This paper describes an absolutely new precision cleaning method that jets pure water of a micro size from the special nozzle to have compressed more than 11 MPa. The feature of this method dose clean not only the surface but also the inside of the pin hole on the work piece not to scratch or damage it. And a use volume of a pure water is less than an anther precision cleaning method in spite of the wide cleaning area. The super high presser cleaning method obtains a great effect that is especially two applications for manufacturing process of TFT type color LCD (for Rinsing)and of polishing pad of semiconductor Si wafer (for Dressing).

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In response to the fast growth of the information and telecommunication industries, we developed various kinds of thinner and higher strength steel wires, including the saw wire for silicon wafer slicing (d=0.16〜0.14mm, TS≒4GPa), the brass-clad piano wire for the electric discharge machining (EDM) of the fine-blanking dies (d=0.10〜0.03mm), and the gold-plated piano wire for micro-spring manufacturing (d=0.10〜0.02mm, TS=3.5〜4.5GPa), using the newly developed hypereutectoid steel ( C≧0.90 mass%). And also, we developed the high-strength stainless steel wire (d=0.020〜0.016mm, TS≒3.3GPa) for the larger and finer metal screen for photolithography from the ultra-clean SUS304 steel. High carbon steel wires are electroplated after final heat treatment (patenting) subsequent to the intermediate drawing and redrawn to the final diameter. Stainless steel wires require approximately 99.94% (ε =7.38) of the total reduction of area for the final drawing to secure the sufficiently high strength.

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[in Japanese]

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The mainstream solution in the machining line for aluminum engine components; i.e., cylinder blocks and cylinder heads, has been provided by a transfer line featuring a multi-spindle machining device. In spite of the advantages it can offer, the conventional system is found less appropriate for meeting recent demands. These demands are; minimized investment for adapting the system to new production, and enhanced flexibility to cope with more diversified manufacturing demands. A possible answer would be machinary that simultaneously achieves production efficiency similar to that of the multi-spindle machine and the flexibility of the NC machine. To achieve this goal, the "HVT-6000", an ultra high-speed machining center featuring a tilt-positioning mechanism using direct drive (DD) motors, was developed.

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The machine introduced here is unique among computer numerical control form rolling machines in functions and accuracy. No other machine matches its capabilities. The main die spindle can be tilted by 1/1000 degree gradations even while processing work. Synchronization between the two main dies' spindle rotation angle varies less than 0.1 degrees even under 100KN force. Distance between die spindles can be controlled within micrometers, even under pressure of 100 KN. With these features quality JIS C3 levels of ball screw male thread can be consistently rolled, all the time, every time.

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This paper describes two new types of material test system. One is a Ultra High Cycle Fatigue System. This system makes it possible to confirm a fatigue limit at short time by spending a repeat load on metallic material at the high frequency (lOOOHz), and this system to have made realistic the confirm to the 10^8, 10^9cycle area. Another is a compact High Speed Material Test System, which is designed to measure the stress-strain relation of materials over a wide range of strain-rate from quasi-deformation to dynamic deformation up to 10^3s^<-1>. By changing the attachments for specimens tensile test as well as compression test can be carried out.

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Ductile cast iron has superior mechanical properties and economical merits, so has enlarged its application as material of small- castings, such as automobile parts. However, it has not been applied to large section castings because of its inferior quality due to graphite nodule defect. We have recently succeeded in controlling graphite nodule in large section castings. It has fine graphite nodules all over the thickness, so it has superior mechanical properties in large section castings. Here, we call it as 'Super Ductile'.

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SLS process, which is one of the rapid prototyping (RP), makes it possible that the complex sand cores or sand molds are directly manufactured by 3D CAD data without metallic pattern in a short lead time: In order to fabricare the large and complex castings, the zircon sand suited to this process is developed. In addition, 3D CAD data can be not only made use of SLS process or machining patterns, but cast simulation(CAE).

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In this paper, we describe a die-forming machine for fabricating three-dimensional microcomponents. This is based on the turret punch press, and material processing operations such as rotation of material and other functions are incorporated. The results of practical forming experiments that the developed micropress reliable for fabricating micro components.

