To enhance the mechanical properties of Mg alloys, 0-30vol% Al_2O_3/Mg powders were formed by ball milling powder mixtures of pure Mg and Al_2O_3 particles, and then Spark plasma sintering (SPS) compacts (Al_2O_3/Mg discs) were made by the Al_2O_3/Mg powders The effect of the cooling conditions in the SPS process on the mechanical properties of the Al_2O_3/Mg discs was investigated From the results of SEM, XRD and TEM-EDS, the microstructures of the Al_2O_3/Mg discs were identified to consist of a- Mg solid solution, Al_2O_3 particles, refined MgO particles and refined needle-like Mg_<17>Al_<12> ( more than 20vol% Al_2O_3 content) The mechanical properties of the discs were able to control by the regulation of the cooling conditions (cooling rate (v_c) and applied pressure in the cooling (p_c)) in SPS process, and as a result, the SPS discs possessing the mechanical properties beyond HP compacts were obtained under the cooling conditions of "vc= 0.83K/s and pc= 20MPa" Main factor that the cooling conditions in SPS process effect on the mechanical properties of the Al_2O_3/Mg discs are considered to be the compresive residual stress generated in the α - Mg solid solution by the thermal stress associated with deference of the coefficients of thermal expansion between the α - Mg and ceramics particles (Al_2O_3 and MgO) in the discs

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Transparent alumina compacts were fabricated by using spark plasma sintering method A commercial alumina powders with two different grain sizes were used as raw powder The average grain size of TM-DAR and AA02 powders were lOOnm and 230nm,respectively From results of in-line transmittance measurements, TM-DAR compacts sintered at 1423K and 1473K showed more than 60% of the in-line transmittance In contrast, AA02 compacts sintered at 1423K showed about 47% of the in-line transmittance In TEM observation of TM-DAR compacts sintered at 1423K and 1523K, dense microstructures without pores were observed On the other hand, it was found that AA02 compacts sintered at 1523K contained pores in the grain and line defects, while abnormal grain growth was locally observation in AA02 compacts sintered at 1423K These results indicated that the transparent alumina compacts was strongly affected by the particle size of raw powder, and the compact with dense microstructure showed high transmittance

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Capacitor electrode materials were produced by Spark Plasma Sintering(SPS) with mixed carbon black and activated carbon powder Mixed powder was treated by Mechanical Milling(MM) with alumina balls varying treatment time in the range of from 0 to 12hr The characteristics of obtained samples were evaluated by Scanning electron microscope(SEM),X-ray diffraction(XRD) and four-probe method Following describes the results for samples sintered at a mixing ratio of CB101 activated carbon=1:1 SEM observation revealed that the MM treatment led uniform adhesion of CB101 particles on surface of the activated carbon particles From results of XRD measurements it was found that sintering process and variation of MM treatment time contributed little to the crystal structures of the samples Electrical conductivity of the sintered samples was higher than that of conventional electrode materials, and the conductivity m creased with MM treatment time

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FeSi_2 thermoelectric material possesses superior characteristics such as high oxidation resistance, high corrosion resistance. The thermoelectric conversion module was manufactured using a FeSi_2 thermoelectric conversion element by spark plasma sintering In order to decrease electrical resistance between cupper plate electrodes and elements, two sheets of Ag foil were inserted at either and of FeSi_2 powder when sintering was carried out The module with 1 pair of p-n elements showed open voltage of 92 OmV, electric resistance of 0.9Ω, and maximum output of 2.4mW at temperature difference of 280K While, the module with 8 pairs of elements had open voltage of 927 lmV, electric resistance of 3.5 Q, and maximum output of 62.3mW at temperature difference of 380K It was found that insert of Ag foil sheets decreased the electric resistance of the modules

