The purpose of this study is to clarify a possibility of the eco-cutting process for the super heat-resistant alloy Inconel 718. The experimental cutting by turning has been conducted for the improvement of the cutting efficiency of a difficult-to-machine material such as a super heat-resistant alloy Inconel 718 for the protection of the global environment. The cutting processes in the experiments are a dry cutting, a wet cutting with emulsion coolant and an oil-mist cutting. In the experiment, a HW-K10 cemented carbide insert, a Ti compound cermet insert, a TiCN-Al₂O₃-Ti compound CVD coated cemented carbide insert and a (Ti,Al)N PVD coated cemented carbide insert were used for the turning of the periphery of round bars. It was found that the Inconel 718 of extremely low machinability can be machined at a cutting speed of 100m/min using a combination of (Ti,Al)N PVD coated cemented carbide insert and vegetable oil mist 12ml/h with 0.5MPa air.

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Diamond-like carbon (DLC) is of great interest due to superior properties as a coating material, e.g., high hardness, high wear resistance and chemical stability. Recently, a focused ion-beam assisted chemical vapor deposition (FIB-CVD) method is proposed as a new technique for fabricating three dimensional micro- and/or nano- structures of DLC. Microstructures of this material are, however, not clear sufficiently so far. In this study, therefore, microstructures of DLC produced by the FIB-CVD method were examined. DLC films were prepared on three kinds of substrates by the FIB-CVD method. The microstructures of the films were characterized by high-resolution transmission electron microscopy (HRTEM) equipped with energy dispersive spectroscopy (EDS) and electron energy loss spectroscopy (EELS). For the films on all substrates, HRTEM images and diffraction images indicated that the DLC films had amorphous structures. EDS analysis also indicated that Ga was included 3∼5 at.% and distributed homogeneously in all over the DLC films. The sp³ fraction in the DLC was estimated at 31∼32 % from EELS spectra. It was found that the microstructures, the Ga content and sp³ fraction were independent on substrates.

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The study deals with the development of a new method to machine the curved holes with a constant curvature by means of the apparatus developed by the authors. It is strongly required to machine curved holes for the fabrication of water channels built in a mold. This is due to the achievement of their efficient arrangement, which can improve the productivity in molding by shortening the solidifying time in a molding cycle. However, the efficient arrangement cannot be realized since water channels are generally made by drilling, which causes their shape to be polygonal line. To meet the requirement, the authors developed the device which can fabricate curved holes by means of electrical discharge machining. Though the device is capable of machining various-shaped curved holes, the target shapes were not obtained since the control method and the utilized software were simple. In the study, therefore, a new method employing a vision sensor and its processing software are developed to control the device so skillfully that the curved holes with a constant curvature can be machined. From the experimental results, it is found that the developed control method has ability of accurately fabricating constant curvature curved holes.

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Polycrystalline silicon films were prepared by APPCVD (atmospheric pressure plasma CVD) with high deposition rate. The dependence of the Si film structures and deposition rate on silane concentration was investigated. The film growth has two stages depending on silane concentration. It was found that the silane concentration 0.02% was turning point of growth mode when plasma power was 2500W, hydrogen concentration was 10%. The achieved maximum deposition rate was 9nm/sec when silane concentration was 0.1%. The grain size was a few μm and the Si films were found to be composed wedge-shape grains perpendicular to substrate surface. Each crystallinity of the prepared Si films under all experimental conditions was above 80% from Raman scattering spectra. In region of low silane concentration, the crystallinity decreased with increase in silane concentration. The grain orientation of Si film was also strongly depended on silane concentration. The almost grains indicated ‹110› orientation under low silane concentration condition by XRD. But, higher silane concentration, the other crystal orientation, ‹111›, ‹311› became stronger. This orientation dependence on silane concentration was considered to be caused by the competition process between grain growth rate depending on crystal orientation and etching rate of films by atomic hydrogen generated by atmospheric plasma.

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A new finishing process for metal molds by large-area electron beam irradiation was proposed and the effects of EB irradiation conditions on surface finishing characteristics were clarified in the first report. As a result, the surface roughness could be reduced from 6μm to less than 1μm in just a few minutes under a proper condition, and so large-area electron beam irradiation method has a possibility of high efficient finishing process for metal molds. In this report, the surface smoothing of tilting surface is tried for actual use, since metal mold usually has many tilting surfaces. In addition, the surface characteristics of the EB irradiated surface are evaluated. The experimental results made it clear that the surface roughness can be improved, even if the surface tilting angle is close to 90 degrees, and that the corrosion resistance of metal mold surface could be improved by large-area EB irradiation. Moreover, the applicability of the large-area EB irradiation is shown for some practical metal molds.