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Microformability of superplastic materials and microforming techniques are shown. The materials are fine grained Al-78Zn alloy, transformation superplastic pure iron and new amorphous alloys. The microformability test of each material was done. In the'case of Al-78Zn alloy, microformability depends on the grain size of polycrystalline aggregates. Amorphous alloys reveal perfect Newtonian viscous flow characteristics in the supercooled liquid state and furthermore exhibit an excellent property of microformability on a submicron scale. Microforming techniques are shown as follows; microextrusion with micro-dies made of photochemically machinable glass and made oflaser-micromachined polyimide, submicron imprinting with silicon die fabricated by EB lithography and etching, microforging of microgear of 10 μm in module with microdie fabricated by UV-LIGA process. As a result, bulk metallic glasses(amorphous alloys) are expected to become some of the most useful materials for fabricating MEMS.

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Using an arc ion plating process, crominum nitride films were deposited under a variety of process parameters onto stainless steel substrate. To clarify the effect of process parameters, (are arc current, bias voltage and nitrogen gas pressure) on film quality. The mesurements of the micro particle distribution on film surface were performed. The results obtained were as follows; (1)With the increase in the Nitrogen gas pressure, the micro particle number increases., (2) Under arc current over 100A, the particle number remarkably decreases, (3)The micro particle number slightly increases when the bias voltage decreases. These results seem to result from evaporation and melting behavior of the cathode metal.

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In this study, a novel method of microforging is proposed. The friction stir forming process uses the friction heat generated between a rotating tool and the material being forged. Trials with friction stir forming of various aluminum alloys were carried out on a modified milling machine.

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A new production technique using multistage forging of watch part known as "crown" has been investigated. In the conventional forging process, the scratches on the shearing surface of the mother wire remain on the final products. The deformation behavior of the scratches during multistage forging has been analyzed using FEM and the experiment and a new manufacturing process for improved products is suggested. Carrying out additional forging with a conical punch in the conventional manufacturing process in order to accelerate the metal flow at the center of the sample is useful for obtaining improved final products.

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A description is made to clarify the cutting mechanism of micro drill mechanism. The drilling tests are carried out for stainless steel SUS304, and the drill diameter is 0.1mm,feed rate from 5mm/min to 15mm/min. The relation of micro drill diameter and crystal grain size is the effect on the vicinity to drilling part.

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The mechanical properties of the post-annealed diamond-like carbon (DLC) films were studied using nano-indentation method and ball-on-disk test. DC ion plating deposition technique has been used to deposit DLC on Si(1OO) substrates. The films were also characterized by Raman spectroscopy and thermal desorptioh spectroscopy (TDS). The hardness of the DLC films was found to decrease above 400℃. The results of Raman spectroscopy and TDS showed that at higher annealing temperatures (400℃ <) graphitization occurred for amorphous DLC with hydrogen desorption. It was found that both friction coefficient and wear rate of these films were unaffected by the post-annealing.

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B-C-N films were prepared on single silicon substrates by rf magnetron sputtering using a composite target of diamond and cBN powder. The target was mounted on a rf magnetron cathode,then sputtered by nitrogen and hydrogen gases.The hardness of the B-C-N film increases with increasing hydrogen flow rate,corresponding to a maximum at 10 cm^3/min,followed by a drop above 30cm^3/min. The film was stable for a long time when it was deposited at the substrate temperature of 500℃ .Furthermore that the B-C-N film didn't show the significant weight change under the.heat treatment test at 500℃ in the air,whereas the DLC films were disappeared after the test.These results suggest that the B-C-N film has the potential to be applied to the tribological coatings under relatively high temperature conditions.

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Diamond-like carbon (DLC) films were prepared on SiO_2 substrates by the rf-magnetoron sputtering using a sintered diamond target. It was found that the optical transmittance of the DLC film grown from sintered diamond target with an Ar ion laser beam was about fourfold lager than that grown from graphite target. DLC films were also grown on SUS630 steel substrates by DC-discharge plasma CVD. The nano-indentation hardness test and the ball-on-disk wear test were performed on the DLC coated SUS630 substrates, and the results of these tests revealed that not only the hardness but also the wear resistance of SUS 630 substrates were significantly improved by the DLC coating.