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Thickness of Ti-6A1-4V Ti alloy was reduced by electrochemical etching, and thickness dependency of its superplasticity was investigated by tensile test By means of electrochemical etching thickness of Ti alloy was reduced while keeping the same inner microstructure For the etching constant current, 1.4 A was applied on electrodes of Ti alloy inside electrolyte, which consists of 300 ml of ethanol, 18 g of AiC1_3, and 75 g of ZnCl_2 And linear reduction of thickness depending on time was confirmed as 3.32 |um/min Using the specimens with different thicknesses superplastic tensile tests were performed at 850 ℃ For quantitative evaluation of superplasticity strain rate sensitivity (m values) were measured changing strain rates during tensile tests The thickness dependency of superplasticity was observed, and thinner specimen showed less superplasticity This phenomenon in micro scale may be caused by relatively larger grain size compared to thickness hindering grain boundary slip, or the effect of relatively dominant oxide film The different trend of superplasticity in micro scale was revealed in this study, thus thickness dependency should be considered when superplastic deformation is applied for micro forming

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Abstract As mold material for glass lens with microstructures, it requires not only excellent mechanical properties, high thermal stability and oxidation resistance, but also satisfying machinability Using combinatorial arc plasma deposition, Ni-Nb-Ti thin film libraries were deposited for evaluations of some properties, such as, crystallization temperature, thermal stabilities, hardness, oxidation resistance and so on When Ni within 40-58 at %, Nb within 24-46 at %, Ti within 5-20 at %, the thin film exhibited excellent thermal stability However, for machinability, the conventional method can measure only one composition at each time which is both time-consuming and expensive Therefore, a novel combinatorial deposition and evaluation method for machinability are proposed In those methods, thin film samples with concentrically grading composition are sputter - deposited using combination targets The sample has grading compositions of which in the center Ti content is rich and becomes gradually decreasing from center to edge This means that each position on the surface of sample represents a particular composition Then this sample will be cut at different positions After that, cutting depth and the roughness of cutting surfaces will be measured It is clearly to see this new method is more efficient than conventional method, which is able to measure a lot of compositions' machinability at one time with one sample

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For prediction of surface roughening behavior, an inhomogeneous finite element (FE) simulation of micro deep drawing is conducted Grain shape is modeled by cubic and voronoi tessellationi in the FE model Materials used are pure copper foils with thickness of 0.05mm and 16.7μm The micro deep drawing apparatus with punch diameter of 0.85mm and die diameter of 0.95mm is used to verify the validity of the FE simulation As a result, the surface roughness during micro deep drawing obtained from the FE simulation is in good agreement with that of experiment The validity of proposed inhomogeneous FE model can be verified for the micro deep drawing process with contact situation between material and dies In addition, modeling of grain shapes between cubic and voronoi tessellationi has no effect on surface roughness during the micro deep drawing

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We fabricated thin-film thermoelectric generators and evaluated their generation properties using focused solar light Thin-film thermoelectric elements of Bi_<0.5>Sb_<1.5>Te_<0.3> (p-type) and Bi_2Te_<2.7>Se_<0.3> (n-type), were deposited on glass substrates by radiofrequency magnetron sputtering, and patterned using lift-off techniques After patterning the module, annealing treatment was carried out in a vacuum at 300℃ for 1 h Solar light was focused onto the hot side of the thin-film thermoelectric module with 10 pn junctions using convex lens The focal spot was approximately 2 mm with solar concentration of 156 suns The temperature difference between the hot and cold sides of pn junctions was approximately 90℃ Under this condition, the open circuit voltage and maximum generation power were 245 mV and 1.2 μW, respectively This value of the open circuit voltage of the module was consistent with the calculated value using Seebeck coefficient of thermoelectric thin films and the temperature difference of the module

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Porous aluminum is a lightweight material with high energy absorption properties In this study, porous aluminum was fabricated by friction stir processing (FSP) using ADC 12 aluminum alloy die-casting, which has high productivity and high recyclability The effect of amount of Al_20_3 addition on the pore structure was investigated It was considered that 2mass% addition of Al_20_3 was optimum for fabricating high quality porous aluminum