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We propose a high-speed vertical scanning profilometry which has nanometric height precision. The proposed profilometry is equipped with two short-coherent-light sources, which are made of extremely-high-power light emitting diodes (LED). In 3-D profile measurements, the profilometry acquires many interferograms while vertically scanning a Mirau-type objective with 0.407-μm movement/interferogram and alternately-flashing LED. Odd-numbered interferograms are acquired with 503-nm LED and even-numbered interferograms are with 591-nm LED. Regarding the acquired interferograms, a computer calculates phase and modulation contrast using a phase-shifting technique. As two movements are repeated between acquirements of the same-color interferograms, phase step corresponds to approximately 6π + π/2 with 503 nm and approximately 6π - π/2 with 591 nm, respectively. After searching the interferogram having a contrast peak, the computer extracts optical path difference of the searched interferogram with nanometric resolution from the phase information. From the vertical movement length of 0.407 μm and a frame rate of 111 Hz, a vertical scanning speed is given as 45.2 μm/s. Nanometric height precision of the profilometry is checked using the measured data of a step height standard.

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In recent semiconductor lithography equipment, the error of distortion measurement is required to be at most 1 nm. With conventional methods of distortion measurement, however, the accuracy of measurement is insufficient, because it depends on the accuracy of XY-stage. This paper describes a new method for distortion measurement, which is an application of a least square serial two point method. The proposed method has an advantage over conventional methods for distortion measurement, because it is not affected by the accuracy of XY-stage. With the proposed method, the accuracy of distortion measurement is substantially improved and attains the required criterion.

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Ceramic nanoparticles reinforced photosensitive resins are developed by mixing ceramic nanoparticles (alumina-silica particles) with photosensitive resins uniformly to produce micro stereolithography parts with high mechanical properties. Micro Vickers hardness value is improved to 3.4 times higher than that of conventional photosensitive resins due to mixing the particles at the mixing rate of 50wt%. Also, the continuous laminating micro stereolithography method using grayscales as LCD mask images is proposed in order to reduce the surplus growth resulting from laminating with many layers and then enables to produce highly precise micro structures. Consequently, highly accurate micro bevel gears within maximum error rates of 3.6% are fabricated by using LCD mask with grayscales.

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This study analyzes the recognition process in the examination of the texture of fine particles through tactile sensing with human fingers, and aims at establishing the structure of texture recognition. Characteristic values of tactile sensing are looked for by the principal component analysis, and also by investigating a relationship between tactile sensing and its verbal response. In this study, it is understood that there are characteristic values of tactile sensing which is relative to the form of a fingerprint. These values are the threshold at which the tactile sensing switch. The correspondence between the diameters of the particles and the term expressed for the tactile sensing is also established.

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It is an extremely important matter to identify the noise sources and the noise emitted frequency, when abating the noise such as the engine noise, the machinery noise, etc. Moreover, the visualizing the noise sources is very useful for understanding the various noise problems intuitively. With these backgrounds, the previous study discussed the sound source identification methods and the visualization methods such as an acoustic holography (AH) method, a modified acoustic holography (MAH) method and a MUSIC method. However, there are few studies on the sound source identification method using a microphone directivity pattern. Nevertheless, we have to consider the directivity pattern of used microphones when we actually apply these identification methods. This paper discusses effect of the directivity pattern upon the identification error through the computation and the experimental examination when we used the AH, MAH and MUSIC methods. Furthermore, this paper proposes the identification methods which can consider the microphone directivity pattern for the AH, MAH and MUSIC methods.

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This paper reports on a study on the winding technology of continuous diamond coils for the stators of midsized rotating machinery. The winding support system has a 3-DOF nozzle drive unit, a winding form that can turn and roll, and a tensioner. It forms the rough shapes of the coils automatically on behalf of the worker. The worker finishes the coils according to the instructions on the display of this system. Moreover, the winding form has guides actuated both automatically and manually. They help the worker to put the wire in order and maintain the complicated shape of the coil. As a result, the rate of production has been tripled, and the workers don't need a lot of skill as they needed before this development.

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The temperature on the rake face of a binder-less cBN tool tip in end-milling was measured using a fiber-optic two-color pyrometer. The radiation of the interface between the tool tip and the chip is transmitted through the binder-less cBN and accepted by the optical fiber located behind the tool tip. The radiation accepted is transmitted to a two-color detector, which consists of a InAs and InSb detector, through a rotary fiber coupler. The coupler makes it possible to transmit the radiation outside the milling machine. The fundamental transmission characteristics of the coupler was investigated theoretically and experimentally. This method was found to be very practical to measure the tool tip temperature in end-milling. The results obtained are as follows. The rake face temperature in the up-milling of 0.55% carbon steel ranged from 480 degrees centigrade to 560 degrees centigrade for the cutting speeds of 2.2 m/s to 4.4 m/s. The cutting temperature increases with the increase of cutting speed. The temperature in down-milling is higher a little than that in the up-milling.

