alloys are expected as actuator/sensor materials with high respective velocity and huge stress created by the magnetostriction. In order to develop magnetostrictive material induced by low magnetic field, we investigated magnetostrictive (positive magnetostriction/negative magnetostriction) bimorph-layers, that is, Fe_<8O>Ga_<20> ribbon (146μm)/Ni(14μm) film by magnetron sputtering system. The Fe_<8O>Ga_<2O> ribbon was prepared by rapidly solidification. Magnetostrictive property of the cantilever-type foil was measured using an optical lever method. Displacement of the upper part of the foil with length of 22mm was 530μm under low steady magnetic field of 500Oe (40kAm^<-1>) and exhibits little hysteresis. These magnetostrictive properties also are maintained under low frequency of alternating magnetic field. Moreover, the displacement of the foil at the mechanical resonance frequency exhibits a peak and reaches to 2.0mm at week magnetic field of 50Oe (4kAm^<-1>). The magnetostrictive bimorph-layers are useful for application in micro device as micro-pomp.

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Giant magnetostrictive alloys (GMA) obtained have advantages of high responsiveness, high power and low voltage driving. Influences of magnetostrictive thin film on different substrate sheet, composite mover device with both Fe-Tb/Fe-Sm alloy thin films on each side silicon substrate surface, composite mover device with both Fe-Pd/Fe-Sm alloy thin films on each side copper substrate surface of prepared by D.C. magnetron sputtering process were investigated.

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This paper presents positioning device using micro magnetostrictive actuator using Iron-Gallium alloy (Galfenol). Galfenol is a machinable magnetostrictive material with magnetostriction more than 200ppm, Young's modulus of 70GPa and high permeability. The actuator, square rod of Galfenol with winding coil, is simple, low voltage driving and high efficiency compared with PZT type. In this paper, we describe the configuration of first prototype of the positioner and demonstrate the performance. The movement is based on the smooth impact drive mechanism, where the frictionally supported mass is moved step by step by inertia force with the rapid expansion and slow contract of the magnetostrictive actuator.

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Design and manufacturing of a "multi-functional SAW sensor" which have two or more SAW propagation paths for detecting the environmental parameters and structural health monitoring was studied. By forming the thin functional films having different characteristics of non-linear shape memory and linear superelasticity of TiNiCu alloys on the SAW paths, temperature, stress/strain and accumulated mechanical damage etc. could be evaluated. Wireless sensing showed the same tendency to wired-case. These results indicate the effectiveness of the proposed multi-functional SAW sensing device.

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The residual strain and stress around the fiber of the fiber reinforced composite was measured by an electron Moire method. The residual strains around the fibers are released by pushing the fiber out. The released residual strains are measured from electron moire fringes and then residual stress is calculate from residual strain. To fabricate a model grid, an electron beam lithography which can fabricate the grids with frequencies up to 10,000 lines/mm on the composites surface was used. An electron beam scan was used for the master grid. Measurements of the residual stress around the fibers in SiC/Ti-15-3 and boron/epoxy composites show the validity of the method.

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Discontinuously reinforced titanium composites containing TiB and/or TiC are emerging as promising materials for advanced aerospace applications. It is well-known that the mechanical properties of the composite are strongly affected by local deformation events such as damage initiated at the reinforcement/matrix interfaces, propagation of microcracks or shear bands in the matrix, etc. This study was conducted to investigate the in-situ surface nano-deformation characteristics of a discontinuously reinforced titanium composite using an atomic force microscope (AFM). The specimen used in this study was a TiB and TiC reinforced Ti-6Al-4V composite. Tensile test and in-situ observations were conducted using a loading device equipped with an AFM. Surface morphologies of the composite specimens were acquired before the loading and at various stages of the loading. The nano-deformation behavior of the Ti composite based on nanoscale in-situ AFM observation will be discussed.

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In order to discuss the fracture process of mono-composites fabricated by titanium matrix coated on the SiC fiber (SCS-6) by CVD method, tensile test was performed for the mono-composites and the fracture surfaces and the surface of the mono-composites were examined. Two types of relationship between stress and displacement were observed. The one is linear relationship, and the other is non-linear relationship. For the mono-composites having the non-linear load-displacement relationship the second load-displacement curves after first unloading were the same as that for mono-composite having linear relationship. The load-displacement curves for the dissolved fiber of matrix alloys from the mono-composites had linear relationship between load-displacement. In the surface of two mono-composites having non linear relationship many fine cracks were seen and after loaded mono-composites many cracks been extended to the interface between SiC fiber and matrix alloys and debondings were seen at the interfaces. On the other hands, for other the crack and debonding were not observed.

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Spark Plasma Sintering (SPS) has paid to attention in field of development such as the functionally gradient materials, because of lower sintering temperature and shorter sintering time. In this study, Titanium matrix composites (TMC) reinforced with titanium boride (TiB) whiskers have been fabricated by SPS. It is known that TiB whiskers can be formed in titanium by solid-state reaction of titanium and TiB_2 particles. The reacting TiB whiskers were analyzed with scanning electron microscope (SEM) and X-ray difraction (XRD). TMC was sintered at temperature of 800, 900, and 1000℃, at sintering time of 10, 30, and 50 min and volume fraction from 3 to 15%. Tensile tests of the TMC were carried out at room temperature, 200, 400, 600, and 800℃. We will investigate the fatigue strength, Vickers hardness, Young's modulus, and coefficient of thermal expansion.

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Boron fiber reinforced Al matrix composites were fabricated by a pulsed current hot pressing (PCHP) process at a pressure of 32MPa for 600s. Well bonding between the fiber and matrix was obtained by PCHP at a holding temperature of 773K. Interfacial reaction between the fiber and matrix was negligible. Tensile tests were carried out at room temperature for the composites fabricated by PCHP at 773K. Tensile Yield stress of the composites containing 17.2 vol.% boron fiber attained at 600MPa. This value was about 90% of the tensile strength calculated by the force equilibrium equation of a composite along with the fiber axis direction.

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