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Porous aluminum (Al) is a lightweight with high energy absorption properties and expected as structural materials In this study, porous Al core filled m Al pipe composite materials was fabricated by friction welding Precursor of porous Al was fabricated by mixing the Al plates and blowing agent powder by friction stir welding route Obtained precursor was put into the Al pipe, and rotating tool was pressed into the precursor Then, bonding Al precursor to Al pipe can be conducted by mean of plastic flow Porous Al core filled in Al pipe composite materials with metal bonding was successfully fabricated by heating the precursor By using X-ray CT, pore structure of inside porous Al was observed

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Open-cell porous aluminum (Al) was fabricated by friction powder compaction (FPC) process without using external heat sources In this process, powder mixture of Al powder and sodium chloride (NaCl) powder as spacer particle was used as starting material The compacting and sintering of the mixture were conducted only by rotating tool plunged into a die and mixture NaCl was removed by placing the sintered mixture m water In this study, pore structures of obtained porous Al were nondestructively observed by X-ray CT In addition, a relationship between porosity and compression properties of obtained porous Al were investigated

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Porous aluminum is a multifunctional material with lightweight and high energy absorption properties In this study, porous aluminum bending test specimen was fabricated by friction stir processing route Pore structure of fabricated porous aluminum specimen was observed nondestructively by X-ray computed tomography The bending property and deformation behavior of porous aluminum was obtained by conducting bending test It was shown that the fabricated porous aluminum bending specimen deformed from the position subjected to maximum bending stress

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After low carbon steel transforms austenite phase to martensite, that is martensitic transformation, one austenite crystal divides mto new and small several crystals called variants At this time the crystal orientation relationship between these crystals in both phases follows the Kurdjumov-Sacks (K-S) relationship and some researchers claimed that an austenite could nucleate the 24 variants according to the theory In this study we identified an austenite crystal from the variants pattern obtained by the electron back scatter diffraction (EBSD) and found the variant pairs in the patterns There were 22 variants in the pairs so that an austenite crystal could nucleate all of the variants during the martensitic transformation

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Intergranular stress corrosion cracking tests by using fretting contacts with high stress ratio were conducted All of the initiated cracks were intergranular manner due to crevice corrosion and removal of surface oxide layer by frictions The crack growth rate revealed higher value than that of large cracks, which demonstrated small crack effect on intergranular cracking

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Kyoto is a city with a long histoiy, which brings out a serious of traditional craft products, such as 'Kana-ami'---a kind of metal wire network 'Kana-ami' was all made by hand work And the product's quality was judged by the standard structure, which was established and developed in the long course of history and culture That aesthetical standard has already been consistently rooted into Japanese peoples" heart deeply However, the 'Kana-ami' shops in Kyoto have decreased dramatic Therefore, it is urgent time to try to do something to keep this traditional culture wealth In this research, cooperating with "Kanaami Tsuji" workshop, 38 metal wire net products made by 38 students were chosen as the non-expert subjects compared with the excellent products of Mr Tsuji and his son So, the average hexagon angles were treated as the standard in this study All hexagon angles of students' final product were investigated and measured, and averaged value of different oblique weaving line was calculated and compared with corresponding angle standard Based on this structure evaluation system, hexagon angles of Mr Tsuji product showed whole uniform and consistence, which reflected Mr Tsuji' motion stability during weaving process

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The Japanese tradition technique is supported by natural material, manual tools and the expert human skill The skill has been handed down between individuals as the personal tacit knowledge cultivated with response feeling of ancient people The long-term trial and error is necessary for learning this To analyze this tacit knowledge is expected to apply to another field and to shorten technique acquisition period by scientific elucidation In addition, there is tacit knowledge in the both sides of the response feeling of skilled users and the manufacturing feeling of the tool maker By solving this tacit knowledge in the traditional technique the advanced application will be expected to nano-technology in the modern manufacturing process

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In previous reports we have found the significant flow differences of kyo-wall compound according to trowel materials with high speed VTR image analysis and the f unction of the old Mizunaze trowel forged by Japanese sword technology inducing peculiar high flow of clay and water compound In this report we have investigated "Noro" water with minute clay exuding from the surface just after applying the earthen compound with the fluid mechanical measurement, kneading test with trowels of every forging stages, the dielectric constant measurement of the surface and bulk water molecules, the X-ray diffraction measurement and the scanning electron microscope. "Noro" exuding mechanism related to the interaction of clay and water molecule which leads to the aesthetic appearance of the Kyo-wall will be reported