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In the paper, a two-dimensional (2-D) encoder using multi tunneling probe scanning tunneling microscope (STM) and a regular crystalline lattice is proposed. Two unit lattice vectors on a graphite crystalline surface, whose length and intersectional angle are 0.246 nm and 60°, respectively, are utilized as 2-D displacement references. 2-D displacement of a sample stage, on which graphite crystal is set, can be determined as a linear sum of the two unit lattice vectors which derived from multi current signals of the multiprobes of the STM. In the experiments, the proposed method is compared with a capacitance sensor. Dither modulations applied to STM probes are utilized to obtain multi current signals in a semi-realtime way. The results show the proposed method has a feasibility for measuring a 2-D displacement with resolution of less than 0.1 nm having a maximum measurement speed of 100 nm/s.

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This paper considers a simple fishing tackle consisting of a line segment and a submerged sinker at the bottom end. A preliminary experiment confirms that, for a inclined cylinder, the fluid drag acts along a direction normal to the cylinder axis. This property is used to derive a differential equation describing steady-state line shapes when the aerial top end is tagged in a stepwise way. A drag coefficient is then determined through a comparison of calculated and actual shapes at a steady state. A multi-link model using the drag coefficient can yield good predictions of unsteady-state line shapes observed during the tagging experiments. Another type of unsteady-state shape response is also calculated to illustrate a good performance of the proposed animation method.

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In coordinate metrology, it is the key technology to estimate the uncertainty of the measurement in a specific measuring strategy. In this paper, the influence of the systematic error in feature based metrology is theoretically analyzed to a line feature. When a line feature with a form deviation is measured with a coordinate measuring machine, the model which consists of a smooth curve of low frequency and a random error can describe the form deviation of the line feature. The technique of making the form deviation model of this line feature using a piecewise polynomial is proposed, and the method of calculating the parameters by least squares method is formulized. Furthermore, the evaluation indicator in the case of choosing a model and parameterization is shown. The reliability of the measured line feature is evaluated by applying error propagation to this method. Some simulations are statistically performed for this method and the concept of this paper and the usefulness of the fundamental data processing technique are confirmed.

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Application systems public on the Internet to support welding operations can be integrated to obtain extended functionality. In the paper, a method using WWW related technology is proposed, in which each application system being defined by input, output and function is connected in serial and/or parallel manner including branches by the interface defined in XML. The XML expressions are to be used not only to standardize the interface specifications but also to adjust terms used in each application into those suitable to be linked. For this purpose, an interpreter unit on the Internet is introduced. Three arc welding application system sites of welding process planning system, welding heat conduction simulator and welding CCT diagram database are connected based on the method as interactive system. The method is proved effective through case studies.

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This paper proposes an innovative two-step approach to the design of practical and sophisticated compliant mechanisms. The approach consists of two optimization methods : topology and shape optimizations, and a scheme to implement designer input of ideas. In the first step, a designer explores the most fruitful design concepts for mechanisms that achieve the design requirements by combining several compliant mechanisms generated by the topology optimization with additional mechanisms based on his or her ideas. This step integrates the topology optimization with a support method that assists the designer's exploration of new ideas and design concepts. In the second step, the shape optimization procedure yields a detailed optimal shape based on the design concept. The combination of initial compliant mechanisms and additional mechanisms based on a designer's ideas enables the creation of devices having higher performance or increased capability than would be possible using a single compliant mechanism alone. Executing the shape optimization at the second step facilitates the determination of a detailed optimal shape, and also makes it possible to consider stress concentration and make accurate quantitative performance evaluations, which neither topology optimization nor a designer's creative activity alone can provide.

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While a NURBS surface has restricted blending functions, a surface with scattered control points has independent blending functions. Because each control point has an independent sub-domain, the surface is more flexible with NURBS-compatibility. However, a previous rectangular sub-domain strongly affects the surface generation. For example, it is not easy even to add a circular dimple on a surface. To improve the expression of the surface, this paper tries to expand the surface definition with reference to sub-domain. A sub-domain is newly given as a triangle, a circle or a polygon with each blending function. This paper discusses how the blending function should be given in order to guarantee the continuity. The implementation method for each sub-domain is also discussed. Consequently, through some examples of surface generation, this paper shows that the expansion inherits the characteristics of a surface with scattered control points and enhances the ability of surface expression using some proposed sub-domains.

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