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Effect of phase change from unstable to stable phase on densification process by pressure sintering was studied using mechanically alloyed powder. Powder mixture of Ti and Si having the composition of Ti-37.5mol%Si were milled for 3600ks. The powder showed homogeneous microstructure and amorphous-like XRD profile. Milled powder was vacuum hot pressed at the heating rates of 5, 10 15, 20K/min up to 1273K with applying constant pressure of lOOMPa, then kept for 10.8ks. It was observed that the sudden increase in density at the temperature range between 840K and 905K. This temperature range showed good agreement with that of the phase formation from amorphous to stable phase, Ti_5Si_3. It was observed that the compact under a lower heating rate exhibited higher density and densification rate at the temperature over about 950K. It is concluded that the fine grain superplastic deformation acts an important roll in densification of MA powder having amorphous-like structure.

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Ti-Ni shape memory alloy (SMA) was fabricated by the spark-plasma sintering method using elemental powders. The sintering and heat-treatment conditions were investigated to fabricate superior SMA by this method. Also, the influence of alloy compositions and heat treatment conditions on the thermo-mechanical properties was investigated. The sintered compact improved greatly in mechanical properties and thermo-mechanical properties by the heat treatment. The more the Ni content, the higher the deformation resistance and the recovery stress. The solution-treated compacts were more than 400 MPa in tensile strength and more than 5.5% in elongation at any Ni content, and the solution treated Ti-51.0at%Ni compact was 320 MPa in recovery stress.The thermo-mechanical properties of shape memory training treated compacts and aged compacts are superior to those of solution treated compacts.

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The purpose of this study is to investigate the effect of fabrication conditions on tensile and impact properties of the sintered SUS304L stainless steel compacts made by powder injection molding. The specimen were made of water-atomized and gas-atomized powders which were blended with a polyamide binder system. The compacts were debound in air at various temperatures and sintered in vacuum at 1573 K, 1623 K and 1673 K for 7.2 ks The density and mechanical properties of the sintered compacts were influenced by debinding temperature. The impact value of the sintered compacts increased lineally with increasing density. The powder characteristics influenced significantly on density, microstructure and mechanical properties of the sintered compacts.

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In order to form high toughness amorphous alloy, double mechanical alloying (DMA) was carried out with Ni-Zr amorphous powder by MA and Al mixed powder, here. Obtained amorphous powders were compacted with vacuum hot press (VHP) method, then the excellent conditions of VHP were found. Also mechanical strength of each compact was measured using 3 point bending tests. As a result, it was understood that Al_<60>Ni_<20>Zr_<14> and Al_<60>Ni_<26>Zr_<14> amorphous powders can be compacted and form compacts which has high strength and toughness, where they were compacted for 1.8ks at 773K with 1000MPa loaded. Furthermore, it was known, as well, that both of deflection and rupture strength decreases as amorphous phases begins crystallization.

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The mushy state sintering of the Al powder was investigated to develop the forming process of the Al dust. The compact made from the Al and Si powders was sistered in the mushy state. The density, the microstructure, the vickers hardness and the compressive strength were measured for the obtained material. Furthermore, the mushy state sintering of the Al dust was attempted as well. The nearly dense product could be obtained by the mushy state sintering. The product was consisted of the Al and solidified Si-Al melt phases. From the vickers test and the compressive test, it was found that the sistered material nearly equal commercial Al. By utilizing the process, the nearly dense Al material might be fabricated from the Al dust.

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Mg_2Si is one of the most promising functional magnesium compounds to be synthesized. Mg_2Si is expected to be thermoelectric material system working at relatively high temperature range. Although the conventional milling type mechanical alloying is frequently favored and used among researchers as laboratory-scaled processing, long processing time as well as contamination becomes something an issue of nuisance. The bulk mechanical alloying (BMA) provides us an alternative solid-state processing to synthesize and consolidate Mg_2Si with heat treatment. Within 20-150 cycles of BMA, this starting elemental granular mixture can be fully reacted into Mg_2Si after suitable heat treatment.