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This study used the EMG (electromyography) machine telemeter System WEB- 1000 to record the muscle activity and the sampling rate 1,000 Hz was used as the record condition of the bamboo moisture by immersed bamboo in water on 4-hour and 3-day would affect the muscle activity during separated bamboo by bending process Thirteen muscles which bilateral side of Pectoralis major, Biceps brachii, Triceps brachii, Latissimus dorsi, Gluteus medius and only right side of Rectus abdominis, Extensor carpi radialis longus and Flexor carpi radialis were recorded As a result, the bilateral side of Biceps brachii, right side of Extensor carpi radialis longus and Flexor carpi radialis, left side of Triceps brachii showed the difference quite clearly When the craftsman was bending the bamboo he was necessary more effortful by these muscles activity on the 4-hour immersed bamboo in water than the 3-day

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The Maki-e is one of decoration techniques of Japanese traditional Urushi lacquer works which depends on the experience and intuition of experts who trained the techniques for a long time There is not so much scientific research about skill transfer in this field, because it is too difficult to inherit the technique from experts to inexperts However, the techniques of traditional crafts are important elements to support and develop national manufacturing The purpose of this research is to quantify Fun-maki, which is the technique of spreading Maki-e powder on the Urushi surface The result of this research is useful to the successor upbringing The pattern of muscle activity during Fun-maki motion of 4 subjects were compared with surface electromyogram As a result, muscle activity of the high career expert was quite different compared with other subjects High career experts' muscle activity was stable while the disorder of the muscle activity of the arm muscle was observed in the case of other subjects Therefore, it was found that the stability of the trunk of the body was indispensable to move the tip of a finger freely

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This paper describes about a turbidity measurement method for translucent objects In our method, we project a stripe pattern on to a translucent sample and evaluate the turbidity from its contrast Generally, a plastic is the translucent object which light is easy to penetrate Therefore, the plastic has a character of visual feel We made some plastic samples whose turbidity were different and applied our method to those samples Experimental results showed that we could measure turbidity without depending on the thickness of the sample Moreover, we applied our method to a clear black sample also Experimental result showed that projected stripe pattern was appeared not only on the surface of the sample but also inside of the sample We are going to try an evaluation of visual feel about plastic products and rhus lacquer products m future

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The purpose of this study was to study the heat treatment of forged trowel blade process and studied the affect of grain size whether altering the head of the hammer after forged Experiments were conducted the trowel blade which was made from SK5 steel Microstructure was accurately measured by using the optical microscope (OM) The resultant microstructures of hard ening are observed as martensite After the tempering process, the result of microstructure found the bainite structure In the hardening process was heated up 800-850℃ to austenite structure and quenched in cooling oil Moreover, in the annealing process was quenched into straw ashes for cooling after heat up until 750℃ This study found the size of hammer affect grain size structure therefore the grain size of forged hammer hand tool smaller than grain size of forged hammer machine

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浸炭熱処理の品質保証は鏡面仕上げされた金相試験片を使用する.この試験片の作成工程は規格で決められているが,出来栄えは検査員の経験や技に依存する 本研究では熟練者と非熟練者の試験片の研磨工程と試験結果の違いを比較した その結果,研磨後の観察時間,試験圧力の変化,試験結果の違いを明らかにした.

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The expert worker (85 years old) has worked for 70 years and the non expert (16 years old) has worked 1 year of experience for the lathe processing The subjects were compared the difference in the waist, the shoulder and the fore arm movement between the two worker while they were chucking on the lathe machine Determination used the same parts and the same type of lathe machine for investigated There were 4 main categories that related three standing position alignment and two hand positions on the key chuck Using the 6 infrared cameras and 2 video cameras captured the position of each marker All markers position data which synchronization was taken by a motion analysis system (sampling rate 100Hz) As a results show the balance movement both the waist and the shoulder during the chucking that had significantly greater in the expert worker than the non expert worker Only standing position of expert influenced on distance of movement

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