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The present paper proposes a new numerical model for predicting the mechanical behavior of unidirectional composites, based on a 3D shear lag model. The present model considers the micro-damage including interfacial yielding. In order to confirm the validity of the present model, the simulated the ultimate tensile strength (UTS) is compared with the experimental result. Then, the damage process is researched by calculating the stress concentration factor (SCF) at the final failure plane.

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The present paper proposes a new numerical model for predicting the mechanical behavior of the CFRP cross-ply laminates(T800H/3631), based on a 3D shear lag model. In order to confirm the validity of the present model, the simulated the ultimate tensile strength (UTS) is compared with the experimental result Then, the effect of the stress concentration on the tip of Transverse Crack is researched by reproducting the inner damages numerically at the crack plane.

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Damage progress in angle-ply [±θ]_s(θ=15, 30, 45, 60, 75°) laminates under tensile Loading were observed by an optical microscope and by a soft X-ray radiography. Matrix cracks and delamination progress were observed before final fracture in θ=15, 30, 45° laminates. On the other hand, no damages were observed until final fracture in θ=60, 75° laminates.

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This paper describes fatigue properties of a quasi-isotropic [0/+45/-45/90]s Alumina. FRP laminates. Matrix crackgrowth behaviors in the laminates under static and fatigue loadings have been studied. Detailed experimental observations were made on the initiation and the growth of individual cracks in 90, -45 and 45 deg plies. Distinctly different crack growth behavior was obtained in each lamina under fatigue loading. At the first of fatigue process, reduction of the stiffness in the laminates due to the 90 deg transverse matrix cracking was obtained. After that, the reduction of that didn't occur, but the transverse cracks in the 90 deg layer were saturated. And then, some delaminations were initiated after the -45 and +45 deg layer's cracks were observed. A higher density of each ply clacks and delaminations would be a characteristic of the fatigue damage in quasi-isotropic Alumina FRP laminates.

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The tensile fatigue tests as well as tensile constant elongation-rate (CER) tests for GFRP/metal conical shaped joint, GFRP/metal adhesive joint, and GFRP/metal bolted joint are carried out under various loading rates and temperatures. The tensile fatigue strength as well as the CER strength for these three GFRP joints depends clearly on time and temperature. The same time-temperature superposition principle holds for CER and fatigue strengths. Therefore, the master curves of fatigue strength for three GFRP joints can be obtained. It is clarified from these master curves that the time-temperature dependent fatigue strength of each GFRP joint shows very characteristic behavior.

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Impact tests of filament-wound carbon fiber composite pipes were carried out using drop-weight impact testing device developed by the authors. Depth of fiber breakage region caused by impact test was evaluated after burst strength test. Burst pressure of composite pipes was also measured in order to investigate the burst strength degradation of pressure vessels due to impact damages. It is clarified that the amount of impact damage of filament-wound composite pipes depends on the impact absorption energy. Furthermore, it is demonstrated that the burst strength of FW-FRP composite pipes after impact was decreased as the increase in cross sectional ratio of damage area.

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This paper describes the characteristics of tensile fatigue in GFRP tube(±45deg) under dynamic cyclic loading at room temperature and 77K. Dynamic cyclic loading tests were conducted at three levels of the maximum stress and the cyclic frequency 10Hz. The relationship between the visco-elastic plastic properties and the internal fatigue damage was investigated at each stress level. The fatigue strength at cryogenic temp, was greatly improved in the range of this study. However, change of the apparent stiffness and hysteresis loss of the specimen were similar behavior.therefor ,similar fatigue damage mechanisms were conjected at each temperature.

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Hardness and biodegradation property of Bionole contained various size of Sugi particle were investigated to reveal that possibility of lowering price and improvement of the properties of biodegradable plastics. In the case of large Sugi particle size, hardness of the composites decreased with increasing of the volume fraction of the Sugi particle, while the hardness were almost constant in the case of the smaller particle size less than 0.6mm. The biodegradation property linearly increased with increasing particle size, then saturated when the particle size became more than 1mm. Moreover, the biodegradation property increased with increasing volume fraction of the Sugi particle.

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Manufacturing composite pipes, lay-up method is generally used to give thickness. However, the method requires several routine processes, and the expense becomes high. Moreover, interfacial and interlamina problem occurs. In order to overcome these problems, the triple layered tubular braiding machine was developed previously. The pipe fabricated by the machine has higher strength than the normal lay-up method. In this study, the energy absorption properties of triple layered tubular braided composite pipes were investigated. Particularly the relationship among reinforcement constructions, fracture morphology and the energy absorption performance were focused. Consequently although triple layered tubular braided composite pipe had good energy absorption properties by showing progressive crushing, energy absorption properties were different among three types of specimens. From these results, it is suggested that location of middle axial fibers dominate not only fracture morphology but also energy absorption performance of triple layered braided composite pipes.

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The aims of this report are to categorize the buckling modes in circular and conical shells under uniaxial compression by using origami models, and also to depict the map of buckling mode for engineering materials.

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The composites, which were made by metal fibers and thermoplastics were used for EMI for electric instrument. In this research, the dependence of resitivity of composites on the mechanical deformation has been studied. The tensile, compressive and bending load were applied the specimen and the change of resitivity was measured.

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This paper deals with sensing of weld pool condition from reverse side and control of penetration in fixed pipe welding. In order to realize full-automatic welding of fixed pipes under high pressure atmosphere, it is important to control the back bead width properly. Accordingly, a method controlling the back bead width from the reverse side is-proposed. As it'is difficult to measure the back bead width directly, it is estimated by analyzing the molten pool shape and the:dimensions. Furthermore, Neural Network is applied so as to estimate the relations among the parameters of the weld pool shape, welding conditions and the penetration of weld. The back bead width is controlled by controlling the welding current estimated from the output of the Neural Network. As the result of welding control experiments, the effectiveness of the proposed system in the penetration control of fixed pipes is verified.

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An intelligent welding robot system with visual sensors is developed in order to realize automatic control of welding conditions. A system to detect the shape and dimension of molten pool using CCD camera and a penetration control system using Neural Network in TIG arc welding are investigated. In order to characterize the shape of molten pool, width, length and area of the molten pool were measured. These shape parameters, welding speed and welding current are input to the neural network, which outputs optimum welding conditions to control the penetration of the molten pool. Consequently, if unexpected changes occur in welding conditions, such as root gap, welding speed and so on, the welding system can optimally control the welding conditions. The constructed system is tested and found to be effective for penetration control in automatic butt welding of thin mild steel plates.

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In automatic butt welding of relatively thin plates, it is important to control welding condition in order to obtain a sound full penetration weld. Recently, it was reported that there is an.intimate relationship between the oscillation of molten pool and penetration. Accordingly, a control system of welding condition in TIG arc welding according to the frequency of molten pool was constructed. But it is difficult to detect the molten pool oscillation, if width of the molten pool is under 6mm. Therefore, pulse-shielding gas oscillating method and pulse back-shielding oscillating method that are more sensitive in detecting oscillation than pulse current oscillating was proposed. In this study, detection system of the peculiar frequency of the molten pool and control system of the welding condition were constructed in TIG arc welding with pulse-shielding gas oscillating method.

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An autonomous mobile robot system with a visual sensor for automatic welding was developed. Algorithm for recognition of welding line and automatic seam-tracking was constructed. The robot has a. movable arm of which position is controlled on cylindrical coordinates and two driving wheels which are equipped at both sides of the vehicle body. The CCD camera is equipped on the movable arm and detects welding line from upper side of base materials. The constructed system can recognize welding line with a visual sensor robustly and track welding line with enough precision and speed as basic performance of welding robot. Consequently, it was confirmed that the system has enough availability and effectiveness to automatic welding.

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It is necessary to understand the behavior of arc that appears in actual welding operation and it makes the welding advanced and intelligent operation. Moreover, the technique is preferred that it is simple and robust. In this research, we examine the technique to presume the welding situation by evaluation of the relation between the welding sounds and the behavior of arc current and voltage. Experiments have been performed under the conditions that the components of shielding gas, their mixture ratio and the polarity of electrode were changed respectively. Some findings were obtained by comparing the sound and image information obtained by each situation of welding.

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